European Commission Grants Conditional Marketing Authorization to Mosunetuzumab in R/R Follicular Lymphoma

Based on results from the phase 1/2 GO29781 trial, the European Commission has approved mosunetuzumab for adult patients with relapsed/refractory follicular lymphoma.

The European Commission has granted conditional marketing authorization to mosunetuzumab (Lunsumio) for adult patients with relapsed/refractory follicular lymphoma who have received 2 prior lines of therapy, according to a press release from Roche.1

The approval is based on results from the phase 1/2 GO29781 trial (NCT02500407) which investigated the safety and efficacy of mosunetuzumab monotherapy or combined with atezolizumab (Tecentriq) for those with follicular lymphoma and chronic lymphocytic leukemia. Currently, mosunetuzumab is the first CD20xCD3 T-cell–engaging bispecific antibody to be available for this patient population.

“Having additional treatment options for people with follicular lymphoma, where multiple prior lines of therapy have failed, is critical to help them achieve better outcomes,” Elizabeth Budde, MD, PhD, a hematologic oncologist and associate professor at City of Hope, said in the press release. “It is exciting to have a new class of immunotherapy like [mosunetuzumab], offering a readily available, chemotherapy-free and fixed-duration treatment, with great potential to provide durable remissions without the need to stay on treatment continuously.”

A high rate of complete response was reported that was maintained for at least 18 months. The complete response rate was 60%, and the objective response rate was 80%. The median follow-up was 18.3 months, the median duration of response was 22.8 months (95% CI, 9.7–not estimable). The most common adverse effect (AE) was cytokine release syndrome which was observed in 39% of patients, with 14% of events being grade 2; most events were resolved by the end of treatment. Additional AEs included neutropenia, pyrexia, hypophosphatemia, and headache.

This treatment has not been approved by the FDA in the United States, but it was granted breakthrough therapy designation on July 14, 2020, for the same indication.2


  1. European Commission approves Roche’s first-in-class bispecific antibody Lunsumio for people with relapsed or refractory follicular lymphoma. News Release. Roche. June 8, 2022. Accessed June 8, 2022.
  2. FDA grants breakthrough therapy designation for Roche’s CD20xCD3 bispecific cancer immunotherapy mosunetuzumab recognizing its potential in follicular lymphoma. News Release. Roche. July 14, 2022. Accessed June 8, 2022.