The U.S. Food and Drug Administration's panel of independent advisers delivered a significant setback to GSK on Thursday, voting against approval of the company's blood cancer drug Blenrep for use in combination with other treatments for multiple myeloma patients.
Advisory Panel Votes Against Combination Therapies
The panel voted 5-3 against approving Blenrep in combination with bortezomib and dexamethasone for adult patients with relapsed or refractory multiple myeloma who have undergone at least one prior therapy. In a more decisive rejection, the advisers voted 7-1 against approving Blenrep in combination with pomalidomide and dexamethasone.
The panel cited concerns that the overall benefit-risk profile of the treatment was not favorable for the proposed patient population at the suggested dosage, particularly for the pomalidomide combination.
FDA Raises Safety and Efficacy Concerns
The FDA had previously expressed reservations about Blenrep's approval in briefing documents released on Tuesday. The agency stated that the benefit-risk profile of Blenrep remains unclear, citing specific concerns about safety, tolerability and appropriate dosages.
These concerns reflect ongoing challenges in establishing the optimal use of Blenrep, which targets a patient population with limited treatment options.
Treatment Landscape for Multiple Myeloma
Multiple myeloma represents the third most common type of blood cancer and is generally considered treatable but not curable. The proposed combination therapies would have paired Blenrep with established cancer treatments.
Bortezomib, marketed by Johnson & Johnson as Velcade, and pomalidomide, sold by Bristol Myers Squibb as Pomalyst, are established cancer therapies in the multiple myeloma treatment arsenal. Dexamethasone is a widely used generic steroid drug commonly incorporated into cancer treatment regimens.
Market Impact
Following the advisory panel's negative votes, GSK shares fell approximately 5%, reflecting investor concerns about the commercial prospects for Blenrep in combination therapy settings. The advisory panel's recommendations, while not binding, typically carry significant weight in FDA decision-making processes.
