The FDA moved to withdraw Amgen’s Tavneos (avacopan) after alleging that information used to support approval included untrue statements of material fact and that trial results were manipulated. The action adds to mounting scrutiny on the underlying evidence package that supported the 2022 buyout of Chemocentryx for $3.7 billion. Separately, the reporting describes the FDA’s concern that the developer concealed analysis and altered data, escalating the agency’s attempt to remove the therapy from the market. Amgen has disputed the decision, refusing to voluntarily withdraw and maintaining the product is safe. For sponsors and CROs, the case raises the operational risk around data handling, analysis transparency, and documentation practices across pivotal programs.