Daratumumab-based first-line therapy benefit multiple myeloma patients in a real-world setting: a multi-center retrospective propensity score-match study.

BACKGROUND

Adding daratumumab to initial therapy in randomized controlled trials (RCTs) for newly diagnosed multiple myeloma (MM) enhances deep remission and prolongs progression-free survival (PFS). Given the differences between trial-eligible and real-world patients, and healthcare access variability in developing countries, real-world data are essential to complement RCT evidence.

METHODS

We analyzed 761 newly diagnosed MM patients treated with (n = 177) or without (n = 584) daratumumab as first-line therapy from 2017 to 2023 across southern China. Propensity score matching (PSM) generated cohorts of 158 and 278 patients, respectively, matched for stage, cytogenetic abnormalities, and regimen type. Responses were evaluated per International Myeloma Working Group criteria, and measurable residual disease (MRD) was assessed via next-generation multiparameter flow cytometry.

RESULTS

The daratumumab group demonstrated significantly higher rates of ≥ very good partial response (85.0% vs. 61.3%; P < 0.001) and MRD negativity (73.0% vs. 51.9%; P = 0.024) at the end of induction. Additionally, 3-year PFS (75.6% vs. 55.0%, hazard ratio [HR] 0.49, 95% confidence interval [95% CI] 0.36-0.66, P < 0.001) and overall survival (OS) rates (78.3% vs. 74.4%; HR 0.56 [95% CI 0.36-0.86], P = 0.008) were superior in the daratumumab group, and these results remained consistent after PSM. Daratumumab improved PFS in patients with gain/amp(1q21) but not in those with del17p or t(4;14). Survival benefit was also observed in the addition of daratumumab to bortezomib/lenalidomide/dexamethasone combined treatment subgroup.

CONCLUSION

In real-world settings, daratumumab-based first-line therapy improved the depth of response, PFS, and OS, though not all patients benefited.