Tavneos Withdrawal Threatens Rare Disease Patients as Amgen Fights EU Decision

Amgen's Tavneos faces mounting pressure in Europe after European regulators published detailed findings supporting their decision to revoke its marketing authorization. The European Commission formally confirmed last week that Tavneos would be withdrawn from the EU market, following a June recommendation from the European Medicines Agency's Committee for Medicinal Products for Human Use (CHMP).

Tavneos was originally developed by ChemoCentryx to treat ANCA-associated vasculitis, a serious autoimmune disorder affecting blood vessels throughout the body. Amgen acquired ChemoCentryx in 2022 for $3.7 billion, inheriting both the drug's commercial prospects and the growing regulatory difficulties now threatening its future.

The CHMP's published documents allege that the pivotal phase 3 Advocate study, which secured Tavneos its original approvals, contained 'serious breaches to good clinical practice principles in the handling of primary endpoint data.' Regulators specifically allege that study sponsor personnel accessed unblinded efficacy data after an initial database lock, and then re-adjudicated nine patients based on knowledge of treatment outcomes.

Amgen pushed back firmly, stating it disagreed with the EMA's decision and was 'deeply concerned about the impact this decision may have on rare disease patients.' The company argued that the EMA's interpretation 'fails to appropriately recognize the totality of evidence supporting the effectiveness and favorable benefit-risk profile of Tavneos,' citing real-world studies and secondary endpoint findings.