A Study of the Pharmacokinetics of Paliperidone in Volunteers With Normal or Impaired Liver Function

This is a single-dose, parallel-group, open-label, single-center, Phase 1 study of immediate release (IR) paliperidone in patients having either normal or moderately-impaired hepatic function. The groups, which will consist of 10 patients each, will be demographically matched with respect to age, weight, sex, and ethnicity. The study will consist of a screening period of up to 3 weeks and an open-label, single-dose treatment period (Days 1 through 5). On Day 1, a single dose of 1 mg Intermediate Release (IR) paliperidone oral solution will be administered after a fast of at least 10 hours; patients will continue to fast for 4 hours following study drug administration. The 96-hour follow-up will consist of serial sample collections of blood and urine for pharmacokinetic analysis and safety and tolerability assessments. Patients will remain confined to the study site through the 72-hour pharmacokinetics sampling and will consume standard institutional meals while in the study site. Patients will be released after the 72-hour sampling, then will return to the study site on Day 5 before the 96-hour pharmacokinetics sampling; end-of-study procedures will be performed immediately thereafter. Currently, pharmacokinetic data are available after oral IR and Extended Release (ER) formulations of paliperidone were administered to healthy patients and to patients with schizophrenia who had normal hepatic function. No pharmacokinetic information on paliperidone in patients with hepatic impairment has been obtained. The target population for paliperidone comprises schizophrenic patients. Because some patients in the target population might be hepatically impaired, pharmacokinetic information in this population is helpful. This single-dose pharmacokinetic study will collect information in patients with normal hepatic function and in patients with moderate hepatic impairment to provide clinical dosing information/recommendations for patients with hepatic impairment. Safety and tolerability will be monitored. A single dose of 1 mg intermediate release (IR) paliperidone oral solution