The overall survival edge over J&J’s Darzalex will help GSK strengthen its case as it plots the market comeback of Blenrep, which was pulled after a failed confirmatory study.
GSK on Monday unveiled additional data from the Phase III DREAMM-7 study of its once-withdrawn antibody-drug conjugate Blenrep (belantamab mafodotin), demonstrating significant survival benefits in relapsed or refractory multiple myeloma.
When used as a second-line treatment, and in combination with bortezomib plus dexamethasone, Blenrep reduced the risk of death by 42% versus a comparator treatment regimen based on Johnson & Johnson’s Darzalex (daratumumab). These data were obtained at a median follow-up of 39.4 months, at which point median overall survival (OS) had not yet been reached.
GSK projected a median OS of 84 months in Blenrep-treated patients versus 51 months in those given Darzalex. Three-year OS was 74% in the Blenrep arm and 60% in the control group. According to the pharma, Blenrep’s survival benefit was apparent as early as four months after treatment initiation and remained superior over time.
Blenrep also beat Darzalex in terms of secondary endpoints, including duration of response and progression-free survival. In addition, treatment with the Blenrep combo resulted in a 2.5-fold jump in the rate of minimal residual disease—meaning having no detectable cancer cells—versus Darzalex. This effect was strongly statistically significant, with a p-value less than 0.00001, GSK noted in its announcement.
Hesham Abdullah, global head of GSK’s Oncology R&D, called these OS data “compelling” in a statement, adding that they solidify the “potential of Blenrep in combination to significantly extend the lives of patients with multiple myeloma at or after first relapse.” DREAMM-7’s findings, according to Abdullah, “could redefine the treatment of relapsed or refractory multiple myeloma.”
Monday’s readout follows an earlier data drop from DREAMM-7 in February 2024, which showed a 59% reduction in the risk of death or disease progression versus the Darzalex regimen. Last month, GSK announced that Blenrep also surpassed J&J’s therapy in terms of OS but did not provide specific data to back this claim.
In March 2024, GSK revealed that a second late-stage study, dubbed DREAMM-8, aced its primary endpoint of progression-free survival, with Blenrep significantly outperforming standard of care—bortezomib, pomalidomide and dexamethasone—in the second-line setting in multiple myeloma. The pharma did not reveal specific data at the time but announced that these findings pushed an Independent Data Monitoring Committee to recommend the early unblinding of the trial.
Together, DREAMM-7 and DREAMM-8 are helping GSK pave the way for Blenrep’s re-entry into the market after it was forced to pull the drug in November 2022 because of a failed Phase III confirmatory study. At a cancer-focused investor event in June 2024, GSK executives reiterated their confidence in Blenrep’s comeback, pointing to its “multi-blockbuster” potential and the possibility of hitting peak sales over $3 billion.
Also on Monday, GSK continued its deal-making spree with an AI partnership with U.K.-based biotech Relation Therapeutics to target osteoarthritis and fibrotic diseases, as reported by The Times. The pharma will pay $45 million upfront and pledge up to $63 million in success-based milestones. Relation will also be eligible for milestones averaging $200 million per target, according to The Times.
