Plasma concentration and efficacy of tolvaptan in cirrhotic patients with refractory ascites

Abstract To investigate the relationship between the exposure and efficacy of tolvaptan, we measured pharmacokinetics of total drug at 7 days after repeated doses of 3.75 mg/day tolvaptan in 16 patients with hepatic edema. Nine patients (56.3%) were responders, which were defined as those with body weight reduction of >1.5 kg/week. Serum albumin levels were significantly lower in responders than in non-responders ( P  = 0.031). However, the pharmacokinetics varied greatly among individuals and was not relevant to the clinical response.