European regulators moved to revoke Amgen and Vifor’s complement inhibitor Tavneos (avacopan) after a review concluded the original marketing authorization evidence could no longer be relied upon. The EMA’s committee, as reflected in CHMP recommendations, cited that the data underpinning the approval were “incorrect and misleading.” The CHMP’s stance aligns with an FDA withdrawal proposal, setting up additional scrutiny on the integrity of the Advocate trial dataset used for the European submission. Together, the twin agency actions increase the risk of market pullbacks and reimbursement disruption across multiple geographies. For biotech operators with rare-disease and immunology assets, the Tavneos case underscores how post-approval oversight can rapidly alter commercialization trajectories when appraisal reviews find data issues rather than pure efficacy disagreements.