Targeting GPRC5D With Talquetamab: A New Frontier in Bispecific Antibody Therapy for Relapsed/Refractory Multiple Myeloma

Objective: To evaluate the pharmacology, clinical efficacy, safety, dosing, administration, and clinical implications of talquetamab-tgvs, a novel bispecific antibody, in the treatment of relapsed or refractory (R/R) multiple myeloma (MM). Data Sources: A comprehensive English-language literature search of PubMed and Clinicaltrials.gov from January 2000 to May 2024 was conducted using the terms talquetamab, Talvey, JNJ-64407564, and “Multiple Myeloma.” Study Selection and Data Extraction: Relevant clinical trials, guidelines, and prescribing information were systematically reviewed and analyzed. Data Synthesis: Talquetamab-tgvs received accelerated approval from the United States Food and Drug Administration based on results from the pivotal phase I/II MonumenTAL-1 clinical trial, which demonstrated an overall response rate of nearly 74% in key cohorts. The median progression-free survival was 7.5 months in the 0.4 mg/kg weekly dosing cohort and 11.9 months in the 0.8 mg/kg biweekly dosing cohort. Treatment-related adverse events (AEs) included cytokine release syndrome, skin- and nail-related AEs, dysgeusia, infections, and immune effector cell-associated neurotoxicity syndrome. Relevance to Patient Care and Clinical Practice: As a first-in-class anti-GPRC5D T-cell-redirecting bispecific antibody, talquetamab-tgvs represents a compelling treatment option for patients with R/R MM who have received at least 4 prior lines of therapy. No head-to-head clinical trials have been conducted comparing talquetamab-tgvs to other T-cell-redirecting therapies. Conclusions: While talquetamab-tgvs showed significant efficacy in the pivotal MonumenTAL-1 trial, long-term safety and efficacy data are needed. Additional clinical trials are necessary to establish the optimal timing, sequencing, patient population, and overall role of talquetamab-tgvs in the rapidly evolving treatment landscape of R/R MM.