TBD Meeting (4663-21)

The antibody-drug conjugate enfortumab vedotin is superior to chemotherapy in patients with previously treated advanced urothelial carcinoma, primary results of the EV-301 trial show.

Findings were reported at the 2021 Genitourinary Cancers Symposium (Abstract 393).

“Treatment after platinum-based chemotherapy and immune checkpoint inhibitors is challenging. Overall survival is short, and therapeutic options are also limited,” noted first author Thomas Powles, MD, a professor of genitourinary oncology and director of the Barts Cancer Centre, Queen Mary University of London. “Chemotherapy is being used as the global standard of care, but randomized trials supporting these treatment choices are actually lacking. In this setting, new therapeutic agents supported by randomized trials are needed.”

Patients enrolled in EV-301 (NCT03474107), an international open-label, phase 3 trial, had locally advanced or metastatic urothelial carcinoma, had received platinum-based chemotherapy, and had experienced progression during or after immune checkpoint inhibitor therapy (anti–PD1/PD-L1 therapy).

The trial met its primary endpoint, showing that, relative to chemotherapy, enfortumab vedotin reduced the risk of death by 30%, giving patients nearly 4 additional months of life. The toxicity profile was similar to that seen in earlier trials and was manageable.

“Enfortumab vedotin is the first drug, beyond chemotherapy and immunotherapy, to show a significant survival advantage in previously treated urothelial cancer. This is a big step in the right direction for patients with advanced urothelial cancer, where treatment options remain quite limited,” Dr. Powles maintained.

The drug is also showing promising activity when used in the immunotherapy-treated but cisplatin-ineligible patients in the second cohort of the predecessor EV-201 trial, reported at the symposium as well (Abstract 394), he noted. “I hope that, as we move it earlier, we will show better efficacy.”

The Food and Drug Administration granted enfortumab vedotin accelerated approval as third-line therapy in 2019 on the basis of data from the EV-201 trial’s first cohort. With these new data from both trials, the manufacturers have submitted applications to convert the accelerated approval to regular approval, and to expand the current label to include cisplatin-ineligible patients.
 

Trial details

In EV-301, a total of 608 patients were randomized evenly to enfortumab vedotin (an antibody-drug conjugate that targets nectin-4, a cell-adhesion molecule highly expressed in urothelial carcinoma) or the physician’s choice among three standard chemotherapy options having similar efficacy (docetaxel, paclitaxel, or vinflunine).

“None of these chemotherapy drugs have spectacular response rates, and the overall survival is best described as modest,” Dr. Powles said.

He reported results of the trial’s planned interim analysis, which became the primary analysis because the primary endpoint was positive. Specifically, median overall survival was 12.9 months with enfortumab vedotin and 9.0 months with chemotherapy (hazard ratio, 0.70; P = .00142). Benefit was similar across most patient subgroups.

The enfortumab vedotin group also had a better median progression-free survival (5.6 vs. 3.7 months; HR, 0.62; P < .00001) and investigator-assessed overall response rate (40.6% vs. 17.9%; P < .001).

The rate of grade 3 or worse treatment-related adverse events was 51% with enfortumab vedotin and 50% with chemotherapy. The former was associated with a higher rate of grade 3 or worse maculopapular rash (7% vs. 0%), whereas the latter was associated with higher rates of grade 3 or worse decreased neutrophil count (13% vs. 6%), decreased white blood cell count (7% vs. 1%), and febrile neutropenia (6% vs. 1%).

Regarding events of special interest, enfortumab vedotin led to more grade 3 or worse skin reactions of any type (15% vs. 1%), peripheral neuropathy (5% vs. 2%), and hyperglycemia (4% vs. 0%). However, the majority of all treatment-related adverse events of special interest were mild to moderate in severity and consistent with those previously reported.

“There is a skill associated with the management of toxicity, and there is going to be a learning curve for people who haven’t used the drug before,” Dr. Powles acknowledged. “But my experience is, it’s a manageable drug, and delays and dose interruptions actually make it a relatively straightforward drug to give in the context of the profile that we’ve seen today.”
 

Level 1 evidence

“We now know that enfortumab vedotin is here to stay in the armamentarium for the treatment of urothelial cancer, adding its name to the ranks of others which have shown level 1 evidence, proof of a survival benefit in metastatic urothelial carcinoma,” commented invited discussant Arlene O. Siefker-Radtke, MD, a professor in the department of genitourinary medical oncology, University of Texas MD Anderson Cancer Center, Houston.

“I’ve been impressed not only by the activity of enfortumab vedotin in visceral and liver metastases, but also by the impact in patients with bone metastases as this appears very helpful in controlling bone pain in many patients,” she noted.

Preventing and managing toxicity requires appropriate patient selection, careful monitoring, and dose modifications, with knowledge of the agent’s adverse event profile and of factors conferring elevated risk for events, Dr. Siefker-Radtke said.

“The early evidence for enfortumab vedotin in the postimmunotherapy, platinum-ineligible group suggests that this can help treat patients with an unmet need due to their inability to receive platinum-based therapy,” she concluded. “And while it’s currently approved in the third-line setting, we are all eagerly awaiting the outcomes of the frontline studies of enfortumab vedotin combined with pembrolizumab, which showed such a promising objective response rate, as has been presented at earlier meetings.”

The trial was sponsored by Astellas Pharma and Seagen. Dr. Powles disclosed relationships with Astellas Pharma, AstraZeneca, Bristol-Myers Squibb, and numerous other pharmaceutical and biotechnology companies. Dr. Siefker-Radtke disclosed relationships with AstraZeneca, Bavarian Nordic, Bristol-Myers Squibb, and a variety of other pharmaceutical and biotechnology companies, as well as patents, royalties, and/or other intellectual property pertaining to methods of characterizing and treating molecular subsets of muscle-invasive bladder cancer.

The antibody-drug conjugate enfortumab vedotin is superior to chemotherapy in patients with previously treated advanced urothelial carcinoma, primary results of the EV-301 trial show.

Findings were reported at the 2021 Genitourinary Cancers Symposium (Abstract 393).

“Treatment after platinum-based chemotherapy and immune checkpoint inhibitors is challenging. Overall survival is short, and therapeutic options are also limited,” noted first author Thomas Powles, MD, a professor of genitourinary oncology and director of the Barts Cancer Centre, Queen Mary University of London. “Chemotherapy is being used as the global standard of care, but randomized trials supporting these treatment choices are actually lacking. In this setting, new therapeutic agents supported by randomized trials are needed.”

Patients enrolled in EV-301 (NCT03474107), an international open-label, phase 3 trial, had locally advanced or metastatic urothelial carcinoma, had received platinum-based chemotherapy, and had experienced progression during or after immune checkpoint inhibitor therapy (anti–PD1/PD-L1 therapy).

The trial met its primary endpoint, showing that, relative to chemotherapy, enfortumab vedotin reduced the risk of death by 30%, giving patients nearly 4 additional months of life. The toxicity profile was similar to that seen in earlier trials and was manageable.

“Enfortumab vedotin is the first drug, beyond chemotherapy and immunotherapy, to show a significant survival advantage in previously treated urothelial cancer. This is a big step in the right direction for patients with advanced urothelial cancer, where treatment options remain quite limited,” Dr. Powles maintained.

The drug is also showing promising activity when used in the immunotherapy-treated but cisplatin-ineligible patients in the second cohort of the predecessor EV-201 trial, reported at the symposium as well (Abstract 394), he noted. “I hope that, as we move it earlier, we will show better efficacy.”

The Food and Drug Administration granted enfortumab vedotin accelerated approval as third-line therapy in 2019 on the basis of data from the EV-201 trial’s first cohort. With these new data from both trials, the manufacturers have submitted applications to convert the accelerated approval to regular approval, and to expand the current label to include cisplatin-ineligible patients.
 

Trial details

In EV-301, a total of 608 patients were randomized evenly to enfortumab vedotin (an antibody-drug conjugate that targets nectin-4, a cell-adhesion molecule highly expressed in urothelial carcinoma) or the physician’s choice among three standard chemotherapy options having similar efficacy (docetaxel, paclitaxel, or vinflunine).

“None of these chemotherapy drugs have spectacular response rates, and the overall survival is best described as modest,” Dr. Powles said.

He reported results of the trial’s planned interim analysis, which became the primary analysis because the primary endpoint was positive. Specifically, median overall survival was 12.9 months with enfortumab vedotin and 9.0 months with chemotherapy (hazard ratio, 0.70; P = .00142). Benefit was similar across most patient subgroups.

The enfortumab vedotin group also had a better median progression-free survival (5.6 vs. 3.7 months; HR, 0.62; P < .00001) and investigator-assessed overall response rate (40.6% vs. 17.9%; P < .001).

The rate of grade 3 or worse treatment-related adverse events was 51% with enfortumab vedotin and 50% with chemotherapy. The former was associated with a higher rate of grade 3 or worse maculopapular rash (7% vs. 0%), whereas the latter was associated with higher rates of grade 3 or worse decreased neutrophil count (13% vs. 6%), decreased white blood cell count (7% vs. 1%), and febrile neutropenia (6% vs. 1%).

Regarding events of special interest, enfortumab vedotin led to more grade 3 or worse skin reactions of any type (15% vs. 1%), peripheral neuropathy (5% vs. 2%), and hyperglycemia (4% vs. 0%). However, the majority of all treatment-related adverse events of special interest were mild to moderate in severity and consistent with those previously reported.

“There is a skill associated with the management of toxicity, and there is going to be a learning curve for people who haven’t used the drug before,” Dr. Powles acknowledged. “But my experience is, it’s a manageable drug, and delays and dose interruptions actually make it a relatively straightforward drug to give in the context of the profile that we’ve seen today.”
 

Level 1 evidence

“We now know that enfortumab vedotin is here to stay in the armamentarium for the treatment of urothelial cancer, adding its name to the ranks of others which have shown level 1 evidence, proof of a survival benefit in metastatic urothelial carcinoma,” commented invited discussant Arlene O. Siefker-Radtke, MD, a professor in the department of genitourinary medical oncology, University of Texas MD Anderson Cancer Center, Houston.

“I’ve been impressed not only by the activity of enfortumab vedotin in visceral and liver metastases, but also by the impact in patients with bone metastases as this appears very helpful in controlling bone pain in many patients,” she noted.

Preventing and managing toxicity requires appropriate patient selection, careful monitoring, and dose modifications, with knowledge of the agent’s adverse event profile and of factors conferring elevated risk for events, Dr. Siefker-Radtke said.

“The early evidence for enfortumab vedotin in the postimmunotherapy, platinum-ineligible group suggests that this can help treat patients with an unmet need due to their inability to receive platinum-based therapy,” she concluded. “And while it’s currently approved in the third-line setting, we are all eagerly awaiting the outcomes of the frontline studies of enfortumab vedotin combined with pembrolizumab, which showed such a promising objective response rate, as has been presented at earlier meetings.”

The trial was sponsored by Astellas Pharma and Seagen. Dr. Powles disclosed relationships with Astellas Pharma, AstraZeneca, Bristol-Myers Squibb, and numerous other pharmaceutical and biotechnology companies. Dr. Siefker-Radtke disclosed relationships with AstraZeneca, Bavarian Nordic, Bristol-Myers Squibb, and a variety of other pharmaceutical and biotechnology companies, as well as patents, royalties, and/or other intellectual property pertaining to methods of characterizing and treating molecular subsets of muscle-invasive bladder cancer.

The antibody-drug conjugate enfortumab vedotin is superior to chemotherapy in patients with previously treated advanced urothelial carcinoma, primary results of the EV-301 trial show.

Findings were reported at the 2021 Genitourinary Cancers Symposium (Abstract 393).

“Treatment after platinum-based chemotherapy and immune checkpoint inhibitors is challenging. Overall survival is short, and therapeutic options are also limited,” noted first author Thomas Powles, MD, a professor of genitourinary oncology and director of the Barts Cancer Centre, Queen Mary University of London. “Chemotherapy is being used as the global standard of care, but randomized trials supporting these treatment choices are actually lacking. In this setting, new therapeutic agents supported by randomized trials are needed.”

Patients enrolled in EV-301 (NCT03474107), an international open-label, phase 3 trial, had locally advanced or metastatic urothelial carcinoma, had received platinum-based chemotherapy, and had experienced progression during or after immune checkpoint inhibitor therapy (anti–PD1/PD-L1 therapy).

The trial met its primary endpoint, showing that, relative to chemotherapy, enfortumab vedotin reduced the risk of death by 30%, giving patients nearly 4 additional months of life. The toxicity profile was similar to that seen in earlier trials and was manageable.

“Enfortumab vedotin is the first drug, beyond chemotherapy and immunotherapy, to show a significant survival advantage in previously treated urothelial cancer. This is a big step in the right direction for patients with advanced urothelial cancer, where treatment options remain quite limited,” Dr. Powles maintained.

The drug is also showing promising activity when used in the immunotherapy-treated but cisplatin-ineligible patients in the second cohort of the predecessor EV-201 trial, reported at the symposium as well (Abstract 394), he noted. “I hope that, as we move it earlier, we will show better efficacy.”

The Food and Drug Administration granted enfortumab vedotin accelerated approval as third-line therapy in 2019 on the basis of data from the EV-201 trial’s first cohort. With these new data from both trials, the manufacturers have submitted applications to convert the accelerated approval to regular approval, and to expand the current label to include cisplatin-ineligible patients.
 

Trial details

In EV-301, a total of 608 patients were randomized evenly to enfortumab vedotin (an antibody-drug conjugate that targets nectin-4, a cell-adhesion molecule highly expressed in urothelial carcinoma) or the physician’s choice among three standard chemotherapy options having similar efficacy (docetaxel, paclitaxel, or vinflunine).

“None of these chemotherapy drugs have spectacular response rates, and the overall survival is best described as modest,” Dr. Powles said.

He reported results of the trial’s planned interim analysis, which became the primary analysis because the primary endpoint was positive. Specifically, median overall survival was 12.9 months with enfortumab vedotin and 9.0 months with chemotherapy (hazard ratio, 0.70; P = .00142). Benefit was similar across most patient subgroups.

The enfortumab vedotin group also had a better median progression-free survival (5.6 vs. 3.7 months; HR, 0.62; P < .00001) and investigator-assessed overall response rate (40.6% vs. 17.9%; P < .001).

The rate of grade 3 or worse treatment-related adverse events was 51% with enfortumab vedotin and 50% with chemotherapy. The former was associated with a higher rate of grade 3 or worse maculopapular rash (7% vs. 0%), whereas the latter was associated with higher rates of grade 3 or worse decreased neutrophil count (13% vs. 6%), decreased white blood cell count (7% vs. 1%), and febrile neutropenia (6% vs. 1%).

Regarding events of special interest, enfortumab vedotin led to more grade 3 or worse skin reactions of any type (15% vs. 1%), peripheral neuropathy (5% vs. 2%), and hyperglycemia (4% vs. 0%). However, the majority of all treatment-related adverse events of special interest were mild to moderate in severity and consistent with those previously reported.

“There is a skill associated with the management of toxicity, and there is going to be a learning curve for people who haven’t used the drug before,” Dr. Powles acknowledged. “But my experience is, it’s a manageable drug, and delays and dose interruptions actually make it a relatively straightforward drug to give in the context of the profile that we’ve seen today.”
 

Level 1 evidence

“We now know that enfortumab vedotin is here to stay in the armamentarium for the treatment of urothelial cancer, adding its name to the ranks of others which have shown level 1 evidence, proof of a survival benefit in metastatic urothelial carcinoma,” commented invited discussant Arlene O. Siefker-Radtke, MD, a professor in the department of genitourinary medical oncology, University of Texas MD Anderson Cancer Center, Houston.

“I’ve been impressed not only by the activity of enfortumab vedotin in visceral and liver metastases, but also by the impact in patients with bone metastases as this appears very helpful in controlling bone pain in many patients,” she noted.

Preventing and managing toxicity requires appropriate patient selection, careful monitoring, and dose modifications, with knowledge of the agent’s adverse event profile and of factors conferring elevated risk for events, Dr. Siefker-Radtke said.

“The early evidence for enfortumab vedotin in the postimmunotherapy, platinum-ineligible group suggests that this can help treat patients with an unmet need due to their inability to receive platinum-based therapy,” she concluded. “And while it’s currently approved in the third-line setting, we are all eagerly awaiting the outcomes of the frontline studies of enfortumab vedotin combined with pembrolizumab, which showed such a promising objective response rate, as has been presented at earlier meetings.”

The trial was sponsored by Astellas Pharma and Seagen. Dr. Powles disclosed relationships with Astellas Pharma, AstraZeneca, Bristol-Myers Squibb, and numerous other pharmaceutical and biotechnology companies. Dr. Siefker-Radtke disclosed relationships with AstraZeneca, Bavarian Nordic, Bristol-Myers Squibb, and a variety of other pharmaceutical and biotechnology companies, as well as patents, royalties, and/or other intellectual property pertaining to methods of characterizing and treating molecular subsets of muscle-invasive bladder cancer.

Approximately half of all patients with locally advanced or metastatic urothelial cancer (la/mUC) are ineligible to receive cisplatin-based chemotherapy. They face poor outlooks and extremely limited treatment options.

A new study indicates that enfortumab vedotin (EV) can cause major, prolonged responses in most patients in that unfortunate setting.
 

EV is an antibody-drug conjugate directed against nectin-4, an immunoglobulin-like cell adhesion molecule that is highly expressed in UC, obviating the need for testing prior to treatment. It is internalized in malignant cells, with release of the active moiety (monomethyl auristatin E; MMAE). MMAE causes microtubule disruption, with resultant cell-cycle arrest and apoptosis.

EV received accelerated approval from the Food and Drug Administration in December 2019 after publication of the results from cohort 1 of the open-label, single-arm, phase 2 EV-201 study.

Arjun V. Balar, MD, of the Perlmutter Cancer Center at New York University Langone Health, presented results from cohort 2 of EV-201 – the cisplatin-ineligible cohort – at the 2021 Genitourinary Cancer Symposium (Abstract 394).
 

EV in patients ineligible for platinum-based therapy

Patients in cohort 2 of EV-201 had received immune checkpoint inhibitor therapy for la/mUC. They received EV in the FDA-approved dose for cohort 1: 1.25 mg/kg EV on days 1, 8, and 15 of a 28-day cycle.

Patients experienced disease progression during or following their most recent treatment. Patients with more than two neuropathies, active central nervous system metastases, and uncontrolled diabetes mellitus were excluded.

“Platinum ineligible” was defined as a creatinine clearance between 30-59 cm³/min, Eastern Cooperative Oncology Group performance status (ECOG PS) 2, or hearing loss of grade 2 or greater.

The primary endpoint for cohort 2 was confirmed overall response rate (ORR) per RECIST 1.1 by blinded independent central review. Secondary endpoints were duration of response, progression-free survival, overall survival, and safety.

There were 91 patients enrolled. Two patients never received EV treatment because of deterioration after registration. The median treatment duration among the remaining 89 patients was 6.0 months (range, 0.3-24.6).

Impressive results in poor-risk patients

The patients in EV-201 cohort 2 were elderly (median age, 75 years; range, 49-90) with comorbidities. The primary reasons for platinum-ineligibility were creatinine clearance less than 60 mL/min (66%), grade 2 or greater hearing loss (15%), and ECOG PS 2 (7%); 12% of patients met more than one criterion for platinum ineligibility.

The primary tumor site was in the upper urinary tract in 43% of patients, and 79% had visceral metastases, including 24% with liver involvement.

The confirmed ORR was 52% (95% confidence interval, 40.8-62.4), with 20% complete responses. There were responses in all subgroups, including patients with primary tumor sites in the upper tract (ORR, 61%), those with liver metastasis (ORR, 48%), and patients who had not responded to immune checkpoint inhibitors (ORR, 48%).

A total of 88% of patients had some decrease in measurable tumor diameters, generally within a few weeks of treatment initiation (median time to response, 1.8 months). The rapid response to treatment was especially important to patients having cancer-associated pain.

The median progression-free and overall survival durations were 5.8 months (95% CI, 5.0-8.3) and 14.7 months (95% CI, 10.5-18.2), respectively. The median response duration was 10.9 months (95% CI, 5.78-NR). More than 25% of responses extended beyond 12 months.

About 82% of patients in cohort 2 discontinued treatment, most commonly because of disease progression (51%). The second most common reason was the development of treatment-related adverse events (TRAE; 24%).
 

Drilling down on treatment-related adverse events

As might be expected for cisplatin-ineligible patients, adverse events were higher for patients in cohort 2 than for cohort 1 and led to treatment discontinuation in 16% of patients overall.

TRAEs over grade 3 occurred in 55% of patients. TRAEs of special interest included rash (61% overall; 17% ≥ grade 3), peripheral neuropathy (54% overall; 8% ≥ grade 3), and hyperglycemia (10% overall; 6% ≥ grade 3). Dose reductions, interruptions, and physical therapy were helpful.

Twenty percent of patients with TRAE hyperglycemia had hyperglycemia at baseline, and 30% of TRAEs were in patients with high body mass index (BMI).

There were four treatment-related deaths, all in patients 75 years or older with multiple comorbidities. Three of the four deaths occurred within 30 days of first EV dose in patients with BMI of 30 or greater (acute kidney injury, metabolic acidosis, and multiple organ dysfunction syndrome). The remaining death occurred more than 30 days after the last dose (pneumonitis).
 

Context and caution

The authors concluded that EV produced durable responses in platinum-ineligible patients with la/mUC, including 20% complete responses. Safety was felt to be as expected, given the known toxicities of the agent and the compromised medical condition of the patients studied.

The study discussant, Arlene O. Siefker-Radtke, MD, of the University of Texas MD Anderson Cancer Center, Houston, agreed that EV fills an unmet need, showing impressive responses in patients with visceral, liver, and bone metastases. She agreed that EV should be investigated across the spectrum of urothelial cancer.

Dr. Siefker-Radtke reminded attendees that the FDA package insert for EV described a 48% increase in the area under the concentration-time curve concentration of the MMAE active moiety in patients with mild hepatic impairment and that EV use should be avoided entirely in patients with moderate to severe liver disease.

She speculated whether augmented toxicity in patients with a high BMI could be attributable to clinically occult impaired hepatic function from fatty liver infiltration.

She indicated that clinicians should monitor closely patients with higher BMI and grade 3-4 hyperglycemia or elevated hemoglobin A1c levels and advised holding EV in patients who develop:

• Glucose levels above 250 mg/dL
• Peeling skin or bullous skin lesions. These lesions can be heralded by a diffuse erythematous or papillary rash in the preceding weeks.
• Grade 3 diarrhea or mucosal membrane toxicity of other types.

Notwithstanding concerns about toxicity and the need for monitoring, EV merits continued study in combination with other agents and in additional settings in the clinical spectrum of urothelial cancer. It is an important new option for oncologists caring for patients with urothelial cancer.

The EV-201 study was funded by Seagen. Dr. Balar and Dr. Siefker-Radtke disclosed relationships with Seagen and many other companies.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers, as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

Approximately half of all patients with locally advanced or metastatic urothelial cancer (la/mUC) are ineligible to receive cisplatin-based chemotherapy. They face poor outlooks and extremely limited treatment options.

A new study indicates that enfortumab vedotin (EV) can cause major, prolonged responses in most patients in that unfortunate setting.
 

EV is an antibody-drug conjugate directed against nectin-4, an immunoglobulin-like cell adhesion molecule that is highly expressed in UC, obviating the need for testing prior to treatment. It is internalized in malignant cells, with release of the active moiety (monomethyl auristatin E; MMAE). MMAE causes microtubule disruption, with resultant cell-cycle arrest and apoptosis.

EV received accelerated approval from the Food and Drug Administration in December 2019 after publication of the results from cohort 1 of the open-label, single-arm, phase 2 EV-201 study.

Arjun V. Balar, MD, of the Perlmutter Cancer Center at New York University Langone Health, presented results from cohort 2 of EV-201 – the cisplatin-ineligible cohort – at the 2021 Genitourinary Cancer Symposium (Abstract 394).
 

EV in patients ineligible for platinum-based therapy

Patients in cohort 2 of EV-201 had received immune checkpoint inhibitor therapy for la/mUC. They received EV in the FDA-approved dose for cohort 1: 1.25 mg/kg EV on days 1, 8, and 15 of a 28-day cycle.

Patients experienced disease progression during or following their most recent treatment. Patients with more than two neuropathies, active central nervous system metastases, and uncontrolled diabetes mellitus were excluded.

“Platinum ineligible” was defined as a creatinine clearance between 30-59 cm³/min, Eastern Cooperative Oncology Group performance status (ECOG PS) 2, or hearing loss of grade 2 or greater.

The primary endpoint for cohort 2 was confirmed overall response rate (ORR) per RECIST 1.1 by blinded independent central review. Secondary endpoints were duration of response, progression-free survival, overall survival, and safety.

There were 91 patients enrolled. Two patients never received EV treatment because of deterioration after registration. The median treatment duration among the remaining 89 patients was 6.0 months (range, 0.3-24.6).

Impressive results in poor-risk patients

The patients in EV-201 cohort 2 were elderly (median age, 75 years; range, 49-90) with comorbidities. The primary reasons for platinum-ineligibility were creatinine clearance less than 60 mL/min (66%), grade 2 or greater hearing loss (15%), and ECOG PS 2 (7%); 12% of patients met more than one criterion for platinum ineligibility.

The primary tumor site was in the upper urinary tract in 43% of patients, and 79% had visceral metastases, including 24% with liver involvement.

The confirmed ORR was 52% (95% confidence interval, 40.8-62.4), with 20% complete responses. There were responses in all subgroups, including patients with primary tumor sites in the upper tract (ORR, 61%), those with liver metastasis (ORR, 48%), and patients who had not responded to immune checkpoint inhibitors (ORR, 48%).

A total of 88% of patients had some decrease in measurable tumor diameters, generally within a few weeks of treatment initiation (median time to response, 1.8 months). The rapid response to treatment was especially important to patients having cancer-associated pain.

The median progression-free and overall survival durations were 5.8 months (95% CI, 5.0-8.3) and 14.7 months (95% CI, 10.5-18.2), respectively. The median response duration was 10.9 months (95% CI, 5.78-NR). More than 25% of responses extended beyond 12 months.

About 82% of patients in cohort 2 discontinued treatment, most commonly because of disease progression (51%). The second most common reason was the development of treatment-related adverse events (TRAE; 24%).
 

Drilling down on treatment-related adverse events

As might be expected for cisplatin-ineligible patients, adverse events were higher for patients in cohort 2 than for cohort 1 and led to treatment discontinuation in 16% of patients overall.

TRAEs over grade 3 occurred in 55% of patients. TRAEs of special interest included rash (61% overall; 17% ≥ grade 3), peripheral neuropathy (54% overall; 8% ≥ grade 3), and hyperglycemia (10% overall; 6% ≥ grade 3). Dose reductions, interruptions, and physical therapy were helpful.

Twenty percent of patients with TRAE hyperglycemia had hyperglycemia at baseline, and 30% of TRAEs were in patients with high body mass index (BMI).

There were four treatment-related deaths, all in patients 75 years or older with multiple comorbidities. Three of the four deaths occurred within 30 days of first EV dose in patients with BMI of 30 or greater (acute kidney injury, metabolic acidosis, and multiple organ dysfunction syndrome). The remaining death occurred more than 30 days after the last dose (pneumonitis).
 

Context and caution

The authors concluded that EV produced durable responses in platinum-ineligible patients with la/mUC, including 20% complete responses. Safety was felt to be as expected, given the known toxicities of the agent and the compromised medical condition of the patients studied.

The study discussant, Arlene O. Siefker-Radtke, MD, of the University of Texas MD Anderson Cancer Center, Houston, agreed that EV fills an unmet need, showing impressive responses in patients with visceral, liver, and bone metastases. She agreed that EV should be investigated across the spectrum of urothelial cancer.

Dr. Siefker-Radtke reminded attendees that the FDA package insert for EV described a 48% increase in the area under the concentration-time curve concentration of the MMAE active moiety in patients with mild hepatic impairment and that EV use should be avoided entirely in patients with moderate to severe liver disease.

She speculated whether augmented toxicity in patients with a high BMI could be attributable to clinically occult impaired hepatic function from fatty liver infiltration.

She indicated that clinicians should monitor closely patients with higher BMI and grade 3-4 hyperglycemia or elevated hemoglobin A1c levels and advised holding EV in patients who develop:

• Glucose levels above 250 mg/dL
• Peeling skin or bullous skin lesions. These lesions can be heralded by a diffuse erythematous or papillary rash in the preceding weeks.
• Grade 3 diarrhea or mucosal membrane toxicity of other types.

Notwithstanding concerns about toxicity and the need for monitoring, EV merits continued study in combination with other agents and in additional settings in the clinical spectrum of urothelial cancer. It is an important new option for oncologists caring for patients with urothelial cancer.

The EV-201 study was funded by Seagen. Dr. Balar and Dr. Siefker-Radtke disclosed relationships with Seagen and many other companies.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers, as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

Approximately half of all patients with locally advanced or metastatic urothelial cancer (la/mUC) are ineligible to receive cisplatin-based chemotherapy. They face poor outlooks and extremely limited treatment options.

A new study indicates that enfortumab vedotin (EV) can cause major, prolonged responses in most patients in that unfortunate setting.
 

EV is an antibody-drug conjugate directed against nectin-4, an immunoglobulin-like cell adhesion molecule that is highly expressed in UC, obviating the need for testing prior to treatment. It is internalized in malignant cells, with release of the active moiety (monomethyl auristatin E; MMAE). MMAE causes microtubule disruption, with resultant cell-cycle arrest and apoptosis.

EV received accelerated approval from the Food and Drug Administration in December 2019 after publication of the results from cohort 1 of the open-label, single-arm, phase 2 EV-201 study.

Arjun V. Balar, MD, of the Perlmutter Cancer Center at New York University Langone Health, presented results from cohort 2 of EV-201 – the cisplatin-ineligible cohort – at the 2021 Genitourinary Cancer Symposium (Abstract 394).
 

EV in patients ineligible for platinum-based therapy

Patients in cohort 2 of EV-201 had received immune checkpoint inhibitor therapy for la/mUC. They received EV in the FDA-approved dose for cohort 1: 1.25 mg/kg EV on days 1, 8, and 15 of a 28-day cycle.

Patients experienced disease progression during or following their most recent treatment. Patients with more than two neuropathies, active central nervous system metastases, and uncontrolled diabetes mellitus were excluded.

“Platinum ineligible” was defined as a creatinine clearance between 30-59 cm³/min, Eastern Cooperative Oncology Group performance status (ECOG PS) 2, or hearing loss of grade 2 or greater.

The primary endpoint for cohort 2 was confirmed overall response rate (ORR) per RECIST 1.1 by blinded independent central review. Secondary endpoints were duration of response, progression-free survival, overall survival, and safety.

There were 91 patients enrolled. Two patients never received EV treatment because of deterioration after registration. The median treatment duration among the remaining 89 patients was 6.0 months (range, 0.3-24.6).

Impressive results in poor-risk patients

The patients in EV-201 cohort 2 were elderly (median age, 75 years; range, 49-90) with comorbidities. The primary reasons for platinum-ineligibility were creatinine clearance less than 60 mL/min (66%), grade 2 or greater hearing loss (15%), and ECOG PS 2 (7%); 12% of patients met more than one criterion for platinum ineligibility.

The primary tumor site was in the upper urinary tract in 43% of patients, and 79% had visceral metastases, including 24% with liver involvement.

The confirmed ORR was 52% (95% confidence interval, 40.8-62.4), with 20% complete responses. There were responses in all subgroups, including patients with primary tumor sites in the upper tract (ORR, 61%), those with liver metastasis (ORR, 48%), and patients who had not responded to immune checkpoint inhibitors (ORR, 48%).

A total of 88% of patients had some decrease in measurable tumor diameters, generally within a few weeks of treatment initiation (median time to response, 1.8 months). The rapid response to treatment was especially important to patients having cancer-associated pain.

The median progression-free and overall survival durations were 5.8 months (95% CI, 5.0-8.3) and 14.7 months (95% CI, 10.5-18.2), respectively. The median response duration was 10.9 months (95% CI, 5.78-NR). More than 25% of responses extended beyond 12 months.

About 82% of patients in cohort 2 discontinued treatment, most commonly because of disease progression (51%). The second most common reason was the development of treatment-related adverse events (TRAE; 24%).
 

Drilling down on treatment-related adverse events

As might be expected for cisplatin-ineligible patients, adverse events were higher for patients in cohort 2 than for cohort 1 and led to treatment discontinuation in 16% of patients overall.

TRAEs over grade 3 occurred in 55% of patients. TRAEs of special interest included rash (61% overall; 17% ≥ grade 3), peripheral neuropathy (54% overall; 8% ≥ grade 3), and hyperglycemia (10% overall; 6% ≥ grade 3). Dose reductions, interruptions, and physical therapy were helpful.

Twenty percent of patients with TRAE hyperglycemia had hyperglycemia at baseline, and 30% of TRAEs were in patients with high body mass index (BMI).

There were four treatment-related deaths, all in patients 75 years or older with multiple comorbidities. Three of the four deaths occurred within 30 days of first EV dose in patients with BMI of 30 or greater (acute kidney injury, metabolic acidosis, and multiple organ dysfunction syndrome). The remaining death occurred more than 30 days after the last dose (pneumonitis).
 

Context and caution

The authors concluded that EV produced durable responses in platinum-ineligible patients with la/mUC, including 20% complete responses. Safety was felt to be as expected, given the known toxicities of the agent and the compromised medical condition of the patients studied.

The study discussant, Arlene O. Siefker-Radtke, MD, of the University of Texas MD Anderson Cancer Center, Houston, agreed that EV fills an unmet need, showing impressive responses in patients with visceral, liver, and bone metastases. She agreed that EV should be investigated across the spectrum of urothelial cancer.

Dr. Siefker-Radtke reminded attendees that the FDA package insert for EV described a 48% increase in the area under the concentration-time curve concentration of the MMAE active moiety in patients with mild hepatic impairment and that EV use should be avoided entirely in patients with moderate to severe liver disease.

She speculated whether augmented toxicity in patients with a high BMI could be attributable to clinically occult impaired hepatic function from fatty liver infiltration.

She indicated that clinicians should monitor closely patients with higher BMI and grade 3-4 hyperglycemia or elevated hemoglobin A1c levels and advised holding EV in patients who develop:

• Glucose levels above 250 mg/dL
• Peeling skin or bullous skin lesions. These lesions can be heralded by a diffuse erythematous or papillary rash in the preceding weeks.
• Grade 3 diarrhea or mucosal membrane toxicity of other types.

Notwithstanding concerns about toxicity and the need for monitoring, EV merits continued study in combination with other agents and in additional settings in the clinical spectrum of urothelial cancer. It is an important new option for oncologists caring for patients with urothelial cancer.

The EV-201 study was funded by Seagen. Dr. Balar and Dr. Siefker-Radtke disclosed relationships with Seagen and many other companies.

Dr. Lyss was a community-based medical oncologist and clinical researcher for more than 35 years before his recent retirement. His clinical and research interests were focused on breast and lung cancers, as well as expanding clinical trial access to medically underserved populations. He is based in St. Louis. He has no conflicts of interest.

Two new approaches to surveillance imaging after treatment of stage I testicular seminoma sharply reduce or eliminate radiation exposure relative to the standard approach, without substantially compromising relapse detection, the phase 3 TRISST study suggests.

Results were reported at the 2021 Genitourinary Cancers Symposium (Abstract 374).

“Stage I seminoma has a survival that approaches 100%. Over recent years, CT surveillance has become an international standard of care and has largely replaced the use of adjuvant treatment,” said investigator Robert A. Huddart, MRCP, FRCR, PhD, of The Royal Marsden NHS Foundation Trust, London.

“A typical surveillance protocol, however, consists of multiple CT scans taken over a period of a few years and results in quite a high diagnostic radiation dose, which has raised questions about the long-term risk of second malignancies related to this program,” he noted. “At the moment, there is no evidence base to inform how frequently imaging should be undertaken and the type of imaging that should be used.”

Results of TRISST showed that, with a median 6-year follow-up during which men were monitored with various surveillance protocols, 1.5% experienced a relapse that was advanced (stage IIC or higher) at detection.

The incidence of relapse was 0.3% with the standard schedule of seven abdominal surveillance scans and a statistically noninferior 2.8% with three more widely spaced scans. Also, compared with the standard CT scans, which yielded an incidence of 2.6%, MRI scans were noninferior, yielding an incidence of 0.6%.

“The three-scan schedule was noninferior to seven scans in our protocol, and in fact, with the three-scan schedule, we would use over 1,000 fewer scans at a cost of perhaps having four relapses that could have been avoided,” Dr. Huddart pointed out. “We can conclude that MRI is noninferior to CT and should be recommended to avoid irradiation. This study will provide an evidence base for making the transition to MRI, which is important. The MRI scan is more complex – it takes longer and is more resource heavy. So we do need to supply the evidence that it is the right thing to do for patients.”

Need for expertise in interpreting MRI scans is a valid concern, he acknowledged. “There is a degree of specialization in the UK for testis cancer management, and clearly, you had to be specialist to take part in the study. So I can’t say it is your everyday radiologist, but the data would suggest we actually saw less errors in terms of pickup with the MRI scan than with the CT scan,” he said. “You do need to have a level of expertise, but it doesn’t require super-specialist expertise. I suppose that will be a learning lesson for all of us, to learn better MRI interpretation if we are using MRI.”
 

Trial details

The 669 men randomized in TRISST (NCT00589537), a multicenter trial with a factorial and noninferiority design, had undergone orchiectomy for stage I seminoma and did not have any adjuvant therapy planned.

They were randomized once on number of surveillance scans: seven scans (at 6, 12, 18, 24, 36, 48, and 60 months) vs. three scans (at 6, 18, and 36 months). And they were randomized again on scan modality: CT versus MRI. All groups had similar follow-up otherwise, consisting of periodic chest radiographs, tumor marker tests, and clinical assessments.

The primary outcome, 6-year incidence of advanced relapse defined as stage IIC or higher (i.e., measuring 5 cm or greater) by Royal Marsden Hospital criteria, was chosen because, when the study began, this was the dividing point between using local therapy and using systemic multiagent chemotherapy to treat a relapse, Dr. Huddart explained.

Among men remaining on surveillance, compliance was good, with 94% of all scans attended and 79% performed on time, he reported.

Overall, 12% of the randomized population experienced a relapse of any stage during follow-up, with nearly all relapses occurring within the first 3 years.

The 6-year incidence of advanced relapse was just 1.5% in the entire trial population, lower than the 5.7% expected in trial planning, according to Dr. Huddart.

In intention-to-treat analyses, the incidence was 2.8% with the three-scan schedule and 0.3% with the seven-scan schedule, with the difference of 2.6% and the bounds of the 90% confidence interval falling within the predefined noninferiority margin of 5.7%.

Using three scans instead of seven scans increased the proportion of patients with relapse who had advanced stage from 3% to 20%. Four of the nine advanced relapses occurring with the three-scan schedule could possibly have been detected earlier with the seven-scan schedule.

The 6-year incidence of advanced relapse was 0.6% with MRI scans and 2.6% with CT scans. The difference of –1.9% and the bounds of the 90% confidence interval fell within the noninferiority margin. Use of MRI instead of CT reduced the proportion of patients with relapse who had advanced stage from 20% to 5%.

For both the scan frequency comparison and the scan modality comparison, findings were essentially the same in per protocol analyses and in analyses that instead looked at relapses measuring 3 cm or greater, according to Dr. Huddart.

Fully 89% of patients with advanced relapses were treated with chemotherapy only, and 56% of all patients with advanced relapse had a response to their treatment.

Most patients experiencing a relapse of any stage, 93%, were alive and free of disease at their most recent follow-up, Dr. Huddart reported. Overall survival for the trial population was 99% and similar across surveillance groups, with no deaths due to testicular cancer.
 

Risk-tailored surveillance

“Noninferiority trials are much more challenging than equivalence or superiority trials,” observed invited discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University, Turkey.

She expressed some reservations about TRISST results, including the much lower than expected incidence of advanced relapse, which may have affected comparisons, and problematic compliance, as about one-quarter of patients stopped surveillance before relapse or withdrew from the trial before 6 years of follow-up.

Recurrence after treatment of stage I seminoma is largely driven by the risk factors of tumor size exceeding 4 cm and presence of rete testis invasion, and 54% of TRISST patients did not have either of these factors, Dr. Laguna noted.

“While a more relaxed schedule may well suit those patients at low risk, more intense schedules will be appropriate for patients with risk factors,” she maintained. “I am pretty sure that the TRISST trial will impact future guideline recommendations, although still I think that one approach may not fit all.”

TRISST was funded by Cancer Research UK and the MRC Clinical Trials Unit. Dr. Huddart disclosed relationships with Janssen Oncology, Bayer, Bristol-Myers Squibb, Merck Sharp & Dohme, Nektar, and Roche. Dr. Laguna disclosed that she is chair of the EAU Testicular Cancer Guidelines Panel.

Two new approaches to surveillance imaging after treatment of stage I testicular seminoma sharply reduce or eliminate radiation exposure relative to the standard approach, without substantially compromising relapse detection, the phase 3 TRISST study suggests.

Results were reported at the 2021 Genitourinary Cancers Symposium (Abstract 374).

“Stage I seminoma has a survival that approaches 100%. Over recent years, CT surveillance has become an international standard of care and has largely replaced the use of adjuvant treatment,” said investigator Robert A. Huddart, MRCP, FRCR, PhD, of The Royal Marsden NHS Foundation Trust, London.

“A typical surveillance protocol, however, consists of multiple CT scans taken over a period of a few years and results in quite a high diagnostic radiation dose, which has raised questions about the long-term risk of second malignancies related to this program,” he noted. “At the moment, there is no evidence base to inform how frequently imaging should be undertaken and the type of imaging that should be used.”

Results of TRISST showed that, with a median 6-year follow-up during which men were monitored with various surveillance protocols, 1.5% experienced a relapse that was advanced (stage IIC or higher) at detection.

The incidence of relapse was 0.3% with the standard schedule of seven abdominal surveillance scans and a statistically noninferior 2.8% with three more widely spaced scans. Also, compared with the standard CT scans, which yielded an incidence of 2.6%, MRI scans were noninferior, yielding an incidence of 0.6%.

“The three-scan schedule was noninferior to seven scans in our protocol, and in fact, with the three-scan schedule, we would use over 1,000 fewer scans at a cost of perhaps having four relapses that could have been avoided,” Dr. Huddart pointed out. “We can conclude that MRI is noninferior to CT and should be recommended to avoid irradiation. This study will provide an evidence base for making the transition to MRI, which is important. The MRI scan is more complex – it takes longer and is more resource heavy. So we do need to supply the evidence that it is the right thing to do for patients.”

Need for expertise in interpreting MRI scans is a valid concern, he acknowledged. “There is a degree of specialization in the UK for testis cancer management, and clearly, you had to be specialist to take part in the study. So I can’t say it is your everyday radiologist, but the data would suggest we actually saw less errors in terms of pickup with the MRI scan than with the CT scan,” he said. “You do need to have a level of expertise, but it doesn’t require super-specialist expertise. I suppose that will be a learning lesson for all of us, to learn better MRI interpretation if we are using MRI.”
 

Trial details

The 669 men randomized in TRISST (NCT00589537), a multicenter trial with a factorial and noninferiority design, had undergone orchiectomy for stage I seminoma and did not have any adjuvant therapy planned.

They were randomized once on number of surveillance scans: seven scans (at 6, 12, 18, 24, 36, 48, and 60 months) vs. three scans (at 6, 18, and 36 months). And they were randomized again on scan modality: CT versus MRI. All groups had similar follow-up otherwise, consisting of periodic chest radiographs, tumor marker tests, and clinical assessments.

The primary outcome, 6-year incidence of advanced relapse defined as stage IIC or higher (i.e., measuring 5 cm or greater) by Royal Marsden Hospital criteria, was chosen because, when the study began, this was the dividing point between using local therapy and using systemic multiagent chemotherapy to treat a relapse, Dr. Huddart explained.

Among men remaining on surveillance, compliance was good, with 94% of all scans attended and 79% performed on time, he reported.

Overall, 12% of the randomized population experienced a relapse of any stage during follow-up, with nearly all relapses occurring within the first 3 years.

The 6-year incidence of advanced relapse was just 1.5% in the entire trial population, lower than the 5.7% expected in trial planning, according to Dr. Huddart.

In intention-to-treat analyses, the incidence was 2.8% with the three-scan schedule and 0.3% with the seven-scan schedule, with the difference of 2.6% and the bounds of the 90% confidence interval falling within the predefined noninferiority margin of 5.7%.

Using three scans instead of seven scans increased the proportion of patients with relapse who had advanced stage from 3% to 20%. Four of the nine advanced relapses occurring with the three-scan schedule could possibly have been detected earlier with the seven-scan schedule.

The 6-year incidence of advanced relapse was 0.6% with MRI scans and 2.6% with CT scans. The difference of –1.9% and the bounds of the 90% confidence interval fell within the noninferiority margin. Use of MRI instead of CT reduced the proportion of patients with relapse who had advanced stage from 20% to 5%.

For both the scan frequency comparison and the scan modality comparison, findings were essentially the same in per protocol analyses and in analyses that instead looked at relapses measuring 3 cm or greater, according to Dr. Huddart.

Fully 89% of patients with advanced relapses were treated with chemotherapy only, and 56% of all patients with advanced relapse had a response to their treatment.

Most patients experiencing a relapse of any stage, 93%, were alive and free of disease at their most recent follow-up, Dr. Huddart reported. Overall survival for the trial population was 99% and similar across surveillance groups, with no deaths due to testicular cancer.
 

Risk-tailored surveillance

“Noninferiority trials are much more challenging than equivalence or superiority trials,” observed invited discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University, Turkey.

She expressed some reservations about TRISST results, including the much lower than expected incidence of advanced relapse, which may have affected comparisons, and problematic compliance, as about one-quarter of patients stopped surveillance before relapse or withdrew from the trial before 6 years of follow-up.

Recurrence after treatment of stage I seminoma is largely driven by the risk factors of tumor size exceeding 4 cm and presence of rete testis invasion, and 54% of TRISST patients did not have either of these factors, Dr. Laguna noted.

“While a more relaxed schedule may well suit those patients at low risk, more intense schedules will be appropriate for patients with risk factors,” she maintained. “I am pretty sure that the TRISST trial will impact future guideline recommendations, although still I think that one approach may not fit all.”

TRISST was funded by Cancer Research UK and the MRC Clinical Trials Unit. Dr. Huddart disclosed relationships with Janssen Oncology, Bayer, Bristol-Myers Squibb, Merck Sharp & Dohme, Nektar, and Roche. Dr. Laguna disclosed that she is chair of the EAU Testicular Cancer Guidelines Panel.

Two new approaches to surveillance imaging after treatment of stage I testicular seminoma sharply reduce or eliminate radiation exposure relative to the standard approach, without substantially compromising relapse detection, the phase 3 TRISST study suggests.

Results were reported at the 2021 Genitourinary Cancers Symposium (Abstract 374).

“Stage I seminoma has a survival that approaches 100%. Over recent years, CT surveillance has become an international standard of care and has largely replaced the use of adjuvant treatment,” said investigator Robert A. Huddart, MRCP, FRCR, PhD, of The Royal Marsden NHS Foundation Trust, London.

“A typical surveillance protocol, however, consists of multiple CT scans taken over a period of a few years and results in quite a high diagnostic radiation dose, which has raised questions about the long-term risk of second malignancies related to this program,” he noted. “At the moment, there is no evidence base to inform how frequently imaging should be undertaken and the type of imaging that should be used.”

Results of TRISST showed that, with a median 6-year follow-up during which men were monitored with various surveillance protocols, 1.5% experienced a relapse that was advanced (stage IIC or higher) at detection.

The incidence of relapse was 0.3% with the standard schedule of seven abdominal surveillance scans and a statistically noninferior 2.8% with three more widely spaced scans. Also, compared with the standard CT scans, which yielded an incidence of 2.6%, MRI scans were noninferior, yielding an incidence of 0.6%.

“The three-scan schedule was noninferior to seven scans in our protocol, and in fact, with the three-scan schedule, we would use over 1,000 fewer scans at a cost of perhaps having four relapses that could have been avoided,” Dr. Huddart pointed out. “We can conclude that MRI is noninferior to CT and should be recommended to avoid irradiation. This study will provide an evidence base for making the transition to MRI, which is important. The MRI scan is more complex – it takes longer and is more resource heavy. So we do need to supply the evidence that it is the right thing to do for patients.”

Need for expertise in interpreting MRI scans is a valid concern, he acknowledged. “There is a degree of specialization in the UK for testis cancer management, and clearly, you had to be specialist to take part in the study. So I can’t say it is your everyday radiologist, but the data would suggest we actually saw less errors in terms of pickup with the MRI scan than with the CT scan,” he said. “You do need to have a level of expertise, but it doesn’t require super-specialist expertise. I suppose that will be a learning lesson for all of us, to learn better MRI interpretation if we are using MRI.”
 

Trial details

The 669 men randomized in TRISST (NCT00589537), a multicenter trial with a factorial and noninferiority design, had undergone orchiectomy for stage I seminoma and did not have any adjuvant therapy planned.

They were randomized once on number of surveillance scans: seven scans (at 6, 12, 18, 24, 36, 48, and 60 months) vs. three scans (at 6, 18, and 36 months). And they were randomized again on scan modality: CT versus MRI. All groups had similar follow-up otherwise, consisting of periodic chest radiographs, tumor marker tests, and clinical assessments.

The primary outcome, 6-year incidence of advanced relapse defined as stage IIC or higher (i.e., measuring 5 cm or greater) by Royal Marsden Hospital criteria, was chosen because, when the study began, this was the dividing point between using local therapy and using systemic multiagent chemotherapy to treat a relapse, Dr. Huddart explained.

Among men remaining on surveillance, compliance was good, with 94% of all scans attended and 79% performed on time, he reported.

Overall, 12% of the randomized population experienced a relapse of any stage during follow-up, with nearly all relapses occurring within the first 3 years.

The 6-year incidence of advanced relapse was just 1.5% in the entire trial population, lower than the 5.7% expected in trial planning, according to Dr. Huddart.

In intention-to-treat analyses, the incidence was 2.8% with the three-scan schedule and 0.3% with the seven-scan schedule, with the difference of 2.6% and the bounds of the 90% confidence interval falling within the predefined noninferiority margin of 5.7%.

Using three scans instead of seven scans increased the proportion of patients with relapse who had advanced stage from 3% to 20%. Four of the nine advanced relapses occurring with the three-scan schedule could possibly have been detected earlier with the seven-scan schedule.

The 6-year incidence of advanced relapse was 0.6% with MRI scans and 2.6% with CT scans. The difference of –1.9% and the bounds of the 90% confidence interval fell within the noninferiority margin. Use of MRI instead of CT reduced the proportion of patients with relapse who had advanced stage from 20% to 5%.

For both the scan frequency comparison and the scan modality comparison, findings were essentially the same in per protocol analyses and in analyses that instead looked at relapses measuring 3 cm or greater, according to Dr. Huddart.

Fully 89% of patients with advanced relapses were treated with chemotherapy only, and 56% of all patients with advanced relapse had a response to their treatment.

Most patients experiencing a relapse of any stage, 93%, were alive and free of disease at their most recent follow-up, Dr. Huddart reported. Overall survival for the trial population was 99% and similar across surveillance groups, with no deaths due to testicular cancer.
 

Risk-tailored surveillance

“Noninferiority trials are much more challenging than equivalence or superiority trials,” observed invited discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University, Turkey.

She expressed some reservations about TRISST results, including the much lower than expected incidence of advanced relapse, which may have affected comparisons, and problematic compliance, as about one-quarter of patients stopped surveillance before relapse or withdrew from the trial before 6 years of follow-up.

Recurrence after treatment of stage I seminoma is largely driven by the risk factors of tumor size exceeding 4 cm and presence of rete testis invasion, and 54% of TRISST patients did not have either of these factors, Dr. Laguna noted.

“While a more relaxed schedule may well suit those patients at low risk, more intense schedules will be appropriate for patients with risk factors,” she maintained. “I am pretty sure that the TRISST trial will impact future guideline recommendations, although still I think that one approach may not fit all.”

TRISST was funded by Cancer Research UK and the MRC Clinical Trials Unit. Dr. Huddart disclosed relationships with Janssen Oncology, Bayer, Bristol-Myers Squibb, Merck Sharp & Dohme, Nektar, and Roche. Dr. Laguna disclosed that she is chair of the EAU Testicular Cancer Guidelines Panel.

The combination of lenvatinib and pembrolizumab outperforms sunitinib as first-line therapy for advanced clear-cell renal cell carcinoma (RCC), based on findings of the CLEAR trial.

Courtesy of Memorial Sloan Kettering Cancer Center

Results from the phase 3 trial were reported at the 2021 Genitourinary Cancers Symposium (Abstract 269) and simultaneously published in the New England Journal of Medicine.

Early-phase trials have shown the promise of targeting RCC from two angles, with both antiangiogenic therapy and immunotherapy, said presenter Robert J. Motzer, MD, of Memorial Sloan Kettering Cancer Center, New York.

The CLEAR trial was designed to compare monotherapy with sunitinib to treatment with lenvatinib plus either pembrolizumab or everolimus.

The risk of progression-free survival events was 61% lower with lenvatinib-pembrolizumab and 35% lower with lenvatinib-everolimus, compared with sunitinib. However, only the first combination significantly reduced the risk of death.

Treatment-related adverse events were more common with both combinations but manageable with dose modifications.

“These results support lenvatinib plus pembrolizumab as a potential first-line treatment for patients with advanced RCC,” Dr. Motzer said.

Oncologists will likely soon have a handful of first-line options from which to choose, he acknowledged.

“It is a great situation, that we have made such progress in RCC with IO [immuno-oncology] therapy in the first line with ipilimumab-nivolumab, and now with the IO-TKI [tyrosine kinase inhibitor] combinations,” Dr. Motzer said.

The choice will probably come down to personal preference, experience with the various combinations, and side effect profiles, he speculated.

“I will say, however, that the data with lenvatinib-pembrolizumab is very impressive in terms of the long progression-free survival, in terms of the doubling of response rate to over 70%, in terms of the 16% complete response rate,” he said.
 

Trial details

The CLEAR investigators evenly randomized 1,069 patients with advanced clear-cell RCC who had not received prior systemic therapy to treatment with lenvatinib-pembrolizumab, lenvatinib-everolimus, or sunitinib.

The primary analysis was conducted at a median follow-up of 27 months.

The median progression-free survival was 9.2 months with sunitinib, 23.9 months with lenvatinib-pembrolizumab (hazard ratio, 0.39; P < .001), and 14.7 months with lenvatinib-everolimus (HR for events, 0.65; P < .001).

Findings were similar across key subgroups, including International Metastatic RCC Database Consortium risk groups.

An interim analysis of overall survival showed that patients lived significantly longer with lenvatinib-pembrolizumab versus sunitinib (HR, 0.66; P = .005), with similar benefit across subgroups, except for the favorable risk group.

In contrast, lenvatinib-everolimus did not significantly improve overall survival (HR, 1.15; P = .3). The median overall survival was not reached in any treatment arm.

“To me, this emphasizes the role of IO therapy combinations in the first line. I think you need the IO in the first line to get the dramatic efficacy results that we saw in the CLEAR study,” Dr. Motzer said.

The confirmed objective response rate was 36.1% with sunitinib, 71.0% with lenvatinib-pembrolizumab (relative risk, 1.97; P < .001), and 53.5% with lenvatinib-everolimus (RR, 1.48; P <.001). The median duration of response was 14.6 months, 25.8 months, and 16.6 months, respectively.

Grade 3 or higher treatment-related adverse events occurred in 58.8% of patients in the sunitinib group, 71.6% of the lenvatinib-pembrolizumab group, and 73.0% of the lenvatinib-everolimus group. The higher rates with the combinations likely reflected longer treatment durations, according to Dr. Motzer.

The most common grade 3 or higher events with lenvatinib-pembrolizumab were hypertension (25.3%), diarrhea (8.2%), and proteinuria (7.4%). The most common grade 3 or higher events with lenvatinib-everolimus were hypertension (20.8%), hypertriglyceridemia (10.1%), and diarrhea (9.6%).

“The relatively low rates of hepatic toxicity, lack of myelosuppression, and low rate of high-grade hand-foot syndrome is an attractive feature for lenvatinib in combination,” Dr. Motzer said.
 

Which combination, which sequence?

“Lenvatinib plus pembrolizumab is another novel combination to have in our armamentarium now for first-line clear-cell RCC,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

CLEAR is the fourth positive trial of combination tyrosine kinase inhibitor therapy and immunotherapy in this setting, although findings and study populations differ somewhat, and longer follow-up is needed, she said.

“None of these combinations have been directly compared to one another, and I don’t believe they will be compared head to head,” Dr. Berg said. “But other characteristics – for example, health-related quality of life, familiarity of the agents for clinicians, and high tumor burden versus slow-growing disease – may become important to choose the best first-line option for our patients.”

The emerging first-line options also raise some questions about the optimal sequencing of agents, according to Dr. Berg.

“If one starts with combination immunotherapy, it becomes an automatic choice to use a VEGF tyrosine kinase inhibitor second line,” she elaborated. “These trials establish that immuno-oncology–tyrosine kinase inhibitor combination therapy is now standard of care, but our second-line choice is less clear. Therefore, data is needed on the most suitable order of therapy for the entire population, as well as specific groups in the future.”

The CLEAR trial was sponsored by Eisai Inc. and Merck Sharp & Dohme Corp. Dr. Motzer disclosed relationships with Eisai, Merck, and many other companies. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

The combination of lenvatinib and pembrolizumab outperforms sunitinib as first-line therapy for advanced clear-cell renal cell carcinoma (RCC), based on findings of the CLEAR trial.

Courtesy of Memorial Sloan Kettering Cancer Center

Results from the phase 3 trial were reported at the 2021 Genitourinary Cancers Symposium (Abstract 269) and simultaneously published in the New England Journal of Medicine.

Early-phase trials have shown the promise of targeting RCC from two angles, with both antiangiogenic therapy and immunotherapy, said presenter Robert J. Motzer, MD, of Memorial Sloan Kettering Cancer Center, New York.

The CLEAR trial was designed to compare monotherapy with sunitinib to treatment with lenvatinib plus either pembrolizumab or everolimus.

The risk of progression-free survival events was 61% lower with lenvatinib-pembrolizumab and 35% lower with lenvatinib-everolimus, compared with sunitinib. However, only the first combination significantly reduced the risk of death.

Treatment-related adverse events were more common with both combinations but manageable with dose modifications.

“These results support lenvatinib plus pembrolizumab as a potential first-line treatment for patients with advanced RCC,” Dr. Motzer said.

Oncologists will likely soon have a handful of first-line options from which to choose, he acknowledged.

“It is a great situation, that we have made such progress in RCC with IO [immuno-oncology] therapy in the first line with ipilimumab-nivolumab, and now with the IO-TKI [tyrosine kinase inhibitor] combinations,” Dr. Motzer said.

The choice will probably come down to personal preference, experience with the various combinations, and side effect profiles, he speculated.

“I will say, however, that the data with lenvatinib-pembrolizumab is very impressive in terms of the long progression-free survival, in terms of the doubling of response rate to over 70%, in terms of the 16% complete response rate,” he said.
 

Trial details

The CLEAR investigators evenly randomized 1,069 patients with advanced clear-cell RCC who had not received prior systemic therapy to treatment with lenvatinib-pembrolizumab, lenvatinib-everolimus, or sunitinib.

The primary analysis was conducted at a median follow-up of 27 months.

The median progression-free survival was 9.2 months with sunitinib, 23.9 months with lenvatinib-pembrolizumab (hazard ratio, 0.39; P < .001), and 14.7 months with lenvatinib-everolimus (HR for events, 0.65; P < .001).

Findings were similar across key subgroups, including International Metastatic RCC Database Consortium risk groups.

An interim analysis of overall survival showed that patients lived significantly longer with lenvatinib-pembrolizumab versus sunitinib (HR, 0.66; P = .005), with similar benefit across subgroups, except for the favorable risk group.

In contrast, lenvatinib-everolimus did not significantly improve overall survival (HR, 1.15; P = .3). The median overall survival was not reached in any treatment arm.

“To me, this emphasizes the role of IO therapy combinations in the first line. I think you need the IO in the first line to get the dramatic efficacy results that we saw in the CLEAR study,” Dr. Motzer said.

The confirmed objective response rate was 36.1% with sunitinib, 71.0% with lenvatinib-pembrolizumab (relative risk, 1.97; P < .001), and 53.5% with lenvatinib-everolimus (RR, 1.48; P <.001). The median duration of response was 14.6 months, 25.8 months, and 16.6 months, respectively.

Grade 3 or higher treatment-related adverse events occurred in 58.8% of patients in the sunitinib group, 71.6% of the lenvatinib-pembrolizumab group, and 73.0% of the lenvatinib-everolimus group. The higher rates with the combinations likely reflected longer treatment durations, according to Dr. Motzer.

The most common grade 3 or higher events with lenvatinib-pembrolizumab were hypertension (25.3%), diarrhea (8.2%), and proteinuria (7.4%). The most common grade 3 or higher events with lenvatinib-everolimus were hypertension (20.8%), hypertriglyceridemia (10.1%), and diarrhea (9.6%).

“The relatively low rates of hepatic toxicity, lack of myelosuppression, and low rate of high-grade hand-foot syndrome is an attractive feature for lenvatinib in combination,” Dr. Motzer said.
 

Which combination, which sequence?

“Lenvatinib plus pembrolizumab is another novel combination to have in our armamentarium now for first-line clear-cell RCC,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

CLEAR is the fourth positive trial of combination tyrosine kinase inhibitor therapy and immunotherapy in this setting, although findings and study populations differ somewhat, and longer follow-up is needed, she said.

“None of these combinations have been directly compared to one another, and I don’t believe they will be compared head to head,” Dr. Berg said. “But other characteristics – for example, health-related quality of life, familiarity of the agents for clinicians, and high tumor burden versus slow-growing disease – may become important to choose the best first-line option for our patients.”

The emerging first-line options also raise some questions about the optimal sequencing of agents, according to Dr. Berg.

“If one starts with combination immunotherapy, it becomes an automatic choice to use a VEGF tyrosine kinase inhibitor second line,” she elaborated. “These trials establish that immuno-oncology–tyrosine kinase inhibitor combination therapy is now standard of care, but our second-line choice is less clear. Therefore, data is needed on the most suitable order of therapy for the entire population, as well as specific groups in the future.”

The CLEAR trial was sponsored by Eisai Inc. and Merck Sharp & Dohme Corp. Dr. Motzer disclosed relationships with Eisai, Merck, and many other companies. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

The combination of lenvatinib and pembrolizumab outperforms sunitinib as first-line therapy for advanced clear-cell renal cell carcinoma (RCC), based on findings of the CLEAR trial.

Courtesy of Memorial Sloan Kettering Cancer Center

Results from the phase 3 trial were reported at the 2021 Genitourinary Cancers Symposium (Abstract 269) and simultaneously published in the New England Journal of Medicine.

Early-phase trials have shown the promise of targeting RCC from two angles, with both antiangiogenic therapy and immunotherapy, said presenter Robert J. Motzer, MD, of Memorial Sloan Kettering Cancer Center, New York.

The CLEAR trial was designed to compare monotherapy with sunitinib to treatment with lenvatinib plus either pembrolizumab or everolimus.

The risk of progression-free survival events was 61% lower with lenvatinib-pembrolizumab and 35% lower with lenvatinib-everolimus, compared with sunitinib. However, only the first combination significantly reduced the risk of death.

Treatment-related adverse events were more common with both combinations but manageable with dose modifications.

“These results support lenvatinib plus pembrolizumab as a potential first-line treatment for patients with advanced RCC,” Dr. Motzer said.

Oncologists will likely soon have a handful of first-line options from which to choose, he acknowledged.

“It is a great situation, that we have made such progress in RCC with IO [immuno-oncology] therapy in the first line with ipilimumab-nivolumab, and now with the IO-TKI [tyrosine kinase inhibitor] combinations,” Dr. Motzer said.

The choice will probably come down to personal preference, experience with the various combinations, and side effect profiles, he speculated.

“I will say, however, that the data with lenvatinib-pembrolizumab is very impressive in terms of the long progression-free survival, in terms of the doubling of response rate to over 70%, in terms of the 16% complete response rate,” he said.
 

Trial details

The CLEAR investigators evenly randomized 1,069 patients with advanced clear-cell RCC who had not received prior systemic therapy to treatment with lenvatinib-pembrolizumab, lenvatinib-everolimus, or sunitinib.

The primary analysis was conducted at a median follow-up of 27 months.

The median progression-free survival was 9.2 months with sunitinib, 23.9 months with lenvatinib-pembrolizumab (hazard ratio, 0.39; P < .001), and 14.7 months with lenvatinib-everolimus (HR for events, 0.65; P < .001).

Findings were similar across key subgroups, including International Metastatic RCC Database Consortium risk groups.

An interim analysis of overall survival showed that patients lived significantly longer with lenvatinib-pembrolizumab versus sunitinib (HR, 0.66; P = .005), with similar benefit across subgroups, except for the favorable risk group.

In contrast, lenvatinib-everolimus did not significantly improve overall survival (HR, 1.15; P = .3). The median overall survival was not reached in any treatment arm.

“To me, this emphasizes the role of IO therapy combinations in the first line. I think you need the IO in the first line to get the dramatic efficacy results that we saw in the CLEAR study,” Dr. Motzer said.

The confirmed objective response rate was 36.1% with sunitinib, 71.0% with lenvatinib-pembrolizumab (relative risk, 1.97; P < .001), and 53.5% with lenvatinib-everolimus (RR, 1.48; P <.001). The median duration of response was 14.6 months, 25.8 months, and 16.6 months, respectively.

Grade 3 or higher treatment-related adverse events occurred in 58.8% of patients in the sunitinib group, 71.6% of the lenvatinib-pembrolizumab group, and 73.0% of the lenvatinib-everolimus group. The higher rates with the combinations likely reflected longer treatment durations, according to Dr. Motzer.

The most common grade 3 or higher events with lenvatinib-pembrolizumab were hypertension (25.3%), diarrhea (8.2%), and proteinuria (7.4%). The most common grade 3 or higher events with lenvatinib-everolimus were hypertension (20.8%), hypertriglyceridemia (10.1%), and diarrhea (9.6%).

“The relatively low rates of hepatic toxicity, lack of myelosuppression, and low rate of high-grade hand-foot syndrome is an attractive feature for lenvatinib in combination,” Dr. Motzer said.
 

Which combination, which sequence?

“Lenvatinib plus pembrolizumab is another novel combination to have in our armamentarium now for first-line clear-cell RCC,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

CLEAR is the fourth positive trial of combination tyrosine kinase inhibitor therapy and immunotherapy in this setting, although findings and study populations differ somewhat, and longer follow-up is needed, she said.

“None of these combinations have been directly compared to one another, and I don’t believe they will be compared head to head,” Dr. Berg said. “But other characteristics – for example, health-related quality of life, familiarity of the agents for clinicians, and high tumor burden versus slow-growing disease – may become important to choose the best first-line option for our patients.”

The emerging first-line options also raise some questions about the optimal sequencing of agents, according to Dr. Berg.

“If one starts with combination immunotherapy, it becomes an automatic choice to use a VEGF tyrosine kinase inhibitor second line,” she elaborated. “These trials establish that immuno-oncology–tyrosine kinase inhibitor combination therapy is now standard of care, but our second-line choice is less clear. Therefore, data is needed on the most suitable order of therapy for the entire population, as well as specific groups in the future.”

The CLEAR trial was sponsored by Eisai Inc. and Merck Sharp & Dohme Corp. Dr. Motzer disclosed relationships with Eisai, Merck, and many other companies. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

When treating metastatic papillary renal cell carcinoma (RCC), cabozantinib outperforms the current standard of care, according to results from the Southwest Oncology Group (SWOG) 1500 trial.

Compared with the VEGFR-2 inhibitor sunitinib, the MET inhibitor cabozantinib improved both response rate and progression-free survival. Two other MET inhibitors, crizotinib and savolitinib, were not more efficacious than sunitinib.

“To date, there have been no randomized data specifically in papillary RCC showing an advantage of one systemic therapy over another,” said Sumanta K. Pal, MD, of City of Hope National Medical Center, Duarte, Calif., when presenting results from SWOG 1500.

Dr. Pal presented the results at the 2021 Genitourinary Cancers Symposium (Abstract 270), and they were published simultaneously in The Lancet.

The SWOG 1500 trial, also known as the PAPMET trial, was undertaken given evidence that signaling in the MET pathway is a driver in a sizable proportion of papillary RCCs, Dr. Pal explained.

Compared with sunitinib, cabozantinib reduced the risk of progression-free survival events by 40% and netted a response rate that was almost six times higher. On the other hand, the crizotinib and savolitinib arms of the trial were stopped early because of futility.

“Cabozantinib should be considered the new reference standard for systemic therapy in patients with metastatic papillary RCC,” Dr. Pal recommended. At present, VEGF-directed therapy is used as standard of care.

Dr. Pal noted that current evidence supports only monotherapy in papillary disease.

“There may be a temptation to put a patient on a combination of cabozantinib with immunotherapy, and certainly there is data in the context of clear-cell disease to support that. But we have to stop and think. We don’t know yet if that actually results in benefit for our patients, and obviously, it could extend the spectrum of toxicities that they incur,” he added.

Dr. Pal therefore encouraged oncologists and their patients with papillary RCC to consider the planned PAPMET-2 trial, which will explore the benefits and risks of adding immunotherapy to cabozantinib for this patient population.
 

SWOG 1500 details

The phase 2 SWOG 1500 trial was conducted in 65 U.S. and Canadian centers. It enrolled 152 patients with metastatic papillary RCC who had received up to one prior systemic therapy, excluding sunitinib. The trial is the first exclusively in this patient population to complete accrual, Dr. Pal noted.

Patients were randomized evenly to sunitinib, cabozantinib, crizotinib, or savolitinib.

The investigators stopped accrual to the savolitinib and crizotinib arms early based on a prespecified futility analysis showing that the hazard ratios for progression-free survival, compared with sunitinib, exceeded 1.

For the remaining arms, the median progression-free survival was 9.0 months with cabozantinib and 5.6 months with sunitinib (hazard ratio for events, 0.60; one-sided P = .019), meeting the trial’s primary endpoint. Subgroup analyses numerically favored cabozantinib in both type I and type II disease.

The confirmed overall response rate was 23% with cabozantinib and 4% with sunitinib (two-sided P = .010). Respective rates of complete response were 5% and 0%.

The median overall survival was 20.0 months with cabozantinib and 16.4 months with sunitinib, a nonsignificant difference.

The investigators are conducting exploratory analyses of MET mutational status and MET expression, and their associations with outcomes, according to Dr. Pal. Findings of other studies are suggesting that MET-altered papillary RCC may be a distinct entity, which would support genomically driven studies, he noted.

The rate of grade 3-4 toxicity was 68% in the sunitinib group, 74% in the cabozantinib group, 37% in the crizotinib group, and 39% in the savolitinib group. The types of toxicities seen were similar to those observed with each agent in larger trials, Dr. Pal observed.

There was a single grade 5 event, a death secondary to thromboembolism in the cabozantinib arm.
 

MET alterations may be key

“We should consider cabozantinib as another first-line option for papillary kidney cancer,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

Dr. Berg noted that the phase 3 SAVOIR trial, recently published in JAMA Oncology, compared savolitinib against sunitinib in MET-driven papillary RCC and stopped recruitment early. Although the trial did not meet its primary endpoint of progression-free survival, it did show numerically better results with the MET inhibitor.

“I question if the savolitinib arm in SWOG 1500 may have fared better if tumors were exclusively MET driven, especially as type II papillary patients represented almost half of the total patient population, and typically, 40% express alterations in MET,” Dr. Berg commented. “We will have to wait for further exploratory analysis regarding MET mutational status to tease out these differences.”

SWOG 1500 was sponsored by the National Cancer Institute. Dr. Pal disclosed a consulting or advisory role with Astellas Pharma, Aveo, Bristol-Myers Squibb, Eisai, Exelixis, Genentech, Ipsen, Myriad Pharmaceuticals, Novartis, and Pfizer. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

When treating metastatic papillary renal cell carcinoma (RCC), cabozantinib outperforms the current standard of care, according to results from the Southwest Oncology Group (SWOG) 1500 trial.

Compared with the VEGFR-2 inhibitor sunitinib, the MET inhibitor cabozantinib improved both response rate and progression-free survival. Two other MET inhibitors, crizotinib and savolitinib, were not more efficacious than sunitinib.

“To date, there have been no randomized data specifically in papillary RCC showing an advantage of one systemic therapy over another,” said Sumanta K. Pal, MD, of City of Hope National Medical Center, Duarte, Calif., when presenting results from SWOG 1500.

Dr. Pal presented the results at the 2021 Genitourinary Cancers Symposium (Abstract 270), and they were published simultaneously in The Lancet.

The SWOG 1500 trial, also known as the PAPMET trial, was undertaken given evidence that signaling in the MET pathway is a driver in a sizable proportion of papillary RCCs, Dr. Pal explained.

Compared with sunitinib, cabozantinib reduced the risk of progression-free survival events by 40% and netted a response rate that was almost six times higher. On the other hand, the crizotinib and savolitinib arms of the trial were stopped early because of futility.

“Cabozantinib should be considered the new reference standard for systemic therapy in patients with metastatic papillary RCC,” Dr. Pal recommended. At present, VEGF-directed therapy is used as standard of care.

Dr. Pal noted that current evidence supports only monotherapy in papillary disease.

“There may be a temptation to put a patient on a combination of cabozantinib with immunotherapy, and certainly there is data in the context of clear-cell disease to support that. But we have to stop and think. We don’t know yet if that actually results in benefit for our patients, and obviously, it could extend the spectrum of toxicities that they incur,” he added.

Dr. Pal therefore encouraged oncologists and their patients with papillary RCC to consider the planned PAPMET-2 trial, which will explore the benefits and risks of adding immunotherapy to cabozantinib for this patient population.
 

SWOG 1500 details

The phase 2 SWOG 1500 trial was conducted in 65 U.S. and Canadian centers. It enrolled 152 patients with metastatic papillary RCC who had received up to one prior systemic therapy, excluding sunitinib. The trial is the first exclusively in this patient population to complete accrual, Dr. Pal noted.

Patients were randomized evenly to sunitinib, cabozantinib, crizotinib, or savolitinib.

The investigators stopped accrual to the savolitinib and crizotinib arms early based on a prespecified futility analysis showing that the hazard ratios for progression-free survival, compared with sunitinib, exceeded 1.

For the remaining arms, the median progression-free survival was 9.0 months with cabozantinib and 5.6 months with sunitinib (hazard ratio for events, 0.60; one-sided P = .019), meeting the trial’s primary endpoint. Subgroup analyses numerically favored cabozantinib in both type I and type II disease.

The confirmed overall response rate was 23% with cabozantinib and 4% with sunitinib (two-sided P = .010). Respective rates of complete response were 5% and 0%.

The median overall survival was 20.0 months with cabozantinib and 16.4 months with sunitinib, a nonsignificant difference.

The investigators are conducting exploratory analyses of MET mutational status and MET expression, and their associations with outcomes, according to Dr. Pal. Findings of other studies are suggesting that MET-altered papillary RCC may be a distinct entity, which would support genomically driven studies, he noted.

The rate of grade 3-4 toxicity was 68% in the sunitinib group, 74% in the cabozantinib group, 37% in the crizotinib group, and 39% in the savolitinib group. The types of toxicities seen were similar to those observed with each agent in larger trials, Dr. Pal observed.

There was a single grade 5 event, a death secondary to thromboembolism in the cabozantinib arm.
 

MET alterations may be key

“We should consider cabozantinib as another first-line option for papillary kidney cancer,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

Dr. Berg noted that the phase 3 SAVOIR trial, recently published in JAMA Oncology, compared savolitinib against sunitinib in MET-driven papillary RCC and stopped recruitment early. Although the trial did not meet its primary endpoint of progression-free survival, it did show numerically better results with the MET inhibitor.

“I question if the savolitinib arm in SWOG 1500 may have fared better if tumors were exclusively MET driven, especially as type II papillary patients represented almost half of the total patient population, and typically, 40% express alterations in MET,” Dr. Berg commented. “We will have to wait for further exploratory analysis regarding MET mutational status to tease out these differences.”

SWOG 1500 was sponsored by the National Cancer Institute. Dr. Pal disclosed a consulting or advisory role with Astellas Pharma, Aveo, Bristol-Myers Squibb, Eisai, Exelixis, Genentech, Ipsen, Myriad Pharmaceuticals, Novartis, and Pfizer. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

When treating metastatic papillary renal cell carcinoma (RCC), cabozantinib outperforms the current standard of care, according to results from the Southwest Oncology Group (SWOG) 1500 trial.

Compared with the VEGFR-2 inhibitor sunitinib, the MET inhibitor cabozantinib improved both response rate and progression-free survival. Two other MET inhibitors, crizotinib and savolitinib, were not more efficacious than sunitinib.

“To date, there have been no randomized data specifically in papillary RCC showing an advantage of one systemic therapy over another,” said Sumanta K. Pal, MD, of City of Hope National Medical Center, Duarte, Calif., when presenting results from SWOG 1500.

Dr. Pal presented the results at the 2021 Genitourinary Cancers Symposium (Abstract 270), and they were published simultaneously in The Lancet.

The SWOG 1500 trial, also known as the PAPMET trial, was undertaken given evidence that signaling in the MET pathway is a driver in a sizable proportion of papillary RCCs, Dr. Pal explained.

Compared with sunitinib, cabozantinib reduced the risk of progression-free survival events by 40% and netted a response rate that was almost six times higher. On the other hand, the crizotinib and savolitinib arms of the trial were stopped early because of futility.

“Cabozantinib should be considered the new reference standard for systemic therapy in patients with metastatic papillary RCC,” Dr. Pal recommended. At present, VEGF-directed therapy is used as standard of care.

Dr. Pal noted that current evidence supports only monotherapy in papillary disease.

“There may be a temptation to put a patient on a combination of cabozantinib with immunotherapy, and certainly there is data in the context of clear-cell disease to support that. But we have to stop and think. We don’t know yet if that actually results in benefit for our patients, and obviously, it could extend the spectrum of toxicities that they incur,” he added.

Dr. Pal therefore encouraged oncologists and their patients with papillary RCC to consider the planned PAPMET-2 trial, which will explore the benefits and risks of adding immunotherapy to cabozantinib for this patient population.
 

SWOG 1500 details

The phase 2 SWOG 1500 trial was conducted in 65 U.S. and Canadian centers. It enrolled 152 patients with metastatic papillary RCC who had received up to one prior systemic therapy, excluding sunitinib. The trial is the first exclusively in this patient population to complete accrual, Dr. Pal noted.

Patients were randomized evenly to sunitinib, cabozantinib, crizotinib, or savolitinib.

The investigators stopped accrual to the savolitinib and crizotinib arms early based on a prespecified futility analysis showing that the hazard ratios for progression-free survival, compared with sunitinib, exceeded 1.

For the remaining arms, the median progression-free survival was 9.0 months with cabozantinib and 5.6 months with sunitinib (hazard ratio for events, 0.60; one-sided P = .019), meeting the trial’s primary endpoint. Subgroup analyses numerically favored cabozantinib in both type I and type II disease.

The confirmed overall response rate was 23% with cabozantinib and 4% with sunitinib (two-sided P = .010). Respective rates of complete response were 5% and 0%.

The median overall survival was 20.0 months with cabozantinib and 16.4 months with sunitinib, a nonsignificant difference.

The investigators are conducting exploratory analyses of MET mutational status and MET expression, and their associations with outcomes, according to Dr. Pal. Findings of other studies are suggesting that MET-altered papillary RCC may be a distinct entity, which would support genomically driven studies, he noted.

The rate of grade 3-4 toxicity was 68% in the sunitinib group, 74% in the cabozantinib group, 37% in the crizotinib group, and 39% in the savolitinib group. The types of toxicities seen were similar to those observed with each agent in larger trials, Dr. Pal observed.

There was a single grade 5 event, a death secondary to thromboembolism in the cabozantinib arm.
 

MET alterations may be key

“We should consider cabozantinib as another first-line option for papillary kidney cancer,” said invited discussant Stephanie A. Berg, DO, of Loyola University Medical Center in Maywood, Ill.

Courtesy of Loyola University

Dr. Berg noted that the phase 3 SAVOIR trial, recently published in JAMA Oncology, compared savolitinib against sunitinib in MET-driven papillary RCC and stopped recruitment early. Although the trial did not meet its primary endpoint of progression-free survival, it did show numerically better results with the MET inhibitor.

“I question if the savolitinib arm in SWOG 1500 may have fared better if tumors were exclusively MET driven, especially as type II papillary patients represented almost half of the total patient population, and typically, 40% express alterations in MET,” Dr. Berg commented. “We will have to wait for further exploratory analysis regarding MET mutational status to tease out these differences.”

SWOG 1500 was sponsored by the National Cancer Institute. Dr. Pal disclosed a consulting or advisory role with Astellas Pharma, Aveo, Bristol-Myers Squibb, Eisai, Exelixis, Genentech, Ipsen, Myriad Pharmaceuticals, Novartis, and Pfizer. Dr. Berg disclosed a consulting or advisory role with Bristol-Myers Squibb.

When early-stage seminoma metastasizes to one or two retroperitoneal lymph nodes, surgical excision is an “attractive” alternative to standard chemotherapy or radiation, according to an investigator from the phase 2 SEMS trial.

The trial enrolled 55 men with early-stage seminoma and isolated retroperitoneal disease, and all of them underwent retroperitoneal lymph node dissection (RPLND). At 2 years, the recurrence rate was 18%, the recurrence-free survival rate was 84%, and the overall survival rate was 100%. Surgical complications occurred in 13% of patients.

“The SEMS trial establishes RPLND as a first-line treatment alternative for testicular seminoma with isolated retroperitoneal lymphadenopathy up to 3 cm ... It’s an attractive option given the favorable long-term morbidity of RPLND,” said co-principal investigator Siamak Daneshmand, MD, of the University of Southern California (USC), Los Angeles.

“The whole point is to offer an alternative treatment that will avoid long-term toxicity ... It makes no sense treating isolated retroperitoneal lymphadenopathy with strong chemotherapy that’s meant for more widely disseminated disease,” Dr. Daneshmand said.

He presented results from the SEMS trial at the 2021 Genitourinary Cancers Symposium (Abstract 375).
 

Practice-changing?

Dr. Daneshmand called the trial results “practice-changing” and noted that surgery “makes sense” to patients and providers, especially because RPLND is already an established option for early-stage non-seminoma testicular cancer. In fact, USC has continued to offer RPLND for early-stage seminoma since this trial ended 2 years ago, Dr. Daneshmand said.

Study discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University in Turkey, offered a different viewpoint. She said the SEMS trial had an “excellent” design, but, due to the relatively short follow-up, she would recommend caution.

“We in Europe do not recommend primary retroperitoneal lymph node dissection in seminoma outside a trial or institutional study,” Dr. Laguna said.

Still, she said the SEMS trial “establishes a solid base” for ongoing prospective trials of primary RPLND in early-stage seminoma.
 

Trial details

The SEMS trial enrolled 55 patients with pure testicular seminoma. They had stage I disease with 1-3 cm relapse (25%) or stage IIA/B disease with no more than two lymph nodes in any dimension (75%). Imaging was done within 6 weeks of surgery to avoid under staging, and serum tumor markers could be no more than 1.5 times the upper limit of normal.

The majority of subjects were White, and the median age was 34 years (range, 21-64 years). Including USC, the trial was conducted at 12 North American sites.

Patients had open modified-template surgeries by surgeons who had performed at least eight open RPLNDs in 1 year or more than 24 in 3 years. Surgeries at USC used a midline approach, with a typical hospital stay of 1 day.

The median follow-up was 2 years. The overall recurrence rate was 18% (10/55), with a median time to recurrence of 8 months.

All 10 cases of recurrence were salvageable – 8 with chemotherapy and 2 with surgical resection. All of the recurrences were retroperitoneal.

“If you can cure 80% [of men] without radiation or chemotherapy, that’s very significant. These are young patients, and chemotherapy and radiation have long-term side effects. The important thing to remember is if men do recur, they are salvageable,” Dr. Daneshmand said.

Seven patients (13%) had surgical complications that were largely minor. The exceptions were one case of pulmonary embolism and one case of chylous ascites that required drainage. There were no long-term complications, including retrograde ejaculation.

The SEMS study was funded by the Think Different Foundation. Dr. Daneshmand and Dr. Laguna said they have no relevant disclosures.

aotto@mdedge.com

When early-stage seminoma metastasizes to one or two retroperitoneal lymph nodes, surgical excision is an “attractive” alternative to standard chemotherapy or radiation, according to an investigator from the phase 2 SEMS trial.

The trial enrolled 55 men with early-stage seminoma and isolated retroperitoneal disease, and all of them underwent retroperitoneal lymph node dissection (RPLND). At 2 years, the recurrence rate was 18%, the recurrence-free survival rate was 84%, and the overall survival rate was 100%. Surgical complications occurred in 13% of patients.

“The SEMS trial establishes RPLND as a first-line treatment alternative for testicular seminoma with isolated retroperitoneal lymphadenopathy up to 3 cm ... It’s an attractive option given the favorable long-term morbidity of RPLND,” said co-principal investigator Siamak Daneshmand, MD, of the University of Southern California (USC), Los Angeles.

“The whole point is to offer an alternative treatment that will avoid long-term toxicity ... It makes no sense treating isolated retroperitoneal lymphadenopathy with strong chemotherapy that’s meant for more widely disseminated disease,” Dr. Daneshmand said.

He presented results from the SEMS trial at the 2021 Genitourinary Cancers Symposium (Abstract 375).
 

Practice-changing?

Dr. Daneshmand called the trial results “practice-changing” and noted that surgery “makes sense” to patients and providers, especially because RPLND is already an established option for early-stage non-seminoma testicular cancer. In fact, USC has continued to offer RPLND for early-stage seminoma since this trial ended 2 years ago, Dr. Daneshmand said.

Study discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University in Turkey, offered a different viewpoint. She said the SEMS trial had an “excellent” design, but, due to the relatively short follow-up, she would recommend caution.

“We in Europe do not recommend primary retroperitoneal lymph node dissection in seminoma outside a trial or institutional study,” Dr. Laguna said.

Still, she said the SEMS trial “establishes a solid base” for ongoing prospective trials of primary RPLND in early-stage seminoma.
 

Trial details

The SEMS trial enrolled 55 patients with pure testicular seminoma. They had stage I disease with 1-3 cm relapse (25%) or stage IIA/B disease with no more than two lymph nodes in any dimension (75%). Imaging was done within 6 weeks of surgery to avoid under staging, and serum tumor markers could be no more than 1.5 times the upper limit of normal.

The majority of subjects were White, and the median age was 34 years (range, 21-64 years). Including USC, the trial was conducted at 12 North American sites.

Patients had open modified-template surgeries by surgeons who had performed at least eight open RPLNDs in 1 year or more than 24 in 3 years. Surgeries at USC used a midline approach, with a typical hospital stay of 1 day.

The median follow-up was 2 years. The overall recurrence rate was 18% (10/55), with a median time to recurrence of 8 months.

All 10 cases of recurrence were salvageable – 8 with chemotherapy and 2 with surgical resection. All of the recurrences were retroperitoneal.

“If you can cure 80% [of men] without radiation or chemotherapy, that’s very significant. These are young patients, and chemotherapy and radiation have long-term side effects. The important thing to remember is if men do recur, they are salvageable,” Dr. Daneshmand said.

Seven patients (13%) had surgical complications that were largely minor. The exceptions were one case of pulmonary embolism and one case of chylous ascites that required drainage. There were no long-term complications, including retrograde ejaculation.

The SEMS study was funded by the Think Different Foundation. Dr. Daneshmand and Dr. Laguna said they have no relevant disclosures.

aotto@mdedge.com

When early-stage seminoma metastasizes to one or two retroperitoneal lymph nodes, surgical excision is an “attractive” alternative to standard chemotherapy or radiation, according to an investigator from the phase 2 SEMS trial.

The trial enrolled 55 men with early-stage seminoma and isolated retroperitoneal disease, and all of them underwent retroperitoneal lymph node dissection (RPLND). At 2 years, the recurrence rate was 18%, the recurrence-free survival rate was 84%, and the overall survival rate was 100%. Surgical complications occurred in 13% of patients.

“The SEMS trial establishes RPLND as a first-line treatment alternative for testicular seminoma with isolated retroperitoneal lymphadenopathy up to 3 cm ... It’s an attractive option given the favorable long-term morbidity of RPLND,” said co-principal investigator Siamak Daneshmand, MD, of the University of Southern California (USC), Los Angeles.

“The whole point is to offer an alternative treatment that will avoid long-term toxicity ... It makes no sense treating isolated retroperitoneal lymphadenopathy with strong chemotherapy that’s meant for more widely disseminated disease,” Dr. Daneshmand said.

He presented results from the SEMS trial at the 2021 Genitourinary Cancers Symposium (Abstract 375).
 

Practice-changing?

Dr. Daneshmand called the trial results “practice-changing” and noted that surgery “makes sense” to patients and providers, especially because RPLND is already an established option for early-stage non-seminoma testicular cancer. In fact, USC has continued to offer RPLND for early-stage seminoma since this trial ended 2 years ago, Dr. Daneshmand said.

Study discussant Pilar Laguna, MD, PhD, of Istanbul Medipol University in Turkey, offered a different viewpoint. She said the SEMS trial had an “excellent” design, but, due to the relatively short follow-up, she would recommend caution.

“We in Europe do not recommend primary retroperitoneal lymph node dissection in seminoma outside a trial or institutional study,” Dr. Laguna said.

Still, she said the SEMS trial “establishes a solid base” for ongoing prospective trials of primary RPLND in early-stage seminoma.
 

Trial details

The SEMS trial enrolled 55 patients with pure testicular seminoma. They had stage I disease with 1-3 cm relapse (25%) or stage IIA/B disease with no more than two lymph nodes in any dimension (75%). Imaging was done within 6 weeks of surgery to avoid under staging, and serum tumor markers could be no more than 1.5 times the upper limit of normal.

The majority of subjects were White, and the median age was 34 years (range, 21-64 years). Including USC, the trial was conducted at 12 North American sites.

Patients had open modified-template surgeries by surgeons who had performed at least eight open RPLNDs in 1 year or more than 24 in 3 years. Surgeries at USC used a midline approach, with a typical hospital stay of 1 day.

The median follow-up was 2 years. The overall recurrence rate was 18% (10/55), with a median time to recurrence of 8 months.

All 10 cases of recurrence were salvageable – 8 with chemotherapy and 2 with surgical resection. All of the recurrences were retroperitoneal.

“If you can cure 80% [of men] without radiation or chemotherapy, that’s very significant. These are young patients, and chemotherapy and radiation have long-term side effects. The important thing to remember is if men do recur, they are salvageable,” Dr. Daneshmand said.

Seven patients (13%) had surgical complications that were largely minor. The exceptions were one case of pulmonary embolism and one case of chylous ascites that required drainage. There were no long-term complications, including retrograde ejaculation.

The SEMS study was funded by the Think Different Foundation. Dr. Daneshmand and Dr. Laguna said they have no relevant disclosures.

aotto@mdedge.com

The checkpoint inhibitor nivolumab is efficacious and well tolerated when used as adjuvant therapy in patients who have undergone radical surgery for high-risk muscle-invasive urothelial carcinoma (MIUC), first results of the CheckMate 274 trial suggest.

The trial enrolled patients regardless of tumor PD-L1 status and receipt of neoadjuvant chemotherapy. The median disease-free survival was 21.0 months among patients given adjuvant nivolumab, almost double the 10.9 months among counterparts given placebo. Unsurprisingly, treatment-related adverse events were more common with nivolumab, but health-related quality of life was similar to that with placebo.

“Nivolumab is the first systemic immunotherapy to demonstrate a statistically significant and clinically meaningful improvement in outcomes when administered as adjuvant therapy to patients with MIUC,” said study investigator Dean F. Bajorin, MD, of Memorial Sloan Kettering Cancer Center, New York.

“These results support nivolumab monotherapy as a new standard of care in the adjuvant setting for patients with high-risk MIUC after radical surgery regardless of PD-L1 status and prior neoadjuvant chemotherapy,” Dr. Bajorin said when presenting the results at the 2021 Genitourinary Cancers Symposium (Abstract 391).
 

Trial details

The international, phase 3 trial enrolled 709 patients who had undergone radical surgery for high-risk MIUC of the bladder, ureter, or renal pelvis.

By intention, about 20% of the trial population had upper-tract disease, Dr. Bajorin noted. Roughly 43% had received cisplatin-based neoadjuvant chemotherapy, and 40% had tumors that were positive for PD-L1 (defined as ≥1% expression).

The patients were randomized evenly to receive up to 1 year of adjuvant nivolumab or placebo on a double-blind basis.

At a median follow-up of about 20 months, the trial met its primary endpoint, showing significant prolongation of disease-free survival in the intention-to-treat population with nivolumab versus placebo – a median of 21.0 months and 10.9 months, respectively (hazard ratio, 0.70; P < .001).

In subgroup analyses by disease site, benefit appeared restricted to patients with bladder tumors, although this finding is only hypothesis generating, Dr. Bajorin said.

The gain in disease-free survival was greater when analysis was restricted to the patients whose tumors were positive for PD-L1. The median disease-free survival was not reached in the nivolumab group and was 10.8 months in the placebo group (HR, 0.53; P < .001).

Nivolumab also netted significantly better non–urothelial tract recurrence-free survival (an endpoint that excludes common, non–life-threatening second primary urothelial cancers) and distant metastasis–free survival, both in the entire intention-to-treat population and in the subset with PD-L1–positive tumors.

Patients in the nivolumab group had a higher rate of grade 3 or worse treatment-related adverse events (17.9% vs. 7.2%), mainly caused by higher rates of increased amylase levels and lipase levels. But there was no deterioration in health-related quality of life as compared with placebo.

The most common grade 3 or worse treatment-related adverse events with nivolumab that were potentially immune mediated were diarrhea (0.9%), colitis (0.9%), and pneumonitis (0.9%), including two deaths in patients with treatment-related pneumonitis.
 

Awaited findings

Overall survival and biomarker data will require longer follow-up, Dr. Bajorin acknowledged. He defended the choice of disease-free survival as the trial’s primary endpoint, noting that it was selected after discussions with regulators when the trial was designed about 7 years ago.

“We believe that disease-free survival is an appropriate endpoint, that there are a lot of symptoms associated with metastasis in this disease. This is a devastating, symptomatic disease when it’s metastatic,” he elaborated, adding that this fact was also a driver behind selection of the other efficacy endpoints.

“I think that, as we follow this study further, we will see that disease-free survival – like it has in other studies in urothelial cancer – can translate into an overall survival benefit as well,” Dr. Bajorin said.

“This study is one of the most important in the last 5 years,” commented session cochair James M. McKiernan, MD, of the Columbia University Irving Medical Center, New York.

Some questions do arise when comparing the trial’s findings against those of other adjuvant trials in MIUC, he observed in an interview. In addition, it was noteworthy that the benefit of nivolumab was greatest among patients with PD-L1–positive tumors and those who had received neoadjuvant cisplatin.

Nonetheless, “I agree with the overall conclusion of the trial, and these data will establish a new standard of care,” Dr. McKiernan concluded. “The absence of overall survival data is not concerning for me, but we will all await that endpoint.”

The trial was supported by Bristol-Myers Squibb. Dr. Bajorin disclosed relationships with Bristol-Myers Squibb and several other companies. Dr. McKiernan disclosed a relationship with miR Scientific.

The checkpoint inhibitor nivolumab is efficacious and well tolerated when used as adjuvant therapy in patients who have undergone radical surgery for high-risk muscle-invasive urothelial carcinoma (MIUC), first results of the CheckMate 274 trial suggest.

The trial enrolled patients regardless of tumor PD-L1 status and receipt of neoadjuvant chemotherapy. The median disease-free survival was 21.0 months among patients given adjuvant nivolumab, almost double the 10.9 months among counterparts given placebo. Unsurprisingly, treatment-related adverse events were more common with nivolumab, but health-related quality of life was similar to that with placebo.

“Nivolumab is the first systemic immunotherapy to demonstrate a statistically significant and clinically meaningful improvement in outcomes when administered as adjuvant therapy to patients with MIUC,” said study investigator Dean F. Bajorin, MD, of Memorial Sloan Kettering Cancer Center, New York.

“These results support nivolumab monotherapy as a new standard of care in the adjuvant setting for patients with high-risk MIUC after radical surgery regardless of PD-L1 status and prior neoadjuvant chemotherapy,” Dr. Bajorin said when presenting the results at the 2021 Genitourinary Cancers Symposium (Abstract 391).
 

Trial details

The international, phase 3 trial enrolled 709 patients who had undergone radical surgery for high-risk MIUC of the bladder, ureter, or renal pelvis.

By intention, about 20% of the trial population had upper-tract disease, Dr. Bajorin noted. Roughly 43% had received cisplatin-based neoadjuvant chemotherapy, and 40% had tumors that were positive for PD-L1 (defined as ≥1% expression).

The patients were randomized evenly to receive up to 1 year of adjuvant nivolumab or placebo on a double-blind basis.

At a median follow-up of about 20 months, the trial met its primary endpoint, showing significant prolongation of disease-free survival in the intention-to-treat population with nivolumab versus placebo – a median of 21.0 months and 10.9 months, respectively (hazard ratio, 0.70; P < .001).

In subgroup analyses by disease site, benefit appeared restricted to patients with bladder tumors, although this finding is only hypothesis generating, Dr. Bajorin said.

The gain in disease-free survival was greater when analysis was restricted to the patients whose tumors were positive for PD-L1. The median disease-free survival was not reached in the nivolumab group and was 10.8 months in the placebo group (HR, 0.53; P < .001).

Nivolumab also netted significantly better non–urothelial tract recurrence-free survival (an endpoint that excludes common, non–life-threatening second primary urothelial cancers) and distant metastasis–free survival, both in the entire intention-to-treat population and in the subset with PD-L1–positive tumors.

Patients in the nivolumab group had a higher rate of grade 3 or worse treatment-related adverse events (17.9% vs. 7.2%), mainly caused by higher rates of increased amylase levels and lipase levels. But there was no deterioration in health-related quality of life as compared with placebo.

The most common grade 3 or worse treatment-related adverse events with nivolumab that were potentially immune mediated were diarrhea (0.9%), colitis (0.9%), and pneumonitis (0.9%), including two deaths in patients with treatment-related pneumonitis.
 

Awaited findings

Overall survival and biomarker data will require longer follow-up, Dr. Bajorin acknowledged. He defended the choice of disease-free survival as the trial’s primary endpoint, noting that it was selected after discussions with regulators when the trial was designed about 7 years ago.

“We believe that disease-free survival is an appropriate endpoint, that there are a lot of symptoms associated with metastasis in this disease. This is a devastating, symptomatic disease when it’s metastatic,” he elaborated, adding that this fact was also a driver behind selection of the other efficacy endpoints.

“I think that, as we follow this study further, we will see that disease-free survival – like it has in other studies in urothelial cancer – can translate into an overall survival benefit as well,” Dr. Bajorin said.

“This study is one of the most important in the last 5 years,” commented session cochair James M. McKiernan, MD, of the Columbia University Irving Medical Center, New York.

Some questions do arise when comparing the trial’s findings against those of other adjuvant trials in MIUC, he observed in an interview. In addition, it was noteworthy that the benefit of nivolumab was greatest among patients with PD-L1–positive tumors and those who had received neoadjuvant cisplatin.

Nonetheless, “I agree with the overall conclusion of the trial, and these data will establish a new standard of care,” Dr. McKiernan concluded. “The absence of overall survival data is not concerning for me, but we will all await that endpoint.”

The trial was supported by Bristol-Myers Squibb. Dr. Bajorin disclosed relationships with Bristol-Myers Squibb and several other companies. Dr. McKiernan disclosed a relationship with miR Scientific.

The checkpoint inhibitor nivolumab is efficacious and well tolerated when used as adjuvant therapy in patients who have undergone radical surgery for high-risk muscle-invasive urothelial carcinoma (MIUC), first results of the CheckMate 274 trial suggest.

The trial enrolled patients regardless of tumor PD-L1 status and receipt of neoadjuvant chemotherapy. The median disease-free survival was 21.0 months among patients given adjuvant nivolumab, almost double the 10.9 months among counterparts given placebo. Unsurprisingly, treatment-related adverse events were more common with nivolumab, but health-related quality of life was similar to that with placebo.

“Nivolumab is the first systemic immunotherapy to demonstrate a statistically significant and clinically meaningful improvement in outcomes when administered as adjuvant therapy to patients with MIUC,” said study investigator Dean F. Bajorin, MD, of Memorial Sloan Kettering Cancer Center, New York.

“These results support nivolumab monotherapy as a new standard of care in the adjuvant setting for patients with high-risk MIUC after radical surgery regardless of PD-L1 status and prior neoadjuvant chemotherapy,” Dr. Bajorin said when presenting the results at the 2021 Genitourinary Cancers Symposium (Abstract 391).
 

Trial details

The international, phase 3 trial enrolled 709 patients who had undergone radical surgery for high-risk MIUC of the bladder, ureter, or renal pelvis.

By intention, about 20% of the trial population had upper-tract disease, Dr. Bajorin noted. Roughly 43% had received cisplatin-based neoadjuvant chemotherapy, and 40% had tumors that were positive for PD-L1 (defined as ≥1% expression).

The patients were randomized evenly to receive up to 1 year of adjuvant nivolumab or placebo on a double-blind basis.

At a median follow-up of about 20 months, the trial met its primary endpoint, showing significant prolongation of disease-free survival in the intention-to-treat population with nivolumab versus placebo – a median of 21.0 months and 10.9 months, respectively (hazard ratio, 0.70; P < .001).

In subgroup analyses by disease site, benefit appeared restricted to patients with bladder tumors, although this finding is only hypothesis generating, Dr. Bajorin said.

The gain in disease-free survival was greater when analysis was restricted to the patients whose tumors were positive for PD-L1. The median disease-free survival was not reached in the nivolumab group and was 10.8 months in the placebo group (HR, 0.53; P < .001).

Nivolumab also netted significantly better non–urothelial tract recurrence-free survival (an endpoint that excludes common, non–life-threatening second primary urothelial cancers) and distant metastasis–free survival, both in the entire intention-to-treat population and in the subset with PD-L1–positive tumors.

Patients in the nivolumab group had a higher rate of grade 3 or worse treatment-related adverse events (17.9% vs. 7.2%), mainly caused by higher rates of increased amylase levels and lipase levels. But there was no deterioration in health-related quality of life as compared with placebo.

The most common grade 3 or worse treatment-related adverse events with nivolumab that were potentially immune mediated were diarrhea (0.9%), colitis (0.9%), and pneumonitis (0.9%), including two deaths in patients with treatment-related pneumonitis.
 

Awaited findings

Overall survival and biomarker data will require longer follow-up, Dr. Bajorin acknowledged. He defended the choice of disease-free survival as the trial’s primary endpoint, noting that it was selected after discussions with regulators when the trial was designed about 7 years ago.

“We believe that disease-free survival is an appropriate endpoint, that there are a lot of symptoms associated with metastasis in this disease. This is a devastating, symptomatic disease when it’s metastatic,” he elaborated, adding that this fact was also a driver behind selection of the other efficacy endpoints.

“I think that, as we follow this study further, we will see that disease-free survival – like it has in other studies in urothelial cancer – can translate into an overall survival benefit as well,” Dr. Bajorin said.

“This study is one of the most important in the last 5 years,” commented session cochair James M. McKiernan, MD, of the Columbia University Irving Medical Center, New York.

Some questions do arise when comparing the trial’s findings against those of other adjuvant trials in MIUC, he observed in an interview. In addition, it was noteworthy that the benefit of nivolumab was greatest among patients with PD-L1–positive tumors and those who had received neoadjuvant cisplatin.

Nonetheless, “I agree with the overall conclusion of the trial, and these data will establish a new standard of care,” Dr. McKiernan concluded. “The absence of overall survival data is not concerning for me, but we will all await that endpoint.”

The trial was supported by Bristol-Myers Squibb. Dr. Bajorin disclosed relationships with Bristol-Myers Squibb and several other companies. Dr. McKiernan disclosed a relationship with miR Scientific.

The survival benefit of adding apalutamide to standard care for metastatic castration-sensitive prostate cancer persisted at nearly 4 years of follow-up, according to the final analysis of the phase 3 TITAN trial.

At a median follow-up of 44 months, the median overall survival (OS) was not reached in patients who received apalutamide plus standard androgen deprivation therapy (ADT), but the median OS was 52.2 months in patients who received placebo plus ADT.

“In the final analysis, the risk of death with apalutamide was reduced by 35%, with a hazard ratio of 0.65 and P value of less than .0001. This was similar to the hazard ratio of 0.67 in the primary analysis of TITAN, despite an almost 40% crossover rate from the placebo group to the apalutamide,” said Kim N. Chi, MD, a medical oncologist at BC Cancer Vancouver Prostate Centre.

Dr. Chi reported these results at the 2021 Genitourinary Cancer Symposium (Abstract 11).
 

Study details

The international, double-blind TITAN trial compared apalutamide (240 mg daily) with placebo, both added to standard ADT, in 1,052 patients with metastatic castration-sensitive prostate cancer, including those with high- and low-volume disease, prior docetaxel use, prior treatment for localized disease, and prior ADT for no more than 6 months.

At the primary analysis, reported in the New England Journal of Medicine in 2019, the dual primary endpoints of radiographic progression-free survival and OS met statistical significance at a median follow up of 22.7 months.

At the final analysis, the median treatment duration was 39.3 months for the apalutamide arm, 20.2 months for the placebo arm, and 15.4 months for patients who crossed over from placebo to apalutamide.

After adjusting for crossover, the effect of apalutamide on OS increased (HR, 0.52), indicating a reduction in the risk of death by 48% versus placebo, Dr. Chi said. He noted that the treatment effect on OS favored apalutamide in both high- and low-volume disease.

“Treatment with apalutamide also significantly prolonged second progression-free survival on next subsequent therapy and delayed development of castration resistance,” Dr. Chi said.

The median second progression-free survival was 44.0 months in the placebo arm and was not reached in the apalutamide arm. The median time to castration resistance was 11.4 months in the placebo arm and was not reached in the apalutamide arm.

Health-related quality of life was also maintained in the apalutamide group throughout the study and did not differ from the placebo group. Safety was consistent with previous reports.

“Importantly, the cumulative incidence of treatment-related falls, fracture, and fatigue was similar between groups, as was the cumulative incidence of treatment-related adverse events and serious adverse events,” Dr. Chi said.

An increased incidence of any-grade rash that was seen in the apalutamide group was expected but plateaued after about 6 months.

“These results confirm the favorable risk-benefit profile of apalutamide,” Dr. Chi concluded.
 

Implications for practice

The study results raise questions about how to best incorporate the findings into practice, including how to use docetaxel or other androgen receptor inhibitors in treatment strategies for this patient population and if they should be used in high-volume patients, said Elisabeth Heath, MD, session cochair and associate director of translational science at Wayne State University in Detroit.

Dr. Chi said a number of studies over the past 5 years have demonstrated OS benefit when combining ADT with additional therapy.

“Really, this should be considered the standard of care,” he said. “However, real-world studies ... suggest that only a minority of patients are actually receiving this additional therapy.”

Although there are challenges with comparing outcomes across studies to determine which treatments to use, the TITAN data reinforce apalutamide plus ADT as a good option, including in high-volume patients, Dr. Chi said.

Funding for TITAN was provided by Janssen Research & Development. Dr. Chi and Dr. Heath disclosed relationships with Janssen and many other companies. sworcester@mdedge.com
 

The survival benefit of adding apalutamide to standard care for metastatic castration-sensitive prostate cancer persisted at nearly 4 years of follow-up, according to the final analysis of the phase 3 TITAN trial.

At a median follow-up of 44 months, the median overall survival (OS) was not reached in patients who received apalutamide plus standard androgen deprivation therapy (ADT), but the median OS was 52.2 months in patients who received placebo plus ADT.

“In the final analysis, the risk of death with apalutamide was reduced by 35%, with a hazard ratio of 0.65 and P value of less than .0001. This was similar to the hazard ratio of 0.67 in the primary analysis of TITAN, despite an almost 40% crossover rate from the placebo group to the apalutamide,” said Kim N. Chi, MD, a medical oncologist at BC Cancer Vancouver Prostate Centre.

Dr. Chi reported these results at the 2021 Genitourinary Cancer Symposium (Abstract 11).
 

Study details

The international, double-blind TITAN trial compared apalutamide (240 mg daily) with placebo, both added to standard ADT, in 1,052 patients with metastatic castration-sensitive prostate cancer, including those with high- and low-volume disease, prior docetaxel use, prior treatment for localized disease, and prior ADT for no more than 6 months.

At the primary analysis, reported in the New England Journal of Medicine in 2019, the dual primary endpoints of radiographic progression-free survival and OS met statistical significance at a median follow up of 22.7 months.

At the final analysis, the median treatment duration was 39.3 months for the apalutamide arm, 20.2 months for the placebo arm, and 15.4 months for patients who crossed over from placebo to apalutamide.

After adjusting for crossover, the effect of apalutamide on OS increased (HR, 0.52), indicating a reduction in the risk of death by 48% versus placebo, Dr. Chi said. He noted that the treatment effect on OS favored apalutamide in both high- and low-volume disease.

“Treatment with apalutamide also significantly prolonged second progression-free survival on next subsequent therapy and delayed development of castration resistance,” Dr. Chi said.

The median second progression-free survival was 44.0 months in the placebo arm and was not reached in the apalutamide arm. The median time to castration resistance was 11.4 months in the placebo arm and was not reached in the apalutamide arm.

Health-related quality of life was also maintained in the apalutamide group throughout the study and did not differ from the placebo group. Safety was consistent with previous reports.

“Importantly, the cumulative incidence of treatment-related falls, fracture, and fatigue was similar between groups, as was the cumulative incidence of treatment-related adverse events and serious adverse events,” Dr. Chi said.

An increased incidence of any-grade rash that was seen in the apalutamide group was expected but plateaued after about 6 months.

“These results confirm the favorable risk-benefit profile of apalutamide,” Dr. Chi concluded.
 

Implications for practice

The study results raise questions about how to best incorporate the findings into practice, including how to use docetaxel or other androgen receptor inhibitors in treatment strategies for this patient population and if they should be used in high-volume patients, said Elisabeth Heath, MD, session cochair and associate director of translational science at Wayne State University in Detroit.

Dr. Chi said a number of studies over the past 5 years have demonstrated OS benefit when combining ADT with additional therapy.

“Really, this should be considered the standard of care,” he said. “However, real-world studies ... suggest that only a minority of patients are actually receiving this additional therapy.”

Although there are challenges with comparing outcomes across studies to determine which treatments to use, the TITAN data reinforce apalutamide plus ADT as a good option, including in high-volume patients, Dr. Chi said.

Funding for TITAN was provided by Janssen Research & Development. Dr. Chi and Dr. Heath disclosed relationships with Janssen and many other companies. sworcester@mdedge.com
 

The survival benefit of adding apalutamide to standard care for metastatic castration-sensitive prostate cancer persisted at nearly 4 years of follow-up, according to the final analysis of the phase 3 TITAN trial.

At a median follow-up of 44 months, the median overall survival (OS) was not reached in patients who received apalutamide plus standard androgen deprivation therapy (ADT), but the median OS was 52.2 months in patients who received placebo plus ADT.

“In the final analysis, the risk of death with apalutamide was reduced by 35%, with a hazard ratio of 0.65 and P value of less than .0001. This was similar to the hazard ratio of 0.67 in the primary analysis of TITAN, despite an almost 40% crossover rate from the placebo group to the apalutamide,” said Kim N. Chi, MD, a medical oncologist at BC Cancer Vancouver Prostate Centre.

Dr. Chi reported these results at the 2021 Genitourinary Cancer Symposium (Abstract 11).
 

Study details

The international, double-blind TITAN trial compared apalutamide (240 mg daily) with placebo, both added to standard ADT, in 1,052 patients with metastatic castration-sensitive prostate cancer, including those with high- and low-volume disease, prior docetaxel use, prior treatment for localized disease, and prior ADT for no more than 6 months.

At the primary analysis, reported in the New England Journal of Medicine in 2019, the dual primary endpoints of radiographic progression-free survival and OS met statistical significance at a median follow up of 22.7 months.

At the final analysis, the median treatment duration was 39.3 months for the apalutamide arm, 20.2 months for the placebo arm, and 15.4 months for patients who crossed over from placebo to apalutamide.

After adjusting for crossover, the effect of apalutamide on OS increased (HR, 0.52), indicating a reduction in the risk of death by 48% versus placebo, Dr. Chi said. He noted that the treatment effect on OS favored apalutamide in both high- and low-volume disease.

“Treatment with apalutamide also significantly prolonged second progression-free survival on next subsequent therapy and delayed development of castration resistance,” Dr. Chi said.

The median second progression-free survival was 44.0 months in the placebo arm and was not reached in the apalutamide arm. The median time to castration resistance was 11.4 months in the placebo arm and was not reached in the apalutamide arm.

Health-related quality of life was also maintained in the apalutamide group throughout the study and did not differ from the placebo group. Safety was consistent with previous reports.

“Importantly, the cumulative incidence of treatment-related falls, fracture, and fatigue was similar between groups, as was the cumulative incidence of treatment-related adverse events and serious adverse events,” Dr. Chi said.

An increased incidence of any-grade rash that was seen in the apalutamide group was expected but plateaued after about 6 months.

“These results confirm the favorable risk-benefit profile of apalutamide,” Dr. Chi concluded.
 

Implications for practice

The study results raise questions about how to best incorporate the findings into practice, including how to use docetaxel or other androgen receptor inhibitors in treatment strategies for this patient population and if they should be used in high-volume patients, said Elisabeth Heath, MD, session cochair and associate director of translational science at Wayne State University in Detroit.

Dr. Chi said a number of studies over the past 5 years have demonstrated OS benefit when combining ADT with additional therapy.

“Really, this should be considered the standard of care,” he said. “However, real-world studies ... suggest that only a minority of patients are actually receiving this additional therapy.”

Although there are challenges with comparing outcomes across studies to determine which treatments to use, the TITAN data reinforce apalutamide plus ADT as a good option, including in high-volume patients, Dr. Chi said.

Funding for TITAN was provided by Janssen Research & Development. Dr. Chi and Dr. Heath disclosed relationships with Janssen and many other companies. sworcester@mdedge.com
 

The combined clinical cell-cycle risk (CCR) score – derived from both clinical and genetic factors – can identify patients with intermediate- and high-risk localized prostate cancer who could potentially forgo androgen deprivation therapy (ADT), a retrospective study suggests.

The score can identify patients in whom the risk of metastasis after dose-escalated radiation is so small that adding ADT no longer makes clinical sense, according to investigator Jonathan Tward, MD, PhD, of the Genitourinary Cancer Center at the University of Utah, Salt Lake City.

His group’s study, which included 741 patients, showed that, below a CCR score of 2.112, the 10-year risk of metastasis was 4.2% with radiation therapy (RT) alone and 3.9% with the addition of ADT.

“Whether you have RT alone, RT plus any duration of ADT, insufficient duration ADT, or sufficient ADT duration by guideline standard, the risk of metastasis never exceeds 5% at 10 years” even in high- and very-high-risk men, Dr. Tward said.

He and his team found that half the men in their study with unfavorable intermediate-risk disease, 20% with high-risk disease, and 5% with very-high-risk disease scored below the CCR threshold.

This implies that, for many men, ADT after radiation “adds unnecessary morbidity for an extremely small absolute risk reduction in metastasis-free survival,” Dr. Tward said at the 2021 Genitourinary Cancers Symposium, where he presented the findings (Abstract 195).
 

Value of CCR

The CCR score tells you if the relative metastasis risk reduction with ADT after radiation – about 50% based on clinical trials – translates to an absolute risk reduction that would matter, Dr. Tward said in an interview.

“Each patient has in their own mind what that risk reduction is that works for them,” he added.

For some patients, a 1%-2% drop in absolute risk is worth it, he said, but most patients wouldn’t be willing to endure the side effects of hormone therapy if the absolute benefit is less than 5%.

The CCR score is a validated prognosticator of metastasis and death in localized prostate cancer. It’s an amalgam of traditional clinical risk factors from the Cancer of the Prostate Risk Assessment (CAPRA) score and the cell-cycle progression (CCP) score, which measures expression of cell-cycle proliferation genes for a sense of how quickly tumor cells are dividing.

The CCP test is available commercially as Prolaris. It is used mostly to make the call between active surveillance and treatment, Dr. Tward explained, “but I had a hunch this off-the-shelf test would be very good at” helping with ADT decisions after radiation.
 

‘Uncomfortable’ findings, barriers to acceptance

“People are going to be very uncomfortable with these findings because it’s been ingrained in our heads for the past 20-30 years that you must use hormone therapy with high-risk prostate cancer, and you should use hormone therapy with intermediate risk,” Dr. Tward said.

“It took me a while to believe my own data, but we have used this test for several years to help men decide if they would like to have hormone therapy after radiation. Patients clearly benefit from this information,” he said.

The 2.112 cut point for CCR was determined from a prior study that was presented at GUCS 2020 (Abstract 346) and recently accepted for publication.

In the validation study Dr. Tward presented at GUCS 2021, 70% of patients had intermediate-risk disease, and 30% had high- or very-high-risk disease according to National Comprehensive Cancer Network criteria.

All 741 patients received RT equivalent to at least 75.6 Gy at 1.8 Gy per fraction, with 84% getting or exceeding 79.2 Gy. About half the men (53%) had ADT after RT.

Genetic testing was done on stored biopsy samples years after the men were treated. Half of them were below the CCR threshold of 2.112. For those above it, the 10-year risk of metastasis was 25.3%.

CCR outperformed CCP alone, CAPRA alone, and NCCN risk groupings for predicting metastasis risk after RT.

Though this validation study was “successful,” additional research is needed, according to study discussant Richard Valicenti, MD, of the University of California, Davis.

“Widespread acceptance for routine use faces challenges since no biomarker has been prospectively tested or shown to improve long-term outcome,” Dr. Valicenti said. “Clearly, the CCR score may provide highly precise, personalized estimates and justifies testing in tiered and appropriately powered noninferiority studies according to NCCN risk groups. We eagerly await the completion and reporting of such trials so that we have a more personalized approach to treating men with prostate cancer.”

The current study was funded by Myriad Genetics, the company that developed the Prolaris test. Dr. Tward disclosed relationships with Myriad Genetics, Bayer, Blue Earth Diagnostics, Janssen Scientific Affairs, and Merck. Dr. Valicenti has no disclosures.

aotto@mdedge.com

The combined clinical cell-cycle risk (CCR) score – derived from both clinical and genetic factors – can identify patients with intermediate- and high-risk localized prostate cancer who could potentially forgo androgen deprivation therapy (ADT), a retrospective study suggests.

The score can identify patients in whom the risk of metastasis after dose-escalated radiation is so small that adding ADT no longer makes clinical sense, according to investigator Jonathan Tward, MD, PhD, of the Genitourinary Cancer Center at the University of Utah, Salt Lake City.

His group’s study, which included 741 patients, showed that, below a CCR score of 2.112, the 10-year risk of metastasis was 4.2% with radiation therapy (RT) alone and 3.9% with the addition of ADT.

“Whether you have RT alone, RT plus any duration of ADT, insufficient duration ADT, or sufficient ADT duration by guideline standard, the risk of metastasis never exceeds 5% at 10 years” even in high- and very-high-risk men, Dr. Tward said.

He and his team found that half the men in their study with unfavorable intermediate-risk disease, 20% with high-risk disease, and 5% with very-high-risk disease scored below the CCR threshold.

This implies that, for many men, ADT after radiation “adds unnecessary morbidity for an extremely small absolute risk reduction in metastasis-free survival,” Dr. Tward said at the 2021 Genitourinary Cancers Symposium, where he presented the findings (Abstract 195).
 

Value of CCR

The CCR score tells you if the relative metastasis risk reduction with ADT after radiation – about 50% based on clinical trials – translates to an absolute risk reduction that would matter, Dr. Tward said in an interview.

“Each patient has in their own mind what that risk reduction is that works for them,” he added.

For some patients, a 1%-2% drop in absolute risk is worth it, he said, but most patients wouldn’t be willing to endure the side effects of hormone therapy if the absolute benefit is less than 5%.

The CCR score is a validated prognosticator of metastasis and death in localized prostate cancer. It’s an amalgam of traditional clinical risk factors from the Cancer of the Prostate Risk Assessment (CAPRA) score and the cell-cycle progression (CCP) score, which measures expression of cell-cycle proliferation genes for a sense of how quickly tumor cells are dividing.

The CCP test is available commercially as Prolaris. It is used mostly to make the call between active surveillance and treatment, Dr. Tward explained, “but I had a hunch this off-the-shelf test would be very good at” helping with ADT decisions after radiation.
 

‘Uncomfortable’ findings, barriers to acceptance

“People are going to be very uncomfortable with these findings because it’s been ingrained in our heads for the past 20-30 years that you must use hormone therapy with high-risk prostate cancer, and you should use hormone therapy with intermediate risk,” Dr. Tward said.

“It took me a while to believe my own data, but we have used this test for several years to help men decide if they would like to have hormone therapy after radiation. Patients clearly benefit from this information,” he said.

The 2.112 cut point for CCR was determined from a prior study that was presented at GUCS 2020 (Abstract 346) and recently accepted for publication.

In the validation study Dr. Tward presented at GUCS 2021, 70% of patients had intermediate-risk disease, and 30% had high- or very-high-risk disease according to National Comprehensive Cancer Network criteria.

All 741 patients received RT equivalent to at least 75.6 Gy at 1.8 Gy per fraction, with 84% getting or exceeding 79.2 Gy. About half the men (53%) had ADT after RT.

Genetic testing was done on stored biopsy samples years after the men were treated. Half of them were below the CCR threshold of 2.112. For those above it, the 10-year risk of metastasis was 25.3%.

CCR outperformed CCP alone, CAPRA alone, and NCCN risk groupings for predicting metastasis risk after RT.

Though this validation study was “successful,” additional research is needed, according to study discussant Richard Valicenti, MD, of the University of California, Davis.

“Widespread acceptance for routine use faces challenges since no biomarker has been prospectively tested or shown to improve long-term outcome,” Dr. Valicenti said. “Clearly, the CCR score may provide highly precise, personalized estimates and justifies testing in tiered and appropriately powered noninferiority studies according to NCCN risk groups. We eagerly await the completion and reporting of such trials so that we have a more personalized approach to treating men with prostate cancer.”

The current study was funded by Myriad Genetics, the company that developed the Prolaris test. Dr. Tward disclosed relationships with Myriad Genetics, Bayer, Blue Earth Diagnostics, Janssen Scientific Affairs, and Merck. Dr. Valicenti has no disclosures.

aotto@mdedge.com

The combined clinical cell-cycle risk (CCR) score – derived from both clinical and genetic factors – can identify patients with intermediate- and high-risk localized prostate cancer who could potentially forgo androgen deprivation therapy (ADT), a retrospective study suggests.

The score can identify patients in whom the risk of metastasis after dose-escalated radiation is so small that adding ADT no longer makes clinical sense, according to investigator Jonathan Tward, MD, PhD, of the Genitourinary Cancer Center at the University of Utah, Salt Lake City.

His group’s study, which included 741 patients, showed that, below a CCR score of 2.112, the 10-year risk of metastasis was 4.2% with radiation therapy (RT) alone and 3.9% with the addition of ADT.

“Whether you have RT alone, RT plus any duration of ADT, insufficient duration ADT, or sufficient ADT duration by guideline standard, the risk of metastasis never exceeds 5% at 10 years” even in high- and very-high-risk men, Dr. Tward said.

He and his team found that half the men in their study with unfavorable intermediate-risk disease, 20% with high-risk disease, and 5% with very-high-risk disease scored below the CCR threshold.

This implies that, for many men, ADT after radiation “adds unnecessary morbidity for an extremely small absolute risk reduction in metastasis-free survival,” Dr. Tward said at the 2021 Genitourinary Cancers Symposium, where he presented the findings (Abstract 195).
 

Value of CCR

The CCR score tells you if the relative metastasis risk reduction with ADT after radiation – about 50% based on clinical trials – translates to an absolute risk reduction that would matter, Dr. Tward said in an interview.

“Each patient has in their own mind what that risk reduction is that works for them,” he added.

For some patients, a 1%-2% drop in absolute risk is worth it, he said, but most patients wouldn’t be willing to endure the side effects of hormone therapy if the absolute benefit is less than 5%.

The CCR score is a validated prognosticator of metastasis and death in localized prostate cancer. It’s an amalgam of traditional clinical risk factors from the Cancer of the Prostate Risk Assessment (CAPRA) score and the cell-cycle progression (CCP) score, which measures expression of cell-cycle proliferation genes for a sense of how quickly tumor cells are dividing.

The CCP test is available commercially as Prolaris. It is used mostly to make the call between active surveillance and treatment, Dr. Tward explained, “but I had a hunch this off-the-shelf test would be very good at” helping with ADT decisions after radiation.
 

‘Uncomfortable’ findings, barriers to acceptance

“People are going to be very uncomfortable with these findings because it’s been ingrained in our heads for the past 20-30 years that you must use hormone therapy with high-risk prostate cancer, and you should use hormone therapy with intermediate risk,” Dr. Tward said.

“It took me a while to believe my own data, but we have used this test for several years to help men decide if they would like to have hormone therapy after radiation. Patients clearly benefit from this information,” he said.

The 2.112 cut point for CCR was determined from a prior study that was presented at GUCS 2020 (Abstract 346) and recently accepted for publication.

In the validation study Dr. Tward presented at GUCS 2021, 70% of patients had intermediate-risk disease, and 30% had high- or very-high-risk disease according to National Comprehensive Cancer Network criteria.

All 741 patients received RT equivalent to at least 75.6 Gy at 1.8 Gy per fraction, with 84% getting or exceeding 79.2 Gy. About half the men (53%) had ADT after RT.

Genetic testing was done on stored biopsy samples years after the men were treated. Half of them were below the CCR threshold of 2.112. For those above it, the 10-year risk of metastasis was 25.3%.

CCR outperformed CCP alone, CAPRA alone, and NCCN risk groupings for predicting metastasis risk after RT.

Though this validation study was “successful,” additional research is needed, according to study discussant Richard Valicenti, MD, of the University of California, Davis.

“Widespread acceptance for routine use faces challenges since no biomarker has been prospectively tested or shown to improve long-term outcome,” Dr. Valicenti said. “Clearly, the CCR score may provide highly precise, personalized estimates and justifies testing in tiered and appropriately powered noninferiority studies according to NCCN risk groups. We eagerly await the completion and reporting of such trials so that we have a more personalized approach to treating men with prostate cancer.”

The current study was funded by Myriad Genetics, the company that developed the Prolaris test. Dr. Tward disclosed relationships with Myriad Genetics, Bayer, Blue Earth Diagnostics, Janssen Scientific Affairs, and Merck. Dr. Valicenti has no disclosures.

aotto@mdedge.com

The genomic landscape of circulating tumor DNA (ctDNA) was comparable to the landscape of tissue biopsies in a large study of patients with metastatic castration-resistant prostate cancer (mCRPC), according to researchers.

The type and frequency of genomic alterations observed were largely similar in ctDNA and tissue, and there was high concordance for BRCA1/2 alterations. Comprehensive genomic profiling (CGP) of ctDNA detected more acquired resistance alterations, which included novel androgen receptor (AR)–activating variants. In fact, alterations in nine genes were significantly enriched in ctDNA, but some of these alterations may be attributable to clonal hematopoiesis and not the tumor.

Still, the researchers concluded that CGP of ctDNA could complement tissue-based CGP.

“This is the largest study of mCRPC plasma samples conducted to date, and CGP of ctDNA recapitulated the genomic landscape detected in tissue biopsies,” said investigator Hanna Tukachinsky, PhD, from Foundation Medicine, the company that developed the liquid biopsy tests used in this study.

“The large percentage of patients with rich genomic signal from ctDNA and the sensitive, specific detection of BRCA1/2 alterations position liquid biopsy as a compelling clinical complement to tissue CGP for patients with mCRPC.”

Dr. Tukachinsky presented results from this study at the 2021 Genitourinary Cancers Symposium (Abstract 25). The results were also published in Clinical Cancer Research, but the following data are from the meeting presentation.

ctDNA profiling proves feasible, comparable

CGP was performed on 3,334 liquid biopsy samples and 2,006 tissue samples from patients with mCRPC, including patients in the TRITON2 and TRITON3 trials.

The plasma samples were profiled using FoundationACT, which had a panel of 62 genes, or FoundationOne Liquid CDx, which had a panel of 70 genes.

Most of the liquid biopsy samples – 94% – had detectable ctDNA, and the median ctDNA fraction was 7.5%.

“One of the most important findings in this study is the fact that the majority of patients with advanced prostate cancer – 94% of them – have abundant ctDNA,” Dr. Tukachinsky said.

“The overall landscape we detected in ctDNA highly resembles landscapes reported in tissue-based CGP studies of mCRPC,” she added.

ctDNA results showed a high percentage of TP53 and AR alterations, as well as alterations in DNA repair genes (ATM, CHEK2, BRCA2, and CDK12), PI3 kinase components (PTEN, PIK3CA, and AKT1), and WNT components (APC and CTNNB1).

“It should be noted that the two assays did not bait for TMPRSS2-ERT fusions or SPOP ... and we’re missing homozygous deletions, which affects the frequency we detect PTEN, RB1, and BRCA alterations,” Dr. Tukachinsky said.

When the researchers compared results from the 3,334 liquid biopsy samples and the 2,006 tissue samples, they found that most genes were altered at similar rates.

However, nine genes were significantly enriched in ctDNA – AR, TP53, ATM, CHEK2, NF1, TERT, JAK2, IDH2, and GNAS.

Dr. Tukachinsky noted that JAK2, GNAS, and IDH2 alterations are rarely detected in mCRPC tissue and are likely attributable to clonal hematopoiesis. Alterations in TERT and NF1, as well as some of the alterations in ATM and CHEK2, might also be attributed to clonal hematopoiesis, she added.

Rare and novel AR alterations

“ctDNA detected more acquired resistance genomic alterations than tissue, including novel and rare AR-activating variants,” Dr. Tukachinsky said.

She noted that F877L/T878A, a compound mutant that has been shown to confer synergistic resistance to enzalutamide, was found in 11 patients.

Similarly, “completely novel” in-frame mutations spanning residues H875 to T878 were found in 11 patients, and each shifted S885 into the T878 position.

“Although these require more experiments to prove that they are activating, their repeated appearance in different patients with mCRPC and alignment of the serine residues is highly suggestive that they are activating,” Dr. Tukachinsky said.

The researchers also found, in 160 patients, AR rearrangements that truncate the reading frame just after exon 3 to yield a receptor with an intact DNA binding domain but without a ligand binding domain.

“These truncated receptors have been demonstrated to confer resistance to AR signaling inhibitors and drive transcription of the AR target genes,” Dr. Tukachinsky said.

BRCA1/2: High concordance

To further assess concordance between ctDNA and tissue, Dr. Tukachinsky and colleagues evaluated a subset of 837 patients with matched tissue and liquid biopsies.

The researchers observed high concordance in BRCA1/2 short variants and rearrangements. The positive percent agreement was 93.1%, the negative percent agreement was 97.4%, and the overall percent agreement was 97.0%.

There were 5 patients in whom BRCA1/2 alterations were detected in tissue but not ctDNA, and there were 20 patients in whom BRCA1/2 alterations were detected in ctDNA but not tissue.

The false negatives could be the result of low ctDNA fraction, a minor clone, or filtering out by post analytics, said study discussant Silke Gillessen, MD, of the Institute of Oncology of Southern Switzerland in Bellinzona. She also postulated that the false positives could be explained by clonal hematopoiesis or metastases from a subclone.

Implications for practice

This study showed that liquid and tissue biopsies can perform comparably in identifying patients with BRCA1/2 variants who may benefit from PARP inhibition, Dr. Tukachinsky noted. Additionally, ctDNA revealed novel AR variants that may be driving resistance to AR-signaling inhibitors. However, the presence of alterations that may derive from clonal hematopoiesis suggests ctDNA results should be interpreted with some caution, she added.

“NCCN [National Comprehensive Cancer Network] guidelines have recently changed to include liquid biopsy as an option. There’s definitely some skepticism about liquid biopsy …. That said, liquid biopsy is also a pretty powerful tool,” Dr. Tukachinsky said.

“We are not advocating liquid biopsy over tissue. In the cases where tissue’s not available, or if you have a primary, in some cases, liquid could serve as a good complement to give you the full picture of what’s going on in the tumor,” she added.

“For the time being, tissue will still be our gold standard,” Dr. Gillessen said. “And if we can’t get the tissue tested, that will be then maybe a point for the liquid biopsy.”

Dr. Tukachinsky’s research was funded by Foundation Medicine and Clovis Oncology. She and her colleagues disclosed relationships with both companies and a range of other companies. Dr. Gillessen disclosed relationships with Amgen, Astellas Pharma, Bayer, and several other companies as well as a patent for a biomarker method (WO 3752009138392 A1).

The genomic landscape of circulating tumor DNA (ctDNA) was comparable to the landscape of tissue biopsies in a large study of patients with metastatic castration-resistant prostate cancer (mCRPC), according to researchers.

The type and frequency of genomic alterations observed were largely similar in ctDNA and tissue, and there was high concordance for BRCA1/2 alterations. Comprehensive genomic profiling (CGP) of ctDNA detected more acquired resistance alterations, which included novel androgen receptor (AR)–activating variants. In fact, alterations in nine genes were significantly enriched in ctDNA, but some of these alterations may be attributable to clonal hematopoiesis and not the tumor.

Still, the researchers concluded that CGP of ctDNA could complement tissue-based CGP.

“This is the largest study of mCRPC plasma samples conducted to date, and CGP of ctDNA recapitulated the genomic landscape detected in tissue biopsies,” said investigator Hanna Tukachinsky, PhD, from Foundation Medicine, the company that developed the liquid biopsy tests used in this study.

“The large percentage of patients with rich genomic signal from ctDNA and the sensitive, specific detection of BRCA1/2 alterations position liquid biopsy as a compelling clinical complement to tissue CGP for patients with mCRPC.”

Dr. Tukachinsky presented results from this study at the 2021 Genitourinary Cancers Symposium (Abstract 25). The results were also published in Clinical Cancer Research, but the following data are from the meeting presentation.

ctDNA profiling proves feasible, comparable

CGP was performed on 3,334 liquid biopsy samples and 2,006 tissue samples from patients with mCRPC, including patients in the TRITON2 and TRITON3 trials.

The plasma samples were profiled using FoundationACT, which had a panel of 62 genes, or FoundationOne Liquid CDx, which had a panel of 70 genes.

Most of the liquid biopsy samples – 94% – had detectable ctDNA, and the median ctDNA fraction was 7.5%.

“One of the most important findings in this study is the fact that the majority of patients with advanced prostate cancer – 94% of them – have abundant ctDNA,” Dr. Tukachinsky said.

“The overall landscape we detected in ctDNA highly resembles landscapes reported in tissue-based CGP studies of mCRPC,” she added.

ctDNA results showed a high percentage of TP53 and AR alterations, as well as alterations in DNA repair genes (ATM, CHEK2, BRCA2, and CDK12), PI3 kinase components (PTEN, PIK3CA, and AKT1), and WNT components (APC and CTNNB1).

“It should be noted that the two assays did not bait for TMPRSS2-ERT fusions or SPOP ... and we’re missing homozygous deletions, which affects the frequency we detect PTEN, RB1, and BRCA alterations,” Dr. Tukachinsky said.

When the researchers compared results from the 3,334 liquid biopsy samples and the 2,006 tissue samples, they found that most genes were altered at similar rates.

However, nine genes were significantly enriched in ctDNA – AR, TP53, ATM, CHEK2, NF1, TERT, JAK2, IDH2, and GNAS.

Dr. Tukachinsky noted that JAK2, GNAS, and IDH2 alterations are rarely detected in mCRPC tissue and are likely attributable to clonal hematopoiesis. Alterations in TERT and NF1, as well as some of the alterations in ATM and CHEK2, might also be attributed to clonal hematopoiesis, she added.

Rare and novel AR alterations

“ctDNA detected more acquired resistance genomic alterations than tissue, including novel and rare AR-activating variants,” Dr. Tukachinsky said.

She noted that F877L/T878A, a compound mutant that has been shown to confer synergistic resistance to enzalutamide, was found in 11 patients.

Similarly, “completely novel” in-frame mutations spanning residues H875 to T878 were found in 11 patients, and each shifted S885 into the T878 position.

“Although these require more experiments to prove that they are activating, their repeated appearance in different patients with mCRPC and alignment of the serine residues is highly suggestive that they are activating,” Dr. Tukachinsky said.

The researchers also found, in 160 patients, AR rearrangements that truncate the reading frame just after exon 3 to yield a receptor with an intact DNA binding domain but without a ligand binding domain.

“These truncated receptors have been demonstrated to confer resistance to AR signaling inhibitors and drive transcription of the AR target genes,” Dr. Tukachinsky said.

BRCA1/2: High concordance

To further assess concordance between ctDNA and tissue, Dr. Tukachinsky and colleagues evaluated a subset of 837 patients with matched tissue and liquid biopsies.

The researchers observed high concordance in BRCA1/2 short variants and rearrangements. The positive percent agreement was 93.1%, the negative percent agreement was 97.4%, and the overall percent agreement was 97.0%.

There were 5 patients in whom BRCA1/2 alterations were detected in tissue but not ctDNA, and there were 20 patients in whom BRCA1/2 alterations were detected in ctDNA but not tissue.

The false negatives could be the result of low ctDNA fraction, a minor clone, or filtering out by post analytics, said study discussant Silke Gillessen, MD, of the Institute of Oncology of Southern Switzerland in Bellinzona. She also postulated that the false positives could be explained by clonal hematopoiesis or metastases from a subclone.

Implications for practice

This study showed that liquid and tissue biopsies can perform comparably in identifying patients with BRCA1/2 variants who may benefit from PARP inhibition, Dr. Tukachinsky noted. Additionally, ctDNA revealed novel AR variants that may be driving resistance to AR-signaling inhibitors. However, the presence of alterations that may derive from clonal hematopoiesis suggests ctDNA results should be interpreted with some caution, she added.

“NCCN [National Comprehensive Cancer Network] guidelines have recently changed to include liquid biopsy as an option. There’s definitely some skepticism about liquid biopsy …. That said, liquid biopsy is also a pretty powerful tool,” Dr. Tukachinsky said.

“We are not advocating liquid biopsy over tissue. In the cases where tissue’s not available, or if you have a primary, in some cases, liquid could serve as a good complement to give you the full picture of what’s going on in the tumor,” she added.

“For the time being, tissue will still be our gold standard,” Dr. Gillessen said. “And if we can’t get the tissue tested, that will be then maybe a point for the liquid biopsy.”

Dr. Tukachinsky’s research was funded by Foundation Medicine and Clovis Oncology. She and her colleagues disclosed relationships with both companies and a range of other companies. Dr. Gillessen disclosed relationships with Amgen, Astellas Pharma, Bayer, and several other companies as well as a patent for a biomarker method (WO 3752009138392 A1).

The genomic landscape of circulating tumor DNA (ctDNA) was comparable to the landscape of tissue biopsies in a large study of patients with metastatic castration-resistant prostate cancer (mCRPC), according to researchers.

The type and frequency of genomic alterations observed were largely similar in ctDNA and tissue, and there was high concordance for BRCA1/2 alterations. Comprehensive genomic profiling (CGP) of ctDNA detected more acquired resistance alterations, which included novel androgen receptor (AR)–activating variants. In fact, alterations in nine genes were significantly enriched in ctDNA, but some of these alterations may be attributable to clonal hematopoiesis and not the tumor.

Still, the researchers concluded that CGP of ctDNA could complement tissue-based CGP.

“This is the largest study of mCRPC plasma samples conducted to date, and CGP of ctDNA recapitulated the genomic landscape detected in tissue biopsies,” said investigator Hanna Tukachinsky, PhD, from Foundation Medicine, the company that developed the liquid biopsy tests used in this study.

“The large percentage of patients with rich genomic signal from ctDNA and the sensitive, specific detection of BRCA1/2 alterations position liquid biopsy as a compelling clinical complement to tissue CGP for patients with mCRPC.”

Dr. Tukachinsky presented results from this study at the 2021 Genitourinary Cancers Symposium (Abstract 25). The results were also published in Clinical Cancer Research, but the following data are from the meeting presentation.

ctDNA profiling proves feasible, comparable

CGP was performed on 3,334 liquid biopsy samples and 2,006 tissue samples from patients with mCRPC, including patients in the TRITON2 and TRITON3 trials.

The plasma samples were profiled using FoundationACT, which had a panel of 62 genes, or FoundationOne Liquid CDx, which had a panel of 70 genes.

Most of the liquid biopsy samples – 94% – had detectable ctDNA, and the median ctDNA fraction was 7.5%.

“One of the most important findings in this study is the fact that the majority of patients with advanced prostate cancer – 94% of them – have abundant ctDNA,” Dr. Tukachinsky said.

“The overall landscape we detected in ctDNA highly resembles landscapes reported in tissue-based CGP studies of mCRPC,” she added.

ctDNA results showed a high percentage of TP53 and AR alterations, as well as alterations in DNA repair genes (ATM, CHEK2, BRCA2, and CDK12), PI3 kinase components (PTEN, PIK3CA, and AKT1), and WNT components (APC and CTNNB1).

“It should be noted that the two assays did not bait for TMPRSS2-ERT fusions or SPOP ... and we’re missing homozygous deletions, which affects the frequency we detect PTEN, RB1, and BRCA alterations,” Dr. Tukachinsky said.

When the researchers compared results from the 3,334 liquid biopsy samples and the 2,006 tissue samples, they found that most genes were altered at similar rates.

However, nine genes were significantly enriched in ctDNA – AR, TP53, ATM, CHEK2, NF1, TERT, JAK2, IDH2, and GNAS.

Dr. Tukachinsky noted that JAK2, GNAS, and IDH2 alterations are rarely detected in mCRPC tissue and are likely attributable to clonal hematopoiesis. Alterations in TERT and NF1, as well as some of the alterations in ATM and CHEK2, might also be attributed to clonal hematopoiesis, she added.

Rare and novel AR alterations

“ctDNA detected more acquired resistance genomic alterations than tissue, including novel and rare AR-activating variants,” Dr. Tukachinsky said.

She noted that F877L/T878A, a compound mutant that has been shown to confer synergistic resistance to enzalutamide, was found in 11 patients.

Similarly, “completely novel” in-frame mutations spanning residues H875 to T878 were found in 11 patients, and each shifted S885 into the T878 position.

“Although these require more experiments to prove that they are activating, their repeated appearance in different patients with mCRPC and alignment of the serine residues is highly suggestive that they are activating,” Dr. Tukachinsky said.

The researchers also found, in 160 patients, AR rearrangements that truncate the reading frame just after exon 3 to yield a receptor with an intact DNA binding domain but without a ligand binding domain.

“These truncated receptors have been demonstrated to confer resistance to AR signaling inhibitors and drive transcription of the AR target genes,” Dr. Tukachinsky said.

BRCA1/2: High concordance

To further assess concordance between ctDNA and tissue, Dr. Tukachinsky and colleagues evaluated a subset of 837 patients with matched tissue and liquid biopsies.

The researchers observed high concordance in BRCA1/2 short variants and rearrangements. The positive percent agreement was 93.1%, the negative percent agreement was 97.4%, and the overall percent agreement was 97.0%.

There were 5 patients in whom BRCA1/2 alterations were detected in tissue but not ctDNA, and there were 20 patients in whom BRCA1/2 alterations were detected in ctDNA but not tissue.

The false negatives could be the result of low ctDNA fraction, a minor clone, or filtering out by post analytics, said study discussant Silke Gillessen, MD, of the Institute of Oncology of Southern Switzerland in Bellinzona. She also postulated that the false positives could be explained by clonal hematopoiesis or metastases from a subclone.

Implications for practice

This study showed that liquid and tissue biopsies can perform comparably in identifying patients with BRCA1/2 variants who may benefit from PARP inhibition, Dr. Tukachinsky noted. Additionally, ctDNA revealed novel AR variants that may be driving resistance to AR-signaling inhibitors. However, the presence of alterations that may derive from clonal hematopoiesis suggests ctDNA results should be interpreted with some caution, she added.

“NCCN [National Comprehensive Cancer Network] guidelines have recently changed to include liquid biopsy as an option. There’s definitely some skepticism about liquid biopsy …. That said, liquid biopsy is also a pretty powerful tool,” Dr. Tukachinsky said.

“We are not advocating liquid biopsy over tissue. In the cases where tissue’s not available, or if you have a primary, in some cases, liquid could serve as a good complement to give you the full picture of what’s going on in the tumor,” she added.

“For the time being, tissue will still be our gold standard,” Dr. Gillessen said. “And if we can’t get the tissue tested, that will be then maybe a point for the liquid biopsy.”

Dr. Tukachinsky’s research was funded by Foundation Medicine and Clovis Oncology. She and her colleagues disclosed relationships with both companies and a range of other companies. Dr. Gillessen disclosed relationships with Amgen, Astellas Pharma, Bayer, and several other companies as well as a patent for a biomarker method (WO 3752009138392 A1).