Overview
- On Thursday, May 21, 2026, the Ministry of Health instructed Kissei Pharmaceutical to add a new "warning" section to Tabneos’s package insert and the company issued a safety bulletin to clinicians.
- Authorities say 20 patients who took Tabneos have died and that 13 of those cases showed vanishing bile duct syndrome, with about 210 suspected liver-related reports identified since the drug’s 2022 approval.
- An estimated 12,000–13,000 patients have used Tabneos in Japan since June 2022, which regulators cited when urging clinicians to refrain from starting new patients on the drug.
- New guidance notes liver dysfunction often appears within three months of starting treatment, advises regular liver testing during therapy, and calls for immediate treatment stop if abnormalities or symptoms such as jaundice or abdominal pain appear.
- Regulators and Kissei say the causal link is still under investigation because vasculitis itself can be severe, and the probe could lead to further label changes or tighter clinical controls depending on findings.