ASH 2022: Phase I/II Results of CD3 Bispecific Antibody in Resistant Multiple Myeloma

By: Vanessa A. Carter, BS
Posted: Tuesday, December 13, 2022

Ajai Chari, MD, of Mount Sinai School of Medicine, New York, and colleagues aimed to evaluate talquetamab—a first-in-class, T-cell–redirecting bispecific antibody targeting both GPRC5D and CD3 receptors—for use in patients with relapsed or refractory multiple myeloma. Presented during the 2022 American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 157), the results of the MonumenTAL-1 trial suggest this antibody demonstrated manageable safety and “robust” efficacy in this population.

This phase I/II study enrolled 288 patients with measurable multiple myeloma whose disease progressed on or who were intolerant to standard therapies. Participants were administered 0.4 mg/kg (n = 143) or 0.8 mg/kg (n = 145) of subcutaneous talquetamab.

Baseline characteristics were similar among both treatment groups. Among patients treated with 0.4 mg/kg of talquetamab, the overall response rate was 73%, and responses appeared to deepen over time. With a median time to response of 1.2 months, the median time to a complete response was 2.1 months. Additionally, the median duration of response and progression-free survival were 9.3 months and 7.5 months, respectively.

The most common adverse events at doses of 0.4 mg/kg and 0.8 mg/kg included cytokine-release syndrome (79% and 72%), dysgeusia (48% and 46%), and anemia (45% and 39%). Skin-related adverse events (56% and 68%) and nail disorders (52% and 43%) were also prevalent in these treatment groups. Although limited to the first few treatment cycles, neutropenia occurred in 34% of patients who received 0.4 mg/kg of talquetamab and 28% of those administered 0.8 mg/kg; thrombocytopenia was detected in 27% of patients in each cohort.

Infections and dose reductions occurred more often in individuals who received 0.4 mg/kg (57% and 14.7%) than 0.8 mg/kg (50% and 6.2%). Of note, patients given 0.8 mg experienced higher rates of treatment discontinuation (6.2% vs. 4.9%) and dose delays (13.8% vs. 8.4%). The two reported deaths were related to COVID-19.

Disclosure: For full disclosures of the study authors, visit ash.confex.com.

2022 ASH Annual Meeting and Exposition

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