Chugai Pharma’s mosunetuzumab accomplishes the primary endpoint in expansion cohort of the Japanese phase I trial for r/r follicular lymphoma

Chugai Pharmaceutical Co., Ltd. announced that the anti-CD20/CD3 bispecific antibody mosunetuzumab met the primary endpoint of complete response rate (CRR) in a Japanese phase I expansion cohort studying relapsed or refractory (R/R) follicular lymphoma (FL) patients who received at least two prior systemic therapies. Safety profiles aligned with overseas studies.

R/R FL poses challenges in achieving a cure, necessitating novel treatments. Chugai plans to submit a new drug application in Japan based on positive results from this and Roche's overseas trials.

The Japanese phase I trial assessed mosunetuzumab's efficacy and safety in dose-escalation and expansion cohorts for R/R FL patients with two or more prior systemic therapies. The expansion cohort included 19 patients, with CRR as the primary endpoint and secondary endpoints such as overall response rate and progression-free survival.

Mosunetuzumab, a CD20xCD3 bispecific antibody, targets CD20 on B cells and CD3 on T cells, activating cytotoxic T cells to combat CD20-expressing tumor cells. It's being developed for R/R FL and R/R aggressive B-cell non-Hodgkin lymphoma, addressing a critical need for more effective treatments. FL affects approximately 5,000 people yearly in Japan.