Biogen (BIIB) said its BLA for aducanumab, the Alzheimer’s disease candidate it is co-developing with Eisai, has been accepted for Priority Review by the FDA with a target action date of March 7, 2021—and a decision expected from the agency even earlier.

The FDA plans to hold an Advisory Committee meeting for the application on a date yet to be set. Biogen said it was told by the agency that it plans to act early on aducanumab under expedited review. Biogen added that it did not use its Priority Review voucher for the aducanumab BLA.

If approved, aducanumab would be the first therapy indicated for reducing clinical decline in people with Alzheimer’s disease, and would also be the first therapy to tie improved clinical outcomes to removing amyloid beta.

“The FDA’s acceptance of the aducanumab BLA with Priority Review is an important step in the path to potentially having a treatment that meaningfully changes the course of Alzheimer’s disease,” Biogen CEO Michel Vounatsos said in a statement. “We look forward to working with the FDA throughout the review process and thank the thousands of clinicians, patients, and caregivers who participated in our clinical trials and have accompanied us on this journey.”

That journey has included numerous twists and turns. In October 2019, Biogen surprised analysts by saying it planned to file for FDA approval of aducanumab despite halting two failed Phase III studies of the drug seven months earlier. Biogen and Eisai asserted that one of those trials, the EMERGE Study (NCT02484547) met its primary endpoint showing a significant reduction in clinical decline—a result the companies later said is supported by results from a subset of patients in the other halted Phase III study, ENGAGE (NCT02477800).

“We like the fact that BIIB earned this priority review vs. forcing one by utilizing a voucher that BIIB previously had,” Canaccord Genuity analyst Sumant Kulkarni wrote in a note to investors. “As we had [previously] surmised, we believe investors will view this ‘clean’ grant of priority review as a potential indicator of FDA’s receptivity towards the adu[canumab] BLA.”

“Significant Potential for Upside”

Kulkarni added: “As such, we continue to believe BIIB affords significant potential for upside as the fear of missing out, which remains a key tenet of our BUY thesis, becomes even more real for investorsnow.”

Investors on Friday sent shares of Biogen on NASDAQ up 9.5% in early trading Friday, to $304.02 as of 12:03 pm—up from Thursday’s closing price of $277.66.

“The stock is trading in the pre-market above $300, and we would expect it to continue moving higher as we approach the AdCom, as investors increasingly believe that the risk/reward is favorable for owning the name into this event,” Marc Goodman, managing director, neuroscience, at SVB Leerink, and colleagues, wrote in an investor note Friday.

Goodman has set a price target (PT) of $350 a share, and noted that SVB based that target on adding 50% to its $260 a share valuation for Biogen excluding aducanumab.

“With approval, our PT would add the other 50% ($90) to drive to $440, so we remain positive and Outperform on the stock,” added Goodman, who is also a senior research analyst at SVB Leerink covering neuroscience and ophthalmology.

Additional Clinical Study Predicted

However, Brian P. Skorney, CFA, Senior Research Analyst at Baird, predicted today in an investor note that since the BLA must still undergo review and an advisory committee (AdCom) meeting, “we continue to believe the ultimate recommendation will be for at least one additional clinical study.”

The meeting, Skorney wrote, will address the regulatory agency’s flexibility toward “an even lower threshold of approvability than the generationally low threshold we already have today.”

“We continue to think that the abundance of data indicates that aducanumab likely does not provide a clinical benefit, as evidenced by clear and profound reductions in the biomarker, but absence of a clinical benefit across two large studies,” Skorney added. “Given the history of the FDA Division of Neurology’s ability to provide sound critique of unsupportable applications, we believe they [sic] review will be negative but acknowledge that political pressure continues to play a clear role in everything at FDA these days.”

FDA Commissioner Stephen M. Hahn, MD, however, has maintained that the agency has risen above politics. Speaking with The New York Times in a report published today, he stated: “I have been consistent in my message internally about using data and science to make decisions.”

Long Struggle

Biogen and Eisai hope to succeed where numerous other drug developers have failed in the long struggle to create successful new drugs for Alzheimer’s disease. Only a handful of drug successes have ever reached the market, and even they have merely slowed progression of symptoms by 6 to 12 months.

2014 Cleveland Clinic study found a 99.6% failure rate of clinical trials for Alzheimer’s disease drug candidates between 2002 and 2012. That study found high attrition rates for Alzheimer’s disease treatments, with 72% of agents failing in Phase I, 92% failing in Phase II, and 98% failing in Phase III.

Eisai joined Biogen in partnering on aducanumab in 2017—10 years after Biogen (then called Biogen Idec) began developing the drug under license from its original developer, Zurich-based Neurimmune.

“We believe that aducanumab marks the beginning of a new era of potential treatments for Alzheimer’s disease that will inspire even more discovery and innovation to bring hope to those affected by this devastating disease,” Vounatsos added