Ivan Cheung, SVP and global Alzheimer’s disease officer at Eisai, announced Tuesday morning that he would retire later this month following the Food and Drug Administration’s full approval of Leqembi, the treatment the company jointly developed with Biogen. 

Late last week, the FDA granted traditional approval to Leqembi in a watershed moment for Alzheimer’s care that was widely expected following accelerated approval in January and a unanimous recommendation from external advisors to the agency last month.

The drug is set to be a blockbuster that could generate billions by the end of the decade and Cheung said earlier this year that its limited launch has already been “smooth and very much on-track.”

In addition to the FDA greenlight, the Centers for Medicare and Medicaid Services announced that Leqembi would receive broader coverage under Medicare. This policy revision has been years in the making and occurred on Cheung’s watch. 

Cheung, who has been with the company since 2005, was named SVP and CEO of Eisai’s North America division in 2016 and took on the role of Alzheimer’s lead in late 2019. Beyond his duties in the brain disease space, he was also active in the oncology space and spearheaded the global launch of Lenvima through a strategic partnership with Merck.

According to a press release issued by the Japanese drugmaker, Cheung stated that he “has realized his missions” at Eisai and has a “strong desire” to pursue the next chapter of his executive career.

Eisai CEO Haruo Naito commended Cheung in a statement, noting his accomplishments shepherding Leqembi across the finish line in the U.S. as well as representing Eisai on the PhRMA Board.

“Ivan Cheung has made tremendous contributions to the realization of social good through the successful development of lecanemab, the world’s first treatment for the underlying pathology of early-stage Alzheimer’s Disease. Also, I have appreciated his efforts to give growing opportunities for various talents in various functions,” Naito stated.

Going forward, Cheung’s responsibilities will be carried out by internal senior executives, which will take place immediately in order to kickstart the transition process.

In light of Cheung’s announcement, Eisai’s stock was down by 4.3% during the Tuesday trading session.