FDA urges Amgen to withdraw Tavneos after alleging data manipulation by former developer

The FDA has sent a formal letter to Amgen recommending that the company pull its drug Tavneos from the market. The agency says new information shows the original approval filings from ChemoCentryx contained false statements and that study staff altered results to make the drug appear effective.

Amgen bought Tavneos in a deal worth almost $4 billion in 2022 and had said it would continue selling the product despite earlier safety and efficacy concerns. The regulator now argues that the initial analysis, which was not disclosed, contradicts the positive conclusions presented to the FDA.

Tavneos will remain available only until Amgen decides to withdraw it or the FDA commissioner orders its removal. The development adds regulatory risk for Amgen and highlights scrutiny of data integrity in drug approvals.