Li, Chun-Rui

PURPOSE To report the results of the multicenter, open-label IRAKLIA trial (ClinicalTrials.gov identifier: NCT05405166 ) of isatuximab subcutaneous (SC) versus intravenous (IV), plus pomalidomide and dexamethasone, in relapsed/refractory multiple myeloma (MM), to our knowledge, the first phase III MM trial using an on-body injector (OBI). METHODS Patients with ≥1 prior line of therapy were randomly assigned 1:1 to Isa OBI (1,400 mg) or IV (10 mg/kg) once weekly in cycle (C)1 and then every 2 weeks, plus pomalidomide (4 mg once daily, day [D]1-21) and dexamethasone (40 mg once weekly [age ≥75: 20 mg]) and treated until progression, unacceptable toxicity, or patient request. Coprimary end points were overall response rate (ORR; noninferiority margin, 0.839) and Isa C trough (C6D1 predose; noninferiority margin, 0.8). Noninferiority of OBI versus IV was demonstrated if both coprimary end points achieved noninferiority. RESULTS IRAKLIA randomly assigned 531 patients (OBI, n=263; IV, n=268). After 12-month median follow-up, the ORR was 71.1% (OBI) and 70.5% (IV; relative risk, 1.008 [95% CI, 0.903 to 1.126]; lower CI exceeded noninferiority margin). The mean (standard deviation) C6D1 C trough was 499 (259) μg/mL (OBI) and 340 (169) μg/mL (IV). The C trough geometric mean ratio (90% CI) was 1.532 (1.316 to 1.784); lower CI exceeded noninferiority margin. Grade ≥3 treatment-emergent adverse event incidences were 81.7% (OBI) and 76.1% (IV); infusion reaction incidences were 1.5% and 25.0%. Injection site reactions occurred in 0.4% of OBI injections (all grade 1-2); 99.9% of injections completed without interruption. CONCLUSION IRAKLIA demonstrated efficacy and pharmacokinetic noninferiority between Isa OBI and IV. No unexpected safety signal was observed, with excellent local tolerability of Isa OBI. Efficacy and safety were comparable with Isa IV in ICARIA-MM, except the lower OBI infusion reaction rate. These results support potential use of the OBI, designed to improve practice efficiency.

Chimeric antigen receptor (CAR) T cell immunotherapy for the treatment of neurological autoimmune diseases is promising, but CAR T cell kinetics and immune alterations after treatment are poorly understood. Here, we performed single-cell multi-omics sequencing of paired cerebrospinal fluid (CSF) and blood samples from patients with neuromyelitis optica spectrum disorder (NMOSD) treated with anti–B cell maturation antigen (BCMA) CAR T cells. Proliferating cytotoxic-like CD8 + CAR T cell clones were identified as the main effectors in autoimmunity. Anti-BCMA CAR T cells with enhanced features of chemotaxis efficiently crossed the blood-CSF barrier, eliminated plasmablasts and plasma cells in the CSF, and suppressed neuroinflammation. The CD44-expressing early memory phenotype in infusion products was potentially associated with CAR T cell persistence in autoimmunity. Moreover, CAR T cells from patients with NMOSD displayed distinctive features of suppressed cytotoxicity compared with those from hematological malignancies. Thus, we provide mechanistic insights into CAR T cell function in patients with neurological autoimmune disease.