Real‐world outcomes in relapsed refractory multiple myeloma patients exposed to three or more prior treatments: an analysis from the ANZ myeloma and related diseases registry

Abstract

AbstractBackgroundThere is no currently available standard of care for triple‐class exposed, relapsed refractory myeloma (RRMM) patients in Australia. CARTITUDE‐1 (CART‐1) was a single‐arm, phase 1b/2 study of 97 triple‐class exposed RRMM patients, who received BCMA‐CAR‐T cell therapy with ciltacabtagene autocel. Overall response rate (ORR) was 98%. Median progression free survival (PFS) and overall survival (OS) had not been reached at a median follow‐up of 28 months.MethodsWe performed a retrospective analysis on a cohort of CART‐1 comparable RRMM patients participating in the Australian and New Zealand Myeloma and Related Diseases Registry (MRDR), to compare outcomes in triple‐class exposed MM patients treated with currently available therapies, in a real‐world context. The CE‐MRDR cohort (n = 28) fulfilled CARTITUDE‐1 eligibility (CE) criteria: ≥3 lines of therapy (LOT) including an immunomodulatory agent, proteasome inhibitor and CD38‐directed monoclonal antibody (CD38mAb) and Eastern Cooperative Oncology Group Performance Status (ECOG PS) score of 0–2 at diagnosis. The modified‐CE‐MRDR (n = 132) received ≥3 LOT but may not have received a CD38mAb with an ECOG PS score of 3 (0–3).ResultsResponses to the first subsequent therapy after eligibility were poor – ORR was 23% and 0% with progressive disease (PD) reported in 61% and 36%, CE‐MRDR and m‐CE‐MRDR respectively. Responses to the second subsequent therapy after eligibility were worse, ORR 0% and 31%, CE‐MRDR and m‐CE‐MRDR respectively, with high rates of PD, particularly in CE‐MRDR. Median OS was 5.4 versus 9.5 months, CE‐MRDR versus m‐CE‐MRDR.ConclusionsThis retrospective analysis confirms uniformly poor outcomes for Australian RRMM patients. There remains a critical need for greater accessibility to novel treatments, such as CAR‐T, outside clinical trials.