The U.S. Food and Drug Administration flags serious and fatal liver injury, including vanishing bile duct syndrome, linked to Tavneos (avacopan) in postmarketing data.
Written By: Vikas Londhe,
Chief Editor and Patient Safety Expert
The U.S. Food and Drug Administration has issued a safety communication warning of serious liver injury, including fatal outcomes, in patients treated with Tavneos (avacopan) for severe active anti-neutrophil cytoplasmic autoantibody (ANCA) associated vasculitis.
The alert follows a review of postmarketing data that identified cases of drug-induced liver injury (DILI), some progressing to vanishing bile duct syndrome (VBDS), a rare but severe condition marked by progressive loss of bile ducts and impaired bile flow. These complications represent emerging safety concerns beyond the known hepatotoxicity described in the drug’s labeling.
Tavneos, approved in October 2021, is used alongside glucocorticoids and other standard therapies to treat adults with severe active anti-neutrophil cytoplasmic autoantibody (ANCA)-associated vasculitis, a rare autoimmune condition affecting small- to medium-sized blood vessels.
Postmarketing Findings Signal Elevated Risk
The FDA identified 76 cases of DILI with a reasonable causal association to avacopan use. Among these, 74 were serious, including 54 hospitalizations and 8 deaths. Most cases showed a cholestatic or mixed liver injury pattern, often with marked elevations in alkaline phosphatase and bilirubin. The median time to onset was 46 days after treatment initiation.
Notably, 7 cases involved biopsy-confirmed VBDS, all requiring hospitalization, with 3 resulting in death.
Monitoring and Management Recommendations
The FDA advises healthcare professionals to closely monitor liver function in patients receiving Tavneos. Recommended testing includes liver panels every two weeks during the first month, followed by monthly assessments for the next five months, and thereafter as clinically indicated.
Treatment should be discontinued promptly in patients showing clinically significant abnormalities, specifically when alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels exceed three times the upper limit of normal (ULN), or when alkaline phosphatase (ALP) rises above two times the ULN.
Discontinuation is also advised in patients presenting with symptoms of cholestasis, such as jaundice or pruritus. If liver test abnormalities or symptoms do not improve, referral to a hepatologist for further evaluation is recommended.
Patient Safety Advisory
Patients are urged to seek immediate medical attention if they experience symptoms suggestive of liver injury, including fatigue, nausea, vomiting, itching, yellowing of the skin or eyes, dark urine, or abdominal pain. Decisions regarding continuation or switching therapy should be made in consultation with healthcare providers.
The FDA continues to monitor reports of liver injury associated with avacopan and will provide updates as new data emerge. The agency also encourages reporting of adverse events through its MedWatch program to support ongoing pharmacovigilance efforts.
Reference
FDA Identifies Cases of Serious Liver Injury in Patients Taking Tavneos (avacopan) for Severe Active Anti-neutrophil Cytoplasmic Autoantibody (ANCA)-associated Vasculitis, 31 March 2026, https://www.fda.gov/media/191708/download?attachment
About the Writer
Vikas Londhe is the Chief Editor and a subject matter expert in patient safety and drug safety. He has a deep understanding of pharmacology, medication-related risks, patient and drug-related errors, and global drug regulatory frameworks. Through his work, he focuses on translating complex medical and regulatory information into clear, evidence-based insights that support safer medication use and informed healthcare decisions.
