Ursodeoxycholic Acid as Treatment for Polycystic Liver Disease

Rationale: Polycystic liver disease (PLD) is a rare disorder characterized by \>20 fluid-filled hepatic cysts. Polycystic livers are present in the combination with renal cysts as a manifestation of autosomal dominant polycystic kidney disease (ADPKD), or isolated in the absence of renal cysts as autosomal dominant polycystic liver disease (ADPLD or PCLD). PLD patients are confronted with symptoms caused by the mass effect of their polycystic liver every day for the rest of their life. There is no standard therapeutic option for symptomatic PLD patients. Current options are fairly invasive or their efficacy is only moderate. Preliminary data in our research lab have shown that ursodeoxycholic acid (UDCA) inhibited the proliferation of polycystic human cholangiocytes in vitro through the normalization of the intracellular calcium levels in cystic cholangiocytes. The investigators also found that daily oral administration of UDCA for 5 months to polycystic kidney disease (PCK) rats, an animal model of ARPKD that spontaneously develops hepato-renal cystogenesis, resulted in inhibition of hepatic cystogenesis. The investigators hypothesize that UDCA is an effective therapeutic tool in reducing liver volume in PLD. Objective: First, to demonstrate whether UDCA-therapy is effective in reducing total liver volume in PLD patients. Second, the investigators want to assess if UDCA modifies quality of life. Finally, the investigators want to assess safety and tolerability. Study design: International, multicenter, randomized, controlled trial Study population: 34 subjects (18 ≤age ≤ 80 years) suffering from symptomatic polycystic liver disease with underlying diagnosis of (PCLD or ADPKD), defined as ≥ 20 liver cysts on CT-scan and liver volume of ≥ 2500. Symptomatic is defined as Eastern Cooperative Oncology Group- Performance Score (ECOG-PS) ≥ 1 and having at least three out of ten PLD symptoms. Intervention: The patients will be randomized (1:1) into two groups. One gro