MM-086 Real-World Experience With Isatuximab (Isa) in Patients With Relapsed and/or Refractory Multiple Myeloma: IONA-MM First Interim Analysis

Context: Based on Phase 3 ICARIA-MM and IKEMA studies, Isatuximab+pomalidomide+dexamethasone (Isa-Pd) or Isa+carfilzomib+dexamethasone (Isa-Kd), respectively, are approved for patients with relapsed and/or refractory multiple myeloma (RRMM). Limited real-world evidence (RWE) exists for patients treated with Isa-Pd/Isa-Kd. Objective: Describe baseline characteristics, treatment exposure, and treatment-emergent adverse events (TEAEs) for Isa-treated RRMM patients in a real-world setting. Design: First interim analysis of non-interventional IONA-MM study (NCT04458831). Patients and Setting: RRMM patients ≥18 years who received ≥1 prior treatment line were enrolled prospectively/retrospectively (Isa-exposed ≤3 months pre-enrollment). Treating physicians determined Isa treatment before and independent of enrollment; treatment duration was based on local prescribing regulations. Adverse events (AEs) and laboratory abnormalities were graded according to CTCAE v5.0. Results: Between 13-Aug-2020 and 22-Feb-2022, 112 patients (38 sites, 6 countries) received ≥1 dose of Isa-Pd (n=81), Isa-Kd (n=26), or other Isa regimens (n=5). Compared with baseline characteristics in Phase 3 Isa studies, a higher proportion of Isa-Pd/Isa-Kd patients in IONA-MM were ≥75 years old and ISS stage III, a lower proportion of Isa-Kd patients had high-risk cytogenetics, and 31.5% of Isa-Pd and 23.1% of Isa-Kd patients received ≥4 prior lines of therapy. Data on prior treatments and study drugs' relative dose intensities will be shared at the Congress. At data cutoff, median (min–max) duration of Isa exposure was 5.4 (0–18.8) and 6.2 (0–10.6) months, with 79.0% and 74.1% of patients still receiving Isa-Pd and Isa-Kd, respectively. For Isa-Pd and Isa-Kd, all-grade TEAEs occurred in 52 (64.2%) and 16 (61.5%); Grade 3–4 TEAEs in 36 (44.4%) and 10 (38.5%); serious TEAEs in 21 (25.9%) and 8 (30.8%); fatal TEAEs during study treatment in 4 (4.9%; sepsis [2], septic shock [1], failure to thrive [1]) and 1 (3.8%; pneumonia); and TEAEs leading to Isa discontinuation in 6 (7.4%) and 3 (11.5%) patients, respectively. Response data are forthcoming. Conclusions: In IONA-MM first interim analysis, we report comparable baseline characteristics to those seen in ICARIA-MM/IKEMA with few imbalances. Isa-Pd/ Isa-Kd have manageable safety profiles in routine clinical practice. These data provide RWE to support Isa use in RRMM outside clinical trials and in wider populations. Enrollment in IONA-MM is ongoing until sample size n=1,100 is reached.