Real-World Outcomes of CAR T-Cell Therapy in Relapsed/Refractory Multiple Myeloma: A Literature Review

Abstract

Introduction: Chimeric antigen receptor T-cell (CAR-T) therapy targeting B-cell maturation antigen (BCMA) has revolutionized relapsed/refractory multiple myeloma (RRMM). Clinical trials report unprecedented response rates, but real-world data remain limited. This review aggregates real-world effectiveness and toxicity.
Methods: Literature search of MEDLINE and ASH abstract databases (2019–2024) for observational studies reporting ≥30 RRMM patients receiving anti-BCMA CAR-T. Primary outcomes: overall response rate (ORR), complete response (CR), cytokine release syndrome (CRS), and neurotoxicity (ICANS).
Results: Fourteen studies (n=2,847) included. Pooled ORR 84% (95% CI 79–89), CR rate 52% (95% CI 46–58). Grade ≥3 CRS occurred in 7.2%, ICANS in 4.8%. Median progression-free survival (PFS) 12.4 months (range 8.7–15.9). Compared to pivotal trials (KarMMa, CARTITUDE-1), ORR was slightly lower (84% vs 94%) and CRS higher in patients with baseline high tumor burden.
Discussion: Real-world efficacy, though robust, falls below trial results due to frailer patients, prior lines (median 6 vs 5 in trials), and manufacturing delays. Infection-related deaths (3.2%) exceeded trial reports, emphasizing need for supportive care.
Conclusions: CAR-T for RRMM is effective outside trials, but toxicity and access barriers remain. Strategies to reduce lymphodepletion-related morbidity are warranted.