Posted: Thursday, September 15, 2022
Treatment with fixed-duration mosunetuzumab appears to induce high rates of complete remission in patients with relapsed or refractory follicular lymphoma, according to a phase II study published in The Lancet Oncology. Mosunetuzumab, a CD20 × CD3 T-cell–engaging bispecific monoclonal antibody that redirects T cells to eliminate malignant B cells, also seemed to have a favorable safety profile—potentially allowing administration as an outpatient regimen.
“Mosunetuzumab represents an active and well-tolerated treatment option for patients with relapsed or refractory follicular lymphoma and two or more previous therapies that appears to be an advance in terms of anticancer activity, safety, and accessibility over the currently available therapies,” stated Nancy L. Bartlett, MD, of Washington University, St Louis, and colleagues.
In this single-arm, phase II study, 90 patients with relapsed or refractory follicular lymphoma who had received two or more previous therapies were given intravenous mosunetuzumab in 21-day cycles. Cycle 1 step-up dosing consisted of 1 mg on cycle 1 day 1, 2 mg on cycle 1 day 8, 60 mg on cycle 1 day 15 and cycle 2 day 1, and 30 mg on day 1 of cycle 3 and onward.
After a median follow-up of 18.3 months, 54 patients (60%) achieved a complete response. Of note, the observed complete response rate was significantly higher than the historical control complete response rate with the kinase inhibitor copanlisib of 14% (P < .0001).
The most common adverse event, cytokine-release syndrome (44%), was predominantly reported during step-up therapy during cycle 1. The most common grade 3 or 4 adverse events were neutropenia or a decreased neutrophil count (27%), hypophosphatemia (17%), hyperglycemia (8%), and anemia (8%).
Disclosure: For full disclosures of the study authors, visit www.thelancet.com.