Biogen aims to file with the Food and Drug Administration for regulatory approval of aducanumab, an antibody under investigation for Alzheimer’s disease, in 2020 following largely positive results of a secondary analysis of two failed phase 3 trials, ENGAGE and EMERGE, the Oct. 22.
Biogen’s plans reverse its March 21, 2019, decision with codeveloper Eisai to discontinue work on the drug after afutility analysis of the trials determined aducanumab was unlikely to yield significant benefit. Biogen announced the plan to file a biologic drug application following a new analysis of additional data that became available after the data lock on the futility analysis. But while primary and secondary endpoints were nearly all positive for EMERGE in the secondary analysis of the larger dataset, the same could not be said for the twin trial, ENGAGE, which had negative results for most of its endpoints. However, Biogen said that “results from a subset of patients in the phase 3 ENGAGE study who received sufficient exposure to high-dose aducanumab support the findings from EMERGE.”
Both the Alzheimer’s Association and researchers interpreted the announcement with a measured tone, saying it offered a hopeful sign for a field continually stymied in its quest for an effective treatment. More than 100 clinical trials have failed over the last 20 years.
Paul Aisen, MD, a consultant for Biogen and director of the Alzheimer’s Therapeutic Research Institute at the University of Southern California, Los Angeles, was similarly measured.
“There is an enormous amount of data here and they will be very challenging to interpret, especially since both trials were stopped in a futility analysis,” he said in an interview. “We’re now interpreting data that continue to be collected after the initial data lock. But I do believe there is evidence that supports the amyloid hypothesis and the development of aducanumab.”
A deep data dive is in order before the field completely embraces aducanumab’s advancement, agreed Michael Wolfe, PhD, the Mathias P. Mertes Professor of Medicinal Chemistry at the University of Kansas, Lawrence.
Still to be considered is whether aducanumab could confer enough benefits to be worth monthly, potentially lifelong, infusions of a pricey medication that still won’t stop disease progression.
“Whether the clinical impact will be worth the anticipated cost remains to be seen,” Richard J. Caselli, MD, said in an interview. “This is likely to be a very expensive treatment for a subgroup of individuals with the hope of slowing decline, but – unless there is a huge upside surprise in data yet to be released – it is not going to halt progression and will certainly increase the cost of care dramatically.”
Dr. Edelmayer said the Alzheimer’s Association has raised the issue of access and cost with Biogen.
“We have had many discussions about their capacity to roll this out,” if aducanumab is approved, she said. “Those who were in the studies will be the first recipients. But Biogen is making plans to move this into the general population if approved, to all patients who meet the diagnostic criteria.”
“There is precedent out there when it comes to doing infusion medicines, and those centers are part of the planning process. In terms of pricing, this is a problem we would be happy to see, because it would mean that we have a treatment. But we’ll cross that bridge when we come to it.”