EU Revokes Marketing Authorization for Tavneos Over Study Reliability Concerns

Tavneos' marketing authorization in the European Union has been revoked by the European Commission due to 'serious breaches' of protocol in a pivotal clinical study. The decision was based on an ongoing review that found flaws in the handling of primary endpoint data, which led to a re-adjudication of nine patients and changed the results. This manipulation was not disclosed to regulators, who felt that it compromised the reliability of the study.

The European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP) flagged safety concerns over several fatal cases of drug-induced liver injury or vanishing bile duct syndrome among patients taking Tavneos since its marketing authorization in the EU. The regulator concluded that there is no longer a demonstration of benefit outweighing the risks, particularly the serious hepatic risks.

Amgen, which acquired ChemoCentryx for $3.7 billion in 2022 and now owns Tavneos' rights, has disputed the decision and argued that the data does not support revoking marketing authorization. The company will continue to defend the drug's position in the U.S., where it faces an FDA market withdrawal request.