ASCO 2021: Early Trial Update of Teclistamab in Resistant Multiple Myeloma
Posted: Tuesday, June 29, 2021
According to Amrita Y. Krishnan, MD, of the City of Hope Comprehensive Cancer Center, Duarte, California, and colleagues, the B-cell maturation antigen (BCMA)/CD3-bispecific IgG4 antibody teclistamab demonstrated “encouraging” efficacy and was reported to be well tolerated at the recommended phase II dose in patients with relapsed or refractory multiple myeloma. The updated results of this first-in-human, phase I trial, which were presented during the 2021 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 8007), support further investigation of this novel agent as monotherapy and in combination with other drugs. Based on these early results, the U.S. Food and Drug Administration recently granted teclistamab Breakthrough Therapy designation for treatment of this patient population.
Teclistamab was intravenously (n = 84) or subcutaneously (n = 72) administered, with step-up dosing used for doses of at least 38.4 µg/kg. The recommended phase II dose was identified as 1,500 µg/kg weekly via subcutaneous injection in part one of the trial. In part two, the investigators sought to examine the safety and tolerability of this agent at the recommended phase II dose. A total of 40 patients were administered the recommended phase II dose, with 60- and 300-µg/kg step-up doses.
In part one, no dose-limiting toxicities were reported at the recommended phase II dose. Cytokine-release syndrome (70%) and neutropenia (60%) were the most frequently reported adverse events at the recommended phase II dose; one patient experienced grade 1 neurotoxicity. The median duration of time to onset of cytokine-release syndrome was later with subcutaneous injection than with intravenous infusion.
The overall response rate was 65% at the recommended phase II dose; the median duration of the time to the first confirmed response was 1 month. At the recommended phase II dose, the median duration of response was not reached; the majority of responders (88%) were alive and continuing on treatment after a median follow-up of 5.3 months. Exposure was maintained across the dosing interval and exceeded target levels; consistent T-cell activation was reported.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.
