Subcutaneous, On-Body Delivery of Isatuximab-irfc for Resistant Multiple Myeloma

By: Julia Fiederlein Cipriano
Posted: Wednesday, January 25, 2023

Based on the updated follow-up data from an expansion cohort of a multicenter phase Ib trial, which were presented during the 2022 American Society of Hematology (ASH) Annual Meeting and Exposition (Abstract 1923), subcutaneous administration of the anti-CD38 monoclonal antibody isatuximab-irfc via a wearable bolus injector applied to the abdomen by a health-care professional, seems to elicit comparable efficacy and safety to the intravenous formulation when combined with pomalidomide and dexamethasone in patients with relapsed or refractory multiple myeloma. Hang Quach, MBBS, FRACP, FRCPA, MD, of the University of Melbourne, Australia, and colleagues suggested this approach may optimize the convenience of administration and enhance quality of life.

“[Subcutaneous, on-body delivery of isatuximab] is well tolerated, has a short duration of injection, and provides a convenient, hands-free option with controlled delivery,” the investigators remarked.

Patients were randomly assigned to a treatment: 10 mg/kg of intravenous isatuximab (n = 12); 1,000 mg of subcutaneous isatuximab (n = 12); the recommended phase II dose of 1,400 mg of subcutaneous isatuximab (n = 10); or 1,400 mg of subcutaneous, on-body–delivered isatuximab (n = 22). Treatment-related, treatment-emergent adverse events of grade 3 or 4 were reported in 91.7% of the 1,000-mg subcutaneous arm and approximately 80.0% of the 1,400-mg subcutaneous, intravenous, and on-body arms. Serious treatment-related, treatment-emergent adverse events occurred in 25.0%, 50.0%, 16.7%, and 13.6% of patients, respectively. No infusion reactions were observed with the on-body delivery system. A total of 22.7% of patients experienced injection-site reactions, all of which were grade 1.

According to the investigators, flat subcutaneous dosing resulted in variability in isatuximab pharmacokinetic exposure generally comparable to body weight–based intravenous dosing. Patients treated with the recommended phase II dose experienced an improved overall response rate (75.0%) versus those who received 1,000 mg of subcutaneous (66.7%) and intravenous (66.7%) isatuximab. In the intravenous, 1,000-mg subcutaneous, 1,400-mg subcutaneous, and on-body arms, the median durations of progression-free survival in months were 22.0, 12.5, not calculable, and not calculable, respectively.

Disclosure: For full disclosures of the study authors, visit ash.confex.com.

2022 ASH Annual Meeting and Exposition

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