After a tough pre-pandemic rout that saw it slash staff, steer around a cash crunch and face a bitter setback in the clinic, Selecta Biosciences is bouncing back with a major new biobucks pact with Japan’s Takeda.
The drug, maribavir, beat standard of care in transplant recipients with refractory cytomegalovirus (CMV) infection in an open-label phase 3 clinical trial. With the study also linking maribavir to fewer treatment-related toxicities such as low white blood cell counts and acute kidney injury, Takeda went into the advisory committee meeting holding a strong hand.
Takeda was rewarded with unanimous votes in favor of maribavir on the two key questions. All of the experts agreed the overall benefit-risk assessment of maribavir is favorable, regardless of whether a patient is resistant to the existing treatment options.
“Overall, the data are very persuasive in support of approval,” Nancy Bridges, M.D., transplantation branch chief of the National Institute of Allergy and Infectious Diseases, said at the committee meeting.
The unanimous votes suggest Takeda is on track to win FDA approval for maribavir. However, the experts also identified concerns with the design of the clinical trial, including the patient population and the open-label nature of the study.
Arthur Flatau, M.D., the patient representative, and Lauren Lee, M.D., bone marrow transplant medical director at Brooke Army Medical Center, both flagged the lack of data in children as a gap in the evidence that needs to be addressed. Bridges identified another shortcoming of the composition of the study population.
“The study participants were overwhelmingly white,” Bridges said. “We know that CMV serum positivity has a much higher prevalence among African Americans. So, within the context that I do hope that this drug is approved, I would like to see some requests to the company to gather data about efficacy in African Americans, because I don’t think we have any data really on that.”
Lee also expressed an interest in seeing how maribavir would fare in a blinded, controlled clinical trial. Maribavir, back when it was owned by ViroPharma, failed a phase 3 placebo-controlled clinical trial in 2009. Takeda, which acquired maribavir through its takeover of Shire, defended its decision to run an open-label study on the grounds that the drug causes taste disturbance that affects blinding.