UK regulator to phase out Tavneos after finding trial data unreliable

The Medicines and Healthcare products Regulatory Agency (MHRA) in Britain has suspended the use and sale of Tavneos (Avacopan Vifor) for new patients after determining that the pivotal trial data supporting its approval were unreliable and that the drug’s benefit-risk balance no longer favored continued use. Amgen and CSL Vifor pushed back, arguing the regulator did not adequately consider the totality of evidence, including real-world studies; the companies emphasized ongoing support for existing patients and questioned the MHRA’s interpretation of the data. A six‑month window is allowed for patients already receiving Tavneos to continue treatment while doctors transition to alternatives, with a full withdrawal targeted by March 1, 2027. Tavneos was developed by ChemoCentryx, with Amgen holding U.S. rights and CSL Vifor marketing outside the U.S.; the European Commission had previously revoked its approval over unreliable trial data. Separately, the U.S. FDA has proposed withdrawing Tavneos due to concerns about effectiveness and safety, including reports of serious liver injury, intensifying global regulatory scrutiny of the drug.