Biogen makes another Alzheimer's bet, paying Pfizer $75M for early-phase drug

Biogen has placed another bet on Alzheimer’s disease R&D, paying Pfizer $75 million upfront for an early-phase prospect. The candidate, PF-05251749, came through tests in healthy volunteers at Pfizer before getting derailed by the Big Pharma’s retreat from neuroscience R&D in 2018.

PF-05251749 is a CK1 inhibitor that moved into the clinic on the strength of evidence it can cross the blood-brain barrier and regulate circadian rhythms, thereby improving behavioral and neurological symptoms in patients with diseases including Alzheimer’s. Pfizer gathered clinical data on the drug’s safety and mechanism of action before exiting neuroscience R&D in 2018.

Biogen thinks the data generated to date support further development, leading it to pay $75 million and commit to up to $635 million in development and commercialization milestones to add the drug to its pipeline. 

In disclosing the deal, Biogen singled out sundowning in Alzheimer’s and irregular sleep wake rhythm disorder (ISWRD) in Parkinson’s disease as indications of interest. Sundowning causes about 1 in 5 Alzheimer’s patients to suffer from symptoms including confusion and anxiety later in the day. In Parkinson’s, ISWRD negatively affects nighttime sleep, leading to symptoms such as fatigue.

Biogen thinks the effect of PF-05251749 on circadian rhythms may make it an effective treatment for sundowning and ISWRD. Similar thinking underpins studies of the use of melatonin to treat the two conditions but is yet to manifest in an established pharmacological intervention.  

The willingness of Biogen to spend money to change that is further evidence of its commitment to Alzheimer’s. Late last year, Biogen paid Ionis Pharmaceuticals $45 million upfront for IONIS-MAPT Rx, a tau-targeting antisense treatment that is in phase 1 testing in patients with mild Alzheimer’s.

If Biogen gets its way, IONIS-MAPT Rx and PF-05251749 will be part of an Alzheimer’s portfolio led by a commercial product, namely aducanumab, the anti-amyloid drug that is heading to the FDA for review despite failing a phase 3 futility analysis. Biogen Chief Medical Officer Al Sandrock sees PF-05251749 as a good fit with his company’s other assets. 

“This asset is highly complementary to our existing pipeline of potential disease-modifying therapies. Many patients with Alzheimer’s and Parkinson’s suffer from debilitating sleep disorders and agitation, and we believe that the regulation of the circadian rhythm may hold promise in addressing these challenging behavioral and neurological symptoms,” Sandrock said in a statement.