What were the long-term outcomes of fixed-duration mosunetuzumab in B-NHL?

The Lymphoma Hub was pleased to speak to Elizabeth Budde, City of Hope Comprehensive Cancer Center, Duarte, US. We asked about the long-term outcomes of fixed-duration mosunetuzumab in B-cell non-Hodgkin lymphoma (B-NHL).

In this interview, Dr Budde discusses the long-term outcomes of treatment with fixed-duration mosunetuzumab in patients with B-NHL, with a focus on follicular lymphoma. Budde reviews the efficacy and safety data from the extended follow-up of the phase II GO29781 (NCT02500407) dose-escalation study, addressing duration of response, remission, overall survival (OS), and CD19-positive B-cell recovery. Budde also describes the characteristics of mosunetuzumab, including its outpatient administration and minimal steroid use.

Key points and data from GO29781*

• Mosunetuzumab is a CD20/CD3 bispecific T-cell engager that directs T cells to target malignant B cells, administered in an outpatient setting with minimal steroid use.
• Mosunetuzumab was administered at a fixed duration of 8 cycles, with each cycle lasting 21 days.
• At a median follow-up of 37.4 months, the median duration of response among 70 responders was 36 months, while the median duration of complete response was not reached.
• The 30-month remission rate was 72.4%.
• The estimated 36-month OS rate was 82.4%, with median OS not reached.
• The median time to CD19-positive B-cell recovery following treatment was 18.4 months.
• No new safety concerns were identified in this extended follow-up.
• Patients retreated with mosunetuzumab post an initial response to mosunetuzumab were also analyzed and high response rates were observed with retreatment.
• These findings support the continued use of mosunetuzumab as a fixed-duration treatment for patients with relapsed or refractory follicular lymphoma in the outpatient setting.
• The data include patients with high-risk disease, such as those refractory to previous therapies or with high-risk molecular features, including the TP53 mutation.

*Data submitted for publication.