TAVNEOS Withdrawal Proposal Signals Data Integrity Reckoning

ChemoCentryx Inc., a wholly owned subsidiary of Amgen, Inc., now faces a formal proposal from CDER to withdraw market approval for TAVNEOS (avacopan), exposing a data integrity failure that QA directors and regulatory affairs teams across the industry cannot afford to treat as an isolated incident. The agency's finding that unblinded study personnel manipulated pivotal clinical trial results, and that the original unsupportive analysis was never disclosed to FDA, represents one of the most consequential enforcement actions in recent post-approval history under 21 CFR Part 211 and sponsor obligations governing clinical data submissions.

TAVNEOS received FDA approval on October 7, 2021, for use alongside glucocorticoids and other standard-of-care medications in adults with severe active ANCA-associated vasculitis, covering granulomatosis with polyangiitis and microscopic polyangiitis. CDER states that new information, which only became available more than three years after approval, revealed that the pivotal study's results were manipulated to show efficacy where the original analysis did not support that conclusion. The agency has concluded it can no longer confirm there has ever been a valid demonstration of effectiveness for the approved indication. A notice of opportunity for a hearing (NOOH) has been issued to ChemoCentryx.

Compounding the efficacy concerns, CDER has identified a serious and evolving hepatic safety signal. A March 31, 2026, drug safety communication documented cases of drug-induced liver injury (DILI) associated with TAVNEOS, including cases involving vanishing bile duct syndrome (VBDS), characterized by progressive destruction and disappearance of bile ducts. While hepatotoxicity was identified as a serious adverse reaction in premarket trials and reflected in labeling, VBDS and DILI cases with fatal outcomes represent new post-market safety concerns that were not captured in the original benefit-risk framework.

TAVNEOS will remain commercially available until ChemoCentryx voluntarily withdraws the product or the FDA Commissioner mandates removal. If the applicant requests a hearing, the Commissioner will determine whether to convene a public hearing before issuing a final withdrawal decision. In the interim, CDER recommends that healthcare professionals engage patients in individualized benefit-risk discussions regarding continued TAVNEOS use. For plant heads and QA leads, the case underscores the systemic risk of inadequate clinical data governance, the non-negotiable obligation to disclose all analyses to the agency, and the operational readiness required to respond when post-approval safety signals escalate beyond labeled warnings.