The FDA’s actions involving ChemoCentryx’s avacopan (Tavneos) came under renewed focus after an investigation prompted steps toward withdrawal from the U.S. market. The allegation centered on new information that emerged after approval, including claims that unblinded study personnel manipulated pivotal results and that the original analysis was not disclosed to the FDA. Tavneos has previously been approved in the U.S. and Europe, and Amgen acquired ChemoCentryx after the pivotal trial in 330 patients. European regulators initiated investigations around data integrity, while the FDA’s CDER moved toward withdrawal over the inability to conclude effectiveness for approved use. For biopharma stakeholders, the case is a high-impact reminder that data integrity findings can overturn clinical conclusions even after an approval—directly affecting patient access and downstream commercial strategy.