By: Kerri Fitzgerald
Follow-up results from the BELLWAVE-003 study assessing nemtabrutinib in patients with hematologic malignancies showed continued antitumor activity and no new safety concerns with the noncovalent, reversible Bruton’s tyrosine kinase inhibitor.
Wojciech Jurczak, MD, PhD, of the Maria-Sklodowska-Curie National Research Institute of Oncology in Krakow, Poland, presented the findings at the 2025 EHA Congress.
The multicenter, open-label, single-arm, phase 2 BELLWAVE-003 study enrolled patients with relapsed or refractory hematologic malignancies. Those with follicular lymphoma (FL) who did respond to or tolerate chemoimmunotherapy and immunomodulatory agents received nemtabrutinib at the recommended phase 2 dose of 65 mg orally daily until unacceptable toxicity, disease progression, or withdrawal.
As of January 3, 2025, 49 patients in this cohort received treatment, with a median follow-up of 11.3 months (range, 0.2-22.4). Median age was 59 years (range, 33-80), 55% were male, and 57% had Lugano stage 4 disease. Patients received a median of 4 prior therapies (range, 1-11), and median time on therapy was 3.8 months (range, 0.2-15.6).
Among 41 evaluable patients, the overall response rate was 39%: 2 (5%) had a complete response and 14 (34%) had a partial response. Median duration of response was 5.8 months, and median time to response was 2.8 months.
Median progression-free and overall survival (OS) were not reached. The 12-month OS rate was 87%.
Most patients (n=45; 92%) experienced any-grade adverse events (AEs), the most common of which were decreased neutrophil count (n=12; 25%) and decreased platelet count (n=10; 20%).
Nearly half (n=20; 41%) of patients experienced grade 3-5 AEs, the most common which were decreased neutrophil count (n=5; 10%), neutropenia (n=3; 6%), decreased platelet count (n=3; 6%), and thrombocytopenia (n=3; 6%).
AEs led to dose reductions in 3 participants, discontinuations in 5 participants, and death in 1 participant. No drug-related AEs resulted in death.
Reference
Jurczak W, Basquiera A, Fleury I, et al. Efficacy and safety of nemtabrutinib in relapsed or refractory follicular lymphoma: updated analysis of cohort G of the phase 2 BELLWAVE-003 study. Abstract #PS1887. Presented at the European Hematology Association 2025 Congress; June 12-15, 2025; Milan, Italy.
