REAL-WORLD OUTCOMES OF TALQUETAMAB IN MONUMENTAL-1 TRIAL-INELIGIBLE VERSUS TRIAL-ELIGIBLE PATIENTS WITH RELAPSED/REFRACTORY MULTIPLE MYELOMA (RRMM)

J. Ramirez 1, R. Darji1, C. Wright1, K. Neupane 2, K. Harada 2, A. Dixon 2, B. Blue2, C. Freeman 2, F. Locke 2, T. Nishihori 2, J. Eatrides 2, L. Gardner 2, R. Baz 2, M. Alsina2, K. Shain 2, O. Castaneda 2, D. Hansen 2, A. Grajales-Cruz2

1. University of South Florida Morsani College of Medicine, Tampa, FL, USA

2. H. Lee Moffitt Cancer Center, Tampa, FL, USA

INTRODUCTION

Talquetamab is a GPRC5D × CD3 bispecific T-cell engager with demonstrated activity in heavily pretreated RRMM in the MonumenTAL-1 study. The efficacy of talquetamab among patients who would have been trial-ineligible, particularly after prior BCMA-directed therapy, remains clinically relevant as T-cell-redirecting therapies are used earlier in the treatment course.

Primary Objective

Compare talquetamab efficacy by retrospective MonumenTAL-1 eligibility

Secondary Objective

Evaluate outcomes after prior BCMA-directed therapy and describe real-world safety and treatment feasibility

METHODS:

Design: Single-center retrospective cohort

Setting: Moffitt Cancer Center, May 2023–November 2025

Population: 95 patients with RRMM; CAR-T bridging cases excluded

MonumenTAL-1 eligibility retrospectively adjudicated using published criteria

Responses assessed per IMWG criteria

Primary endpoint: ORR

Secondary endpoints: PFS, OS, DOR, safety

Kaplan-Meier/log-rank for time-to-event outcomes; Fisher’s exact test for ORR

CONCLUSIONS

85.3% of patients would not have met MonumenTAL-1 eligibility criteria despite largely preserved performance status (96.8% ECOG ≤2).

ORR was preserved across eligibility groups; PFS and OS were unexpectedly longer among patients who would not have met trial criteria. 

Survival differences are hypothesis-generating given the marked group imbalance (n = 14 vs n = 81) and potential physician treatment selection/selection bias.

SAFETY AND REAL WORLD FEASIBILITY

CRS: 38/95 patients (40.0%)

Grade ≥3 CRS: 3/95 (3.2%)

Median CRS grade: 2

Mean CRS-related hospitalization: 2.9 days

Prophylactic tocilizumab administered: 38/95

16 patients underwent outpatient step-up initiation

13/16 (81.3%) outpatient patients received prophylactic tocilizumab

No statistically significant difference in PFS or OS by prior BCMA exposure

ORR was similar between patients who would and would not have met the MonumenTAL-1 eligibility criteria.