The Pharmacokinetics and Pharmacodynamics of Tolvaptan in Patients with Liver Cirrhosis with Insufficient Response to Conventional Diuretics: a Multicentre, Double-blind, Parallel-group, Phase III Study

OBJECTIVES: This study investigated the pharmacokinetic and pharmacodynamic profile of tolvaptan, and verified its efficacy and safety in patients with liver cirrhosis-associated ascites, with insufficient response to conventional diuretic treatment. METHODS: This multicentre, double-blind, parallel-group study allocated patients with cirrhosis to receive either 3.75 or 7.5 mg/day tolvaptan orally, once daily, for 7 days. Pharmacokinetic, pharmacodynamic and efficacy variables were measured. RESULTS: Tolvaptan was shown to have high plasma concentrations, and prolonged duration of maximum concentration and half life, in these patients with impaired hepatic function. Tolvaptan resulted in dose-dependent decreases in body weight and ascites volume, and increases in urine output. There were no effects on urinary or serum electrolytes. Tolvaptan was well tolerated, with a good safety profile. CONCLUSIONS: Tolvaptan at 3.75 mg/day exerts some effects due to the pharmacokinetic profile in patients with liver cirrhosis. Tolvaptan at 7.5 mg/day is a clinically useful option for treating patients who do not respond well to conventional diuretics.