Efficacy of isatuximab with pomalidomide and dexamethasone in relapsed myeloma: Results of a UK-wide real-world dataset

Abstract

Real-world data on the efficacy and tolerability of isatuximab with pomalidomide and dexamethasone (IsaPomDex) in relapsed/refractory myeloma (RRMM) patients have not been reported. In this UK-wide retrospective study, IsaPomDex outcomes were evaluated across 24 routine care cancer centres. The primary endpoint was overall response rate (ORR). Secondary endpoints included progression-free survival (PFS), duration of response (DOR) for patients who achieved an objective response (≥PR), and adverse events (AEs). In a total cohort 107 patients, median follow up (IQR) was 12.1 months (10.1-18.6 months), median age (IQR) was 69 years (61-77). Median (IQR) Charlson Co-morbidity index (CCI) score was 3 (2- 4); 43% had e-GFR<60 ml/min. Median (IQR) number of prior therapies was 3 (3-3). Median (IQR) number of IsaPomDex cycles administered was 7 (3-13). ORR was 66.4%, with responses categorised as ≥VGPR: 31.8%, PR: 34.6%, SD: 15.9%, PD: 15% and unknown 2.8%. Median PFS was 10.9 months. Median DOR was 10.3 months There was no statistical difference in median PFS by age (<65: 10.2 vs. 65-74 13.2 vs. ≥75: 8.5 months, log-rank p=0.4157), by CCI score (<4: 10.2 months vs. ≥4: 13.2, log-rank p=0.6531), but inferior PFS was observed with renal impairment (≥60: 13.2 vs. <60: 7.9 months, log-rank p=0.0408). Median OS was 18.8 months. After a median of 4 cycles, any grade AEs were experienced by 87.9% of patients. The most common ≥G3 AEs were neutropenia (45.8%), infections (18.7%) and thrombocytopenia (14%). Our UK-wide IsaPomDex study demonstrated encouraging efficacy outcomes in the real-world, comparable to ICARIA-MM trial.