Cellular and T cell engager Immunotherapy

Category: Cellular and T cell engager Immunotherapy

Racial and ethnic differences in outcomes of multiple myeloma patients treated with Teclistamab

(PA-087) Racial and Ethnic Differences in Outcomes of Multiple Myeloma Patients Treated with Teclistamab

Wednesday, September 17, 2025

Alicia R. Richards, PhD (she/her/hers)

Applied Research Scientist II
Moffitt Cancer Center

Introduction: Prior studies have identified racial and ethnic differences in clinical outcomes with CAR T-cell therapies in relapsed/refractory multiple myeloma (RRMM), but less work has focused on bispecific antibody therapy. We investigated racial and ethnic differences in safety and efficacy for patients with RRMM treated with standard of care teclistamab.

Methods: Data for Non-Hispanic (NH) Black, NH White, and Hispanic patients treated with teclistamab from August 9, 2022, to January 1, 2024, were obtained from 16 institutions in the U.S. Multiple Myeloma Immunotherapy Consortium. Other racial and ethnic groups were not included due to small sample sizes which precluded meaningful statistical comparisons. Patient characteristics, safety, and therapy response were examined by race and ethnicity using chi-square, Fisher exact, and Kruskal-Wallis rank sum tests. Kaplan-Meier curves and log-rank tests were used to examine overall survival (OS) and progression-free survival (PFS) by race and ethnicity.

Results: Of the 475 patients treated with teclistamab, NH Black and Hispanic patients comprised 20% (n=95) and 8% (n=39) of the cohort, respectively. Hispanic patients were younger than NH Black and White patients (median age 61 vs 65 vs 70 years; p< 0.001). NH Black patients had higher baseline absolute lymphocyte counts compared to Hispanic and NH White patients (1.0 vs 0.8 vs 0.6 k/uL; p< 0.001). No racial and ethnic differences in high-risk disease features and baseline cytopenias were observed. NH Black and Hispanic patients were more likely to have cytokine release syndrome (CRS) compared to NH White patients (64% vs 69% vs 49%; p=0.005), with a higher rate of ≥ grade 3 CRS in Hispanic patients compared to NH White and NH Black patients (3% vs 1% vs 1%; p=0.01). NH Black and Hispanic patients were more likely to have grade ≥ 3 neutropenia post-therapy (47% vs 65% vs 39%; p=0.04) and severe infections requiring hospitalization or IV antibiotics (33% vs 36% vs 20%; p=0.009) compared to NH White patients. NH Black patients were less likely to achieve a complete response at 3 months compared to NH White and Hispanic patients (7% vs 18% vs 15%; p=0.04) but no racial and ethnic differences in best response were observed. Median follow-up was 7.6 months, and PFS and OS were similar across racial and ethnic groups. No other differences in baseline patient characteristics and outcomes were observed by race and ethnicity (p >0.05).

Conclusions: Among patients with RRMM treated with teclistamab, NH Black and Hispanic patients experienced a higher rate of safety events and NH Black patients had lower complete response rates at 3 months compared to NH White patients but no differences in best response or survival were observed. These findings highlight the need for additional investigation into contributors to racial and ethnic differences in toxicity and early treatment response.