Roche Lunsumio (Mosunetuzumab, CD20xCD3 Bispecific Antibody) Plus Lenalidomide Meets Progression-Free-Survival Primary Endpoint in Phase 3 CELESTIMO Trial in Relapsed/Refractory Follicular Lymphoma
Roche (SIX: ROG; OTCQX: RHHBY) announced Thursday September 17, 2026 that the Phase 3 CELESTIMO trial evaluating Lunsumio (mosunetuzumab, an anti-CD20 x anti-CD3 T-cell-engaging bispecific antibody) plus lenalidomide versus MabThera/Rituxan (rituximab) plus lenalidomide (R2 regimen) in adults with relapsed or refractory follicular lymphoma (R/R FL) who received at least one prior line of treatment met its primary endpoint, showing a statistically significant improvement in progression-free survival (PFS). Overall survival data were immature at the interim analysis. The safety profile of the Lunsumio + lenalidomide combination was consistent with the known profiles of the individual agents, with no new safety signals. Data will be submitted to global health authorities and presented at an upcoming medical meeting. Lunsumio was FDA-approved in December 2022 for third-line-plus R/R FL as a monotherapy; a positive earlier-line CELESTIMO readout positions the drug to challenge the R2 standard-of-care regimen in second-line R/R FL, an approximately $1 billion sales opportunity in the U.S. alone.