A validation study of the Ursodeoxycholic Acid Response Score in Japanese patients with primary biliary cholangitis

Background/Purpose Although ursodeoxycholic acid (UDCA) is a first‐line treatment for primary biliary cholangitis (PBC), 20%‐30% of patients with PBC exhibit an incomplete response to UDCA. Recently, the UDCA Response Score was proposed for predicting response to UDCA using pretreatment parameters in patients with PBC. We aimed to validate the UDCA Response Score in Japanese patients with PBC. Methods Registry data of Japanese patients (n = 873) were collected. Patients with data on all clinical parameters required for calculating the UDCA Response Score were selected. The endpoint was UDCA response, defined as alkaline phosphatase