It reduces the expression of class 1 HLA on Original studies from France showed that administration of URSO improved liver function and slowed the progression of disease, thus reducing probability of death or the need for transplantation. Results were less satisfactory if, on entry to the trial, the patient had a high serum bilirubin level and cirrhosis was present. Symptoms such as pruritus and fatigue are unaffected. A multinational controlled trial confirmed that URSO reduces the time to death or transplantation. It does not cure the disease.
Results are better if referral is early.