(Reuters: Biogen, NASDAQ:), announced on Tuesday that Michel Vounatsos, its chief executive officer at Biogen, will be leaving. Biogen also said it plans to reduce the sales of controversial Alzheimer’s medicine Aduhelm.

These are the developments and events since the controversial drug’s approval in June last year.

2007. 2007: Biogen was granted exclusive rights to aducanumab by Neurimmune Therapeutics, a spin-off of the University of Zurich. (https://

March 14, 2014: Eisai Co. Ltd (OTC:) agrees with Biogen for Alzheimer’s treatment. The Tokyo-based firm has the option to create and market aducanumab together. (https://

March 15, 2015: Biogen published interim data from its small clinical study. It showed that the brain-destroying Amyloid plaque was reduced and that there had been a slowing of clinical decline in mild patients. (https://reut.rs/3g1HHHM)

July 2015: Biogen failed to slow down mental decline by using 6 mg of aducanumab in a trial. It hoped that this dose would not cause brain swelling as seen with higher doses. (https://reut.rs/37xO1Gx)

September 2015: Biogen began testing aducanumab with people suffering from early Alzheimer’s in two late-stage, global studies called ENGAGE or EMERGE. (https://bwnews.pr/34IyKhd)

March 2019: Aducanamab is deemed unlikely to succeed by an impartial committee overseeing its extensive trials. Biogen stopped the study and suffered a $18 billion loss in market value. (https://reut.rs/3cax98b)

October 2019: Biogen revived plans for U.S. approbation after an analysis of two studies that were deemed obsolete showed the drug could slow down Alzheimer’s disease progression. (https://reut.rs/3pgD8gZ)

July 20, 2020: Biogen has submitted a biologics license application (Biologics License Application) to the U.S. FDA. This was in order for the FDA approval of aducanumab. (https://

November 2020: FDA staff stated that Biogen provided “exceptionally convincing” evidence that aducanumab was effective in documents published before a meeting with outside experts to decide whether or not to approve it. (https://reut.rs/3ujL4Cj)

November 2020: A panel of FDA outside advisors disagreed with FDA staff. They voted in favor of aducanumab not being able to slow down the progression of the disease. (https://reut.rs/3rd58nN)

June 20, 2021: Aduhelm was approved by the U.S. Health regulator. Aduhelm is a brand name for aducanumab. It claims that the decrease in amyloid plaque will likely slow down the pace of cognitive decline among Alzheimer’s patients. To facilitate the change, the agency turned to an expedited pathway to quickly bring promising drugs on to the market.

June 20, 2021: Biogen has priced the drug for an average person of average weight at $56,000 annually

June 2021: FDA has released documents detailing disagreements in the agency’s decision to approve the drug. Protest was expressed by at least three of the members of a group that included outside advisors.

July 20, 2021 FDA reversed its original broad decision regarding Aduhelm’s restriction of the drug’s use for patients with mild cognitive impairment and mild dementia stages of Alzheimer’s. It demanded an independent federal investigation into Biogen’s interactions.

July 2021: Biogen reported second quarter sales of $2 million from Aduhelm. A large chunk of the revenue came from inventory that was not being administered yet to patients, according to Biogen.

August – September 2021: U.S. lawmakers opened an investigation regarding the expedited approval and sought documents from FDA about the issue.

October 20, 2021: Aduhelm had lower sales than anticipated of $300,000. This was because doctors withheld the use of Aduhelm.

December 20, 2021: Aduhelm was rejected by the European Medicines Agency. The agency stated that the relationship between Aduhelm’s amyloid beta reduction and clinical improvements in the disease could not be established.

December 20, 2021: A reduction of approximately half the US price for the drug to $28,200.

January 2022: U.S. Medicare has announced that Aduhelm will be covered only by patients who have been enrolled in a clinical study. This restricts access to the drug.

February 2022: Biogen began to be investigated by both the Federal Trade Commission and Securities and Exchange Commission.

March 2022: Tokyo’s partner Eisai gives up its right to Aduhelm profit share and reduces their role to that of a royalty.

March 20, 2022: Biogen released data from long-term research in the less-known Journal of Prevention of Alzheimer’s Disease.

April 2022: Aduhelm was covered by its last policy of coverage, the Centers for Medicare/Medical Services.

April 2022: Biogen stated that it is withdrawing the European marketing request for the drug because the European regulator was not convinced of its effectiveness.

May 20, 2022: Biogen announced that Michel Vounatsos, Chief Executive Officer of Biogen, will retire after the appointment of a new chief executive officer. It also stated it intends to eliminate “substantially”, any commercial infrastructure related Aduhelm.