NEJM Retracts Pivotal Trial Behind Amgen's Tavneos Amid Escalating FDA and EMA Regulatory Stand-Off
On June 29, 2026, The New England Journal of Medicine (NEJM) retracted the pivotal 2021 study supporting the approval of Amgen's rare disease drug Tavneos (avacopan). The retraction follows an ongoing Food and Drug Administration (FDA) investigation which concluded that primary endpoint assessments for nine patients were readjudicated after database lock and trial unblinding—conduct that was not disclosed in the published paper.
This development severely complicates Amgen’s efforts to defend the drug, which it acquired in its $3.7 billion buyout of ChemoCentryx. The FDA requested the voluntary withdrawal of Tavneos in January 2026 and formally proposed to rescind its approval in April 2026, citing "manipulated" trial data. Rather than withdrawing the drug, Amgen requested a formal hearing and commissioned the Duke Clinical Research Institute (DCRI) to conduct an independent, fully blinded re-adjudication of the ADVOCATE trial results. Amgen is scheduled to submit these results to the FDA by July 29, 2026.
Meanwhile, the European Medicines Agency's (EMA) Committee for Medicinal Products for Human Use (CHMP) recently reversed its marketing recommendation for Tavneos1, and the drug is facing intense safety scrutiny over dozens of cases of drug-induced liver injury, including eight patient deaths in the US and 20 in Japan.
"Monday, the New England Journal of Medicine said it’s retracting the phase 3 study results on Tavneos first published in 2021.2 An investigation by the FDA has concluded that 'the primary end-point assessments in nine patients were readjudicated after database lock and trial unblinding,' according to the retraction notice."
"In February 2026, Amgen proactively initiated an independent, fully blinded re-adjudication of the primary endpoint results from the ADVOCATE study conducted by the Duke Clinical Research Institute... Those results will be shared with the FDA as part of our hearing submission due by July 29 and submitted for publication."
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An instance of Identical clinical trial packages no longer secure synchronized transatlantic drug approvals. — This finding highlights the escalating regulatory split where European regulators move toward revocation due to study execution flaws while the US process remains ongoing. ↩︎
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An instance of Data integrity failures trigger a global regulatory crackdown on clinical trial validity. — An investigation showing compromised trial data led a leading journal to retract a pivotal clinical study, disrupting a multi-billion-dollar therapeutic approval. ↩︎