Posted: Tuesday, June 6, 2023
The phase Ib RedirecTT-1 trial, performed by Yael C. Cohen, MD, of Tel-Aviv Sourasky Medical Center, Sackler School of Medicine, Tel Aviv University, Israel, and colleagues, evaluated the simultaneous use of B-cell maturation agent (BCMA)- and GPRC5D-targeted therapy in patients with relapsed or refractory multiple myeloma. During the 2023 American Society of Clinical Oncology (ASCO) Annual Meeting (Abstract 8002), the investigators presented their first results with the hope that the combination of teclistamab and talquetamab may improve patient outcomes.
“In this first combination study of a BCMA- and GPRC5D-targeted bispecific antibody, teclistamab and talquetamab at the recommended phase II regimen has a manageable safety profile consistent with each of the monotherapies,” the authors concluded. “A 92% overall response rate was observed in [these patients] at the recommended phase II regimen, and an overall response rate of 83% was achieved in [patients] with extramedullary disease…, supporting further evaluation of the combination.”
A total of 63 patients with relapsed or refractory multiple myeloma were enrolled. Primary endpoints of this study included safety evaluation and identification of a recommended phase II regimen for the combination (ClinicalTrials.gov identifier NCT04586426).
Most patients had triple-class–refractory (78%) and/or penta-drug–exposed (63%) disease; 43% had extramedullary disease, and 33% had high-risk cytogenetics. At the median follow-up of 14.4 months, the most common treatment-emergent adverse event was cytokine-release syndrome, followed by neutropenia and anemia. Dose-limiting toxicities included grade 3 herpetic stomatitis at dose level one, as well as immune effector cell–associated neurotoxicity syndrome and aspartate transaminase/alanine transaminase elevation; none were reported at the recommended phase II regimen.
The overall response rate across all dose levels was 84% among all patients and 73% among those with extramedullary disease. Of note, the rates of complete response or better were 34% and 31% for all patients and those with extramedullary disease, respectively; rates were similar at the recommended phase II regimen.
Disclosure: For full disclosures of the study authors, visit coi.asco.org.