Many MindedTavneos approval under threat as FDA doubts the trial behind it
The FDA approved Tavneos on October 7, 2021, for ANCA-associated vasculitis, a rare autoimmune disease that can damage the kidneys and lungs. In April 2026 the agency sent a letter proposing to withdraw it from the US market. It cited reports of serious, sometimes fatal liver injury and a lack of "substantial evidence" that the drug works. Withdrawal is only proposed, and the drug's final fate in the US is undecided.
The pivotal trial was run by ChemoCentryx, which Amgen acquired a year after approval. Even before approval, an FDA briefing document in May 2021 said the trial design made results hard to interpret, and the advisory committee voted only narrowly to recommend approval. Participants showed slightly higher remission rates after one year. An investor lawsuit later turned up what the FDA believes is evidence that ChemoCentryx employees manipulated the trial data. Amgen disputes that and says the drug works. This summer the New England Journal of Medicine retracted the trial paper, and the EU took Tavneos off the market. The UK has said it will follow.
This is friction on the health front, and it cuts two ways. Approval is only worth something if the data behind it can be trusted, and a $220,000-a-year drug with nearly $500 million in fiscal 2025 sales shows what rests on that trust. Yet pulling it could strand patients with few alternatives. Tavneos was meant to replace or reduce steroids, and one 20-year-old patient reported gaining 40 pounds in about six weeks on them.
Watch for the FDA's decision after Amgen's 104-page filing arguing the totality of evidence supports continued availability. An independent registry study co-authored by UCSF's Eric Roberts called the drug apparently efficacious. Whether the control group reflected standard care is still debated. A proposed $69 million investor settlement also awaits a court hearing, and no outcome is reported.
Source: Ars Technica