CHICAGO — GSK said its multiple myeloma drug Blenrep combined with other treatments helped reduce the risk of disease progression or death by almost 50% compared to standard of care.
The data further support the drug’s comeback story after a failed confirmatory study in 2022 resulted in Blenrep being pulled from the market.
The antibody-drug conjugate, paired with pomalidomide plus dexamethasone (PomDex), led to a statistically significant improvement in the primary goal of progression-free survival as compared to bortezomib plus PomDex, according to data presented Sunday at the American Society of Clinical Oncology’s annual meeting. The p-value was below 0.001.
The fleshed-out, late-breaking data arrive three months after the British drugmaker shared the study’s topline win in a press release. The DREAMM-8 results add to another win in DREAMM-7, a Phase 3 trial testing Blenrep in combination with other treatments.
“Now, we have two independent studies that provide consistency and replicability of treatment effect, and to me that provides the greatest evidence of the therapeutic benefit of the drug,” Hesham Abdullah, global head of oncology R&D at GSK, said in an interview with Endpoints News.
At the interim analysis, the drug did not have a statistically significant result on a key secondary endpoint of overall survival, but a “positive trend” was observed, GSK said. The hazard ratio was 0.77. After one year, about 83% of patients on the Blenrep combination regimen were still alive compared to 76% receiving the standard of care.
Both studies will be shared with regulators in the US, Japan and EU in the second half of this year, Abdullah confirmed, as GSK aims to get the ADC back on the market with a second-line approval. Analysts are already projecting Blenrep could become a multibillion-dollar drug.
The company declined to comment whether it’s going to seek accelerated or full approval.
Blenrep received an accelerated approval in 2020. Then, two years later, the company pulled the BCMA-targeting medicine after it failed a different Phase 3 study.
In the Sunday data, researchers said the 155 patients who received the Blenrep combination had not yet reached median PFS. In the standard of care combination group of 147 patients, the median PFS was 12.7 months.
“The median is probably going to be beyond 21 months,” Abdullah said. “The payload causes this immunogenic cell death, and that’s why you see this lengthy duration of response and durability because there’s an immune response that’s taking place.”
The complete response rate was 31% for the Blenrep combination versus 14% for the other arm.
The study looked at patients with relapsed/refractory forms of the blood cancer.
More patients had grade 3 or 4 adverse events in the Blenrep combination arm, but when factoring in the amount of time on treatment, the number of patients reporting side effects was similar between the two arms, according to comments made by Suzanne Trudel, trial investigator and clinician scientist at the University Health Network Toronto’s Princess Margaret Cancer Centre, during a press briefing.
In recent years, there has been a wave of new treatment options, including cell therapies and bispecifics for multiple myeloma patients, though physicians say there is still demand for certain patient populations.
“There is an unmet need for novel combination therapies in the relapsed setting, and the [Blenrep combination], based on this finding, is really meeting that need squarely,” said Oreofe Odejide, an oncologist at the Dana-Farber Cancer Institute in Boston, during the press briefing.