Britain’s medicines regulator suspended the use and sale of Amgen’s Tavneos for new patients after determining that unreliable data from the main supporting trial could no longer establish the drug’s effectiveness or whether its benefits outweighed its risks. The regulator plans to revoke the UK approval on March 1, 2027. Existing patients may continue treatment for six months while doctors consider alternatives, but have been advised not to stop without consulting a specialist. Tavneos is used alongside other medicines for severe autoimmune diseases that inflame small blood vessels and can damage the kidneys and lungs. The European Commission revoked its approval in August, while the FDA (U.S. drug regulator) has proposed withdrawing it over unproven effectiveness and false statements in the original application. Amgen is contesting the proposed U.S. withdrawal and has submitted more than 70 studies covering over 2,200 patients. An independent review found Tavneos matched steroid-based treatment at 26 and 52 weeks, but did not confirm superiority at 52 weeks. The FDA has linked the drug to 76 serious liver-injury cases, including eight deaths.