Biogen takes up option to co-develop Eisai AD drug

Biogen and Eisai have expanded their existing collaboration agreement to develop and commercialise investigational therapies for Alzheimer’s Disease.

Eisai has taken up its option to co-develop and co-promote aducanumab, Biogen's investigational anti-amyloid beta antibody for AD patients.

According to the parties, the expanded agreement leverages each company's geographic strengths for commercialisation and also adjusts the respective share of profits from potential sales of the drug.

Biogen will receive 55 percent of the potential profits in the US and 68.5 percent of the potential profits in Europe, while Eisai will receive 80 percent of the potential profits in Japan and Asia (excluding China and South Korea). The companies will have a 50:50 co-promotion split of potential profits in the rest of the world.

The US biotech will continue to lead the ongoing Phase III development of aducanumab and will remain solely responsible for all development costs for the drug until April 2018, after which point Eisai will reimburse Biogen for 15 percent of expenses from April 2018 through December 2018, and 45 percent from January 2019 onwards.

The companies will continue to jointly develop elenbecestat (E2609), a beta amyloid cleaving enzyme (BACE) inhibitor, and BAN2401, while the firm also announced an agreement to co-promote Biogen's multiple sclerosis treatments, Avonex (interferon beta-1a), Tysabri (natalizumab) and Tecfidera (dimethyl fumarate) in Japan to certain accounts.

"Through this new agreement, we believe we have improved our ability to maximize the value of aducanumab and expand the potential reach of our industry-leading multiple sclerosis portfolio," said Michel Vounatsos, Biogen’s chief executive. "The ongoing collaboration between Biogen and Eisai leverages our respective expertise and strengths in our efforts to bring new treatments to patients and families affected by Alzheimer's disease."