ASCO Breast Cancer

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

In patients with newly diagnosed stage IV breast cancer and an intact primary tumor, locoregional therapy after optimal systemic therapy does not improve survival or quality of life, results of the phase 3 E2108 trial suggest.

Among 256 patients with stage IV breast cancer with intact primary tumors who had no disease progression for 4-8 months after the start of optimal systemic therapy, there were no significant differences in overall survival or progression-free survival between patients randomized to receive locoregional therapy and those who did not receive the locoregional treatment.

Although patients who did not receive locoregional treatment had a 150% higher rate of local recurrence/progression, health-related quality of life (HRQOL) was actually worse at 18 months among the patients who underwent locoregional therapy. There were no HRQOL differences at 6 months, 12 months, or 30 months of follow-up.

Seema A. Khan, MD, of Northwestern University, Chicago, reported these results during a plenary session broadcast as a part of the American Society of Clinical Oncology virtual scientific program.

“There is no hint here of an advantage in terms of survival with the use of early locoregional therapy for the primary site,” Dr. Khan said.

Although neither the E2108 trial nor similar trials showed an overall survival advantage for locoregional therapy, as many as 20% of patients who are treated with systemic therapy alone may need locoregional therapy with surgery and/or radiation at some point for palliation or progression, said invited discussant Julia R. White, MD, professor of radiation oncology at the Ohio State University, Columbus.

“Locoregional therapy should be reserved for these patients that become symptomatic or progress locally. There may be a role for routine locoregional therapy for de novo oligometastatic breast cancer in combination with systemic therapy plus ablative therapy” to secure long-term remission or cure, questions that are being addressed in ongoing clinical trials, Dr. White said.
 

Past data

An estimated 6% of newly diagnosed breast cancer patients present with stage IV disease and an intact primary tumor.

The rationale for locoregional therapy of the primary tumor in patients with metastatic disease is based on retrospective data suggesting a survival advantage. However, the studies were biased because of younger patient populations with small tumors, a higher proportion of estrogen receptor–positive disease, and a generally lower metastatic burden than that seen in the E2108 population, according to Dr. Khan.

She went on to cite two randomized trials with differing outcomes. One trial showed no survival advantage with locoregional therapy at 2 years (Lancet Oncol. 2015 Oct;16[13]:1380-8). The other showed an improvement in survival with locoregional therapy at 5 years (Ann Surg Oncol. 2018 Oct;25[11]:3141-9).
 

E2108 details

In the E2108 trial, patients first received optimal systemic therapy based on individual patient and disease features. Patients who had no disease progression or distant disease for at least 4-8 months of therapy were then randomized to additional therapy.

In one randomized arm, patients received continued systemic therapy alone. The other arm received early local therapy, which included complete tumor resection with free surgical margins and postoperative radiotherapy according to the standard of care.

A total of 390 patients were registered, and 256 went on to randomization. Of those subjects, 131 were randomized to the continued systemic therapy arm and 125 to the early local therapy arm. All patients in each arm were included in the efficacy analysis.

In all, 59.6% of randomized patients had hormone receptor–positive/HER2-negative disease, 8.2% had triple-negative disease, and 32.2% had HER2-positive disease. Metastases included bone-only disease in 37.9% of patients, visceral-only disease in 24.2%, and 40.9% in both sites.

Among the patients randomized to early local therapy, 14 did not have surgery for personal, clinical, or insurance reasons. Of the 109 who went on to surgery, 87 had clear surgical margins, and 74 received locoregional radiation therapy.
 

Survival, progression, and HRQOL

At a median follow-up of 53 months, the median overall survival was 54 months in each arm. There was no significant difference in survival between the study arms, with superimposable survival curves (hazard ratio, 1.09; P = .63).

An analysis of overall survival by tumor type showed that, for the 20 women with triple-negative disease, survival was worse with early local therapy (HR, 3.50). There were no differences in survival either for the 79 patients with HER2-positive disease or for the 137 patients with hormone receptor–positive/HER2-negative disease.

Locoregional progression occurred in 25.6% of patients assigned to continued systemic therapy, compared with 10.2% assigned to early local therapy. However, progression-free survival was virtually identical between the study arms (P = .40).

At most time points, there were no significant between-arm differences in HRQOL. The exception was at 18 months of follow-up, when the HRQOL was significantly lower among patients who had undergone early local therapy (P = .001).

“Based on available data, locoregional therapy for the primary tumor should not be offered to women with stage IV breast cancer with the expectation of a survival benefit. When systemic disease is well controlled with systemic therapy but the primary site is progressing, as does happen occasionally, locoregional treatment can be considered,” Dr. Khan concluded.

She noted there is an ongoing trial of similar design in Japan (JCOG-1017), with results expected in 2022.

The current trial was supported by the National Cancer Institute and Canadian Cancer Society. Dr. Khan reported no conflicts of interest. Dr. White reported institutional research funding from Intraop Medical.

SOURCE: Khan SA et al. ASCO 2020, Abstract LBA2.

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

The combination of pyrotinib and capecitabine significantly prolonged progression-free survival (PFS), when compared with lapatinib and capecitabine, among patients with previously treated HER2-positive metastatic breast cancer in a phase 3 trial.

PFS was extended by nearly 6 months among patients who received pyrotinib, a novel pan-HER2 inhibitor, combined with capecitabine. Grade 3 diarrhea occurred in nearly 31% of patients receiving the pyrotinib-capecitabine combination, though none of the patients discontinued treatment due to this adverse event.

Binghe Xu, MD, PhD, of the National Cancer Center/Cancer Hospital at the Chinese Academy of Medical Sciences and Peking Union Medical College in Beijing, presented these results, from the phase 3 PHOEBE trial, as part of the American Society of Clinical Oncology virtual scientific program.
 

The value of pyrotinib

Although there are already many targeted therapies for HER2-positive metastatic breast cancer, accessibility can be an issue, with drugs such as pertuzumab and trastuzumab emtansine (T-DM1) not available in all regions of the world, according to Dr. Xu.

“Before we initiated this clinical trial, lapatinib plus capecitabine was the only second-line standard of care against HER2-positive metastatic breast cancer in China,” he said.

Based, in part, on results of the PHOEBE trial, the combination of pyrotinib and capecitabine was approved in China as a second-line standard of care for patients with HER2-positive metastatic breast cancer, according to Dr. Xu.

Pyrotinib has now demonstrated “clinical value” in two phase 3 clinical trials, but its value in relation to pertuzumab, T-DM1, tucatinib, trastuzumab deruxtecan, or neratinib is less clear, said Aleix Prat, MD, PhD, of Hospital Clinic of Barcelona.

“Also, in my opinion, the toxicity profile needs attention,” Dr. Prat said in a discussion of the PHOEBE results that was also part of the virtual ASCO meeting.

The 31% incidence of grade 3 diarrhea was “very similar,” he said, to what was seen in PHENIX, another phase 3 trial of pyrotinib plus capecitabine that was presented at the 2019 ASCO annual meeting (J Clin Oncol 37, 2019 suppl; abstr 1001).

“What is the current therapy landscape? In my opinion, today, the first line remains taxane, trastuzumab, and pertuzumab; the second line T-DM1; and the third line tucatinib, trastuzumab, and capecitabine, with other treatment strategies reserved for later lines,” Dr. Prat said.

Study details

PHOEBE included 267 patients with HER2-positive metastatic breast cancer. They had previously received trastuzumab and taxanes, and/or anthracyclines, with up to two prior lines of chemotherapy for metastatic disease.

The patients’ median age was 50 years, 79% had visceral metastases at screening, and about 26% had trastuzumab resistance, Dr. Xu said. Resistance was defined as relapse within 6 months after adjuvant treatment or progression within 3 months of treatment for metastatic disease.

A statistically significant and clinically meaningful improvement was seen in PFS, the primary endpoint of the study, Dr. Xu said.

Median PFS by blinded independent central review was 12.5 months for the pyrotinib-capecitabine combination, compared with 6.8 months for lapatinib-capecitabine (hazard ratio, 0.39; 95% confidence interval, 0.27-0.56; P < .0001).

The PFS benefit was consistently observed across all predefined subgroups, including by trastuzumab resistance.

In trastuzumab-resistant patients, the median PFS was 12.5 months for the pyrotinib combination and 6.9 months for the lapatinib combination (HR, 0.60; 95% CI, 0.29-1.21). In patients without trastuzumab resistance, the median PFS was 12.5 months and 5.6 months, respectively (HR, 0.33; 95% CI, 0.21-0.51).

Although overall survival (OS) data were not yet mature, there was a “strong trend” toward a benefit with pyrotinib, Dr. Xu said. The 12-month OS rate was 91.3% for the pyrotinib combination and 77.4% for lapatinib. The median OS was not reached in either arm at the time of analysis.

Treatment-related adverse events of grade 3 or greater occurred in 57.5% of the pyrotinib arm and 34.1% of the lapatinib arm.

Diarrhea was the most common grade 3 or greater treatment-related adverse event, occurring in 30.6% of patients in the pyrotinib arm and 8.3% of those in the lapatinib arm. No grade 4 or 5 diarrhea was seen.

Overall, diarrhea occurred in 94.8% of patients in the pyrotinib arm and 62.1% of those in the lapatinib arm. However, pyrotinib-associated diarrhea was generally of low severity, occurred early, had a short duration, was reversible, and did not lead to treatment termination, according to Dr. Xu.

This study was funded by Jiangsu Hengrui Medicine Co. Ltd. Dr. Xu reported additional disclosures related to AstraZeneca, Eisai, Pfizer, and Roche. Dr. Prat disclosed relationships with Amgen, Daiichi Sankyo, Lilly, MSD Oncology, and other companies.

SOURCE: Xu B et al. ASCO 2020, Abstract 1003

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

For patients with BRCA-like triple-negative breast cancer (TNBC), adding veliparib to cisplatin chemotherapy may extend survival, based on results from the phase 3 SWOG S1416 trial.

All patients with BRCA-like TNBC had a significant improvement in progression-free survival (PFS) when they received veliparib plus cisplatin. Previously untreated patients with BRCA-like TNBC had a significant improvement in overall survival (OS) as well.

The results are a “very positive step towards expanding the role of PARP inhibitors beyond germline BRCA in breast cancer,” reported lead author Priyanka Sharma, MD, of the University of Kansas Medical Center in Kansas City, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

According to Dr. Sharma, PARP inhibitors have demonstrated efficacy for certain patients with BRCA wild-type ovarian cancer, such as those with homologous recombination deficiency, which also occurs in approximately half of patients with BRCA wild-type TNBC. In TNBC, homologous recombination deficiency and other aberrations lead to a BRCA-like disease phenotype, which may respond to PARP inhibitors.

Dr. Sharma noted that previous attempts to use PARP inhibitors for BRCA wild-type TNBC have revealed obstacles, such as the inefficacy of PARP inhibitor monotherapy and dose-limiting myelosuppression when PARP inhibitors were added to chemotherapy. The issue of bone marrow toxicity may be mitigated by veliparib, which has minimal PARP-trapping activity, she explained.

“A phase 1 trial has demonstrated that adequate doses of cisplatin can be delivered safely in combination with the near-maximal single-agent dose of veliparib in patients with metastatic TNBC,” Dr. Sharma said.

She and her colleagues put this finding to the test in a phase 3 trial that enrolled 335 patients with metastatic and/or loco-regionally recurrent TNBC or BRCA-associated HER2-negative breast cancer. Patients could be previously untreated or have received one prior cytotoxic chemotherapy for metastatic disease.

Of the patients enrolled, 321 met eligibility criteria, 294 had germline BRCA testing, and 209 had BRCA-like assessment.

Patients were divided into the following groups: germline BRCA-associated disease (n = 37), BRCA-like disease (n = 99), non-BRCA-like disease (n = 110), and unclassified (n = 75).

In each group, patients were randomized in a 1:1 ratio to receive cisplatin (75 mg/m²on day 1) plus veliparib (300 mg twice daily on days 1-14) every 3 weeks, or cisplatin with placebo. The primary endpoint was PFS.

Results

Among patients with BRCA-like disease, there was a significant improvement in PFS and a trend toward improved OS when veliparib was added to cisplatin. The median PFS was 5.9 months with veliparib and 4.2 months with placebo (P = .006). The median OS was 14.0 months and 12.1 months, respectively (P = .067).

Among patients with previously untreated BRCA-like disease, there were significant improvements in both PFS and OS.

The median PFS in this group was 6.1 months with veliparib and 4.2 months with placebo (P = .008). The 12-month PFS rates were 23% and 3%, respectively.

The median OS in this group was 17.8 months with veliparib and 10.3 months with placebo (P = .048). The 24-month OS rates were 43% and 20%, respectively.

There were no survival benefits with veliparib among patients with unclassified disease, non-BRCA-like disease, or BRCA-associated disease.

Dr. Sharma noted that the lack of significant improvement in the BRCA-associated group was likely due to the small sample size. “FDA approval of PARP inhibitors for treatment of germline BRCA-associated metastatic breast cancer during the course of this trial impacted accrual to this group,” she said.

Veliparib was associated with a higher rate of grade 3-4 hematologic toxicities, including neutropenia (46% vs. 19%), leukopenia (27% vs. 7%), anemia (23% vs. 7%), and thrombocytopenia (19% vs. 3%).

Dr. Sharma said results from this trial should prompt further research. “The combination of veliparib plus cisplatin warrants further evaluation in larger randomized trials for patients with BRCA-like phenotype TNBC,” she said.

Invited discussant Catherine M. Kelly, MB BCh, of Mater Misericordiae University Hospital in Dublin, called the trial “an ambitious study” that has created a “valuable tissue bank” for future translational research. She agreed that more work is necessary.

“Further research is needed to identify the optimal homologous recombination deficiency biomarkers critical in the early treatment-naive and in the advanced treatment-exposed disease settings,” Dr. Kelly said.

SWOG S1416 was funded by the National Institutes of Health and AbbVie. Dr. Sharma disclosed relationships with AstraZeneca, Merck, Novartis, and other companies. Dr. Kelly reported affiliations with Pfizer, Novartis, Roche, and MSD Oncology.

SOURCE: Sharma et al. ASCO 2020, Abstract 1001.

Neither fulvestrant alone nor fulvestrant plus anastrozole improved the endocrine-sensitive disease rate (ESDR) versus anastrozole alone as neoadjuvant endocrine therapy in postmenopausal women with locally advanced estrogen receptor-positive HER2-negative (ER+ HER2–) breast cancer in the phase 3 ALTERNATE trial.

The ESDRs were 22.7% in 431 evaluable patients randomized to receive fulvestrant alone, 20.5% in 434 patients who received fulvestrant + anastrozole, and 18.6% in 434 who received anastrozole alone, Cynthia X. Ma, MD, PhD, reported as part of the American Society of Clinical Oncology virtual scientific program.

The differences between the anastrozole-only and the fulvestrant groups did not differ significantly, said Dr. Ma, a professor at Washington University in St. Louis.

Study subjects had a median age of 64 years, clinical stage II/III ER+ HER2– breast cancer, and were randomized 1:1:1 between February 2014 and November 2018 to receive 6 months of treatment with 500 mg of intramuscular fulvestrant given every 4 weeks following a loading dose, fulvestrant plus a 1 mg daily oral does of anastrozole, or anastrozole alone prior to breast conserving surgery.

The groups were similar with respect to baseline characteristics, and more than 70% were eligible for breast conserving surgery prior to the start of neoadjuvant therapy, Dr. Ma noted, adding that the treatments were well tolerated.

Grade 3 or 4 adverse events were rare, and the percentage of patients experiencing arthralgia, myalgia, or hot flashes was low and similar across arms, she said.

“Neoadjuvant therapy downstages the tumor and improves the rate of breast conserving surgery,” Dr. Ma said, adding that pathologic tumor size, nodal status, Ki67 level, and ER status of resected tumors after neoadjuvant therapy have been shown to be independent prognostic factors for relapse-free survival.

sworcester@mdedge.com

SOURCE: Ma C et al. ASCO 2020: Abstract 504.

Neither fulvestrant alone nor fulvestrant plus anastrozole improved the endocrine-sensitive disease rate (ESDR) versus anastrozole alone as neoadjuvant endocrine therapy in postmenopausal women with locally advanced estrogen receptor-positive HER2-negative (ER+ HER2–) breast cancer in the phase 3 ALTERNATE trial.

The ESDRs were 22.7% in 431 evaluable patients randomized to receive fulvestrant alone, 20.5% in 434 patients who received fulvestrant + anastrozole, and 18.6% in 434 who received anastrozole alone, Cynthia X. Ma, MD, PhD, reported as part of the American Society of Clinical Oncology virtual scientific program.

The differences between the anastrozole-only and the fulvestrant groups did not differ significantly, said Dr. Ma, a professor at Washington University in St. Louis.

Study subjects had a median age of 64 years, clinical stage II/III ER+ HER2– breast cancer, and were randomized 1:1:1 between February 2014 and November 2018 to receive 6 months of treatment with 500 mg of intramuscular fulvestrant given every 4 weeks following a loading dose, fulvestrant plus a 1 mg daily oral does of anastrozole, or anastrozole alone prior to breast conserving surgery.

The groups were similar with respect to baseline characteristics, and more than 70% were eligible for breast conserving surgery prior to the start of neoadjuvant therapy, Dr. Ma noted, adding that the treatments were well tolerated.

Grade 3 or 4 adverse events were rare, and the percentage of patients experiencing arthralgia, myalgia, or hot flashes was low and similar across arms, she said.

“Neoadjuvant therapy downstages the tumor and improves the rate of breast conserving surgery,” Dr. Ma said, adding that pathologic tumor size, nodal status, Ki67 level, and ER status of resected tumors after neoadjuvant therapy have been shown to be independent prognostic factors for relapse-free survival.

sworcester@mdedge.com

SOURCE: Ma C et al. ASCO 2020: Abstract 504.

Neither fulvestrant alone nor fulvestrant plus anastrozole improved the endocrine-sensitive disease rate (ESDR) versus anastrozole alone as neoadjuvant endocrine therapy in postmenopausal women with locally advanced estrogen receptor-positive HER2-negative (ER+ HER2–) breast cancer in the phase 3 ALTERNATE trial.

The ESDRs were 22.7% in 431 evaluable patients randomized to receive fulvestrant alone, 20.5% in 434 patients who received fulvestrant + anastrozole, and 18.6% in 434 who received anastrozole alone, Cynthia X. Ma, MD, PhD, reported as part of the American Society of Clinical Oncology virtual scientific program.

The differences between the anastrozole-only and the fulvestrant groups did not differ significantly, said Dr. Ma, a professor at Washington University in St. Louis.

Study subjects had a median age of 64 years, clinical stage II/III ER+ HER2– breast cancer, and were randomized 1:1:1 between February 2014 and November 2018 to receive 6 months of treatment with 500 mg of intramuscular fulvestrant given every 4 weeks following a loading dose, fulvestrant plus a 1 mg daily oral does of anastrozole, or anastrozole alone prior to breast conserving surgery.

The groups were similar with respect to baseline characteristics, and more than 70% were eligible for breast conserving surgery prior to the start of neoadjuvant therapy, Dr. Ma noted, adding that the treatments were well tolerated.

Grade 3 or 4 adverse events were rare, and the percentage of patients experiencing arthralgia, myalgia, or hot flashes was low and similar across arms, she said.

“Neoadjuvant therapy downstages the tumor and improves the rate of breast conserving surgery,” Dr. Ma said, adding that pathologic tumor size, nodal status, Ki67 level, and ER status of resected tumors after neoadjuvant therapy have been shown to be independent prognostic factors for relapse-free survival.

sworcester@mdedge.com

SOURCE: Ma C et al. ASCO 2020: Abstract 504.

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

aotto@mdedge.com

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

aotto@mdedge.com

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

In HER2-positive breast cancer patients with brain metastases treated with trastuzumab and capecitabine, add-on tucatinib increased median overall survival from 12 months to 18.1 months in a phase 2 trial.

The results were presented as part of the American Society of Clinical Oncology virtual scientific program and published simultaneously in the Journal of Clinical Oncology.

At 1 year, 70% of the 198 patients who had been randomized to tucatinib were alive versus 47% of the 93 patients randomized to placebo. Tucatinib reduced the risk of death by 42% (P = .005).

“This is the first double-blind, randomized trial of systemic therapy to our knowledge [that demonstrated] clinically meaningful gains in [overall survival] among patients with [brain metastases], including those with active metastases,” Nancy Lin, MD, associate chief of the division of breast oncology at Dana-Farber Cancer Institute in Boston and colleagues wrote in the Journal of Clinical Oncology.

The findings come from a substudy of the HER2CLIMB trial, which had similar outcomes but didn’t separate women with brain metastases from others. The study won tucatinib’s maker, Seattle Genetics, Food and Drug Administration approval for tucatinib in combination with trastuzumab and capecitabine for patients with unresectable or metastatic HER2-postive disease after failure of at least one treatment for advanced disease. In the United States, tucatinib costs over $18,000 a month, according to GoodRX and other sources.



The newly approved indication for tucatinib includes patients with brain metastases, but Dr. Lin and colleagues drove the point home by analyzing HER2CLIMB data solely in the 291 subjects who had baseline CNS lesions, which occur in up to half of women with advanced HER2-positive breast cancer.

Amy Tiersten, MD, a professor at Mount Sinai Hospital in New York, was not involved in the study but is convinced of the clinical benefit of tucatinib. Tucatinib “will be the standard of care for all patients with brain metastases ... regardless of” previous treatments, she said.

“It’s a total game changer. The addition of tucatinib made a large difference, including a hefty impact on overall survival. It will be interesting to see if this drug will be useful in earlier stages to help prevent brain metastases,” Dr. Tiersten said.

Among the large benefits she alluded to, the median CNS progression-free survival (PFS) – free of lesion progression or death – was 9.9 months with tucatinib versus 4.2 months with placebo (P < .00001).

At 1 year, 40% of tucatinib patients, but no patients in the placebo arm, were alive and free of CNS progression. Tucatinib reduced the risk of intracranial progression or death by 68%.

 

Active vs. stable brain metastasis

Among the 117 patients who entered the trial with stable, treated brain metastases – most by radiation, the rest by surgery – the median CNS PFS was 13.9 months with tucatinib versus 5.6 months with placebo (P = .002). In this group, the median overall survival was 15.7 months in the tucatinib arm and 13.6 month in the placebo arm (P = .70).

“Overall survival [in stable patients] numerically favored tucatinib to a small extent, but this did not reach statistical significance, albeit in a relatively small number of patients,” Dr. Lin said in her presentation.

Between-arm differences were significant in the 174 patients who entered the trial with active brain metastases, which refers to those that were either known but untreated, newly discovered on baseline MRI, or progressed after treatment. At 1 year, 35% of these patients in the tucatinib arm were still alive and free of CNS progression; however, there were no such patients in the placebo arm.

The median CNS PFS among patients with active brain metastases at study entrance was 9.5 months with tucatinib versus 4.1 months in the placebo arm (P < .0001). The median overall survival was 20.7 months and 11.6 months, respectively (P = .004).

Intracranial response was confirmed by MRI in 47% of tucatinib-treated patients with active brain metastasis at baseline versus 20% of patients on placebo (P = .03).
 

Re-treatment after progression

Thirty subjects – 21 on tucatinib and 9 on placebo – returned to their study arm after radiation for brain lesion progression.

The risk of second progression or death was reduced 67% when patients restarted tucatinib instead of placebo.

The median time from first CNS progression to a second progression or death was 7.6 months with tucatinib versus 3.1 months with placebo (P = .02).

“The data suggest a potential benefit for continuation of tucatinib beyond first isolated CNS progression,” Dr. Lin said.

As for why tucatinib helps, she and her colleagues speculated that, because tyrosine kinase inhibitors are small molecules, they can cross the blood brain barrier and effectively treat CNS lesions, while larger, antibody-based anti-HER2 agents, such as trastuzumab and pertuzumab, cannot.

Study entry required prior treatment with trastuzumab, pertuzumab, and ado-trastuzumab emtansine, as well as an Eastern Cooperative Oncology Group performance score of 0 or 1. More than 99% of the subjects in the analysis were women, and the median age was 52 years.

The treatment groups were well balanced. A bit over half of the subjects in both arms were in North America, and 57% were estrogen and/or progesterone receptor positive. Adverse events were reported previously.

This research was funded by tucatinib’s maker, Seattle Genetics. Dr. Lin and colleagues disclosed financial relationships with Seattle Genetics, including employment. Dr. Tiersten reported no relevant conflicts of interest.

aotto@mdedge.com

SOURCE: Lin NU et al. ASCO 2020, Abstract 1005; J Clin Oncol. 2020 May 29. doi: 10.1200/JCO.20.00775

Anthracyclines add toxicity with no evidence of improved survival in patients with HER2-positive breast cancer receiving a neoadjuvant chemotherapy regimen plus dual HER2 blockade, results of a  phase 3 trial have suggested.

Event-free survival (EFS) estimates at 3 years were 93% for patients receiving anthracycline-containing chemotherapy plus trastuzumab/pertuzumab and 94% for those receiving an anthracycline-free regimen, according to long-term follow-up results of TRAIN-2, a randomized, phase 3 trial.

There was also “no evidence” that higher-risk patients would benefit from anthracyclines, said investigator Anna Van der Voort of the Netherlands Cancer Institute in Amsterdam.

“Today, anthracyclines are often used, especially in patients with higher risk of recurrence,” said Ms. Van der Voort in her presentation, which was part of the American Society of Clinical Oncology (ASCO) virtual scientific program.

“Importantly, anthracyclines increased the risk of febrile neutropenia, cardiac toxicity, and chemotherapy-associated leukemia, and therefore, a neoadjuvant anthracycline-free regimen with dual HER2 blockade should be considered in all stage II and III HER2-positive breast cancer patients,” she suggested.

With these new results, there are now “great safety data and very promising efficacy data” from two comparative studies favoring nonanthracycline regimens plus HER2 blockade over an anthracycline approach, even in patients with disease thought to be at high risk of recurrence, said Sara A. Hurvitz, MD, associate professor of medicine at the University of California Los Angeles Jonsson Comprehensive Cancer Center.

The other comparative study, BCIRG-006, demonstrated that docetaxel and carboplatin plus trastuzumab (TCH) had similar efficacy, fewer acute toxicities, and less cardiotoxicity and leukemia than did doxorubicin/cyclophosphamide followed by docetaxel (AC-T).

In a follow-up analysis focused on patients with four or more positive lymph nodes, disease-free survival was similar for the nonanthracycline and anthracycline regimens, Dr. Hurvitz noted.

“I would challenge us to think carefully about the standard use of anthracyclines when we have so many targeted therapies available for our patients with HER2-positive disease now,” Dr. Hurvitz said in her commentary on TRAIN-2 that was also part of the virtual ASCO proceedings.

The TRAIN-2 trial included 438 patients in the Netherlands with previously untreated stage II to III HER2-positive breast cancer. Patients randomized to the anthracycline-containing arm received 5-fluorouracil, epirubicin, and cyclophosphamide in three 3-week cycles followed by paclitaxel and carboplatin in six 3-week cycles.

Patients in the anthracycline-free arm received paclitaxel and carboplatin for nine 3-week cycles. Both groups also received trastuzumab and pertuzumab concurrent with chemotherapy.

The pathological complete response (pCR) rate was high with and without anthracyclines, Ms. Van der Voort said, referring to primary results of TRAIN-2 previously published in Lancet Oncology.

In that report, pCR was seen in 67% of patients in the anthracycline group, and 68% in the nonanthracycline group (P = .95), a finding that was consistent regardless of tumor size, nodal status, or hormone receptor status, said Ms. Van der Voort. She added that significantly more febrile neutropenia and hypokalemia were seen in the anthracycline group.

At virtual ASCO, Ms. Van der Voort presented results of the EFS analysis. At the time of analysis, there were 21 events among 219 patients in the nonanthracycline group (10%) and 23 events among 219 patients in the anthracycline group (11%). The corresponding 3-year EFS estimates were 93.5% and 92.7%, with a hazard ratio that favored the nonanthracycline group, though the difference between arms was not statistically significant (hazard ratio, 0.90; 95% confidence interval, 0.50-1.63).

“The results were independent of hormone receptor status, age, tumor size, nodal status, and grade, so we found no evidence that high-risk patients require anthracyclines,” said Ms. Van der Voort. Of note, results divided by nodal status suggested similar or better outcomes in the absence of anthracyclines, even in the highest-risk group, she added.

Estimated 3-year overall survival rates were likewise similar between groups, at 98.2% and 97.7% in the nonanthracycline and anthracycline arms, respectively.

Declines in left ventricular ejection fraction were more frequent in the anthracycline group (36% vs. 22% for the nonanthracycline group; P = .0016), and about one-third of patients did not recover that decline. New malignancies were found in 5% of the anthracycline group and 2% of the nonanthracycline group.

The TRAIN-2 study was sponsored by the Netherlands Cancer Institute and Roche. Ms. Van der Voort said she had no relationships to disclose. Dr. Hurwitz reported institutional research funding from multiple pharmaceutical companies including Genentech/Roche.

SOURCE: Van der Voort A et al. ASCO 2020, Abstract 501.

Anthracyclines add toxicity with no evidence of improved survival in patients with HER2-positive breast cancer receiving a neoadjuvant chemotherapy regimen plus dual HER2 blockade, results of a  phase 3 trial have suggested.

Event-free survival (EFS) estimates at 3 years were 93% for patients receiving anthracycline-containing chemotherapy plus trastuzumab/pertuzumab and 94% for those receiving an anthracycline-free regimen, according to long-term follow-up results of TRAIN-2, a randomized, phase 3 trial.

There was also “no evidence” that higher-risk patients would benefit from anthracyclines, said investigator Anna Van der Voort of the Netherlands Cancer Institute in Amsterdam.

“Today, anthracyclines are often used, especially in patients with higher risk of recurrence,” said Ms. Van der Voort in her presentation, which was part of the American Society of Clinical Oncology (ASCO) virtual scientific program.

“Importantly, anthracyclines increased the risk of febrile neutropenia, cardiac toxicity, and chemotherapy-associated leukemia, and therefore, a neoadjuvant anthracycline-free regimen with dual HER2 blockade should be considered in all stage II and III HER2-positive breast cancer patients,” she suggested.

With these new results, there are now “great safety data and very promising efficacy data” from two comparative studies favoring nonanthracycline regimens plus HER2 blockade over an anthracycline approach, even in patients with disease thought to be at high risk of recurrence, said Sara A. Hurvitz, MD, associate professor of medicine at the University of California Los Angeles Jonsson Comprehensive Cancer Center.

The other comparative study, BCIRG-006, demonstrated that docetaxel and carboplatin plus trastuzumab (TCH) had similar efficacy, fewer acute toxicities, and less cardiotoxicity and leukemia than did doxorubicin/cyclophosphamide followed by docetaxel (AC-T).

In a follow-up analysis focused on patients with four or more positive lymph nodes, disease-free survival was similar for the nonanthracycline and anthracycline regimens, Dr. Hurvitz noted.

“I would challenge us to think carefully about the standard use of anthracyclines when we have so many targeted therapies available for our patients with HER2-positive disease now,” Dr. Hurvitz said in her commentary on TRAIN-2 that was also part of the virtual ASCO proceedings.

The TRAIN-2 trial included 438 patients in the Netherlands with previously untreated stage II to III HER2-positive breast cancer. Patients randomized to the anthracycline-containing arm received 5-fluorouracil, epirubicin, and cyclophosphamide in three 3-week cycles followed by paclitaxel and carboplatin in six 3-week cycles.

Patients in the anthracycline-free arm received paclitaxel and carboplatin for nine 3-week cycles. Both groups also received trastuzumab and pertuzumab concurrent with chemotherapy.

The pathological complete response (pCR) rate was high with and without anthracyclines, Ms. Van der Voort said, referring to primary results of TRAIN-2 previously published in Lancet Oncology.

In that report, pCR was seen in 67% of patients in the anthracycline group, and 68% in the nonanthracycline group (P = .95), a finding that was consistent regardless of tumor size, nodal status, or hormone receptor status, said Ms. Van der Voort. She added that significantly more febrile neutropenia and hypokalemia were seen in the anthracycline group.

At virtual ASCO, Ms. Van der Voort presented results of the EFS analysis. At the time of analysis, there were 21 events among 219 patients in the nonanthracycline group (10%) and 23 events among 219 patients in the anthracycline group (11%). The corresponding 3-year EFS estimates were 93.5% and 92.7%, with a hazard ratio that favored the nonanthracycline group, though the difference between arms was not statistically significant (hazard ratio, 0.90; 95% confidence interval, 0.50-1.63).

“The results were independent of hormone receptor status, age, tumor size, nodal status, and grade, so we found no evidence that high-risk patients require anthracyclines,” said Ms. Van der Voort. Of note, results divided by nodal status suggested similar or better outcomes in the absence of anthracyclines, even in the highest-risk group, she added.

Estimated 3-year overall survival rates were likewise similar between groups, at 98.2% and 97.7% in the nonanthracycline and anthracycline arms, respectively.

Declines in left ventricular ejection fraction were more frequent in the anthracycline group (36% vs. 22% for the nonanthracycline group; P = .0016), and about one-third of patients did not recover that decline. New malignancies were found in 5% of the anthracycline group and 2% of the nonanthracycline group.

The TRAIN-2 study was sponsored by the Netherlands Cancer Institute and Roche. Ms. Van der Voort said she had no relationships to disclose. Dr. Hurwitz reported institutional research funding from multiple pharmaceutical companies including Genentech/Roche.

SOURCE: Van der Voort A et al. ASCO 2020, Abstract 501.

Anthracyclines add toxicity with no evidence of improved survival in patients with HER2-positive breast cancer receiving a neoadjuvant chemotherapy regimen plus dual HER2 blockade, results of a  phase 3 trial have suggested.

Event-free survival (EFS) estimates at 3 years were 93% for patients receiving anthracycline-containing chemotherapy plus trastuzumab/pertuzumab and 94% for those receiving an anthracycline-free regimen, according to long-term follow-up results of TRAIN-2, a randomized, phase 3 trial.

There was also “no evidence” that higher-risk patients would benefit from anthracyclines, said investigator Anna Van der Voort of the Netherlands Cancer Institute in Amsterdam.

“Today, anthracyclines are often used, especially in patients with higher risk of recurrence,” said Ms. Van der Voort in her presentation, which was part of the American Society of Clinical Oncology (ASCO) virtual scientific program.

“Importantly, anthracyclines increased the risk of febrile neutropenia, cardiac toxicity, and chemotherapy-associated leukemia, and therefore, a neoadjuvant anthracycline-free regimen with dual HER2 blockade should be considered in all stage II and III HER2-positive breast cancer patients,” she suggested.

With these new results, there are now “great safety data and very promising efficacy data” from two comparative studies favoring nonanthracycline regimens plus HER2 blockade over an anthracycline approach, even in patients with disease thought to be at high risk of recurrence, said Sara A. Hurvitz, MD, associate professor of medicine at the University of California Los Angeles Jonsson Comprehensive Cancer Center.

The other comparative study, BCIRG-006, demonstrated that docetaxel and carboplatin plus trastuzumab (TCH) had similar efficacy, fewer acute toxicities, and less cardiotoxicity and leukemia than did doxorubicin/cyclophosphamide followed by docetaxel (AC-T).

In a follow-up analysis focused on patients with four or more positive lymph nodes, disease-free survival was similar for the nonanthracycline and anthracycline regimens, Dr. Hurvitz noted.

“I would challenge us to think carefully about the standard use of anthracyclines when we have so many targeted therapies available for our patients with HER2-positive disease now,” Dr. Hurvitz said in her commentary on TRAIN-2 that was also part of the virtual ASCO proceedings.

The TRAIN-2 trial included 438 patients in the Netherlands with previously untreated stage II to III HER2-positive breast cancer. Patients randomized to the anthracycline-containing arm received 5-fluorouracil, epirubicin, and cyclophosphamide in three 3-week cycles followed by paclitaxel and carboplatin in six 3-week cycles.

Patients in the anthracycline-free arm received paclitaxel and carboplatin for nine 3-week cycles. Both groups also received trastuzumab and pertuzumab concurrent with chemotherapy.

The pathological complete response (pCR) rate was high with and without anthracyclines, Ms. Van der Voort said, referring to primary results of TRAIN-2 previously published in Lancet Oncology.

In that report, pCR was seen in 67% of patients in the anthracycline group, and 68% in the nonanthracycline group (P = .95), a finding that was consistent regardless of tumor size, nodal status, or hormone receptor status, said Ms. Van der Voort. She added that significantly more febrile neutropenia and hypokalemia were seen in the anthracycline group.

At virtual ASCO, Ms. Van der Voort presented results of the EFS analysis. At the time of analysis, there were 21 events among 219 patients in the nonanthracycline group (10%) and 23 events among 219 patients in the anthracycline group (11%). The corresponding 3-year EFS estimates were 93.5% and 92.7%, with a hazard ratio that favored the nonanthracycline group, though the difference between arms was not statistically significant (hazard ratio, 0.90; 95% confidence interval, 0.50-1.63).

“The results were independent of hormone receptor status, age, tumor size, nodal status, and grade, so we found no evidence that high-risk patients require anthracyclines,” said Ms. Van der Voort. Of note, results divided by nodal status suggested similar or better outcomes in the absence of anthracyclines, even in the highest-risk group, she added.

Estimated 3-year overall survival rates were likewise similar between groups, at 98.2% and 97.7% in the nonanthracycline and anthracycline arms, respectively.

Declines in left ventricular ejection fraction were more frequent in the anthracycline group (36% vs. 22% for the nonanthracycline group; P = .0016), and about one-third of patients did not recover that decline. New malignancies were found in 5% of the anthracycline group and 2% of the nonanthracycline group.

The TRAIN-2 study was sponsored by the Netherlands Cancer Institute and Roche. Ms. Van der Voort said she had no relationships to disclose. Dr. Hurwitz reported institutional research funding from multiple pharmaceutical companies including Genentech/Roche.

SOURCE: Van der Voort A et al. ASCO 2020, Abstract 501.

For patients with triple-negative breast cancer (TNBC), 1 year of capecitabine treatment after standard therapy may lead to significantly better disease-free survival (DFS), but not overall survival (OS), according to results of a phase 3 trial.

Patients who received metronomic capecitabine maintenance had significantly higher rates of 5-year DFS and distant DFS, but not OS, when compared with patients who did not receive capecitabine, reported Xi Wang, PhD, of Sun Yat-sen University Cancer Center in Guangzhou, China, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

“TNBC has the worst outcomes among all subtypes of breast cancer,” Dr. Wang said. “Effective strategies to reduce risk of relapse are a critical clinical need.”

He went on to describe capecitabine as a “potential ideal drug for metronomic administration,” particularly among patients with high risk of distant metastasis.

With that in mind, Dr. Wang and colleagues tested metronomic capecitabine maintenance in the phase 3 SYSUCC-001 trial. The trial included 434 patients with invasive ductal carcinoma. They had undergone standard therapy, which included surgery, neoadjuvant/adjuvant chemotherapy, and radiation therapy.

Patients were randomized to receive capecitabine at 650 mg/m² twice daily for 1 year (n = 221) or undergo observation (n = 213). The primary endpoint was DFS, while secondary endpoints included safety, distant DFS, and OS.

According to Dr. Wang, the two patient groups were “well balanced,” with similar baseline characteristics. Most patients underwent adjuvant chemotherapy (93%), had histological grade 3 tumors (71%-74%), had a Ki-67 index of at least 30% (73%-80%), had negative lymph node status (61%-62%), had a tumor size of 2.1-5 cm (55%-58%), and/or pathologic stage II disease (54%-55%).
 

Survival and safety

At a median follow-up of 56.5 months, the median 5-year DFS rate was 83% in the capecitabine group, compared with 73% in the observation group (P = .027). Similarly, capecitabine use correlated with a significantly better rate of distant DFS (85% vs. 76%; P = .016).

Although the capecitabine group demonstrated a slight trend toward improved OS at 5 years, this finding was not statistically significant (86% vs. 81%; P = .203).

Capecitabine was generally well tolerated, with 91% of patients completing 1 year of therapy, and 75% completing therapy at the full dose.

Almost half of patients in the capecitabine group experienced hand-foot syndrome (45%), and one in four developed leukopenia (24%). Less common adverse events included hyperbilirubinemia (13%), gastrointestinal pain (7%), and elevated serum transaminases (5%). No unexpected serious adverse events occurred.
 

Effects on practice

Amy Tiersten, MD, of the Icahn School of Medicine at Mount Sinai in New York, suggested these findings may lead to broader use of capecitabine among patients with TNBC.

“[This is a] very exciting study showing an impressive disease-free survival benefit in the adjuvant setting for capecitabine in patients with early stage TNBC,” Dr. Tiersten said. “Presently, we only have positive data for capecitabine in patients with residual disease after neoadjuvant therapy, but this current study now suggests that this benefit could extend to all comers.”

Dr. Tiersten advised that the medical community stay tuned, since longer-term data may provide a clearer picture of survival benefit.

“It will be interesting to see if there is an impact on overall survival with further follow-up,” she said.

According to invited discussant Naamit Kurshan Gerber, MD, of New York University, the results support previous findings from the CREATE-X trial, along with meta-analyses that have shown a “preferential benefit” of capecitabine when used to treat TNBC, compared with estrogen receptor–positive disease.

Still, Dr. Gerber noted that, for most patients, the findings from the SYSUCC-001 trial are unlikely to influence clinical decision-making since most patients with TNBC receive neoadjuvant chemotherapy followed by treatment based on pathologic response. However, she also suggested that, after peer review, the findings could influence treatment for a select few.

“For the small population of patients who receive adjuvant chemotherapy for higher-stage TNBC and who would have met eligibility criteria, this approach may be considered,” Dr. Gerber said.

The study was funded by the Sun Yat-sen University Clinical Research 5010 Program. The investigators disclosed no conflicts of interest. Dr. Gerber reported a relationship with OncLive. Dr. Tiersten reported no relevant disclosures.

SOURCE: Wang X et al. ASCO 2020, Abstract 507.

For patients with triple-negative breast cancer (TNBC), 1 year of capecitabine treatment after standard therapy may lead to significantly better disease-free survival (DFS), but not overall survival (OS), according to results of a phase 3 trial.

Patients who received metronomic capecitabine maintenance had significantly higher rates of 5-year DFS and distant DFS, but not OS, when compared with patients who did not receive capecitabine, reported Xi Wang, PhD, of Sun Yat-sen University Cancer Center in Guangzhou, China, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

“TNBC has the worst outcomes among all subtypes of breast cancer,” Dr. Wang said. “Effective strategies to reduce risk of relapse are a critical clinical need.”

He went on to describe capecitabine as a “potential ideal drug for metronomic administration,” particularly among patients with high risk of distant metastasis.

With that in mind, Dr. Wang and colleagues tested metronomic capecitabine maintenance in the phase 3 SYSUCC-001 trial. The trial included 434 patients with invasive ductal carcinoma. They had undergone standard therapy, which included surgery, neoadjuvant/adjuvant chemotherapy, and radiation therapy.

Patients were randomized to receive capecitabine at 650 mg/m² twice daily for 1 year (n = 221) or undergo observation (n = 213). The primary endpoint was DFS, while secondary endpoints included safety, distant DFS, and OS.

According to Dr. Wang, the two patient groups were “well balanced,” with similar baseline characteristics. Most patients underwent adjuvant chemotherapy (93%), had histological grade 3 tumors (71%-74%), had a Ki-67 index of at least 30% (73%-80%), had negative lymph node status (61%-62%), had a tumor size of 2.1-5 cm (55%-58%), and/or pathologic stage II disease (54%-55%).
 

Survival and safety

At a median follow-up of 56.5 months, the median 5-year DFS rate was 83% in the capecitabine group, compared with 73% in the observation group (P = .027). Similarly, capecitabine use correlated with a significantly better rate of distant DFS (85% vs. 76%; P = .016).

Although the capecitabine group demonstrated a slight trend toward improved OS at 5 years, this finding was not statistically significant (86% vs. 81%; P = .203).

Capecitabine was generally well tolerated, with 91% of patients completing 1 year of therapy, and 75% completing therapy at the full dose.

Almost half of patients in the capecitabine group experienced hand-foot syndrome (45%), and one in four developed leukopenia (24%). Less common adverse events included hyperbilirubinemia (13%), gastrointestinal pain (7%), and elevated serum transaminases (5%). No unexpected serious adverse events occurred.
 

Effects on practice

Amy Tiersten, MD, of the Icahn School of Medicine at Mount Sinai in New York, suggested these findings may lead to broader use of capecitabine among patients with TNBC.

“[This is a] very exciting study showing an impressive disease-free survival benefit in the adjuvant setting for capecitabine in patients with early stage TNBC,” Dr. Tiersten said. “Presently, we only have positive data for capecitabine in patients with residual disease after neoadjuvant therapy, but this current study now suggests that this benefit could extend to all comers.”

Dr. Tiersten advised that the medical community stay tuned, since longer-term data may provide a clearer picture of survival benefit.

“It will be interesting to see if there is an impact on overall survival with further follow-up,” she said.

According to invited discussant Naamit Kurshan Gerber, MD, of New York University, the results support previous findings from the CREATE-X trial, along with meta-analyses that have shown a “preferential benefit” of capecitabine when used to treat TNBC, compared with estrogen receptor–positive disease.

Still, Dr. Gerber noted that, for most patients, the findings from the SYSUCC-001 trial are unlikely to influence clinical decision-making since most patients with TNBC receive neoadjuvant chemotherapy followed by treatment based on pathologic response. However, she also suggested that, after peer review, the findings could influence treatment for a select few.

“For the small population of patients who receive adjuvant chemotherapy for higher-stage TNBC and who would have met eligibility criteria, this approach may be considered,” Dr. Gerber said.

The study was funded by the Sun Yat-sen University Clinical Research 5010 Program. The investigators disclosed no conflicts of interest. Dr. Gerber reported a relationship with OncLive. Dr. Tiersten reported no relevant disclosures.

SOURCE: Wang X et al. ASCO 2020, Abstract 507.

For patients with triple-negative breast cancer (TNBC), 1 year of capecitabine treatment after standard therapy may lead to significantly better disease-free survival (DFS), but not overall survival (OS), according to results of a phase 3 trial.

Patients who received metronomic capecitabine maintenance had significantly higher rates of 5-year DFS and distant DFS, but not OS, when compared with patients who did not receive capecitabine, reported Xi Wang, PhD, of Sun Yat-sen University Cancer Center in Guangzhou, China, who presented the findings as part of the American Society of Clinical Oncology virtual scientific program.

“TNBC has the worst outcomes among all subtypes of breast cancer,” Dr. Wang said. “Effective strategies to reduce risk of relapse are a critical clinical need.”

He went on to describe capecitabine as a “potential ideal drug for metronomic administration,” particularly among patients with high risk of distant metastasis.

With that in mind, Dr. Wang and colleagues tested metronomic capecitabine maintenance in the phase 3 SYSUCC-001 trial. The trial included 434 patients with invasive ductal carcinoma. They had undergone standard therapy, which included surgery, neoadjuvant/adjuvant chemotherapy, and radiation therapy.

Patients were randomized to receive capecitabine at 650 mg/m² twice daily for 1 year (n = 221) or undergo observation (n = 213). The primary endpoint was DFS, while secondary endpoints included safety, distant DFS, and OS.

According to Dr. Wang, the two patient groups were “well balanced,” with similar baseline characteristics. Most patients underwent adjuvant chemotherapy (93%), had histological grade 3 tumors (71%-74%), had a Ki-67 index of at least 30% (73%-80%), had negative lymph node status (61%-62%), had a tumor size of 2.1-5 cm (55%-58%), and/or pathologic stage II disease (54%-55%).
 

Survival and safety

At a median follow-up of 56.5 months, the median 5-year DFS rate was 83% in the capecitabine group, compared with 73% in the observation group (P = .027). Similarly, capecitabine use correlated with a significantly better rate of distant DFS (85% vs. 76%; P = .016).

Although the capecitabine group demonstrated a slight trend toward improved OS at 5 years, this finding was not statistically significant (86% vs. 81%; P = .203).

Capecitabine was generally well tolerated, with 91% of patients completing 1 year of therapy, and 75% completing therapy at the full dose.

Almost half of patients in the capecitabine group experienced hand-foot syndrome (45%), and one in four developed leukopenia (24%). Less common adverse events included hyperbilirubinemia (13%), gastrointestinal pain (7%), and elevated serum transaminases (5%). No unexpected serious adverse events occurred.
 

Effects on practice

Amy Tiersten, MD, of the Icahn School of Medicine at Mount Sinai in New York, suggested these findings may lead to broader use of capecitabine among patients with TNBC.

“[This is a] very exciting study showing an impressive disease-free survival benefit in the adjuvant setting for capecitabine in patients with early stage TNBC,” Dr. Tiersten said. “Presently, we only have positive data for capecitabine in patients with residual disease after neoadjuvant therapy, but this current study now suggests that this benefit could extend to all comers.”

Dr. Tiersten advised that the medical community stay tuned, since longer-term data may provide a clearer picture of survival benefit.

“It will be interesting to see if there is an impact on overall survival with further follow-up,” she said.

According to invited discussant Naamit Kurshan Gerber, MD, of New York University, the results support previous findings from the CREATE-X trial, along with meta-analyses that have shown a “preferential benefit” of capecitabine when used to treat TNBC, compared with estrogen receptor–positive disease.

Still, Dr. Gerber noted that, for most patients, the findings from the SYSUCC-001 trial are unlikely to influence clinical decision-making since most patients with TNBC receive neoadjuvant chemotherapy followed by treatment based on pathologic response. However, she also suggested that, after peer review, the findings could influence treatment for a select few.

“For the small population of patients who receive adjuvant chemotherapy for higher-stage TNBC and who would have met eligibility criteria, this approach may be considered,” Dr. Gerber said.

The study was funded by the Sun Yat-sen University Clinical Research 5010 Program. The investigators disclosed no conflicts of interest. Dr. Gerber reported a relationship with OncLive. Dr. Tiersten reported no relevant disclosures.

SOURCE: Wang X et al. ASCO 2020, Abstract 507.

The proton pump inhibitor (PPI) omeprazole may be a useful addition to treatment for triple-negative breast cancer, as it boosted the expected rate of tumor disappearance among women with early-stage disease, according to the results of a phase 2 trial.

The trial results are presented online at the 2020 virtual annual meeting of the American Society of Clinical Oncology.

The rationale behind the approach includes the fact that PPIs inhibit fatty acid synthase (FASN), an enzyme overexpressed in 70% of newly diagnosed triple-negative breast cancers (TNBC) and associated with poor prognosis.

In the study, omeprazole, a generic drug for gastroesophageal reflux, was added to standard chemotherapy. Both were given to 42 women as neoadjuvant treatment in the weeks before breast surgery at five US centers in the single-arm study.

The pathologic complete response (pCR) rate was 71% in the study population, which is higher than the typical 40% seen in patients treated with standard AC-T (adriamycin and cyclophosphamide plus a taxane), said lead author Sagar D. Sardesai, MBBS, a medical oncologist at Ohio State Comprehensive Cancer Center in Columbus.

“It’s exciting,” said Dr. Sardesai in an interview. “Overall, triple-negative patients who achieve a pCR have a very good outcome.”

That complete disappearance of the tumor is a surrogate for overall survival in TNBC, and patients who achieve it have a greatly reduced risk of recurrence or death, he explained.

Natalie Berger, MD, medical oncologist, Icahn School of Medicine at Mount Sinai, New York City, said the study’s pCR rates were “much higher” than expected and “intriguing and hypothesis generating.”

But Dr. Berger, who was not involved in the study, wanted to see more data.

“Having a non-chemotherapeutic agent to offer our patients with TNBC that improves pCR rates without added toxicity would be an exciting finding, but we need a larger randomized study,” she said in an email.

The researchers, who include high-profile breast cancer specialist Kathy Miller, MD, of Indiana University, are seeking a National Cancer Institute or Department of Defense grant to mount a 100-plus patient randomized trial.
 

Potential Drug Target for Some Years

Dr. Sardesai explained that FASN, which is an enzyme, helps generate fatty acids that are a key to cancer cell survival. FASN is primarily found in hormone-dominated tissue such as those of the endometrium, prostate, and breast.

PPIs “selectively inhibit FASN activity and induce apoptosis in breast cancer cell lines with minimal effect on non-malignant cells,” wrote the study authors in their meeting abstract.

The only other known agent known to inhibit FASN is the weight loss drug orlistat, which is poorly absorbed by the body and unlikely to impact cancer cells, Dr. Sardesai said.

FASN has been a potential drug target in TNBC for 10 to 15 years, but the first clinical evidence of efficacy in solid tumors was only seen in the last 5 years, he commented.

In 2015, Chinese investigators reported that the PPI esomeprazole in combination with chemotherapy produced a 5-month improvement in progression-free survival (vs. chemo alone) among a subset of 15 TNBC patients in a randomized trial of 94 patients with a variety of breast cancer types.
 

No Added Toxicity, But Some Unexpected Findings

The study was conducted in patients with early-stage, operable TNBC (with and without baseline FASN expression) and no prior PPI use within 12 months.

All patients started daily high-dose omeprazole 4 to 7 days prior to start of AC-T neoadjuvant chemotherapy (the addition of carboplatin was allowed per physician discretion) and continued until surgery.

The primary endpoint was pCR, defined as no residual invasive disease in breast or axilla, in patients with baseline FASN expression (FASN+). The pCR rate was 71.4% in the 28 FASN+ patients and 71.8% in all 42 enrolled patients. The researchers had targeted a pCR rate of 60% in the FASN+ patients. Also, among the subset of 15 patients who received carboplatin with AC-T, the pCR was 73%.

These two findings both have limitations, commented Dr. Berger. She pointed out that it is “unexplained” as to why the pCR rates were similar among the FASN+ patients and the total population (including 14 FASN– patients); the pCR rate would be expected to be lower in the total population, she suggested.

Further, it was also unexplained as to why there were similar pCR rates with or without carboplatin; other research has demonstrated improved pCR rates in patients receiving additional carboplatin (compared to AC-T alone) but at the cost of increased toxicity, she said.

Dr. Sardesai said that omeprazole was well tolerated with no known grade 3 or 4 toxicities and that the chemotherapy toxicity was similar to prior studies of AC-T. PPIs have side effects if taken for longer than a year, including a higher risk of infections, osteoporosis, and low magnesium, he also commented.

“Omeprazole can be safely administered in doses that inhibit FASN. The addition of high-dose omeprazole to neoadjuvant AC-T yields a promising pCR rate without adding toxicity,” the authors concluded in their abstract.

Dr. Sardesai also highlighted the fact that using a PPI for breast cancer is an example of drug repurposing. The approach offers a way of rapid drug development because PPIs have complete safety and pharmacokinetics data available, he said. “If we can prove the efficacy, the treatment can move forward quickly and be available in clinical practice much sooner than with traditional drug development.”

The study was funded by the Breast Cancer Research Foundation. Dr. Sardesai disclosed financial ties to Novartis and Immunomedics. Other study authors have ties to industry. Dr. Berger disclosed no relevant financial relationships.

This article first appeared on Medscape.com.

The proton pump inhibitor (PPI) omeprazole may be a useful addition to treatment for triple-negative breast cancer, as it boosted the expected rate of tumor disappearance among women with early-stage disease, according to the results of a phase 2 trial.

The trial results are presented online at the 2020 virtual annual meeting of the American Society of Clinical Oncology.

The rationale behind the approach includes the fact that PPIs inhibit fatty acid synthase (FASN), an enzyme overexpressed in 70% of newly diagnosed triple-negative breast cancers (TNBC) and associated with poor prognosis.

In the study, omeprazole, a generic drug for gastroesophageal reflux, was added to standard chemotherapy. Both were given to 42 women as neoadjuvant treatment in the weeks before breast surgery at five US centers in the single-arm study.

The pathologic complete response (pCR) rate was 71% in the study population, which is higher than the typical 40% seen in patients treated with standard AC-T (adriamycin and cyclophosphamide plus a taxane), said lead author Sagar D. Sardesai, MBBS, a medical oncologist at Ohio State Comprehensive Cancer Center in Columbus.

“It’s exciting,” said Dr. Sardesai in an interview. “Overall, triple-negative patients who achieve a pCR have a very good outcome.”

That complete disappearance of the tumor is a surrogate for overall survival in TNBC, and patients who achieve it have a greatly reduced risk of recurrence or death, he explained.

Natalie Berger, MD, medical oncologist, Icahn School of Medicine at Mount Sinai, New York City, said the study’s pCR rates were “much higher” than expected and “intriguing and hypothesis generating.”

But Dr. Berger, who was not involved in the study, wanted to see more data.

“Having a non-chemotherapeutic agent to offer our patients with TNBC that improves pCR rates without added toxicity would be an exciting finding, but we need a larger randomized study,” she said in an email.

The researchers, who include high-profile breast cancer specialist Kathy Miller, MD, of Indiana University, are seeking a National Cancer Institute or Department of Defense grant to mount a 100-plus patient randomized trial.
 

Potential Drug Target for Some Years

Dr. Sardesai explained that FASN, which is an enzyme, helps generate fatty acids that are a key to cancer cell survival. FASN is primarily found in hormone-dominated tissue such as those of the endometrium, prostate, and breast.

PPIs “selectively inhibit FASN activity and induce apoptosis in breast cancer cell lines with minimal effect on non-malignant cells,” wrote the study authors in their meeting abstract.

The only other known agent known to inhibit FASN is the weight loss drug orlistat, which is poorly absorbed by the body and unlikely to impact cancer cells, Dr. Sardesai said.

FASN has been a potential drug target in TNBC for 10 to 15 years, but the first clinical evidence of efficacy in solid tumors was only seen in the last 5 years, he commented.

In 2015, Chinese investigators reported that the PPI esomeprazole in combination with chemotherapy produced a 5-month improvement in progression-free survival (vs. chemo alone) among a subset of 15 TNBC patients in a randomized trial of 94 patients with a variety of breast cancer types.
 

No Added Toxicity, But Some Unexpected Findings

The study was conducted in patients with early-stage, operable TNBC (with and without baseline FASN expression) and no prior PPI use within 12 months.

All patients started daily high-dose omeprazole 4 to 7 days prior to start of AC-T neoadjuvant chemotherapy (the addition of carboplatin was allowed per physician discretion) and continued until surgery.

The primary endpoint was pCR, defined as no residual invasive disease in breast or axilla, in patients with baseline FASN expression (FASN+). The pCR rate was 71.4% in the 28 FASN+ patients and 71.8% in all 42 enrolled patients. The researchers had targeted a pCR rate of 60% in the FASN+ patients. Also, among the subset of 15 patients who received carboplatin with AC-T, the pCR was 73%.

These two findings both have limitations, commented Dr. Berger. She pointed out that it is “unexplained” as to why the pCR rates were similar among the FASN+ patients and the total population (including 14 FASN– patients); the pCR rate would be expected to be lower in the total population, she suggested.

Further, it was also unexplained as to why there were similar pCR rates with or without carboplatin; other research has demonstrated improved pCR rates in patients receiving additional carboplatin (compared to AC-T alone) but at the cost of increased toxicity, she said.

Dr. Sardesai said that omeprazole was well tolerated with no known grade 3 or 4 toxicities and that the chemotherapy toxicity was similar to prior studies of AC-T. PPIs have side effects if taken for longer than a year, including a higher risk of infections, osteoporosis, and low magnesium, he also commented.

“Omeprazole can be safely administered in doses that inhibit FASN. The addition of high-dose omeprazole to neoadjuvant AC-T yields a promising pCR rate without adding toxicity,” the authors concluded in their abstract.

Dr. Sardesai also highlighted the fact that using a PPI for breast cancer is an example of drug repurposing. The approach offers a way of rapid drug development because PPIs have complete safety and pharmacokinetics data available, he said. “If we can prove the efficacy, the treatment can move forward quickly and be available in clinical practice much sooner than with traditional drug development.”

The study was funded by the Breast Cancer Research Foundation. Dr. Sardesai disclosed financial ties to Novartis and Immunomedics. Other study authors have ties to industry. Dr. Berger disclosed no relevant financial relationships.

This article first appeared on Medscape.com.

The proton pump inhibitor (PPI) omeprazole may be a useful addition to treatment for triple-negative breast cancer, as it boosted the expected rate of tumor disappearance among women with early-stage disease, according to the results of a phase 2 trial.

The trial results are presented online at the 2020 virtual annual meeting of the American Society of Clinical Oncology.

The rationale behind the approach includes the fact that PPIs inhibit fatty acid synthase (FASN), an enzyme overexpressed in 70% of newly diagnosed triple-negative breast cancers (TNBC) and associated with poor prognosis.

In the study, omeprazole, a generic drug for gastroesophageal reflux, was added to standard chemotherapy. Both were given to 42 women as neoadjuvant treatment in the weeks before breast surgery at five US centers in the single-arm study.

The pathologic complete response (pCR) rate was 71% in the study population, which is higher than the typical 40% seen in patients treated with standard AC-T (adriamycin and cyclophosphamide plus a taxane), said lead author Sagar D. Sardesai, MBBS, a medical oncologist at Ohio State Comprehensive Cancer Center in Columbus.

“It’s exciting,” said Dr. Sardesai in an interview. “Overall, triple-negative patients who achieve a pCR have a very good outcome.”

That complete disappearance of the tumor is a surrogate for overall survival in TNBC, and patients who achieve it have a greatly reduced risk of recurrence or death, he explained.

Natalie Berger, MD, medical oncologist, Icahn School of Medicine at Mount Sinai, New York City, said the study’s pCR rates were “much higher” than expected and “intriguing and hypothesis generating.”

But Dr. Berger, who was not involved in the study, wanted to see more data.

“Having a non-chemotherapeutic agent to offer our patients with TNBC that improves pCR rates without added toxicity would be an exciting finding, but we need a larger randomized study,” she said in an email.

The researchers, who include high-profile breast cancer specialist Kathy Miller, MD, of Indiana University, are seeking a National Cancer Institute or Department of Defense grant to mount a 100-plus patient randomized trial.
 

Potential Drug Target for Some Years

Dr. Sardesai explained that FASN, which is an enzyme, helps generate fatty acids that are a key to cancer cell survival. FASN is primarily found in hormone-dominated tissue such as those of the endometrium, prostate, and breast.

PPIs “selectively inhibit FASN activity and induce apoptosis in breast cancer cell lines with minimal effect on non-malignant cells,” wrote the study authors in their meeting abstract.

The only other known agent known to inhibit FASN is the weight loss drug orlistat, which is poorly absorbed by the body and unlikely to impact cancer cells, Dr. Sardesai said.

FASN has been a potential drug target in TNBC for 10 to 15 years, but the first clinical evidence of efficacy in solid tumors was only seen in the last 5 years, he commented.

In 2015, Chinese investigators reported that the PPI esomeprazole in combination with chemotherapy produced a 5-month improvement in progression-free survival (vs. chemo alone) among a subset of 15 TNBC patients in a randomized trial of 94 patients with a variety of breast cancer types.
 

No Added Toxicity, But Some Unexpected Findings

The study was conducted in patients with early-stage, operable TNBC (with and without baseline FASN expression) and no prior PPI use within 12 months.

All patients started daily high-dose omeprazole 4 to 7 days prior to start of AC-T neoadjuvant chemotherapy (the addition of carboplatin was allowed per physician discretion) and continued until surgery.

The primary endpoint was pCR, defined as no residual invasive disease in breast or axilla, in patients with baseline FASN expression (FASN+). The pCR rate was 71.4% in the 28 FASN+ patients and 71.8% in all 42 enrolled patients. The researchers had targeted a pCR rate of 60% in the FASN+ patients. Also, among the subset of 15 patients who received carboplatin with AC-T, the pCR was 73%.

These two findings both have limitations, commented Dr. Berger. She pointed out that it is “unexplained” as to why the pCR rates were similar among the FASN+ patients and the total population (including 14 FASN– patients); the pCR rate would be expected to be lower in the total population, she suggested.

Further, it was also unexplained as to why there were similar pCR rates with or without carboplatin; other research has demonstrated improved pCR rates in patients receiving additional carboplatin (compared to AC-T alone) but at the cost of increased toxicity, she said.

Dr. Sardesai said that omeprazole was well tolerated with no known grade 3 or 4 toxicities and that the chemotherapy toxicity was similar to prior studies of AC-T. PPIs have side effects if taken for longer than a year, including a higher risk of infections, osteoporosis, and low magnesium, he also commented.

“Omeprazole can be safely administered in doses that inhibit FASN. The addition of high-dose omeprazole to neoadjuvant AC-T yields a promising pCR rate without adding toxicity,” the authors concluded in their abstract.

Dr. Sardesai also highlighted the fact that using a PPI for breast cancer is an example of drug repurposing. The approach offers a way of rapid drug development because PPIs have complete safety and pharmacokinetics data available, he said. “If we can prove the efficacy, the treatment can move forward quickly and be available in clinical practice much sooner than with traditional drug development.”

The study was funded by the Breast Cancer Research Foundation. Dr. Sardesai disclosed financial ties to Novartis and Immunomedics. Other study authors have ties to industry. Dr. Berger disclosed no relevant financial relationships.

This article first appeared on Medscape.com.

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.

Adding pembrolizumab to standard chemotherapy significantly improved progression-free survival for patients with metastatic triple-negative breast cancer, but only if their tumors were enriched with comparatively high levels of the target programmed death ligand-1 (PD-L1), results of the KEYNOTE 355 trial showed.

Among 843 patients with triple-negative breast cancer (TNBC) randomized to receive either investigator’s choice of chemotherapy plus pembrolizumab (Keytruda) or placebo, patients whose tumors had a PD-L1 combined positive score (CPS) of 10 or higher had a median progression-free survival (PFS) of 9.7 months when treated with pembrolizumab and chemotherapy, compared with 5.6 months among patients treated with chemotherapy and placebo, reported Javier Cortes, MD, PhD, from the Vall d´Hebron Institute of Oncology in Madrid and Barcelona.

However, among patients with CPS between 1 and 10, there was no significant difference in PFS between the treatment arms, he said in a presentation made as a part of the 2020 American Society of Clinical Oncology virtual scientific program.

“The inclusion of taxanes and a known taxane/platinum–based regimen permits assessment of the clinical benefit of pembro in combination with several routinely used chemo partners. A trend toward improved efficacy with PD-L1 enrichment was observed in patients treated with pembro plus chemo. The improvement in progression-free survival with chemotherapy and pembrolizumab was observed across patient subgroups,” said Dr. Cortes.

In the KEYNOTE-522 study, adding pembrolizumab to chemotherapy in the neoadjuvant setting increased the likelihood that women with stage III or early node-positive TNBC would have a pathologic complete response and sustained clinical benefit.

KEYNOTE-355 examined whether pembrolizumab in combination with chemotherapy could provide additional benefit over chemotherapy alone in patients with previously untreated locally recurrent inoperable or metastatic TNBC.

Patients with previously untreated metastatic triple-negative breast cancer who had at least 6 months between definite surgery or last dose of adjuvant chemotherapy (whichever came last) and first disease recurrence were stratified by study chemotherapy received, tumor PD-L1 expression at baseline, and prior treatment with the same class of chemotherapy in the neoadjuvant and/or adjuvant setting.

The patients were then randomized in a 2:1 ratio to pembrolizumab plus chemotherapy based on the investigator’s choice of nab-paclitaxel, paclitaxel, or carboplatin-gemcitabine (562 patients) or to chemotherapy alone (281).

Pembrolizumab and placebo were administered in a double-blind fashion for up to 35 doses. Chemotherapy was given at the investigator’s discretion according to local guidelines. This trial was not powered or designed to compare differential efficacy of the various chemotherapy regimens, Dr. Cortes noted.

The trial had dual primary endpoints of PFS in patients with PD-L1–positive tumors (CPS > 10 and > 1) and in the intention-to-treat population, and overall survival both in PD-L1-positive patients and the ITT population. Overall survival results will be reported at a later date.

As noted before, the primary endpoint was met in the population of patients with CPS higher than 10, with median PFS of 9.7 among those receiving pembrolizumab versus 5.6 months among those receiving placebo, and an estimated 1 year PFS of 39.1% versus 23% for controls, translating into a hazard ratio for progression on pembrolizumab of 0.65 (P = .0012).

In the patients with CPS higher than 1, however, the median PFS was 7.6 months with pembrolizumab compared with 5.6 months with placebo, translating into a hazard ratio of 0.74. However, the results did not meet the prespecified boundary for significance. Because of this, the statistical significance in the ITT population was not tested.

“In patients with PD-L1 CPS 10 or higher tumors, the benefit of pembro/chemo on progression-free survival was generally consistent across most predefined subgroups, including eight geographic regions, ECOG performance status, on-study chemo, and prior treatment with the same class of chemo,” Dr. Cortes said.

Treatment-related adverse events occurred in 96.3% of the patients on pembrolizumab and 95% of patients on placebo. Grade 3 or greater adverse events occurred in 68.1% versus 66.9%, respectively. Two patients in the pembrolizumab arm died from a treatment-related event. There were no treatment-related deaths in the placebo arm.

The most common events were those typically associated with chemotherapy, including anemia, neutropenia, nausea, alopecia, fatigue, decreased neutrophil counts, and elevated liver transaminases. Immune-mediated adverse events of any grade occurred in 25.6% of patients in the pembrolizumab arm versus 6% of controls; none of these events were fatal.

“What is clear in this study is that again we’re seeing efficacy of pembrolizumab in combination with chemotherapy increases with increases in CPS,” according to the invited discussant Catherine M. Kelly, MB, BCh, from University College Dublin and Mater Misericordiae University Hospital in Dublin.

“The results from today’s KEYNOTE-355 appear consistent in terms of progression-free survival. However, it is ‘watch this space’ until we get overall survival data before we can make any further comparisons,” she added.

Questions that still need to be answered include which is the best test for measuring PD-L1, whether patients with CPS of 1 or more but less than 10 benefit from the treatment, which of the available chemotherapy regimens is the best partner for pembrolizumab, how to treat patients who don’t respond to the combination, and what are the implications for PD-1/PD-L1 inhibitors in late-stage disease if they are approved in the neoadjuvant or adjuvant setting, Dr. Kelly said.

The study was funded by Merck. Dr. Cortes disclosed honoraria from, a consulting/advisory role for, and institutional research funding from Merck and others. Dr. Kelly disclosed honoraria from MSD Oncology and others, and travel expenses from Pfizer and Roche.

SOURCE: Cortes J et al. ASCO 2020, Abstract 1000.