FDA Approves Mosunetuzumab-axgb for Follicular Lymphoma

The U.S. Food and Drug Administration (FDA) has approved mosunetuzumab-axgb for adult patients with relapsed or refractory follicular lymphoma after two or more lines of systemic therapy.

This indication for mosunetuzumab-axgb is approved under accelerated approval based on response rate. Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

Mosunetuzumab-axgb, a CD20xCD3 T-cell engaging bispecific antibody, is administered as an intravenous infusion for a fixed duration, which allows for time off therapy, and can be infused in an outpatient setting.

Its approval is based on positive results from the phase II GO29781 trial of mosunetuzumab-axgb in people with heavily pretreated follicular lymphoma, including those who were at high risk of disease progression or whose disease was refractory to prior therapies.

The investigators reported an objective response in 72/90 (80%) patients (95% CI, 70-88) who received mosunetuzumab-axgb, with a majority (57%) maintaining responses for at least 18 months (95% CI; 44-70).

The median duration of response among those who responded was almost two years (22.8 months; 95% CI, 10-not reached). A complete response was achieved in 54/90 (60%) patients (95% CI, 49-70) who recieved it. Among 218 patients with hematologic malignancies who received mosunetuzumab-axgb at the recommended dose, the most common adverse event (AE) was cytokine release syndrome (CRS; 39). The median duration of CRS events was 3 days (range, 1-29). Other common AEs (≥20%) included fatigue, rash, pyrexia, and headache.

Source: Business Wire, December 2022