The MHRA pulls a vasculitis drug over unreliable trial data

The Medicines and Healthcare products Regulatory Agency suspended the use, supply and sale of Avacopan Vifor to new patients in the United Kingdom from 1 September 2026, and said it will revoke the marketing authorisation on 1 March 2027. Patients already on the drug may continue during a six-month managed withdrawal. The medicine treats severe, active granulomatosis with polyangiitis and microscopic polyangiitis, rare autoimmune diseases that attack small blood vessels.

The reason is not a safety signal in patients. It is the evidence base. The MHRA cited concerns about “the integrity and reliability of data from the pivotal clinical study”, and concluded that the study can no longer be relied on to demonstrate the medicine’s efficacy, leaving the data insufficiently reliable to support a positive benefit-risk balance.

That is a different kind of regulatory action from a withdrawal over harm, and a harder one to undo: what has been unwound is the trial that justified the approval in the first place. For the people taking it, the decision is concrete in a way most data-integrity findings are not — a therapy they were allowed to have comes off the table over the next six months, on the ground that nobody can now show it worked.