KEY TAKEAWAYS
- The phase 1 & 2 trial aimed to investigate the efficacy and safety of Mosunetuzumab in treating patients with R/R follicular lymphoma after ≥ 2 prior therapies.
- Researchers noticed favorable safety profiles and outpatient suitability of Mosunetuzumab monotherapy for R/R B-cell NHL, including FL.
Mosunetuzumab is a CD20xCD3 T-cell engaging bispecific antibody approved in Europe and the United States for relapsed/refractory (R/R) follicular lymphoma (FL) after ≥ 2 prior therapies.
Matthew Matasar and the team aimed to investigate the efficacy and safety of Mosunetuzumab monotherapy as a treatment for R/R B-cell NHL, including FL.
They performed an inclusive analysis of interim safety data from the mosunetuzumab GO29781 phase I/II dose-escalation study in R/R NHL, specifically focusing on FL.
About 218 patients with R/R NHL, including 90 with R/R FL, underwent a median of eight 21-day cycles of intravenous mosunetuzumab with step-up dosing in Cycle 1 (Day 1: 1 mg; Day 8: 2 mg; Day 15/Day 1 of Cycle 2: 60 mg; Day 1 of Cycle 3 and onwards: 30 mg). Cytokine release syndrome (CRS) was the most frequent adverse event (AE), observed in 39.4% (NHL) and 44.4% (FL) of patients, mostly occurring during Cycle 1 at the first loading dose; the majority were grade 1/2. CRS events were managed with supportive care, steroids, and tocilizumab based on protocol guidelines.
Immune effector cell-associated neurotoxicity syndrome was rare, reported in 0.9% (NHL) and 1.1% (FL) of patients. Neutropenia occurred in 27.5% (NHL) and 28.9% (FL) of patients (mostly grade 3/4) and was effectively managed using granulocyte colony-stimulating factor. Tumor lysis syndrome occurred in 0.9% (NHL) and 1.1% (FL) of patients (all grade 3/4 with CRS; all resolved).
The study concluded that Mosunetuzumab monotherapy demonstrates promising results as a treatment option for R/R B-cell NHL, including FL, with low rates of severe AE’s, notably CRS. Moreover, its suitability for outpatient administration in community settings suggests a convenient therapeutic approach. The inclusion of adapted protocol guidance for managing select AEs further enhances the safety profile of Mosunetuzumab treatment.
The study was sponsored by the Genentech, Inc.
Source: https://pubmed.ncbi.nlm.nih.gov/38195322/
Clinical Trial: https://clinicaltrials.gov/study/NCT02500407
Matasar M, Bartlett NL, Shadman M, et al. (2024). “Mosunetuzumab Safety Profile in Patients With Relapsed/Refractory B-cell Non-Hodgkin Lymphoma: Clinical Management Experience From a Pivotal Phase I/II Trial.” Clin Lymphoma Myeloma Leuk. 2024 Apr;24(4):240-253. doi: 10.1016/j.clml.2023.12.005. Epub 2023 Dec 12. PMID: 38195322.
