Posted: Wednesday, August 2, 2023
Teclistamab—a B-cell maturation antigen (BCMA) x CD3 bispecific antibody approved in the United States for patients with relapsed or refractory multiple myeloma who previously received at least four lines of therapy, including a proteasome inhibitor, an immunomodulatory agent, and an anti-CD38 monoclonal antibody—seems to be active in those who had received prior anti-BCMA therapies, according to Ross Firestone, MD, of the Memorial Sloan Kettering Cancer Center, New York, and colleagues. However, the results of this retrospective analysis, which were presented during the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 8049), also suggested that exposure to multiple anti-BCMA therapies may be predictive of diminished efficacy.
“The approval was based on the results of the MajesTec-1 study; patients with prior exposure to anti-BCMA therapies…were excluded,” the investigators commented. “To our knowledge, this is the first report of commercial teclistamab in relapsed or refractory multiple myeloma.”
The investigators identified 24 patients who were treated with commercial teclistamab. Of this population, 10 underwent prior anti-BCMA therapy: 7 received belantamab mafodotin-blmf; 8 received BCMA-directed chimeric antigen receptor T-cell therapy; and 1 received BCMA-directed bispecific antibody therapy. A total of 15 patients were evaluable for response with at least 1 month of follow-up. Follow-up data were provided for a median of 1.3 months.
The objective response rates were 60% and 50% in all patients and in those who had anti-BCMA therapy, respectively. Patients who received at least two anti-BCMA therapies exhibited a 40% response rate. In all patients, the clinical benefit rate was 73%. None of the responders experienced disease progression.
Cytokine-release syndrome was reported in 41% of patients during step-up dosing; in this population, the clinical benefit and objective response rates were 100% and 71%, respectively. According to the investigators, two patients experienced grade 2 neurotoxicity, which improved after treatment discontinuation.
Disclosure: Dr. Firestone reported no conflicts of interest. For full disclosures of the other study authors, visit coi.asco.org.