Biogen’sMichel Vounatsos, the Chief Executive Officer of Aduhelm is retiring. This comes as Aduhelm is struggling with Medicare’s restriction on coverage for Aduhelm in clinical trials.

Vounatsos will remain in the role of CEO until his successor is chosen. He was appointed in 2016. Vounatsos has served as CEO since 2016 when Biogen launched many flagship drugs, including Spinraza for spinal muscular atrophy, Vumerity for multiple sclerosis, and Aduhelm.

Biogen announced Tuesday that it would be looking into significantly eliminating the commercial infrastructure associated with the Alzheimer’s drug. It also plans to further reduce costs, as well as continuing the existing program of saving $500 million per year.

Aduhelm only covers patients in clinical trials. Aduhelm said that the company will not make it available for patients in treatment at the U.S.

Aduhelm is the first treatment to treat the memory-robbing disorder in almost 20 years. The company bets that it will act as a buffer against rising competition.

Aduhelm, however, has had to overcome many obstacles after it was approved by the U.S. Food and Drug Administration last June as part of an expedited approval process.

Investigations have been initiated into FDA’s decision to overrule outside advisors. Doctors have resisted prescribing Aduhelm and in April, the U.S. Medicare operator decided that Aduhelm would not be covered under its government insurance plan.

In a note, Michael Yee from Jefferies said that tough changes will be viewed by the Street as a step in the right direction to improve BIIB sentiment and longer-term spending. “The changes had been discussed previously… however the timing wasn’t necessarily anticipated this soon.”

Biogen now counts on the development of its second Alzheimer’s treatment lecanemab with Japanese company Eisai Co. Ltd.

Biogen expects to finish the rolling submission for lecanemab as part of the U.S. accelerated approval path in the second half.