Biopharmaceutical company GSK plc (LSE: GSK) (NYSE: GSK) announced on Monday that it has secured approval from Japan's Ministry of Health, Labour and Welfare for Blenrep (belantamab mafodotin) combinations to treat adults with relapsed or refractory multiple myeloma. The decision follows positive results from the phase III DREAMM-7 and DREAMM-8 trials.

Blenrep, an anti-BCMA antibody-drug conjugate, demonstrated superior efficacy across key endpoints, including progression-free survival (PFS) and overall survival (OS), compared to standard therapies. In DREAMM-7, Blenrep combined with bortezomib and dexamethasone (BVd) nearly tripled median PFS versus the daratumumab-based comparator. A statistically significant 42% reduction in the risk of death was also reported.

DREAMM-8 results showed the Blenrep, pomalidomide and dexamethasone (BPd) regimen delivered a significant PFS improvement over bortezomib-based therapy. Benefits extended to high-risk patient subgroups and those refractory to lenalidomide.

This marks the second major regulatory approval for Blenrep combinations, following UK authorisation in April 2025. Additional regulatory decisions are expected in 2025, including in the United States, European Union, China and Canada.

Blenrep offers a differentiated mechanism of action and manageable safety profile, with low discontinuation rates and reversible ocular side effects. The treatment is designed for broad applicability without requiring hospital-based administration.

Multiple myeloma remains a largely incurable blood cancer, with only 43% of patients in Japan surviving beyond five years. Blenrep combinations address significant unmet needs in earlier lines of therapy.