Two US congressional committees have accused the country’s Food and Drug Administration of inappropriately collaborating with Biogen before approving the company’s Alzheimer’s drug.

A joint report by the House committees on Oversight and Reform, and Energy and Commerce accused the FDA of granting Aduhelm, Biogen’s Alzheimer’s drug, accelerated approval in 2021 despite an internal advisory committee’s refusal to issue a favourable recommendation, and concerns about the drug’s inconsistent clinical data.

The report published on Thursday also accused the regulator of failing to record critical meetings with Biogen and of improperly collaborating with the company on a joint briefing that was later presented to an important FDA advisory committee.