UK regulator opens a review and medical journal launches an investigation
Two further developments concerning avacopan — marketed as Tavneos, and in the UK as Avacopan Vifor — took place in the same week. The UK’s medicines regulator has opened its own review of the medicine, and the New England Journal of Medicine (NEJM) has begun an investigation into the trial that supported its approval.
The UK opens a separate review
On 5 June 2026 the UK’s Medicines and Healthcare products Regulatory Agency (MHRA) announced that it is reviewing the benefits and risks of avacopan. According to the agency, the review was prompted by information raising questions about the integrity and reliability of the data from the pivotal clinical study on which the licence was based. The MHRA will assess whether this affects what the study showed about how well the medicine works, and what that means for the overall benefit-risk balance.
This is a separate process from the reviews already underway elsewhere. There is no single regulator covering all countries. The European Medicines Agency (EMA) acts for the European Union and the EEA countries (Norway, Iceland and Liechtenstein); it opened its own review in January 2026. Since Brexit, the UK is regulated independently by the MHRA. Switzerland is regulated separately again, by Swissmedic. As a result, the FDA in the United States, the EMA and the MHRA are now each examining the same medicine in parallel, on their own timetables, and a decision by one authority does not automatically apply in the others.
The NEJM opens an investigation
Bloomberg reported on 5 June 2026 that the New England Journal of Medicine has opened an investigation into alleged research misconduct in the 2021 article that reported the results of the pivotal trial. This is an academic-integrity process concerning the published paper. It is separate from the regulatory reviews, although it relates to the same underlying data. The outcome — a correction, a retraction, or no change — is not yet known.
What this means for patients
These developments do not change any patient’s prescription at this time. No one should stop or alter their treatment because of this news. Anyone with questions about their own treatment should speak with their treating specialist, who is best placed to advise on their individual situation. The manufacturer has stated that it stands by the medicine, while the regulators continue their reviews.
Vasculitis International is following all of these developments and will publish further updates as each process progresses.