GSK hails survival data with revived myeloma drug Blenrep
Bone marrow aspirate showing the histologic correlate of multiple myeloma under the microscope, H&E stain
GSK's drive to resurrect its multiple myeloma therapy Blenrep has continued with new data from the DREAMM-7 trial showing an increase in overall survival (OS) with the drug had reached statistical significance.
The new data from the study shows that Blenrep (belantamab mafodotin) was more effective at extending OS than Genmab and Johnson & Johnson's anti-CD37 therapy Darzalex (daratumumab) – both given on top of Takeda's Velcade (bortezomib) plus dexamethasone (BorDex) – when used as second-line therapy for multiple myeloma.
GSK isn't revealing the size of the OS improvement yet – it has promised to do so at the American Society for Haematology (ASH) conference in December – but confirmed this morning that it plans to use the data to support its regulatory filings for Blenrep.
At this year's ASCO cancer congress in February, earlier results from DREAMM-7 revealed a 43% trend to improved OS compared to Darzalex, as well as a significant 59% gain in progression-free survival (PFS).
Blenrep won accelerated FDA approval in 2020 as a fourth-line or later treatment for multiple myeloma, becoming the first BCMA-directed therapy to reach the market.
It was, however, withdrawn from sale after the failure of the DREAMM-3 study in 2020 to show an improvement in PFS or OS when used as a third-line or later treatment. That trial was intended to confirm the accelerated approval, as well as to help move the drug into earlier-line use.
In a statement, GSK's global head of oncology R&D, Hesham Abdullah, said the OS results "underscore the potential for this Blenrep combination to extend the lives of patients with relapsed/refractory multiple myeloma." He added: "This is a statistically significant and clinically meaningful advancement for patients and potentially transformative for treatment."
In tandem with the ongoing marketing applications for Blenrep as a second-line therapy for the blood cancer – filed in the US, EU, Japan, the UK, Canada, and Switzerland to date, with a Chinese submission imminent – GSK also said it expects to start a pivotal study in newly diagnosed, transplant-ineligible multiple myeloma patients by the end of this year.
Blenrep is still available in some ex-US markets and made modest sales of £3 million ($3.8 million) in the third quarter, a far cry from GSK's previous hopes of turning the drug into a £3 billion blockbuster.
The company is hoping to restart the drug's rollout in the second half of 2025, although the jury is out on its prospects now, as other BCMA-directed drugs are now available, including a pair of BCMAxCD3 bispecifics: Johnson &Johnson's Tecvayli (teclistamab) and Pfizer's Elrexfio (elranatamab).
On GSK's third-quarter results call, chief commercial officer Luke Miels said there is an "increasing respect for the profile of the product," as well as "a broader understanding of some of the challenges employing bispecifics," which he said included infection risk, concomitant infusions, admission, and toxicity issues.
"We're humble about it. We're careful. We're working with the experts, but I think we are increasingly well-placed to do this product justice, subject to the FDA approving it," said Miels.
