FDA wants Tavneos off the market. Amgen won’t budge.\n\nThe agency proposed withdrawing approval of the rare-disease drug in April, after finding that unblinded study personnel manipulated results from the pivotal ADVOCATE trial. The New England Journal of Medicine later retracted the paper that supported Tavneos’s 2021 approval. The European Medicines Agency has recommended revoking authorization too.\n\nAmgen isn’t backing down. It refused the FDA’s January request to voluntarily pull the drug, and it’s now demanding a hearing on the withdrawal, with additional materials due July 29. Its defense: endpoint assessments for nine patients were reassessed after database lock, but the company says the underlying evidence still shows Tavneos works.\n\nThe stakes reach past one niche vasculitis drug. Amgen bought ChemoCentryx for $3.7 billion in 2022, and $2.4 billion of intangible assets on its books are still tied to that deal. Tavneos is just 1% of Amgen’s revenue, but sales jumped 62% last year to $459 million, and analysts had it pegged to backstop the rare-disease franchise once gout drug Krystexxa loses patent protection. Losing the hearing would force a writedown on that $2.4 billion bet, on top of killing the product line.\n\nTwo patient groups have urged the FDA to keep Tavneos on shelves, warning that the alternatives carry serious risks of their own. The FDA closed its public comment docket on June 29. Amgen’s deadline to file its rebuttal: July 29.\n\nSarah Chen