Waving off recent PhII flop, Biogen trumpets early positive Alzheimer's data for anti-tau antisense
Even as Biogen execs scrambled to defend Aduhelm and paint a rosy future the drug promises to unleash, R&D chief Al Sandrock reassured analysts during a recent earnings call that his team had more Alzheimer’s tricks.
In particular, he emphasized his belief in tau as a potential target — even though gosuranemab, the lead anti-tau antibody, had just failed a Phase II study.
“Whereas we have discontinued the BIIB092 program, we are continuing the development of BIIB080, our antisense oligonucleotide, which aims to reduce the production of all forms of tau both intra and extracellular,” he said.
Now, the drug has decent initial results to report, albeit on a biomarker that’s yet to be conclusively linked to cognitive benefit.
In a Phase Ib placebo-controlled study designed to test multiple ascending doses, Biogen said BIIB080 (also known as IONIS-MAPTRx) met the primary objective of safety and tolerability among patients with mild Alzheimer’s disease.
Furthermore, investigators observed dose-dependent decreases in the concentration of tau in the cerebrospinal fluid over the three-month treatment period, which persisted during the six-month post-treatment followup.
In patients receiving BIIB080, there were dose-dependent decreases in the concentration of total-tau in CSF eight weeks post-last dose (Day 141) with a mean percentage reduction of 30 percent, 40 percent and 49 percent in the low, medium and high dose groups treated every four-weeks, respectively, and 42 percent in the group treated every 12 weeks.
In total, 46 patients received the full regimen, although three withdrew before the post-treatment period was up.
Although tau has widely been considered the next most promising target after beta amyloid, no drugmaker has been able to prove it as such in clinical trials. On the contrary, other Big Pharma players have conceded failures and scrapped programs.
Biogen, though, was clearly willing to take another gamble, signing on to Ionis’ effort as early as 2017 and paying $45 million in cash two years later to outright license BIIB080.
And as the company has learned with Aduhelm, the FDA is more than willing to approve an Alzheimer’s drug based on a biomarker, no matter how controversial, on a hodgepodge of mixed clinical evidence. The amyloid precedent, which regulators have signaled could apply to other developers, could well have implications for tau too.
Frank Bennett, Ionis’ CSO and franchise leader for neurological programs, went as far as to bet on tau as a “root cause” of Alzheimer’s.
“Biogen is encouraged by the results of this trial, and we look forward to our continued research in future clinical studies with this promising investigational asset,” Sandrock said in a statement.