Treatment refractoriness and response rates in patients with relapsed/refractory multiple myeloma: a retrospective...

Significant advancements have been made in the management of multiple myeloma (MM); however, high relapse rates continue to worsen prognosis and reduce survival for many patients. This study aims to evaluate treatment refractoriness and response rates in individuals with relapsed and/or refractory MM using real-world evidence.

A retrospective cohort study utilizing commercial registry data for 2022, included individuals with relapsed and/or refractory MM who are 18-79 years old and obtain minimum of 5 lines of therapy. Patients at least have one proteasome inhibitor (PI), an immunomodulatory drug (IMiD), and CD38-targeting monoclonal antibody (CD38 MoAB), with their last MM-related visit before October 2022. Patients were excluded if they had concurrent primary malignancies or documented death within 28 days of last line of treatment initiation. Descriptive data, including patient demographic and clinical characteristics, were summarized using continuous and categorical variables.

We identified 283 patients after applying inclusion and exclusion criteria. 35.7 % of patients have an overall response rate with median response duration of 6.3 months. Most of patients were found to be categorized in penta-refractory class (33.6 %), followed by triple-refractory (25.4 %), dual-refractory (19.4 %), and not triple-refractory classes (13.4 %). The response rate was 49.1% in dual-class refractory, 22.2 % in triple-class refractory, 44.7 % in not triple-class refractory, and 33.7 % in penta-class refractory patients.

Findings imply that substantial proportion of patients continue to show limited treatment response and treatment refractoriness even after multiple lines of therapy.