Ursodeoxycholic acid in primary biliary cirrhosis: no evidence for toxicity in the stages I to III.

In an open, exploratory study, the safety of ursodeoxycholic acid (UDCA) in the treatment of primary biliary cirrhosis (PBC) was investigated. Seven patients in stages I to III and two patients in stage IV were treated for 1 year with 1 g/day of UDCA. Clinical symptoms, and alkaline phosphatase, gamma-glutamyltransferase, alanine aminotransferase (GOT) and aspartate aminotransferase (GTP) levels improved significantly within three months and remained at the lower levels for the period of observation. Results of the galactose elimination capacity (4.7 +/- S.D. 1.4 mg/min per kg) and the aminopyrine breath test (0.60 +/- 0.33% dose/kg per mmol CO2) remained unchanged for 1 year. In all patients total serum bile acids increased and quantitatively UDCA became the most important bile acid. In patients in stages I to III this increase, however, was modest, whereas in patients in stage IV, total serum bile acids reached levels of 140 and 157 mumol/l and UDCA, levels of 90 and 103 mumol/l, respectively. It is concluded that UDCA appears to be safe only in stages I to III and that prognostic stratification based on bile acid levels or on the histological stage of the disease should be an important aspect of controlled clinical trials.