The primary and prespecified updated analyses of ICARIA-MM (clinicaltrial gov. Identifier: NCT02990338) demonstrated improved progression-free survival (PFS) and a benefit in overall survival (OS) was reported with the addition of isatuximab, an anti-CD38 monoclonal antibody, to pomalidomide-dexamethasone (Pd) in patients with relapsed/refractory multiple myeloma. Here, we report the final OS analysis. This multicenter, randomized, open-label, phase III study included patients who had received and failed ≥2 previous therapies, including lenalidomide and a proteasome inhibitor. Between January 10, 2017, and February 2, 2018, 307 patients were randomized (1:1) to isatuximab-pomalidomide-dexamethasone (Isa-Pd; N=154) or Pd (N=153), stratified based on age (<75 vs. ≥75 years) and number of previous lines of therapy (2-3 vs. >3). At data cutoff for the final OS analysis after 220 OS events (January 27, 2022), median follow-up duration was 52.4 months. Median OS was 24.6 months (95% confidence interval [CI]: 20.3-31.3) with Isa-Pd and 17.7 months (95% CI: 14.4- 26.2) with Pd (hazard ratio=0.78; 95% CI: 0.59-1.02; 1-sided P=0.0319). Despite subsequent daratumumab use in the Pd group and its potential benefit on PFS in the first subsequent therapy line, median PFS2 was significantly longer with Isa-Pd versus Pd (17.5 vs. 12.9 months; log-rank 1-sided P=0.0091). In this analysis, Isa-Pd continued to be efficacious and well tolerated after follow-up of approximately 52 months, contributing to a clinically meaningful, 6.9-month improvement in median OS in patients with relapsed/refractory multiple myeloma.

• MeSH
• Survival Analysis MeSH
• Drug Resistance, Neoplasm MeSH
• Dexamethasone * administration & dosage   MeSH
• Adult MeSH
• Antibodies, Monoclonal, Humanized * administration & dosage   therapeutic use   MeSH
• Middle Aged MeSH
• Humans MeSH
• Multiple Myeloma * drug therapy   mortality   pathology   MeSH
• Antineoplastic Combined Chemotherapy Protocols * therapeutic use   adverse effects   MeSH
• Recurrence MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Thalidomide * analogs & derivatives   administration & dosage   MeSH
• Treatment Outcome MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Clinical Trial, Phase III MeSH
• Multicenter Study MeSH
• Research Support, Non-U.S. Gov't MeSH
• Randomized Controlled Trial MeSH
• Names of Substances
• Dexamethasone * MeSH
• Antibodies, Monoclonal, Humanized * MeSH
• isatuximab MeSH Browser
• pomalidomide MeSH Browser
• Thalidomide * MeSH

BACKGROUND: Given the incurable nature of multiple myeloma (MM), efforts are made to improve the efficacy of anti-CD38 monoclonal antibodies via combinations with other potentially synergistic therapies. This Phase 1/2 trial (NCT03194867) was designed to determine whether cemiplimab (anti-PD-1) enhances the anti-myeloma activity of isatuximab (anti-CD38) in patients with relapsed and refractory multiple myeloma (RRMM), to confirm the feasibility of the combination, determine its efficacy, and further evaluate its safety. METHODS: Patients received isatuximab 10 mg/kg once weekly for 4 weeks followed by every 2 weeks (Isa), or isatuximab 10 mg/kg plus cemiplimab 250 mg every 2 (Isa + CemiQ2W) or every 4 weeks (Isa + CemiQ4W). RESULTS: Overall, 106 patients with RRMM treated with a median of 4 prior lines were included; 25.5% had high-risk cytogenetics, 63.2% were refractory to proteasome inhibitors and immunomodulatory agents, 26.4% were previously exposed to daratumumab, and 84.0% were refractory to their last treatment line. There were no major changes in the safety or pharmacokinetic profile of isatuximab with the addition of cemiplimab. As assessed by investigators, four patients (11.8%) in the Isa arm, nine patients (25.0%) in the Isa + CemiQ2W arm, and eight patients (22.2%) in the Isa + CemiQ4W arm were responders. Though response rates were numerically higher in cemiplimab-containing arms, differences were not statistically significant and did not translate to improved progression-free or overall survival after a median follow-up of 9.99 months. CONCLUSION: Our results suggest a marginal benefit by adding cemiplimab to isatuximab, despite demonstration of target engagement, without additional observed safety issues.

• MeSH
• Dexamethasone therapeutic use   MeSH
• Antibodies, Monoclonal, Humanized adverse effects   MeSH
• Humans MeSH
• Multiple Myeloma * drug therapy   MeSH
• Antineoplastic Agents * therapeutic use   MeSH
• Antineoplastic Combined Chemotherapy Protocols adverse effects   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Clinical Trial, Phase I MeSH
• Clinical Trial, Phase II MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• cemiplimab MeSH Browser
• Dexamethasone MeSH
• Antibodies, Monoclonal, Humanized MeSH
• isatuximab MeSH Browser
• Antineoplastic Agents * MeSH

CD38 is a transmembrane glycoprotein that functions both as a receptor and an ectoenzyme, playing key roles in the regulation of calcium signaling and migration of immune cells to tumor microenvironments. High expression on multiple myeloma (MM) cells and limited expression on normal cells makes CD38 an ideal target for the treatment of MM patients. Two monoclonal antibodies directed at CD38, isatuximab and daratumumab, are available for use in patients with relapsed and/or refractory MM (RRMM); daratumumab is also approved in newly diagnosed MM and light-chain amyloidosis. Clinical experience has shown that anti-CD38 antibody therapy is transforming treatment of MM owing to its anti-myeloma efficacy and manageable safety profile. Isatuximab and daratumumab possess similarities and differences in their mechanisms of action, likely imparted by their binding to distinct, non-overlapping epitopes on the CD38 molecule. In this review, we present the mechanistic properties of these two antibodies and outline available evidence on their abilities to induce adaptive immune responses and modulate the bone marrow niche in MM. Further, we discuss differences in regulatory labeling between these two agents and analyze recent key clinical trial results, including evidence in patients with underlying renal impairment and other poor prognostic factors. Finally, we describe the limited existing evidence for the use of isatuximab or daratumumab after disease progression on prior anti-CD38 mono- or combination therapy, highlighting the need for additional clinical evaluations to define optimal anti-CD38 antibody therapy selection and sequencing in RRMM.

• Keywords
• CD38, Monoclonal antibody, Myeloma, Therapy,
• MeSH
• ADP-ribosyl Cyclase 1 MeSH
• Clinical Trials as Topic MeSH
• Humans MeSH
• Multiple Myeloma * therapy   MeSH
• Tumor Microenvironment MeSH
• Antineoplastic Agents, Immunological * therapeutic use   MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• ADP-ribosyl Cyclase 1 MeSH
• Antineoplastic Agents, Immunological * MeSH