TBD Meeting (5265-17)

LUGANO, SWITZERLAND – Patients with relapsed/refractory primary mediastinal large B-cell lymphoma (PMBCL) have few good therapeutic options, but pembrolizumab (Keytruda) may be one of them, an interim analysis from a phase 2 trial suggests.

Six of 10 patients with relapsed/refractory PMBCL for whom autologous stem cell transplantation (ASCT) had failed had responses to salvage therapy with pembrolizumab, including three complete responses (CR) and three partial responses (PR), reported Pier Luigi Zinzani, MD, PhD, of the University of Bologna, Italy.

“In relapsed/refractory primary mediastinal large B-cell lymphoma including heavily pretreated patients in our series, pembrolizumab showed promising antitumor activity in these preliminary data from a phase 2 study, and a manageable safety profile,” Dr. Zinzani said at the International Conference on Malignant Lymphoma.

Neil Osterweil/Frontline Medical News

LUGANO, SWITZERLAND – Patients with relapsed/refractory primary mediastinal large B-cell lymphoma (PMBCL) have few good therapeutic options, but pembrolizumab (Keytruda) may be one of them, an interim analysis from a phase 2 trial suggests.

Six of 10 patients with relapsed/refractory PMBCL for whom autologous stem cell transplantation (ASCT) had failed had responses to salvage therapy with pembrolizumab, including three complete responses (CR) and three partial responses (PR), reported Pier Luigi Zinzani, MD, PhD, of the University of Bologna, Italy.

“In relapsed/refractory primary mediastinal large B-cell lymphoma including heavily pretreated patients in our series, pembrolizumab showed promising antitumor activity in these preliminary data from a phase 2 study, and a manageable safety profile,” Dr. Zinzani said at the International Conference on Malignant Lymphoma.

Neil Osterweil/Frontline Medical News

LUGANO, SWITZERLAND – Patients with relapsed/refractory primary mediastinal large B-cell lymphoma (PMBCL) have few good therapeutic options, but pembrolizumab (Keytruda) may be one of them, an interim analysis from a phase 2 trial suggests.

Six of 10 patients with relapsed/refractory PMBCL for whom autologous stem cell transplantation (ASCT) had failed had responses to salvage therapy with pembrolizumab, including three complete responses (CR) and three partial responses (PR), reported Pier Luigi Zinzani, MD, PhD, of the University of Bologna, Italy.

“In relapsed/refractory primary mediastinal large B-cell lymphoma including heavily pretreated patients in our series, pembrolizumab showed promising antitumor activity in these preliminary data from a phase 2 study, and a manageable safety profile,” Dr. Zinzani said at the International Conference on Malignant Lymphoma.

Neil Osterweil/Frontline Medical News

LUGANO, SWITZERLAND – The immune checkpoint inhibitor avelumab showed efficacy against classical Hodgkin lymphoma among patients with disease progression following allogeneic stem cell transplants (allo-SCT), based on results of a phase 1 trial.

Two of eight patients with disease progression following an allogeneic transplant (allo-SCT) had complete responses (CR) to the programmed death ligand-1 (PD-L1) inhibitor avelumab (Bavencio), three had partial responses (PRs), and two had stable disease, reported Robert Chen, MD, of City of Hope Medical Center in Duarte, California.

“The overall response rate observed in the postallo population of 62.5% suggests that the PD-L1 blockade inhibitor may potentiate a graft-vs.-lymphoma response,” he said at the 14th International Conference on Malignant Lymphoma.

Amplification of the chromosome 9p24.1 locus is frequent in classical Hodgkin lymphoma, and the amplicon contains the genes encoding for PD-L1 and PD-L2, resulting in the over expression of both ligands, Dr. Chen said.

Both nivolumab (Opdivo) and pembrolizumab (Keytruda) are indicated for the treatment of relapsed/refractory classical Hodgkin lymphoma. Both agents block the interactions between PD-1 and both PD-L1 and PD-L2.

“However, it has not been established whether blockade of the PD-1/PD-L1 interaction is necessary and/or sufficient for the therapeutic effect observed in classical Hodgkin lymphoma,” he said.

Avelumab is an anti–PD-L1, immunoglobulin G1 monoclonal antibody that inhibits PD-1/PD-L1 interactions but leaves PD-1/PD-L2 interactions intact. This agent, which recently received FDA approval for the treatment of Merkel cell carcinoma and locally advanced or metastatic urothelial carcinoma, targets tumor cells rather than the T cells targeted by nivolumab and pembrolizumab.

In the phase 1b JAVELIN Hodgkin study, patients with histologically confirmed relapsed/refractory classical Hodgkin lymphoma who were ineligible for transplant or for whom allogeneic or autologous stem cell transplants had failed were enrolled and were assigned to one of five cohorts to receive avelumab in doses ranging from 70 mg intravenously to 10 mg/kg IV every 2 weeks (or every 3 weeks for the 500 mg dose cohort).

A total of 31 patients were randomized in the dose-finding phase of the study. The median patient age was 38 years, 24 patients were younger than 65, and 7 were 65 or older. Only 1 of the 31 patients had received a single prior line of therapy. Of those, 3 had received two prior therapies, 7 had been treated with three prior lines, and 20 had four or more prior lines of therapy. All patients had received brentuximab vedotin (Adcetris).

The median follow-up was 43.3 weeks. In all, nine patients were continuing on avelumab at the time of the data analysis. Because of disease progression, 10 patients discontinued therapy. Additionally, four discontinued because of adverse events, two chose to withdraw, one was removed from the study by the treating physicians, one did not receive treatment, and four others discontinued because of unspecified reasons.

The median treatment duration was 16.9 weeks. The mean number of cycles was 8.6.

The objective response rate was 42%, including five CRs and eight PRs. Three of the CRs were in patients treated at the 70 mg every 2 week dose, and two were in patients treated at the 500 mg every 3 week level.

In all, 23 patients experienced some degree of tumor shrinkage, and 13 had shrinkage greater than 50%.

In an analysis of best overall response among patients whose disease progressed following SCT, the investigators found that two of eight patients (25%) who had disease progression following allo-SCT had a complete response. Three of these patients had a PR, two had stable disease, and one was not eligible for response evaluation.

In contrast, there was only one objective response, a PR, among five patients who had relapses following autologous SCT.

Grade 3 or 4 treatment-related adverse events occurred in 37% of patients. There were no treatment-related deaths. The incidence of treatment-related adverse events was similar across the five dosing cohorts.

“Based on the observed efficacy and safety profiles and unmet need, this study has recently been amended to focus the expansion of patients who progressed post allo-SCT,” Dr. Chen said.

The study was sponsored by Pfizer in collaboration with Merck KGaA, Germany. Dr. Chen has consulted and served in a speakers’ bureau for Seattle Genetics, Millennium, and Genentech. He has also received research funding from Pharmacyclics, Seattle Genetics, Millennium, and Merck.

LUGANO, SWITZERLAND – The immune checkpoint inhibitor avelumab showed efficacy against classical Hodgkin lymphoma among patients with disease progression following allogeneic stem cell transplants (allo-SCT), based on results of a phase 1 trial.

Two of eight patients with disease progression following an allogeneic transplant (allo-SCT) had complete responses (CR) to the programmed death ligand-1 (PD-L1) inhibitor avelumab (Bavencio), three had partial responses (PRs), and two had stable disease, reported Robert Chen, MD, of City of Hope Medical Center in Duarte, California.

“The overall response rate observed in the postallo population of 62.5% suggests that the PD-L1 blockade inhibitor may potentiate a graft-vs.-lymphoma response,” he said at the 14th International Conference on Malignant Lymphoma.

Amplification of the chromosome 9p24.1 locus is frequent in classical Hodgkin lymphoma, and the amplicon contains the genes encoding for PD-L1 and PD-L2, resulting in the over expression of both ligands, Dr. Chen said.

Both nivolumab (Opdivo) and pembrolizumab (Keytruda) are indicated for the treatment of relapsed/refractory classical Hodgkin lymphoma. Both agents block the interactions between PD-1 and both PD-L1 and PD-L2.

“However, it has not been established whether blockade of the PD-1/PD-L1 interaction is necessary and/or sufficient for the therapeutic effect observed in classical Hodgkin lymphoma,” he said.

Avelumab is an anti–PD-L1, immunoglobulin G1 monoclonal antibody that inhibits PD-1/PD-L1 interactions but leaves PD-1/PD-L2 interactions intact. This agent, which recently received FDA approval for the treatment of Merkel cell carcinoma and locally advanced or metastatic urothelial carcinoma, targets tumor cells rather than the T cells targeted by nivolumab and pembrolizumab.

In the phase 1b JAVELIN Hodgkin study, patients with histologically confirmed relapsed/refractory classical Hodgkin lymphoma who were ineligible for transplant or for whom allogeneic or autologous stem cell transplants had failed were enrolled and were assigned to one of five cohorts to receive avelumab in doses ranging from 70 mg intravenously to 10 mg/kg IV every 2 weeks (or every 3 weeks for the 500 mg dose cohort).

A total of 31 patients were randomized in the dose-finding phase of the study. The median patient age was 38 years, 24 patients were younger than 65, and 7 were 65 or older. Only 1 of the 31 patients had received a single prior line of therapy. Of those, 3 had received two prior therapies, 7 had been treated with three prior lines, and 20 had four or more prior lines of therapy. All patients had received brentuximab vedotin (Adcetris).

The median follow-up was 43.3 weeks. In all, nine patients were continuing on avelumab at the time of the data analysis. Because of disease progression, 10 patients discontinued therapy. Additionally, four discontinued because of adverse events, two chose to withdraw, one was removed from the study by the treating physicians, one did not receive treatment, and four others discontinued because of unspecified reasons.

The median treatment duration was 16.9 weeks. The mean number of cycles was 8.6.

The objective response rate was 42%, including five CRs and eight PRs. Three of the CRs were in patients treated at the 70 mg every 2 week dose, and two were in patients treated at the 500 mg every 3 week level.

In all, 23 patients experienced some degree of tumor shrinkage, and 13 had shrinkage greater than 50%.

In an analysis of best overall response among patients whose disease progressed following SCT, the investigators found that two of eight patients (25%) who had disease progression following allo-SCT had a complete response. Three of these patients had a PR, two had stable disease, and one was not eligible for response evaluation.

In contrast, there was only one objective response, a PR, among five patients who had relapses following autologous SCT.

Grade 3 or 4 treatment-related adverse events occurred in 37% of patients. There were no treatment-related deaths. The incidence of treatment-related adverse events was similar across the five dosing cohorts.

“Based on the observed efficacy and safety profiles and unmet need, this study has recently been amended to focus the expansion of patients who progressed post allo-SCT,” Dr. Chen said.

The study was sponsored by Pfizer in collaboration with Merck KGaA, Germany. Dr. Chen has consulted and served in a speakers’ bureau for Seattle Genetics, Millennium, and Genentech. He has also received research funding from Pharmacyclics, Seattle Genetics, Millennium, and Merck.

LUGANO, SWITZERLAND – The immune checkpoint inhibitor avelumab showed efficacy against classical Hodgkin lymphoma among patients with disease progression following allogeneic stem cell transplants (allo-SCT), based on results of a phase 1 trial.

Two of eight patients with disease progression following an allogeneic transplant (allo-SCT) had complete responses (CR) to the programmed death ligand-1 (PD-L1) inhibitor avelumab (Bavencio), three had partial responses (PRs), and two had stable disease, reported Robert Chen, MD, of City of Hope Medical Center in Duarte, California.

“The overall response rate observed in the postallo population of 62.5% suggests that the PD-L1 blockade inhibitor may potentiate a graft-vs.-lymphoma response,” he said at the 14th International Conference on Malignant Lymphoma.

Amplification of the chromosome 9p24.1 locus is frequent in classical Hodgkin lymphoma, and the amplicon contains the genes encoding for PD-L1 and PD-L2, resulting in the over expression of both ligands, Dr. Chen said.

Both nivolumab (Opdivo) and pembrolizumab (Keytruda) are indicated for the treatment of relapsed/refractory classical Hodgkin lymphoma. Both agents block the interactions between PD-1 and both PD-L1 and PD-L2.

“However, it has not been established whether blockade of the PD-1/PD-L1 interaction is necessary and/or sufficient for the therapeutic effect observed in classical Hodgkin lymphoma,” he said.

Avelumab is an anti–PD-L1, immunoglobulin G1 monoclonal antibody that inhibits PD-1/PD-L1 interactions but leaves PD-1/PD-L2 interactions intact. This agent, which recently received FDA approval for the treatment of Merkel cell carcinoma and locally advanced or metastatic urothelial carcinoma, targets tumor cells rather than the T cells targeted by nivolumab and pembrolizumab.

In the phase 1b JAVELIN Hodgkin study, patients with histologically confirmed relapsed/refractory classical Hodgkin lymphoma who were ineligible for transplant or for whom allogeneic or autologous stem cell transplants had failed were enrolled and were assigned to one of five cohorts to receive avelumab in doses ranging from 70 mg intravenously to 10 mg/kg IV every 2 weeks (or every 3 weeks for the 500 mg dose cohort).

A total of 31 patients were randomized in the dose-finding phase of the study. The median patient age was 38 years, 24 patients were younger than 65, and 7 were 65 or older. Only 1 of the 31 patients had received a single prior line of therapy. Of those, 3 had received two prior therapies, 7 had been treated with three prior lines, and 20 had four or more prior lines of therapy. All patients had received brentuximab vedotin (Adcetris).

The median follow-up was 43.3 weeks. In all, nine patients were continuing on avelumab at the time of the data analysis. Because of disease progression, 10 patients discontinued therapy. Additionally, four discontinued because of adverse events, two chose to withdraw, one was removed from the study by the treating physicians, one did not receive treatment, and four others discontinued because of unspecified reasons.

The median treatment duration was 16.9 weeks. The mean number of cycles was 8.6.

The objective response rate was 42%, including five CRs and eight PRs. Three of the CRs were in patients treated at the 70 mg every 2 week dose, and two were in patients treated at the 500 mg every 3 week level.

In all, 23 patients experienced some degree of tumor shrinkage, and 13 had shrinkage greater than 50%.

In an analysis of best overall response among patients whose disease progressed following SCT, the investigators found that two of eight patients (25%) who had disease progression following allo-SCT had a complete response. Three of these patients had a PR, two had stable disease, and one was not eligible for response evaluation.

In contrast, there was only one objective response, a PR, among five patients who had relapses following autologous SCT.

Grade 3 or 4 treatment-related adverse events occurred in 37% of patients. There were no treatment-related deaths. The incidence of treatment-related adverse events was similar across the five dosing cohorts.

“Based on the observed efficacy and safety profiles and unmet need, this study has recently been amended to focus the expansion of patients who progressed post allo-SCT,” Dr. Chen said.

The study was sponsored by Pfizer in collaboration with Merck KGaA, Germany. Dr. Chen has consulted and served in a speakers’ bureau for Seattle Genetics, Millennium, and Genentech. He has also received research funding from Pharmacyclics, Seattle Genetics, Millennium, and Merck.

Lugano, Switzerland – A combination of obinutuzumab (Gazyva) and the experimental immunomodulatory agent CC-122 showed “clinically meaningful” activity against relapsed/refractory diffuse large B cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1b study.

Among 38 patients with heavily pretreated, relapsed/refractory DLBCL, follicular lymphoma (FL), or marginal zone lymphoma (MZL), the overall response rate was 66%, including 12 patients (32%) with a complete response (CR), reported Jean-Marie Michot, MD, from the Goustave-Roussy Cancer Center in Villejuif, France.

hematologynews@frontlinemedcom.com

Lugano, Switzerland – A combination of obinutuzumab (Gazyva) and the experimental immunomodulatory agent CC-122 showed “clinically meaningful” activity against relapsed/refractory diffuse large B cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1b study.

Among 38 patients with heavily pretreated, relapsed/refractory DLBCL, follicular lymphoma (FL), or marginal zone lymphoma (MZL), the overall response rate was 66%, including 12 patients (32%) with a complete response (CR), reported Jean-Marie Michot, MD, from the Goustave-Roussy Cancer Center in Villejuif, France.

hematologynews@frontlinemedcom.com

Lugano, Switzerland – A combination of obinutuzumab (Gazyva) and the experimental immunomodulatory agent CC-122 showed “clinically meaningful” activity against relapsed/refractory diffuse large B cell lymphoma (DLBCL) and indolent non-Hodgkin lymphoma (NHL) in a phase 1b study.

Among 38 patients with heavily pretreated, relapsed/refractory DLBCL, follicular lymphoma (FL), or marginal zone lymphoma (MZL), the overall response rate was 66%, including 12 patients (32%) with a complete response (CR), reported Jean-Marie Michot, MD, from the Goustave-Roussy Cancer Center in Villejuif, France.

hematologynews@frontlinemedcom.com

LUGANO, SWITZERLAND – Copanlisib, an investigational intravenous inhibitor of phosphatidylinositol 3-kinase (PI3K), was associated with “promising” efficacy and a better safety profile than has been seen with oral PI3K inhibitors in patients with relapsed or refractory indolent lymphomas.

In a phase 2 trial of the drug as monotherapy in patients with indolent lymphomas, copanlisib was associated with an overall response rate of 58.6% among 104 patients with follicular lymphoma (FL), including 14.4% complete responses (CR) and 44.2% partial responses (PR), reported Martin Dreyling, MD, of the Universität München-Grosshadern in Munich, Germany.

“The favorable risk-benefit profile of this compound suggests further [need for] testing in follicular lymphoma. My personal interpretation is that the different safety profile is due to the intermittent dosing and the IV application, avoiding adverse cause-effect both in the gut and the liver,” he said at the 14th International Conference on Malignant Lymphoma.

Dr. Dreyling noted that the oral PI3K inhibitor idelalisib (Zydelig) is approved for the treatment of patients with relapsed chronic lymphocytic leukemia in combination with rituximab and in patients with relapsed FL or small lymphocytic lymphomas (SLL) who have received at least two prior lines of systemic therapy. This agent, however, carries a black box warning about fatal and serious toxicities, including hepatic events, severe diarrhea, colitis, pneumonitis, infections, and intestinal perforation.

Copanlisib inhibits all isoforms of P13K but is predominantly active against the alpha and delta isoforms of the kinase. The alpha form, expressed in many cell types, is involved in insulin signaling and angiogenesis and in resistance mechanisms to lymphoma. The delta form, expressed in leukocytes, is involved in B-cell signaling, development, and survival, making PIK3 an attractive target, Dr. Dreyling explained.

The study included patients with indolent B-cell lymphomas, including FL grades 1-3a, marginal zone lymphoma, SLL, or lymphoplasmacytic lymphoma/Waldenstrom macroglobulinemia (LPL/WM) for whom at least two prior lines of therapy had failed.

The patients received copanlisib 60 mg IV on days 1, 8, and 15 of each 28-day cycle until disease progression or unacceptable toxicity.

Of 142 assigned to and started on treatment, 46 patients (32.3%) remained on treatment at the time of data cutoff. Of the 96 patients (67.7%) who discontinued, 35 did so because of adverse events, 36 discontinued for radiologic or clinical evidence of progression, 16 withdrew, 5 were discontinued on the treating physician’s decision, and 4 stopped for other, unspecified reasons.

Among all 142 patients, the median duration of therapy was 22 weeks and the median number of cycles was 5.5. In all, 26.1% of patients required a dosage reduction to 45 mg, and 5.6% required reduction to 30 mg.

As noted, the objective tumor response rate (ORR) among patients was 58.6% for 104 patients with FL. For the 23 patients with marginal zone lymphoma, the ORR was 69.6%, consisting of two complete and 14 partial responses. Among eight patients with SLL, there were six partial responses and no complete responses. For the six patients with LPL/WM, there was one partial response.

The overall median duration of response was 22.6 months. Among patients with refractory disease and in all patients with FL the median duration of response was 12.2 months.

The median progression-free survival after 24 months of follow-up was 11.2 months for all patients. The median overall survival has not been reached.

The most frequent adverse events of grade 3 or 4 were hyperglycemia in 40.1% (33.1% grade 3 and 7.0% grade 4) and hypertension in 22.5% (all grade 3).

Grade 3 diarrhea, a significant problem with idelalisib, occurred in 4.2% of patients, and there were no grade 4 events.

Grade 3 pneumonitis was seen in two patients, and one had grade 4 colitis. There were three drug related deaths, including one patient each from lung infection, respiratory failure, or thromboembolic event..

The study was supported by Bayer. Dr. Dreyling disclosed receiving honoraria from the company and serving on a scientific/advisory board for the company.

LUGANO, SWITZERLAND – Copanlisib, an investigational intravenous inhibitor of phosphatidylinositol 3-kinase (PI3K), was associated with “promising” efficacy and a better safety profile than has been seen with oral PI3K inhibitors in patients with relapsed or refractory indolent lymphomas.

In a phase 2 trial of the drug as monotherapy in patients with indolent lymphomas, copanlisib was associated with an overall response rate of 58.6% among 104 patients with follicular lymphoma (FL), including 14.4% complete responses (CR) and 44.2% partial responses (PR), reported Martin Dreyling, MD, of the Universität München-Grosshadern in Munich, Germany.

“The favorable risk-benefit profile of this compound suggests further [need for] testing in follicular lymphoma. My personal interpretation is that the different safety profile is due to the intermittent dosing and the IV application, avoiding adverse cause-effect both in the gut and the liver,” he said at the 14th International Conference on Malignant Lymphoma.

Dr. Dreyling noted that the oral PI3K inhibitor idelalisib (Zydelig) is approved for the treatment of patients with relapsed chronic lymphocytic leukemia in combination with rituximab and in patients with relapsed FL or small lymphocytic lymphomas (SLL) who have received at least two prior lines of systemic therapy. This agent, however, carries a black box warning about fatal and serious toxicities, including hepatic events, severe diarrhea, colitis, pneumonitis, infections, and intestinal perforation.

Copanlisib inhibits all isoforms of P13K but is predominantly active against the alpha and delta isoforms of the kinase. The alpha form, expressed in many cell types, is involved in insulin signaling and angiogenesis and in resistance mechanisms to lymphoma. The delta form, expressed in leukocytes, is involved in B-cell signaling, development, and survival, making PIK3 an attractive target, Dr. Dreyling explained.

The study included patients with indolent B-cell lymphomas, including FL grades 1-3a, marginal zone lymphoma, SLL, or lymphoplasmacytic lymphoma/Waldenstrom macroglobulinemia (LPL/WM) for whom at least two prior lines of therapy had failed.

The patients received copanlisib 60 mg IV on days 1, 8, and 15 of each 28-day cycle until disease progression or unacceptable toxicity.

Of 142 assigned to and started on treatment, 46 patients (32.3%) remained on treatment at the time of data cutoff. Of the 96 patients (67.7%) who discontinued, 35 did so because of adverse events, 36 discontinued for radiologic or clinical evidence of progression, 16 withdrew, 5 were discontinued on the treating physician’s decision, and 4 stopped for other, unspecified reasons.

Among all 142 patients, the median duration of therapy was 22 weeks and the median number of cycles was 5.5. In all, 26.1% of patients required a dosage reduction to 45 mg, and 5.6% required reduction to 30 mg.

As noted, the objective tumor response rate (ORR) among patients was 58.6% for 104 patients with FL. For the 23 patients with marginal zone lymphoma, the ORR was 69.6%, consisting of two complete and 14 partial responses. Among eight patients with SLL, there were six partial responses and no complete responses. For the six patients with LPL/WM, there was one partial response.

The overall median duration of response was 22.6 months. Among patients with refractory disease and in all patients with FL the median duration of response was 12.2 months.

The median progression-free survival after 24 months of follow-up was 11.2 months for all patients. The median overall survival has not been reached.

The most frequent adverse events of grade 3 or 4 were hyperglycemia in 40.1% (33.1% grade 3 and 7.0% grade 4) and hypertension in 22.5% (all grade 3).

Grade 3 diarrhea, a significant problem with idelalisib, occurred in 4.2% of patients, and there were no grade 4 events.

Grade 3 pneumonitis was seen in two patients, and one had grade 4 colitis. There were three drug related deaths, including one patient each from lung infection, respiratory failure, or thromboembolic event..

The study was supported by Bayer. Dr. Dreyling disclosed receiving honoraria from the company and serving on a scientific/advisory board for the company.

LUGANO, SWITZERLAND – Copanlisib, an investigational intravenous inhibitor of phosphatidylinositol 3-kinase (PI3K), was associated with “promising” efficacy and a better safety profile than has been seen with oral PI3K inhibitors in patients with relapsed or refractory indolent lymphomas.

In a phase 2 trial of the drug as monotherapy in patients with indolent lymphomas, copanlisib was associated with an overall response rate of 58.6% among 104 patients with follicular lymphoma (FL), including 14.4% complete responses (CR) and 44.2% partial responses (PR), reported Martin Dreyling, MD, of the Universität München-Grosshadern in Munich, Germany.

“The favorable risk-benefit profile of this compound suggests further [need for] testing in follicular lymphoma. My personal interpretation is that the different safety profile is due to the intermittent dosing and the IV application, avoiding adverse cause-effect both in the gut and the liver,” he said at the 14th International Conference on Malignant Lymphoma.

Dr. Dreyling noted that the oral PI3K inhibitor idelalisib (Zydelig) is approved for the treatment of patients with relapsed chronic lymphocytic leukemia in combination with rituximab and in patients with relapsed FL or small lymphocytic lymphomas (SLL) who have received at least two prior lines of systemic therapy. This agent, however, carries a black box warning about fatal and serious toxicities, including hepatic events, severe diarrhea, colitis, pneumonitis, infections, and intestinal perforation.

Copanlisib inhibits all isoforms of P13K but is predominantly active against the alpha and delta isoforms of the kinase. The alpha form, expressed in many cell types, is involved in insulin signaling and angiogenesis and in resistance mechanisms to lymphoma. The delta form, expressed in leukocytes, is involved in B-cell signaling, development, and survival, making PIK3 an attractive target, Dr. Dreyling explained.

The study included patients with indolent B-cell lymphomas, including FL grades 1-3a, marginal zone lymphoma, SLL, or lymphoplasmacytic lymphoma/Waldenstrom macroglobulinemia (LPL/WM) for whom at least two prior lines of therapy had failed.

The patients received copanlisib 60 mg IV on days 1, 8, and 15 of each 28-day cycle until disease progression or unacceptable toxicity.

Of 142 assigned to and started on treatment, 46 patients (32.3%) remained on treatment at the time of data cutoff. Of the 96 patients (67.7%) who discontinued, 35 did so because of adverse events, 36 discontinued for radiologic or clinical evidence of progression, 16 withdrew, 5 were discontinued on the treating physician’s decision, and 4 stopped for other, unspecified reasons.

Among all 142 patients, the median duration of therapy was 22 weeks and the median number of cycles was 5.5. In all, 26.1% of patients required a dosage reduction to 45 mg, and 5.6% required reduction to 30 mg.

As noted, the objective tumor response rate (ORR) among patients was 58.6% for 104 patients with FL. For the 23 patients with marginal zone lymphoma, the ORR was 69.6%, consisting of two complete and 14 partial responses. Among eight patients with SLL, there were six partial responses and no complete responses. For the six patients with LPL/WM, there was one partial response.

The overall median duration of response was 22.6 months. Among patients with refractory disease and in all patients with FL the median duration of response was 12.2 months.

The median progression-free survival after 24 months of follow-up was 11.2 months for all patients. The median overall survival has not been reached.

The most frequent adverse events of grade 3 or 4 were hyperglycemia in 40.1% (33.1% grade 3 and 7.0% grade 4) and hypertension in 22.5% (all grade 3).

Grade 3 diarrhea, a significant problem with idelalisib, occurred in 4.2% of patients, and there were no grade 4 events.

Grade 3 pneumonitis was seen in two patients, and one had grade 4 colitis. There were three drug related deaths, including one patient each from lung infection, respiratory failure, or thromboembolic event..

The study was supported by Bayer. Dr. Dreyling disclosed receiving honoraria from the company and serving on a scientific/advisory board for the company.

LUGANO, SWITZERLAND – Tazemetostat, a first-in-class experimental agent that inhibits an oncogenic protein, shows efficacy in patients with heavily pretreated, relapsed/refractory follicular lymphoma (FL) and diffuse large B cell lymphoma (DLBCL), interim results from a phase II study suggest.

Among patients with relapsed/refractory FL who had mutations in EZH2 (enhancer of zeste homolog 2), a member of a family of proteins that are involved in epigenetic gene silencing, the overall response rate (ORR) was 92%, reported Franck Morschhauser, MD, PhD, of the University of Lille, France.

Neil Osterweil/Frontline Medical News

Large multicenter study

Dr. Morschhauser reported interim results from a global, multi-center open-label study of tazemetostat in six cohorts of patients with relapsed/refractory FL (two monotherapy cohorts of 45 patients each) or DLBCL (three monotherapy cohorts of 60 patients each). A sixth cohort consisting of 70 patients with DLBCL treated with tazemetostat and prednisolone was added in 2017.

In the ongoing trial, patients receive oral tazemetostat 800 mg twice daily until disease progression or withdrawal from study, and are being followed for ORR, progression-free survival, overall survival, duration-of response, safety, and pharmacokinetics.

The longest follow-up at the time of data cutoff was approximately 18 months. Among 13 evaluable patients with FL with EZH2 mutations, the ORR was 92%, including one complete response (CR) and 11 partial responses (PR). In contrast, the ORR for 54 patients with FL and wild-type EZH2 was 28%, consisting of three CRs and 11 PRs. One patient with mutated EZH2 and 23 with wild-type EZH2 had stable disease.

Among 17 patients with DLBCL and EZH2 mutations, the ORR was 29%, consisting of 5 PR. For 119 patients with wild-type EZH2, the ORR was 15%, consisting of 10 CR and 8 PR. Six patients with mutations and 22 with wild-type EZH2 had stable disease.

Among the patients with FL, 75% had significant reduction in tumor burden.

The time to response ranged from 2 months to 1 year, with a median of approximately 4 months.

The variability in time to response “makes it a little bit tricky to calculate response duration,” Dr. Morschhauser said.

The drug had a “favorable” safety profile, with treatment-related adverse events of grade 3 or greater in more than 5% of patients including thrombocytopenias in 6% of patients, anemias in 4%, and neutropenias in 6%. Treatment-emergent adverse events leading to dose reductions occurred in 4% of patients, and those leading to drug discontinuation or study withdrawal occurred in 12% of patients.

In a retrospective analysis, the investigators performed molecular profiling studies using next-generation sequencing to look for predictors of response to tazemetostat. They found that patients most likely to respond to tazemetostat were those with activating mutations in EZH2 and MYD88. In contrast, patients with mutations HIST1H1E or MYC were not likely to respond.

Thomas E. Witzig, MD, of the Mayo Clinic in Rochester, Minn., the invited discussant, said that the study is important because “it provides proof of principle that attacking the methylation issue, attacking one of these enzymes, is very important and can produce single-agent responses.

“It also demonstrates the value of mutation status, and this trial knowledge of that mutation status has actually changed the trial design, so that now they are only putting patients on with mutations,” he said.

The trial also raises the possibility of targeting other parts of the methylation pathway to treat cancer, he added.

The study was sponsored by Epizyme, the maker of tazemetostat. Dr. Morschhauser disclosed receiving honoraria from and serving on advisory boards for both companies. Dr. Witzig has disclosed grants for clinical trials from Novartis and Wyeth, and he has served on advisory boards for Cephalon, Novartis, and Wyeth.

LUGANO, SWITZERLAND – Tazemetostat, a first-in-class experimental agent that inhibits an oncogenic protein, shows efficacy in patients with heavily pretreated, relapsed/refractory follicular lymphoma (FL) and diffuse large B cell lymphoma (DLBCL), interim results from a phase II study suggest.

Among patients with relapsed/refractory FL who had mutations in EZH2 (enhancer of zeste homolog 2), a member of a family of proteins that are involved in epigenetic gene silencing, the overall response rate (ORR) was 92%, reported Franck Morschhauser, MD, PhD, of the University of Lille, France.

Neil Osterweil/Frontline Medical News

Large multicenter study

Dr. Morschhauser reported interim results from a global, multi-center open-label study of tazemetostat in six cohorts of patients with relapsed/refractory FL (two monotherapy cohorts of 45 patients each) or DLBCL (three monotherapy cohorts of 60 patients each). A sixth cohort consisting of 70 patients with DLBCL treated with tazemetostat and prednisolone was added in 2017.

In the ongoing trial, patients receive oral tazemetostat 800 mg twice daily until disease progression or withdrawal from study, and are being followed for ORR, progression-free survival, overall survival, duration-of response, safety, and pharmacokinetics.

The longest follow-up at the time of data cutoff was approximately 18 months. Among 13 evaluable patients with FL with EZH2 mutations, the ORR was 92%, including one complete response (CR) and 11 partial responses (PR). In contrast, the ORR for 54 patients with FL and wild-type EZH2 was 28%, consisting of three CRs and 11 PRs. One patient with mutated EZH2 and 23 with wild-type EZH2 had stable disease.

Among 17 patients with DLBCL and EZH2 mutations, the ORR was 29%, consisting of 5 PR. For 119 patients with wild-type EZH2, the ORR was 15%, consisting of 10 CR and 8 PR. Six patients with mutations and 22 with wild-type EZH2 had stable disease.

Among the patients with FL, 75% had significant reduction in tumor burden.

The time to response ranged from 2 months to 1 year, with a median of approximately 4 months.

The variability in time to response “makes it a little bit tricky to calculate response duration,” Dr. Morschhauser said.

The drug had a “favorable” safety profile, with treatment-related adverse events of grade 3 or greater in more than 5% of patients including thrombocytopenias in 6% of patients, anemias in 4%, and neutropenias in 6%. Treatment-emergent adverse events leading to dose reductions occurred in 4% of patients, and those leading to drug discontinuation or study withdrawal occurred in 12% of patients.

In a retrospective analysis, the investigators performed molecular profiling studies using next-generation sequencing to look for predictors of response to tazemetostat. They found that patients most likely to respond to tazemetostat were those with activating mutations in EZH2 and MYD88. In contrast, patients with mutations HIST1H1E or MYC were not likely to respond.

Thomas E. Witzig, MD, of the Mayo Clinic in Rochester, Minn., the invited discussant, said that the study is important because “it provides proof of principle that attacking the methylation issue, attacking one of these enzymes, is very important and can produce single-agent responses.

“It also demonstrates the value of mutation status, and this trial knowledge of that mutation status has actually changed the trial design, so that now they are only putting patients on with mutations,” he said.

The trial also raises the possibility of targeting other parts of the methylation pathway to treat cancer, he added.

The study was sponsored by Epizyme, the maker of tazemetostat. Dr. Morschhauser disclosed receiving honoraria from and serving on advisory boards for both companies. Dr. Witzig has disclosed grants for clinical trials from Novartis and Wyeth, and he has served on advisory boards for Cephalon, Novartis, and Wyeth.

LUGANO, SWITZERLAND – Tazemetostat, a first-in-class experimental agent that inhibits an oncogenic protein, shows efficacy in patients with heavily pretreated, relapsed/refractory follicular lymphoma (FL) and diffuse large B cell lymphoma (DLBCL), interim results from a phase II study suggest.

Among patients with relapsed/refractory FL who had mutations in EZH2 (enhancer of zeste homolog 2), a member of a family of proteins that are involved in epigenetic gene silencing, the overall response rate (ORR) was 92%, reported Franck Morschhauser, MD, PhD, of the University of Lille, France.

Neil Osterweil/Frontline Medical News

Large multicenter study

Dr. Morschhauser reported interim results from a global, multi-center open-label study of tazemetostat in six cohorts of patients with relapsed/refractory FL (two monotherapy cohorts of 45 patients each) or DLBCL (three monotherapy cohorts of 60 patients each). A sixth cohort consisting of 70 patients with DLBCL treated with tazemetostat and prednisolone was added in 2017.

In the ongoing trial, patients receive oral tazemetostat 800 mg twice daily until disease progression or withdrawal from study, and are being followed for ORR, progression-free survival, overall survival, duration-of response, safety, and pharmacokinetics.

The longest follow-up at the time of data cutoff was approximately 18 months. Among 13 evaluable patients with FL with EZH2 mutations, the ORR was 92%, including one complete response (CR) and 11 partial responses (PR). In contrast, the ORR for 54 patients with FL and wild-type EZH2 was 28%, consisting of three CRs and 11 PRs. One patient with mutated EZH2 and 23 with wild-type EZH2 had stable disease.

Among 17 patients with DLBCL and EZH2 mutations, the ORR was 29%, consisting of 5 PR. For 119 patients with wild-type EZH2, the ORR was 15%, consisting of 10 CR and 8 PR. Six patients with mutations and 22 with wild-type EZH2 had stable disease.

Among the patients with FL, 75% had significant reduction in tumor burden.

The time to response ranged from 2 months to 1 year, with a median of approximately 4 months.

The variability in time to response “makes it a little bit tricky to calculate response duration,” Dr. Morschhauser said.

The drug had a “favorable” safety profile, with treatment-related adverse events of grade 3 or greater in more than 5% of patients including thrombocytopenias in 6% of patients, anemias in 4%, and neutropenias in 6%. Treatment-emergent adverse events leading to dose reductions occurred in 4% of patients, and those leading to drug discontinuation or study withdrawal occurred in 12% of patients.

In a retrospective analysis, the investigators performed molecular profiling studies using next-generation sequencing to look for predictors of response to tazemetostat. They found that patients most likely to respond to tazemetostat were those with activating mutations in EZH2 and MYD88. In contrast, patients with mutations HIST1H1E or MYC were not likely to respond.

Thomas E. Witzig, MD, of the Mayo Clinic in Rochester, Minn., the invited discussant, said that the study is important because “it provides proof of principle that attacking the methylation issue, attacking one of these enzymes, is very important and can produce single-agent responses.

“It also demonstrates the value of mutation status, and this trial knowledge of that mutation status has actually changed the trial design, so that now they are only putting patients on with mutations,” he said.

The trial also raises the possibility of targeting other parts of the methylation pathway to treat cancer, he added.

The study was sponsored by Epizyme, the maker of tazemetostat. Dr. Morschhauser disclosed receiving honoraria from and serving on advisory boards for both companies. Dr. Witzig has disclosed grants for clinical trials from Novartis and Wyeth, and he has served on advisory boards for Cephalon, Novartis, and Wyeth.

LUGANO, SWITZERLAND – A combination of the Bruton’s tyrosine kinase (BTK) ibrutinib (Imbruvica) and the pan-phosphoinositide 3-kinase (PI3K) inhibitor buparlisib showed clinical activity superior to that of single-agent ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL).

In a phase I/IB dose escalation study and expansion cohort testing the combination in patients with diffuse large B cell lymphoma (DLBCL), follicular lymphoma, and MCL, the overall response rate (ORR) among patients with MCL was 100%, consisting of complete responses (CR) in 8 of 11 patients, and partial responses (PR) in 3 patients, reported Connie Lee Batlevi, MD, of Memorial Sloan Kettering Cancer Center in New York.

LUGANO, SWITZERLAND – A combination of the Bruton’s tyrosine kinase (BTK) ibrutinib (Imbruvica) and the pan-phosphoinositide 3-kinase (PI3K) inhibitor buparlisib showed clinical activity superior to that of single-agent ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL).

In a phase I/IB dose escalation study and expansion cohort testing the combination in patients with diffuse large B cell lymphoma (DLBCL), follicular lymphoma, and MCL, the overall response rate (ORR) among patients with MCL was 100%, consisting of complete responses (CR) in 8 of 11 patients, and partial responses (PR) in 3 patients, reported Connie Lee Batlevi, MD, of Memorial Sloan Kettering Cancer Center in New York.

LUGANO, SWITZERLAND – A combination of the Bruton’s tyrosine kinase (BTK) ibrutinib (Imbruvica) and the pan-phosphoinositide 3-kinase (PI3K) inhibitor buparlisib showed clinical activity superior to that of single-agent ibrutinib in patients with relapsed/refractory mantle cell lymphoma (MCL).

In a phase I/IB dose escalation study and expansion cohort testing the combination in patients with diffuse large B cell lymphoma (DLBCL), follicular lymphoma, and MCL, the overall response rate (ORR) among patients with MCL was 100%, consisting of complete responses (CR) in 8 of 11 patients, and partial responses (PR) in 3 patients, reported Connie Lee Batlevi, MD, of Memorial Sloan Kettering Cancer Center in New York.

LUGANO, SWITZERLAND – A novel combination of the anti-programmed death 1 (PD-1) checkpoint inhibitor pembrolizumab (Keytruda) and the anti-CD20 monoclonal antibody rituximab was associated with a high overall response rate (ORR) in patients with relapsed follicular lymphoma in a phase II clinical trial.

Among 20 patients evaluable for efficacy, the overall response rate to the combination was 65%, including 50% complete responses (CR) reported Loretta J. Nastoupil, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“Follicular lymphoma is probably one of the best examples of targeting the immune system and also one of the earliest examples. Over the last few years we’ve learned a great deal about the different mechanisms of not only negative impact on infiltrating T cells, but also immune escape and T-cell exhaustion,” she said at the International Conference on Malignant Lymphoma.

Although biopsies of follicular lymphoma tumors have demonstrated infiltration of anti-tumor T cells, these cells are typically impeded by immune checkpoints, including PD-1 and its ligand (PD-L1).

The use of anti-PD-1 checkpoint inhibitors such as pembrolizumab has been shown to enhance the function of antitumor T cells in follicular lymphoma, and blocking PD-1 on natural killer cells enhances the antibody-dependent cell-mediated cytotoxicity of the natural killer cells, she said.

Because rituximab, a mainstay of therapy for non-Hodgkin lymphomas, induces antibody-dependent cell-mediated cytotoxicity, the investigators reasoned that combining it with pembrolizumab would simultaneously and synergistically stimulate activation of innate and adaptive immunity.

They designed a phase II, single-arm study in 30 patients with relapsed follicular lymphoma following one or more prior lines of therapy. The patients also had to have rituximab-sensitive disease, defined as a complete response (CR) or partial response lasting for at least 6 months following the most recent rituximab-containing therapy.

The patients were treated with rituximab 375 mg/m² IV on days 1, 8, 15, and 22 of cycle 1, and pembrolizumab 200 mg IV every 3 weeks for up to 16 cycles starting on day 2 of cycle 1.

The investigators expected that the combination would improve ORR, the primary endpoint, to at least 60%, compared with 40% for historical controls treated with repeat courses of rituximab.

At the data cutoff for the interim analysis, 32 patients had been enrolled, 30 were evaluable for safety, and 20 for efficacy after a median follow-up of 8.2 months.

Among the 20 patients (median age 64) in the efficacy analysis, 10 (50%) had a CR, and 3 (15%) had a partial response, for an ORR of 65%. Three additional patients had stable disease, and four had disease progression as best responses.

Among the patients with CRs, the duration of response ranged from nearly 275 days to more than 600 days.

“This does appear to be durable, and it is time dependent in terms of response. We did see early response, and we also saw deepening of response over time,” Dr. Nastoupil said.

Four patients were discontinued from the study because of immune-related adverse events. All four patients had achieved a CR at the time of study removal, and all four have ongoing CRs.

Among the 30 patients evaluable for safety, there were no grade 4 adverse events, no deaths, and few grade 3 events. Most events were grade 1 or 2, and included fatigue, eye pain/blurred vision/watery eye, nausea and vomiting, diarrhea dyspnea, rash, cough, and lymphopenia.

The investigators also looked at potential biomarkers for response, including PD-L1 expression in tumors prior to treatment. They found in samples from three patients who went on to achieve CRs that PD-L1 expression in tumor cells was low, ranging from 0% to 8%, suggesting that PD-L1 expression may not be necessary to generate a response with the combination.

They then looked at the association between CD8-positive T effector cells and responses in 12 patients, and found that patients with higher levels of expression had better ORR and CR rates.

“These interim results warrant further investigation of this combination in follicular lymphoma, and an expansion to include patients with refractory follicular lymphoma is planned,” Dr. Nastoupil concluded.

The Leukemia & Lymphoma Society supported the study. Dr Nastoupil has disclosed consulting fees from Celgene and contracted research for Abbvie, Janssen, and TG Therapeutics.

LUGANO, SWITZERLAND – A novel combination of the anti-programmed death 1 (PD-1) checkpoint inhibitor pembrolizumab (Keytruda) and the anti-CD20 monoclonal antibody rituximab was associated with a high overall response rate (ORR) in patients with relapsed follicular lymphoma in a phase II clinical trial.

Among 20 patients evaluable for efficacy, the overall response rate to the combination was 65%, including 50% complete responses (CR) reported Loretta J. Nastoupil, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“Follicular lymphoma is probably one of the best examples of targeting the immune system and also one of the earliest examples. Over the last few years we’ve learned a great deal about the different mechanisms of not only negative impact on infiltrating T cells, but also immune escape and T-cell exhaustion,” she said at the International Conference on Malignant Lymphoma.

Although biopsies of follicular lymphoma tumors have demonstrated infiltration of anti-tumor T cells, these cells are typically impeded by immune checkpoints, including PD-1 and its ligand (PD-L1).

The use of anti-PD-1 checkpoint inhibitors such as pembrolizumab has been shown to enhance the function of antitumor T cells in follicular lymphoma, and blocking PD-1 on natural killer cells enhances the antibody-dependent cell-mediated cytotoxicity of the natural killer cells, she said.

Because rituximab, a mainstay of therapy for non-Hodgkin lymphomas, induces antibody-dependent cell-mediated cytotoxicity, the investigators reasoned that combining it with pembrolizumab would simultaneously and synergistically stimulate activation of innate and adaptive immunity.

They designed a phase II, single-arm study in 30 patients with relapsed follicular lymphoma following one or more prior lines of therapy. The patients also had to have rituximab-sensitive disease, defined as a complete response (CR) or partial response lasting for at least 6 months following the most recent rituximab-containing therapy.

The patients were treated with rituximab 375 mg/m² IV on days 1, 8, 15, and 22 of cycle 1, and pembrolizumab 200 mg IV every 3 weeks for up to 16 cycles starting on day 2 of cycle 1.

The investigators expected that the combination would improve ORR, the primary endpoint, to at least 60%, compared with 40% for historical controls treated with repeat courses of rituximab.

At the data cutoff for the interim analysis, 32 patients had been enrolled, 30 were evaluable for safety, and 20 for efficacy after a median follow-up of 8.2 months.

Among the 20 patients (median age 64) in the efficacy analysis, 10 (50%) had a CR, and 3 (15%) had a partial response, for an ORR of 65%. Three additional patients had stable disease, and four had disease progression as best responses.

Among the patients with CRs, the duration of response ranged from nearly 275 days to more than 600 days.

“This does appear to be durable, and it is time dependent in terms of response. We did see early response, and we also saw deepening of response over time,” Dr. Nastoupil said.

Four patients were discontinued from the study because of immune-related adverse events. All four patients had achieved a CR at the time of study removal, and all four have ongoing CRs.

Among the 30 patients evaluable for safety, there were no grade 4 adverse events, no deaths, and few grade 3 events. Most events were grade 1 or 2, and included fatigue, eye pain/blurred vision/watery eye, nausea and vomiting, diarrhea dyspnea, rash, cough, and lymphopenia.

The investigators also looked at potential biomarkers for response, including PD-L1 expression in tumors prior to treatment. They found in samples from three patients who went on to achieve CRs that PD-L1 expression in tumor cells was low, ranging from 0% to 8%, suggesting that PD-L1 expression may not be necessary to generate a response with the combination.

They then looked at the association between CD8-positive T effector cells and responses in 12 patients, and found that patients with higher levels of expression had better ORR and CR rates.

“These interim results warrant further investigation of this combination in follicular lymphoma, and an expansion to include patients with refractory follicular lymphoma is planned,” Dr. Nastoupil concluded.

The Leukemia & Lymphoma Society supported the study. Dr Nastoupil has disclosed consulting fees from Celgene and contracted research for Abbvie, Janssen, and TG Therapeutics.

LUGANO, SWITZERLAND – A novel combination of the anti-programmed death 1 (PD-1) checkpoint inhibitor pembrolizumab (Keytruda) and the anti-CD20 monoclonal antibody rituximab was associated with a high overall response rate (ORR) in patients with relapsed follicular lymphoma in a phase II clinical trial.

Among 20 patients evaluable for efficacy, the overall response rate to the combination was 65%, including 50% complete responses (CR) reported Loretta J. Nastoupil, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“Follicular lymphoma is probably one of the best examples of targeting the immune system and also one of the earliest examples. Over the last few years we’ve learned a great deal about the different mechanisms of not only negative impact on infiltrating T cells, but also immune escape and T-cell exhaustion,” she said at the International Conference on Malignant Lymphoma.

Although biopsies of follicular lymphoma tumors have demonstrated infiltration of anti-tumor T cells, these cells are typically impeded by immune checkpoints, including PD-1 and its ligand (PD-L1).

The use of anti-PD-1 checkpoint inhibitors such as pembrolizumab has been shown to enhance the function of antitumor T cells in follicular lymphoma, and blocking PD-1 on natural killer cells enhances the antibody-dependent cell-mediated cytotoxicity of the natural killer cells, she said.

Because rituximab, a mainstay of therapy for non-Hodgkin lymphomas, induces antibody-dependent cell-mediated cytotoxicity, the investigators reasoned that combining it with pembrolizumab would simultaneously and synergistically stimulate activation of innate and adaptive immunity.

They designed a phase II, single-arm study in 30 patients with relapsed follicular lymphoma following one or more prior lines of therapy. The patients also had to have rituximab-sensitive disease, defined as a complete response (CR) or partial response lasting for at least 6 months following the most recent rituximab-containing therapy.

The patients were treated with rituximab 375 mg/m² IV on days 1, 8, 15, and 22 of cycle 1, and pembrolizumab 200 mg IV every 3 weeks for up to 16 cycles starting on day 2 of cycle 1.

The investigators expected that the combination would improve ORR, the primary endpoint, to at least 60%, compared with 40% for historical controls treated with repeat courses of rituximab.

At the data cutoff for the interim analysis, 32 patients had been enrolled, 30 were evaluable for safety, and 20 for efficacy after a median follow-up of 8.2 months.

Among the 20 patients (median age 64) in the efficacy analysis, 10 (50%) had a CR, and 3 (15%) had a partial response, for an ORR of 65%. Three additional patients had stable disease, and four had disease progression as best responses.

Among the patients with CRs, the duration of response ranged from nearly 275 days to more than 600 days.

“This does appear to be durable, and it is time dependent in terms of response. We did see early response, and we also saw deepening of response over time,” Dr. Nastoupil said.

Four patients were discontinued from the study because of immune-related adverse events. All four patients had achieved a CR at the time of study removal, and all four have ongoing CRs.

Among the 30 patients evaluable for safety, there were no grade 4 adverse events, no deaths, and few grade 3 events. Most events were grade 1 or 2, and included fatigue, eye pain/blurred vision/watery eye, nausea and vomiting, diarrhea dyspnea, rash, cough, and lymphopenia.

The investigators also looked at potential biomarkers for response, including PD-L1 expression in tumors prior to treatment. They found in samples from three patients who went on to achieve CRs that PD-L1 expression in tumor cells was low, ranging from 0% to 8%, suggesting that PD-L1 expression may not be necessary to generate a response with the combination.

They then looked at the association between CD8-positive T effector cells and responses in 12 patients, and found that patients with higher levels of expression had better ORR and CR rates.

“These interim results warrant further investigation of this combination in follicular lymphoma, and an expansion to include patients with refractory follicular lymphoma is planned,” Dr. Nastoupil concluded.

The Leukemia & Lymphoma Society supported the study. Dr Nastoupil has disclosed consulting fees from Celgene and contracted research for Abbvie, Janssen, and TG Therapeutics.

Lugano, Switzerland – It’s not the end of chemotherapy for young patients with newly diagnosed mantle cell lymphoma (MCL), but it’s a start.

For these patients, induction with a combination of ibrutinib and rituximab, followed by shorter cycles of chemoimmunotherapy, was associated in an early study with an objective response rate of 100%, including 90% complete responses (CR), reported Michael Wang, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“This is the first time for a chemo-free therapy – ibrutinib/rituximab – to achieve an overall response rate of 100%. This has an unprecedented efficacy in the frontline in young patients with mantle-cell lymphoma,” he said at the 14th International Congress on Malignant Lymphoma.

In patients with relapsed or refractory MCL, the combination of ibrutinib and rituximab has been associated with durable responses in 88% of patients. The success of the combination suggests that fit patients younger than age 65 years with newly diagnosed MCL might benefit from a chemotherapy-free induction regimen with ibrutinib and rituximab, followed by consolidation with a short but intense course of chemoimmunotherapy, Dr. Wang said.

He presented updated results from the phase II Window I study, first results of which were reported at the 2016 meeting of the American Society of Hematology.

“Frontline therapy is the most important therapy for mantle cell lymphoma, because mantle cell lymphoma cells are most vulnerable to frontline attack. If the frontline therapy is good enough, it could kill all the mantle cell lymphoma cells, therefore leaving no chance for secondary resistance, and thereby (resulting in) long-term survival. And it is really my belief that if we ideally optimized the frontline therapy, that would be a shortcut to a cure,” he said.

To test this idea, Dr. Wang and MD Anderson colleagues initiated a phase II trial at their institution with 50 patients age 65 years or under with newly diagnosed, CD20-positive and Cyclin D1-positive MCL.

A total of 50 patients age 65 years or younger (median age 54) with newly diagnosed, untreated MCL underwent induction with continuous daily ibrutinib 560 mg, plus rituximab 375 mg/m² administered weekly for 4 weeks during cycle 1 and on day 1 of cycles 3-12. Consolidation consisted of rituximab plus hyper-CVAD (hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), alternating every 28 days with rituximab plus high-dose methotrexate–cytarabine.

Patients who had complete responses to induction received four cycles of chemoimmunotherapy, while those who experienced disease progression and those who had partial responses received chemoimmunotherapy for two cycles beyond the point of complete remissions.

At the time of the presentation, all 50 patients were evaluable for the induction phase (part 2), and 47 were evaluable for both induction and consolidation (part 2) .Of the evaluable patients, the overall response rate (ORR) to chemotherapy-free induction therapy alone (Part 1 ) was 100% (50), with CR in 90% of patients and partial responses (PR) in 10%. Of the 47 patients evaluable for part 2 (chemoimmunotherapy), all had CRs, for an ORR of 100%.

Dr. Wang noted that one patient had a dramatic radiographic reduction in spleen size following just two cycles of chemotherapy-free induction, and two other patients had similar reductions after four and six cycles, respectively.

After a median follow-up of 15.9 months, neither the median duration of response, progression-free survival, nor overall survival have been reached. There have been no deaths and only one case of disease progression after one year of therapy.

The patients generally tolerated the regimen very well, Dr. Wang said. There were no cases of lymphocytosis, bleeding, or atrial fibrillation after 332 combined cycles.

Nonhematological adverse events were primarily grade 1 or 2. Grade 3 fatigue was reported in approximately 10% of patients. There were no grade 4 adverse events.

“This study may provide a window of opportunity to reduce the frontline therapies and reduce the long-term toxicities such as secondary malignancies.” Dr. Wang said.

He acknowledged that four cycles of intensive chemotherapy is still toxic and that further efforts to reduce these toxicities are needed. The investigators are currently planning the Window II study, in which a fraction of patients will be treated with no chemotherapy at all, he said.­­­­

The study was supported by Pharmacyclics and Janssen. Dr. Wang disclosed receiving research grants and honoraria and serving as a consultant for the companies.

Lugano, Switzerland – It’s not the end of chemotherapy for young patients with newly diagnosed mantle cell lymphoma (MCL), but it’s a start.

For these patients, induction with a combination of ibrutinib and rituximab, followed by shorter cycles of chemoimmunotherapy, was associated in an early study with an objective response rate of 100%, including 90% complete responses (CR), reported Michael Wang, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“This is the first time for a chemo-free therapy – ibrutinib/rituximab – to achieve an overall response rate of 100%. This has an unprecedented efficacy in the frontline in young patients with mantle-cell lymphoma,” he said at the 14th International Congress on Malignant Lymphoma.

In patients with relapsed or refractory MCL, the combination of ibrutinib and rituximab has been associated with durable responses in 88% of patients. The success of the combination suggests that fit patients younger than age 65 years with newly diagnosed MCL might benefit from a chemotherapy-free induction regimen with ibrutinib and rituximab, followed by consolidation with a short but intense course of chemoimmunotherapy, Dr. Wang said.

He presented updated results from the phase II Window I study, first results of which were reported at the 2016 meeting of the American Society of Hematology.

“Frontline therapy is the most important therapy for mantle cell lymphoma, because mantle cell lymphoma cells are most vulnerable to frontline attack. If the frontline therapy is good enough, it could kill all the mantle cell lymphoma cells, therefore leaving no chance for secondary resistance, and thereby (resulting in) long-term survival. And it is really my belief that if we ideally optimized the frontline therapy, that would be a shortcut to a cure,” he said.

To test this idea, Dr. Wang and MD Anderson colleagues initiated a phase II trial at their institution with 50 patients age 65 years or under with newly diagnosed, CD20-positive and Cyclin D1-positive MCL.

A total of 50 patients age 65 years or younger (median age 54) with newly diagnosed, untreated MCL underwent induction with continuous daily ibrutinib 560 mg, plus rituximab 375 mg/m² administered weekly for 4 weeks during cycle 1 and on day 1 of cycles 3-12. Consolidation consisted of rituximab plus hyper-CVAD (hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), alternating every 28 days with rituximab plus high-dose methotrexate–cytarabine.

Patients who had complete responses to induction received four cycles of chemoimmunotherapy, while those who experienced disease progression and those who had partial responses received chemoimmunotherapy for two cycles beyond the point of complete remissions.

At the time of the presentation, all 50 patients were evaluable for the induction phase (part 2), and 47 were evaluable for both induction and consolidation (part 2) .Of the evaluable patients, the overall response rate (ORR) to chemotherapy-free induction therapy alone (Part 1 ) was 100% (50), with CR in 90% of patients and partial responses (PR) in 10%. Of the 47 patients evaluable for part 2 (chemoimmunotherapy), all had CRs, for an ORR of 100%.

Dr. Wang noted that one patient had a dramatic radiographic reduction in spleen size following just two cycles of chemotherapy-free induction, and two other patients had similar reductions after four and six cycles, respectively.

After a median follow-up of 15.9 months, neither the median duration of response, progression-free survival, nor overall survival have been reached. There have been no deaths and only one case of disease progression after one year of therapy.

The patients generally tolerated the regimen very well, Dr. Wang said. There were no cases of lymphocytosis, bleeding, or atrial fibrillation after 332 combined cycles.

Nonhematological adverse events were primarily grade 1 or 2. Grade 3 fatigue was reported in approximately 10% of patients. There were no grade 4 adverse events.

“This study may provide a window of opportunity to reduce the frontline therapies and reduce the long-term toxicities such as secondary malignancies.” Dr. Wang said.

He acknowledged that four cycles of intensive chemotherapy is still toxic and that further efforts to reduce these toxicities are needed. The investigators are currently planning the Window II study, in which a fraction of patients will be treated with no chemotherapy at all, he said.­­­­

The study was supported by Pharmacyclics and Janssen. Dr. Wang disclosed receiving research grants and honoraria and serving as a consultant for the companies.

Lugano, Switzerland – It’s not the end of chemotherapy for young patients with newly diagnosed mantle cell lymphoma (MCL), but it’s a start.

For these patients, induction with a combination of ibrutinib and rituximab, followed by shorter cycles of chemoimmunotherapy, was associated in an early study with an objective response rate of 100%, including 90% complete responses (CR), reported Michael Wang, MD, of the University of Texas MD Anderson Cancer Center in Houston.

“This is the first time for a chemo-free therapy – ibrutinib/rituximab – to achieve an overall response rate of 100%. This has an unprecedented efficacy in the frontline in young patients with mantle-cell lymphoma,” he said at the 14th International Congress on Malignant Lymphoma.

In patients with relapsed or refractory MCL, the combination of ibrutinib and rituximab has been associated with durable responses in 88% of patients. The success of the combination suggests that fit patients younger than age 65 years with newly diagnosed MCL might benefit from a chemotherapy-free induction regimen with ibrutinib and rituximab, followed by consolidation with a short but intense course of chemoimmunotherapy, Dr. Wang said.

He presented updated results from the phase II Window I study, first results of which were reported at the 2016 meeting of the American Society of Hematology.

“Frontline therapy is the most important therapy for mantle cell lymphoma, because mantle cell lymphoma cells are most vulnerable to frontline attack. If the frontline therapy is good enough, it could kill all the mantle cell lymphoma cells, therefore leaving no chance for secondary resistance, and thereby (resulting in) long-term survival. And it is really my belief that if we ideally optimized the frontline therapy, that would be a shortcut to a cure,” he said.

To test this idea, Dr. Wang and MD Anderson colleagues initiated a phase II trial at their institution with 50 patients age 65 years or under with newly diagnosed, CD20-positive and Cyclin D1-positive MCL.

A total of 50 patients age 65 years or younger (median age 54) with newly diagnosed, untreated MCL underwent induction with continuous daily ibrutinib 560 mg, plus rituximab 375 mg/m² administered weekly for 4 weeks during cycle 1 and on day 1 of cycles 3-12. Consolidation consisted of rituximab plus hyper-CVAD (hyper-fractionated cyclophosphamide, vincristine, doxorubicin, and dexamethasone), alternating every 28 days with rituximab plus high-dose methotrexate–cytarabine.

Patients who had complete responses to induction received four cycles of chemoimmunotherapy, while those who experienced disease progression and those who had partial responses received chemoimmunotherapy for two cycles beyond the point of complete remissions.

At the time of the presentation, all 50 patients were evaluable for the induction phase (part 2), and 47 were evaluable for both induction and consolidation (part 2) .Of the evaluable patients, the overall response rate (ORR) to chemotherapy-free induction therapy alone (Part 1 ) was 100% (50), with CR in 90% of patients and partial responses (PR) in 10%. Of the 47 patients evaluable for part 2 (chemoimmunotherapy), all had CRs, for an ORR of 100%.

Dr. Wang noted that one patient had a dramatic radiographic reduction in spleen size following just two cycles of chemotherapy-free induction, and two other patients had similar reductions after four and six cycles, respectively.

After a median follow-up of 15.9 months, neither the median duration of response, progression-free survival, nor overall survival have been reached. There have been no deaths and only one case of disease progression after one year of therapy.

The patients generally tolerated the regimen very well, Dr. Wang said. There were no cases of lymphocytosis, bleeding, or atrial fibrillation after 332 combined cycles.

Nonhematological adverse events were primarily grade 1 or 2. Grade 3 fatigue was reported in approximately 10% of patients. There were no grade 4 adverse events.

“This study may provide a window of opportunity to reduce the frontline therapies and reduce the long-term toxicities such as secondary malignancies.” Dr. Wang said.

He acknowledged that four cycles of intensive chemotherapy is still toxic and that further efforts to reduce these toxicities are needed. The investigators are currently planning the Window II study, in which a fraction of patients will be treated with no chemotherapy at all, he said.­­­­

The study was supported by Pharmacyclics and Janssen. Dr. Wang disclosed receiving research grants and honoraria and serving as a consultant for the companies.

LUGANO, SWITZERLAND – The chemotherapy-free combination of lenalidomide (Revlimid) and rituximab was highly active as frontline therapy for patients with low- and intermediate-risk follicular lymphoma in a multicenter phase II trial.

Among 66 patients with previously untreated follicular lymphoma, the overall response rate to the combination was 95%, including complete responses in 72% of patients. The 5-year progression-free survival (PFS) rate was 70%, reported John P. Leonard, MD, of Weill Cornell Medicine, New York.

“I think this overall is a useful validation – confirmation of the single-center data that showed that this [combination] in a multicenter setting can be a highly effective and reasonably well-tolerated treatment approach for patients with untreated follicular lymphoma,” he said at the International Conference on Malignant Lymphoma, on behalf of colleagues in the National Cancer Institute Alliance for Clinical Trials in Oncology and Cancer and Leukemia Group B (CALGB) 50803 trial.

LUGANO, SWITZERLAND – The chemotherapy-free combination of lenalidomide (Revlimid) and rituximab was highly active as frontline therapy for patients with low- and intermediate-risk follicular lymphoma in a multicenter phase II trial.

Among 66 patients with previously untreated follicular lymphoma, the overall response rate to the combination was 95%, including complete responses in 72% of patients. The 5-year progression-free survival (PFS) rate was 70%, reported John P. Leonard, MD, of Weill Cornell Medicine, New York.

“I think this overall is a useful validation – confirmation of the single-center data that showed that this [combination] in a multicenter setting can be a highly effective and reasonably well-tolerated treatment approach for patients with untreated follicular lymphoma,” he said at the International Conference on Malignant Lymphoma, on behalf of colleagues in the National Cancer Institute Alliance for Clinical Trials in Oncology and Cancer and Leukemia Group B (CALGB) 50803 trial.

LUGANO, SWITZERLAND – The chemotherapy-free combination of lenalidomide (Revlimid) and rituximab was highly active as frontline therapy for patients with low- and intermediate-risk follicular lymphoma in a multicenter phase II trial.

Among 66 patients with previously untreated follicular lymphoma, the overall response rate to the combination was 95%, including complete responses in 72% of patients. The 5-year progression-free survival (PFS) rate was 70%, reported John P. Leonard, MD, of Weill Cornell Medicine, New York.

“I think this overall is a useful validation – confirmation of the single-center data that showed that this [combination] in a multicenter setting can be a highly effective and reasonably well-tolerated treatment approach for patients with untreated follicular lymphoma,” he said at the International Conference on Malignant Lymphoma, on behalf of colleagues in the National Cancer Institute Alliance for Clinical Trials in Oncology and Cancer and Leukemia Group B (CALGB) 50803 trial.

Lugano, Switzerland– It’s in the BAG: For patients with treatment-naive or relapsed/refractory chronic lymphocytic leukemia, a regimen consisting of debulking with bendamustine (Treanda) followed sequentially by obinutuzumab (Gazyva) and venetoclax (Venclexta) was associated with a high overall response rate and a large majority of patients being negative for minimal residual disease (MRD) in peripheral blood.

In the open-label, phase II CLL2-BAG study in 66 patients, the overall response rate at the end of induction was 95%, and 87% of patients were negative for MRD, reported Paula Cramer, MD, of the University of Cologne (Germany).

“This sequential treatment of bendamustine followed by obinutuzumab and venetoclax does not lead to any cumulative or unexpected toxicity. As compared to other trials, it’s important to point out that only one laboratory TLS [tumor lysis syndrome] occurred with venetoclax. Maybe that’s explained by the sequential start of all three drugs,” she said at the International Conference on Malignant Lymphoma.

The trial is based on a concept the investigators call “sequential triple-T” (tailored and targeted treatment) aimed at complete eradication of MRD.

The 66 patients (median age, 59 years) had either previously untreated or relapsed/refractory CLL; 34 of the treatment-naive and 29 of the relapsed/refractory patients were evaluable for response.

At enrollment, patients who had an absolute lymphocyte count of 25,000/mcL or greater and/or lymph nodes 5 cm or larger received two cycles of debulking with bendamustine 70 mg/m² on days 1 and 2 every 28 days, unless this was contraindicated.

The induction phase consisted of obinutuzumab 1,000 mg administered three times in cycle 1, then every 4 weeks for cycles 2 through 6. Venetoclax was started during cycle 2 with a dose escalation to 400 mg daily over a period of 5 weeks.

Maintenance therapy consisted of daily venetoclax and obinutuzumab every 3 months until MRD negativity or up to 24 months.

A total of 45 patients (31 who were treatment naive and 14 with relapsed/refractory disease) underwent debulking. Of this group 36 patients received both cycles, and 9 discontinued early because of either adverse events (5 patients), disease progression (1), or unknown reasons (3).

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

Responses

In all, 24 patients (53%) who had debulking had a response during that phase based on International Workshop on CLL (IWCLL) criteria, for an overall response rate (ORR) of 53%. Thirteen patients had stable disease after debulking, and four had disease progression.

Responses after induction according to IWCLL criteria, the primary endpoint, included five patients with a complete response (three treatment-naive and two relapsed/refractory patients), and 20 patients (14 treatment-naive and six relapsed/refractory patients) with an unconfirmed or clinical complete response or a complete response with incomplete recovery of counts.

In addition, 35 patients (17 who were treatment naive and 18 with relapsed/refractory disease) had a partial response. No patients had stable disease, and three patients, all with relapsed/refractory disease, had disease progression.

Of the 63 patients who had at least two cycles of therapy, 87% were MRD negative. Eight patients had MRD assessments by bone marrow, and all eight were MRD negative.

The maintenance phase of the trial is ongoing and the data are not mature, but 56 patients (30 who were treatment naive and 26 with relapsed/refractory disease) have started on maintenance therapy. Of this group, 28 have stopped maintenance, including 21 patients who stopped because they achieved MRD negativity, 5 who discontinued because of adverse events, and 2 with disease progression or Richter’s transformation.

At 15 months of follow-up, progression-free survival was 100% in patients who received the combination as the frontline therapy, and 83% in the patients with relapsed/refractory disease.

Adverse events

In the debulking phase, 34 patients (72%) experienced adverse events of any grade, including 16 patients with grade 3 or 4 events

Adverse events associated with debulking included neutropenia and anemia, each seen in five patients, thrombocytopenia and infection each seen in three patients, and coronary artery disorders, rash, tumor lysis syndrome, vomiting, and pyrexia in one patient each.

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

All but 3 of the 63 patients had an adverse event, and 44 patients had at least one grade 3 or 4 adverse event.

Cytopenias, infections, infusion-related reactions, and neoplasms were the most common adverse events.

There were three grade 3 laboratory-confirmed cases of tumor lysis syndrome, one each occurring during bendamustine debulking, obinutuzumab administration, and venetoclax administration.

Something other than venetoclax?

Davide Rossi, MD, PhD, of the Oncology Institute of Southern Switzerland in Bellinzona, the invited discussant, questioned whether venetoclax is the best agent to use in sequential triple-T therapy.

“We know that venetoclax is more active in blood and bone marrow than in lymph nodes and, indeed, a proportion of cases achieving all the criteria for a CR [complete response] in the bone marrow and the peripheral blood, including MRD negativity, may still have some residual [disease in] lymph nodes,” he said.

Drugs that inhibit the B-cell receptor pathway may be more effective at eradicating MRD in the lymph node compartment, Dr. Cramer said.

The study was sponsored by the German CLL study group. Dr. Cramer disclosed financial ties to multiple entities. Dr. Rossi did not report disclosures.
 

Lugano, Switzerland– It’s in the BAG: For patients with treatment-naive or relapsed/refractory chronic lymphocytic leukemia, a regimen consisting of debulking with bendamustine (Treanda) followed sequentially by obinutuzumab (Gazyva) and venetoclax (Venclexta) was associated with a high overall response rate and a large majority of patients being negative for minimal residual disease (MRD) in peripheral blood.

In the open-label, phase II CLL2-BAG study in 66 patients, the overall response rate at the end of induction was 95%, and 87% of patients were negative for MRD, reported Paula Cramer, MD, of the University of Cologne (Germany).

“This sequential treatment of bendamustine followed by obinutuzumab and venetoclax does not lead to any cumulative or unexpected toxicity. As compared to other trials, it’s important to point out that only one laboratory TLS [tumor lysis syndrome] occurred with venetoclax. Maybe that’s explained by the sequential start of all three drugs,” she said at the International Conference on Malignant Lymphoma.

The trial is based on a concept the investigators call “sequential triple-T” (tailored and targeted treatment) aimed at complete eradication of MRD.

The 66 patients (median age, 59 years) had either previously untreated or relapsed/refractory CLL; 34 of the treatment-naive and 29 of the relapsed/refractory patients were evaluable for response.

At enrollment, patients who had an absolute lymphocyte count of 25,000/mcL or greater and/or lymph nodes 5 cm or larger received two cycles of debulking with bendamustine 70 mg/m² on days 1 and 2 every 28 days, unless this was contraindicated.

The induction phase consisted of obinutuzumab 1,000 mg administered three times in cycle 1, then every 4 weeks for cycles 2 through 6. Venetoclax was started during cycle 2 with a dose escalation to 400 mg daily over a period of 5 weeks.

Maintenance therapy consisted of daily venetoclax and obinutuzumab every 3 months until MRD negativity or up to 24 months.

A total of 45 patients (31 who were treatment naive and 14 with relapsed/refractory disease) underwent debulking. Of this group 36 patients received both cycles, and 9 discontinued early because of either adverse events (5 patients), disease progression (1), or unknown reasons (3).

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

Responses

In all, 24 patients (53%) who had debulking had a response during that phase based on International Workshop on CLL (IWCLL) criteria, for an overall response rate (ORR) of 53%. Thirteen patients had stable disease after debulking, and four had disease progression.

Responses after induction according to IWCLL criteria, the primary endpoint, included five patients with a complete response (three treatment-naive and two relapsed/refractory patients), and 20 patients (14 treatment-naive and six relapsed/refractory patients) with an unconfirmed or clinical complete response or a complete response with incomplete recovery of counts.

In addition, 35 patients (17 who were treatment naive and 18 with relapsed/refractory disease) had a partial response. No patients had stable disease, and three patients, all with relapsed/refractory disease, had disease progression.

Of the 63 patients who had at least two cycles of therapy, 87% were MRD negative. Eight patients had MRD assessments by bone marrow, and all eight were MRD negative.

The maintenance phase of the trial is ongoing and the data are not mature, but 56 patients (30 who were treatment naive and 26 with relapsed/refractory disease) have started on maintenance therapy. Of this group, 28 have stopped maintenance, including 21 patients who stopped because they achieved MRD negativity, 5 who discontinued because of adverse events, and 2 with disease progression or Richter’s transformation.

At 15 months of follow-up, progression-free survival was 100% in patients who received the combination as the frontline therapy, and 83% in the patients with relapsed/refractory disease.

Adverse events

In the debulking phase, 34 patients (72%) experienced adverse events of any grade, including 16 patients with grade 3 or 4 events

Adverse events associated with debulking included neutropenia and anemia, each seen in five patients, thrombocytopenia and infection each seen in three patients, and coronary artery disorders, rash, tumor lysis syndrome, vomiting, and pyrexia in one patient each.

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

All but 3 of the 63 patients had an adverse event, and 44 patients had at least one grade 3 or 4 adverse event.

Cytopenias, infections, infusion-related reactions, and neoplasms were the most common adverse events.

There were three grade 3 laboratory-confirmed cases of tumor lysis syndrome, one each occurring during bendamustine debulking, obinutuzumab administration, and venetoclax administration.

Something other than venetoclax?

Davide Rossi, MD, PhD, of the Oncology Institute of Southern Switzerland in Bellinzona, the invited discussant, questioned whether venetoclax is the best agent to use in sequential triple-T therapy.

“We know that venetoclax is more active in blood and bone marrow than in lymph nodes and, indeed, a proportion of cases achieving all the criteria for a CR [complete response] in the bone marrow and the peripheral blood, including MRD negativity, may still have some residual [disease in] lymph nodes,” he said.

Drugs that inhibit the B-cell receptor pathway may be more effective at eradicating MRD in the lymph node compartment, Dr. Cramer said.

The study was sponsored by the German CLL study group. Dr. Cramer disclosed financial ties to multiple entities. Dr. Rossi did not report disclosures.
 

Lugano, Switzerland– It’s in the BAG: For patients with treatment-naive or relapsed/refractory chronic lymphocytic leukemia, a regimen consisting of debulking with bendamustine (Treanda) followed sequentially by obinutuzumab (Gazyva) and venetoclax (Venclexta) was associated with a high overall response rate and a large majority of patients being negative for minimal residual disease (MRD) in peripheral blood.

In the open-label, phase II CLL2-BAG study in 66 patients, the overall response rate at the end of induction was 95%, and 87% of patients were negative for MRD, reported Paula Cramer, MD, of the University of Cologne (Germany).

“This sequential treatment of bendamustine followed by obinutuzumab and venetoclax does not lead to any cumulative or unexpected toxicity. As compared to other trials, it’s important to point out that only one laboratory TLS [tumor lysis syndrome] occurred with venetoclax. Maybe that’s explained by the sequential start of all three drugs,” she said at the International Conference on Malignant Lymphoma.

The trial is based on a concept the investigators call “sequential triple-T” (tailored and targeted treatment) aimed at complete eradication of MRD.

The 66 patients (median age, 59 years) had either previously untreated or relapsed/refractory CLL; 34 of the treatment-naive and 29 of the relapsed/refractory patients were evaluable for response.

At enrollment, patients who had an absolute lymphocyte count of 25,000/mcL or greater and/or lymph nodes 5 cm or larger received two cycles of debulking with bendamustine 70 mg/m² on days 1 and 2 every 28 days, unless this was contraindicated.

The induction phase consisted of obinutuzumab 1,000 mg administered three times in cycle 1, then every 4 weeks for cycles 2 through 6. Venetoclax was started during cycle 2 with a dose escalation to 400 mg daily over a period of 5 weeks.

Maintenance therapy consisted of daily venetoclax and obinutuzumab every 3 months until MRD negativity or up to 24 months.

A total of 45 patients (31 who were treatment naive and 14 with relapsed/refractory disease) underwent debulking. Of this group 36 patients received both cycles, and 9 discontinued early because of either adverse events (5 patients), disease progression (1), or unknown reasons (3).

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

Responses

In all, 24 patients (53%) who had debulking had a response during that phase based on International Workshop on CLL (IWCLL) criteria, for an overall response rate (ORR) of 53%. Thirteen patients had stable disease after debulking, and four had disease progression.

Responses after induction according to IWCLL criteria, the primary endpoint, included five patients with a complete response (three treatment-naive and two relapsed/refractory patients), and 20 patients (14 treatment-naive and six relapsed/refractory patients) with an unconfirmed or clinical complete response or a complete response with incomplete recovery of counts.

In addition, 35 patients (17 who were treatment naive and 18 with relapsed/refractory disease) had a partial response. No patients had stable disease, and three patients, all with relapsed/refractory disease, had disease progression.

Of the 63 patients who had at least two cycles of therapy, 87% were MRD negative. Eight patients had MRD assessments by bone marrow, and all eight were MRD negative.

The maintenance phase of the trial is ongoing and the data are not mature, but 56 patients (30 who were treatment naive and 26 with relapsed/refractory disease) have started on maintenance therapy. Of this group, 28 have stopped maintenance, including 21 patients who stopped because they achieved MRD negativity, 5 who discontinued because of adverse events, and 2 with disease progression or Richter’s transformation.

At 15 months of follow-up, progression-free survival was 100% in patients who received the combination as the frontline therapy, and 83% in the patients with relapsed/refractory disease.

Adverse events

In the debulking phase, 34 patients (72%) experienced adverse events of any grade, including 16 patients with grade 3 or 4 events

Adverse events associated with debulking included neutropenia and anemia, each seen in five patients, thrombocytopenia and infection each seen in three patients, and coronary artery disorders, rash, tumor lysis syndrome, vomiting, and pyrexia in one patient each.

Sixty of the 66 patients received the full six induction cycles. Three patients who had fewer than two cycles were excluded according to protocol. Of these three, two heavily pretreated patients died of sepsis and one of myocardial infarction in cycle 1.

All but 3 of the 63 patients had an adverse event, and 44 patients had at least one grade 3 or 4 adverse event.

Cytopenias, infections, infusion-related reactions, and neoplasms were the most common adverse events.

There were three grade 3 laboratory-confirmed cases of tumor lysis syndrome, one each occurring during bendamustine debulking, obinutuzumab administration, and venetoclax administration.

Something other than venetoclax?

Davide Rossi, MD, PhD, of the Oncology Institute of Southern Switzerland in Bellinzona, the invited discussant, questioned whether venetoclax is the best agent to use in sequential triple-T therapy.

“We know that venetoclax is more active in blood and bone marrow than in lymph nodes and, indeed, a proportion of cases achieving all the criteria for a CR [complete response] in the bone marrow and the peripheral blood, including MRD negativity, may still have some residual [disease in] lymph nodes,” he said.

Drugs that inhibit the B-cell receptor pathway may be more effective at eradicating MRD in the lymph node compartment, Dr. Cramer said.

The study was sponsored by the German CLL study group. Dr. Cramer disclosed financial ties to multiple entities. Dr. Rossi did not report disclosures.