Pharmacy considerations: Use of anti-CD38 monoclonal antibodies in relapsed and/or refractory multiple myeloma

OBJECTIVE

This article reviews current evidence for the approved anti-CD38 monoclonal antibodies, isatuximab and daratumumab, for the treatment of patients with relapsed and/or refractory multiple myeloma (RRMM) and the implications for pharmacists.

DATA SOURCES

We conducted a literature search on PubMed/Medline and other sources using the drug names and the terms CD38, multiple myeloma, and pharmacists.

DATA SUMMARY

Monoclonal antibodies targeting the CD38 transmembrane glycoprotein offer a promising treatment approach for patients with RRMM. Isatuximab and daratumumab bind to different epitopes on CD38. In this review, we describe the similarities and differences in their mechanism of action, regulatory labeling, and the current guidelines for isatuximab and daratumumab use in RRMM. We review the current evidence for the efficacy and safety of these agents in combination with pomalidomide or carfilzomib and dexamethasone from the landmark phase 3 clinical trials that led to their approval. We discuss key differences in the eligibility criteria between the clinical trials, and differences in dosing, administration, available formulations, and pre- and post-infusion medications for the two agents. We outline recent data from pharmacoeconomic analyses comparing the cost-effectiveness of isatuximab-based regimens with that of daratumumab-based regimens. A brief overview of other anti-CD38 agents in the pipeline for the treatment of patients with RRMM is presented.

CONCLUSIONS

Given that pharmacists play an integral role in driving cost-effective use of drugs without compromising efficacy and safety for the end user, educating pharmacists on the key differences between isatuximab and daratumumab can guide the selection of the appropriate anti-CD38 antibody.

Isatuximab: A Review of Its Use in Multiple Myeloma

Isatuximab (Sarclisa®; isatuximab-irfc in the USA) is an anti-CD38 monoclonal antibody (mAb) approved for use in the treatment of adults with multiple myeloma (MM): in combination with pomalidomide and dexamethasone for those with relapsed and refractory MM (RRMM) who have received ≥ 2 prior therapies, including lenalidomide and a proteasome inhibitor; and in combination with carfilzomib and dexamethasone for those with relapsed MM who have received ≥ 1 prior therapy. In phase III studies, the addition of isatuximab to pomalidomide and dexamethasone significantly prolonged progression-free survival (PFS) and improved the depth of tumour response in patients with RRMM, as did the addition of isatuximab to carfilzomib and dexamethasone in patients with relapsed or refractory MM. Health-related quality of life was maintained when isatuximab was combined with these other therapies. Isatuximab-based combination therapies were generally well tolerated and demonstrated a manageable safety profile with no new safety signals. Although mature overall survival data are awaited, available evidence indicates that the combinations of isatuximab with pomalidomide and dexamethasone and isatuximab with carfilzomib and dexamethasone are important additional treatment options for RRMM and relapsed MM, respectively.