Clinically meaningful outcomes for mosunetuzumab across follicular lymphoma subgroups

High-risk participants with heavily pre-treated relapsed or refractory follicular lymphoma (RR FL) benefitted from mosunetuzumab for clinical remission and survival outcomes in a phase 1/2 study. The benefit of mosunetuzumab was consistent in participants who had disease progression within 2 years.

The phase 1/2 study (NCT02500407) recently demonstrated high complete response (CR) rates with the CD20/CD3 T-cell engaging bispecific antibody mosunetuzumab among patients with RR FL [1]. Dr Sarit Assouline (Jewish General Hospital, Canada) presented the current subgroup analysis of this study after 3 years of follow-up [2]. All participants received mosunetuzumab in the third line or later and progression of disease within 24 months (POD24) was observed in 52% of participants.

After 3 years of therapy, CR was seen in 60% of participants with POD24, a figure consistent with the overall study population (also 60%). Similarly, CR rates in participants older than 64 years (67%) and those who received mosunetuzumab as fourth-line therapy or later (55%) were comparable with the general trial population. In addition, the median duration of CR was not reached in participants with POD24 or older participants but was 33 months in ‘fourth-line-or-higher’ participants. The 3-year progression-free survival rates were 44% in the POD24 subgroup, 47% in participants over 64 years, and 43% in the overall population. In fourth-line-or-higher participants, this rate appeared lower at 36% compared with third-line participants (54%).

The safety profile of mosunetuzumab was manageable and consistent across subgroups. The observed adverse events were cytokine release syndrome (44%), neutropenia (29%), and serious infections (20%).

“The consistent results of mosunetuzumab across subgroups of participants with RR FL and the manageable safety profile support outpatient administration of this agent,” concluded Dr Assouline.

1. Budde LE, et al. Lancet Oncol. 2022;23(8):1055–1065.
2. Assouline S, et al. Mosunetuzumab demonstrates clinically meaningful outcomes in high-risk patients with heavily pre-treated R/R FL after ≥3 years of follow-up: subgroup analysis of a pivotal phase 2 study. S233, EHA congress 2024, 13–16 June, Madrid, Spain.

Copyright ©2024 Medicom Medical Publishers



Posted on 12 August 2024