Chugai Receives World-First Approval for Lunsumio-Polivy Combination in Relapsed Large B-Cell Lymphoma
Key Insights
Chugai Pharmaceutical obtained Japanese regulatory approval for the world's first combination therapy of Lunsumio and Polivy for relapsed or refractory large B-cell lymphoma (search).
The combination therapy achieved a 69.7% objective response rate and demonstrated a 59% reduction in disease progression risk compared to standard chemotherapy.
Approval was based on the Phase III SUNMO study results, targeting patients ineligible for autologous stem cell transplantation.
Chugai Pharmaceutical Co., Ltd. announced today that it received regulatory approval from Japan's Ministry of Health, Labour and Welfare (MHLW) for the combination therapy of Lunsumio (mosunetuzumab) and Polivy (polatuzumab vedotin) to treat relapsed or refractory large B-cell lymphoma (search). This marks the first global approval for this combination therapy in this indication.
The approval addresses a significant unmet medical need for patients with relapsed or refractory large B-cell lymphoma (search), where treatment options remain limited. "The Lunsumio and Polivy combination therapy achieved responses in approximately 70% of patients and showed a 59% reduction in the risk of disease progression or death compared to the chemotherapy control arm," said Dr. Osamu Okuda, Chugai's President and CEO.
Phase III SUNMO Study Results
The approval is based on results from the global, multicenter, randomized Phase III SUNMO study, which evaluated the combination therapy against rituximab, gemcitabine, and oxaliplatin (R-GemOx) in patients with relapsed or refractory large B-cell lymphoma (search) who are not eligible for autologous hematopoietic stem cell transplantation.
In the interim analysis, the objective response rate (ORR), a primary endpoint assessed by an independent review committee, was 69.7% (95% CI: 60.7-77.8) in the combination therapy group compared to 44.1% (95% CI: 31.2-57.6) in the R-GemOx group, representing a between-group difference of 25.7% (97.5% CI: 7.4-43.9).
The progression-free survival (PFS), also a primary endpoint, was 11.5 months (95% CI: 5.6-18) in the combination therapy group versus 3.8 months (95% CI: 2.9-4.1) in the R-GemOx group, demonstrating a 59% reduction in the risk of disease progression or death.
Safety Profile
The safety profile of the combination therapy was consistent with the known profiles of each individual agent. Adverse events were observed in 131 of 135 patients (97.0%) in the combination therapy group and in 61 of 64 patients (95.3%) in the R-GemOx group. The main adverse events in the combination therapy group included injection site reactions in 71 patients (52.6%), neutropenia in 62 patients (45.9%), anemia in 41 patients (30.4%), and cytokine release syndrome in 35 patients (25.9%).
Drug Mechanisms and Administration
Lunsumio is a T-cell-engaging bispecific antibody designed to target CD3 (search) on T cells and CD20 (search) on B cells, activating cytotoxic T cell-mediated immunity against CD20-expressing tumor cells. The drug has been approved in 65 countries worldwide and is administered subcutaneously in 21-day cycles, with 5 mg on Day 1 of the first cycle, followed by 45 mg on Days 8 and 15, and 45 mg on Day 1 from the second cycle onward for up to 8 cycles.
Polivy is a first-in-class anti-CD79b (search) antibody-drug conjugate (ADC) that binds to cancer cells expressing CD79b and delivers an anti-cancer agent to destroy B cells while minimizing effects on normal cells. It is administered intravenously at 1.8 mg/kg once every three weeks for a total of six doses.
Disease Context
Large B-cell lymphoma (search) consists primarily of diffuse large B-cell lymphoma (search) (DLBCL), the most common subtype of non-Hodgkin lymphoma (search) affecting B-cell lymphocytes. DLBCL accounts for approximately 80% of large B-cell lymphoma cases and is the most common form of aggressive non-Hodgkin lymphoma. The category also includes high-grade B-cell lymphoma (search), which is considered even more aggressive with a poorer prognosis than DLBCL. Although patients generally respond to frontline therapy, up to 40% experience relapse or become refractory, with limited treatment options available for salvage therapy.