Biotechnology company Biogen is abandoning Aduhelm, its questionable Alzheimer's drug that has floundered on the market since its scandal-plagued regulatory approval in 2021 and brow-raising pricing.

On Wednesday, the company announced it had terminated its license for Aduhelm (aducanumab) and will stop all development and commercialization activities. The rights to Aduhelm will revert back to Neurimmune, the Swiss biopharmaceutical company that discovered it.

Biogen will also end the Phase 4 clinical trial, ENVISION, that was required by the Food and Drug Administration to prove Biogen's claims that Aduhelm is effective at slowing progression of Alzheimer's in its early stages—something two Phase 3 trials failed to do with certainty.

In the announcement, Biogen noted it took a financial hit of $60 million in the fourth quarter of 2023 to close out its work on Aduhelm, which the company at one point reportedly estimated would bring in as much as $18 billion in revenue per year.

The saga

But the data never appeared to support such lofty aspirations. The drug is intended to work against the clumps of misfolded beta-amyloid protein that accumulate in the brains of people with Alzheimer's. Though a small, early clinical trial showed the drug could reduce plaques in the brains of people with Alzheimer's, it initially failed two identically designed Phase 3 trials. The trials, which collectively enrolled nearly 3,300 patients, intended to evaluate if the drug could slow the progression of Alzheimer's in its early stages.

In March 2019, the company announced that it was ending both trials after a futility analysis indicated that the drug wasn't working. But later that year, Biogen stunningly reversed course, saying that additional data had rolled in from the trials after the March announcement. A new analysis of the data from one of the two trials indicated that a subset of patients given the highest dose showed a small benefit on cognitive tests—though the patients in the other trial still saw no benefit. The data also found that 40 percent of patients given the high dose developed brain swelling.

Biogen boldly submitted its data to the FDA for approval. In November 2020, a panel of independent advisers for the FDA voted resoundingly against Aduhelm's approval. Ten of 11 committee members voted against the drug, while the remaining member voted "uncertain." After voting no, one member commented on the "incongruity" of Biogen's presentation of the drug and the actual data. "It just feels to me like the audio and the video on the TV are out of sync, and there are literally a dozen red threads that suggests concerns about the consistency of evidence—a dozen," the member said. The FDA, too, in its own statistical analysis of the data, concluded that "there is no compelling substantial evidence of treatment effect or disease slowing."