FDA Proposes Withdrawal of Avacopan Due to Manipulated Data and Liver Safety Concerns

Who is this relevant for?

• Hospitals managing supply risk
• Distributors monitoring sourcing opportunities

The FDA is moving to withdraw avacopan (Tavneos) from the US market. The agency says the drug's pivotal trial data were manipulated and that postmarketing liver injuries, including eight fatal cases, raise new safety concerns.

The action follows a January request for voluntary withdrawal, which Amgen rejected. In March, the FDA warned about dozens of serious drug-induced liver injury (DILI) cases. The agency now proposes formal withdrawal based on lack of substantial evidence and untrue statements in the original application.

The ADVOCATE trial originally showed a 65.7% remission rate for avacopan versus 54.9% for prednisone. But according to the FDA, an initial analysis failed to reach significance. Unblinded study personnel at ChemoCentryx selected five avacopan patients for readjudication, changing their outcomes from "not in sustained remission" to "sustained remission." This turned a negative study into a positive one. The company did not disclose the manipulation.

Amgen stands by the drug, citing years of clinical and real-world data. The company will respond to the FDA. For hospitals and distributors, the outcome could affect treatment protocols and supply chains for ANCA-associated vasculitis.