Belantamab Mafodotin Regimen Indicates Safety, Improved OS in Patients Treated With Multiple Myeloma

Results from an interim analysis of the ongoing DREAMM-8 phase 3 trial (NCT04484623) examining belantamab mafodotin (Blenrep; GlaxoSmithKline) in combination with pomalidomide plus dexamethasone (PomDex) showed that the trial met its primary endpoint of progression-free survival (PFS) and was unblinded early based on a recommendation from an independent data monitoring committee. The belantamab mafodotin regimen was compared with a standard of care treatment, bortezomib plus PomDex, in the second-line and later for patients with relapsed or refractory (R/R) multiple myeloma.¹

Belantamab mafodotin is an antibody-drug conjugate that consists of a humanized B-cell maturation antigen monoclonal antibody conjugated to the cytotoxic agent auristatin F through a non-cleavable linker. The multicenter, open-label, randomized phase 3 DREAMM-8 trial evaluated the efficacy and safety of belantamab mafodotin in combination with PomDex and compared it with the combination of bortezomib and PomDex in patients with R/R MM.¹

A total of 302 patients who are aged 18 years and older and who previously received at least 1 line of therapy—including a lenalidomide-based regimen—with a documented disease progression either during or after their most recent therapy were randomly assigned to receive either the belantamab mafodotin regimen or bortezomib regimen. Further, the primary end point was PFS, and the secondary end points were overall survival (OS), overall response rate (ORR), duration of response, minimal residual disease (MRD) negativity as assessed by next-generation sequencing, safety, as well as quality of life and patient-reported outcomes.^1,2

According to the analysis results, the belantamab mafodotin combination regimen had extended the time to disease progression or death compared to the standard of care combination therapy. Further, there was a positive OS trend that favored the belantamab mafodotin regimen; however, the trial is currently still ongoing to follow up on the results shown in OS. In addition, both the safety and tolerability profiles of belantamab mafodotin plus PomDex were consistent with the previously established safety profiles of the individual agents.¹

“The results seen in both DREAMM-7 and DREAMM-8 provide strong clinical evidence of the robust efficacy shown with belantamab mafodotin in use with standard of care combinations. We now look forward to discussing these data with regulators,” said Hesham Abdullah, senior vice president, global head oncology, R&D, GSK, in a press release.¹

The investigators note that DREAMM-8 is the second head-to-head phase 3 trial that assessed belantamab mafodotin as a second-line or later treatment for MM to report positive results. DREAMM-7 (NCT04246047) is another phase 3 trial that evaluated belantamab mafodotin, though this trial combined the therapy with bortezomib and dexamethasone (BorDex) and compared it with the efficacy of daratumumab and bortezomib plus dexamethasone. Similarly to DREAMM-8, the primary end point is PFS, and secondary end points include ORR, OS, duration of response, and MRD negativity, as well as complete response rate, time to response, and clinical benefit rate.^1,3

“If approved, we believe these combinations have the potential to redefine the treatment of [R/R MM] and advance the standard of care. This is exciting news for patients given the high unmet medical need for both efficacious and easily administered therapies with differing mechanisms of action,” said Abdullah in the press release.¹

References

1. GlaxoSmithKline. GSK announces positive results from DREAMM-8 phase III trial for Blenrep versus standard of care combination in relapsed/refractory multiple myeloma. News release. March 7, 2024. Accessed March 7, 2024. https://www.gsk.com/en-gb/media/press-releases/gsk-announces-positive-results-from-dreamm-8-phase-iii-trial-for-blenrep-versus-standard-of-care-combination-in-relapsedrefractory-multiple-myeloma/

2. Belantamab Mafodotin Plus Pomalidomide and Dexamethasone (Pd) Versus Bortezomib Plus Pd in Relapsed/​Refractory Multiple Myeloma (DREAMM 8).ClinicalTrials.gov identifier: NCT04484623. Updated November 2, 2023. Accessed March 7, 2024. https://clinicaltrials.gov/study/NCT04484623

3. Evaluation of Efficacy and Safety of Belantamab Mafodotin, Bortezomib and Dexamethasone Versus Daratumumab, Bortezomib and Dexamethasone in Participants With Relapsed/​Refractory Multiple Myeloma (DREAMM 7).ClinicalTrials.gov identifier: NCT04246047. Updated December 13, 2023. Accessed March 7, 2024. https://clinicaltrials.gov/study/NCT04246047