MHRA reviews avacopan after trial data concerns
The MHRA has opened a review into avacopan, a medicine used in some rare autoimmune illnesses. According to the regulator's notice on GOV.UK, the issue is not a routine paperwork update. New information has raised questions about whether the main clinical study behind the medicine's UK approval can be fully relied on. This is a good moment to slow the story down. When a regulator reviews a medicine, it does not automatically mean the drug has been withdrawn or that patients have done anything wrong. It means the evidence is being checked again, because medicines are licensed on proof as well as promise.
Avacopan, sold as Avacopan Vifor and previously known as Tavneos, is used alongside rituximab or cyclophosphamide. It is licensed for adults with severe, active granulomatosis with polyangiitis and microscopic polyangiitis, often shortened to GPA and MPA. These are rare diseases in which the immune system attacks small blood vessels. For patients and families, that detail matters. This is treatment for serious illness, not something taken for a short-lived problem. That is why any question around the evidence can feel frightening, even before the regulator reaches a final view.
The MHRA says the review was triggered by concerns about the integrity and reliability of data from the pivotal study that supported avacopan's licence. In plain English, the agency is asking whether the trial results that mattered most at the approval stage can still be trusted in the same way. What often gets lost in headlines is the difference between a safety scare and an evidence problem. A question about trial integrity is not the same as proof that a medicine does not work. It is serious for a different reason: if the underlying data cannot be trusted, the claims made for the treatment may need to be reassessed.
The review is being carried out under section 68 of the Human Medicines Regulations 2012. That legal route gives the MHRA the power to revoke, change or suspend a UK marketing authorisation if the application, or the material supplied with it, is wrong, or no longer supports a favourable balance between benefits and risks. A marketing authorisation is the official permission for a medicine to be sold for a particular use. **What this means in practice:** the regulator is checking whether avacopan's current licence still stands up when the evidence is looked at again.
For now, the existing safety advice remains in place. The product information still says patients should be monitored for liver function, white blood cell counts and serious infections. The MHRA is also reminding healthcare professionals to weigh the possible benefits and risks carefully for each individual patient while the review continues. **What this means for patients:** do not stop treatment on your own. The regulator's advice is to speak to your healthcare professional before making any change, because suddenly stopping a medicine used in severe autoimmune disease can bring its own risks.
The MHRA says it will publish the outcome of the review when it is complete, including any updated advice for doctors and patients. Until then, this story is about checking the evidence, not jumping to conclusions. If you or someone you care for is taking avacopan, the most useful next step is a calm one: stay in touch with the clinical team, follow the monitoring advice already in place, and report any suspected side effects through the MHRA Yellow Card scheme. For the rest of us, this is a reminder of how drug regulation is supposed to work when doubts appear: pause, test the evidence again, and keep patient safety first.