7564 Background: In combination with conventional doublet and triplet therapy, isatuximab (Isa) provides significant benefit to patients (pts) across the multiple myeloma (MM) spectrum. Subcutaneous (SC) administration of Isa could be a more convenient option for pts and caregivers. The Phase (Ph)3 IRAKLIA trial in relapsed/refractory MM (RRMM) pts demonstrated non-inferiority in efficacy and pharmacokinetics of Isa SC delivered via a wearable on-body injector (OBI) in combination with pomalidomide and dexamethasone (Pd) vs Isa IV Pd. The Ph2 IZALCO study (NCT05704049) also showed efficacy and safety of Isa SC plus carfilzomib and dexamethasone (Kd), either by manual or OBI injections, in RRMM pts. Following exposure to both methods, pts showed higher preference for OBI vs manual SC injection. Here we present updated efficacy and safety results from IZALCO. Methods: Isa SC 1400 mg was given weekly in Cycle (C)1 then biweekly. In Part 1, pts received Isa injected SC manually. In Part 2, pts were randomized to Isa administered SC via OBI (Isa SC OBI; C1-C3) followed by manual SC injection (C4-C6), or to manual SC injection (C1-C3) followed by Isa SC OBI (C4-C6). Starting at C7, pts could choose either treatment method. All pts were treated with carfilzomib (20 mg/m 2 on Day D1-2 then 56 mg/m 2 on D8-9, 15-16 at C1, then D1-2, 8-9, and 15-16) and dexamethasone (20 mg on D1-2, 8-9, 15-16, and 22-23). Results: A total of 74 RRMM pts were enrolled (8 in Part 1; 66 in the randomized cohort, Part 2). At the data cut-off of November 10, 2025, 59 pts remained on study. At study entry, pts had median age of 65 (44-85) years, median weight of 75.9 (40.0-129.0) kg, and median of 1 prior line of therapy (1-5), and 56.8% had ISS stage I. The median duration of Isa SC OBI administration was 12 mins and manual SC injection was 6 mins. None of the Isa SC injections, manual or OBI, were interrupted. Median time to best response was 5.3 months (mos) (95% CI: 3.25-6.24). At median follow-up of 21.9 mos, median PFS was not reached (NR) (95% CI: 16.23-NR). PFS at 18 mos was 61.5% (95% CI: 48.7–72.0). OS at 18 mos was 80.8% (95% CI: 69.8-88.2); median OS was not reached (95% CI: NR-NR). Overall, grade (G) ≥3 TEAEs occurred in 66.2%, and serious TEAEs in 51.4% pts. Infusion reaction (IR) on C1D1 occurred in 2 pts (2.7%) with manual SC injections; no IRs occurred with OBI. Six (8.1%) pts had 13 injection-site reactions (ISR), all G1, in 2425 (0.54%) manual or OBI injections. Only 1 ISR was deemed related to OBI. Pt satisfaction with injection method remained consistently high with Isa SC OBI up to C25D15. Conclusions: Updated results of the IZALCO study continue to show the efficacy and safety of Isa SC plus Kd delivered either by manual injection or Isa SC OBI, while demonstrating high pt satisfaction and preference for Isa SC OBI. These findings are consistent with those reported in the Ph3 IKEMA study (Isa IV plus Kd). Clinical trial information: NCT05704049 .
Capra et al. (Thu,) studied this question.