A Drug Interaction Study of Valproic Acid and Single-dose Paliperidone Extended-Release (ER) in Healthy Men

Inclusion Criteria:

• Signed informed consent obtained indicating an understanding of the purpose of and procedures required for the study and willingness to participate in the study
• Agree to use an adequate contraception method as deemed appropriate by the study physician (for example, vasectomy, double-barrier, partner using effective contraception) and to not donate sperm during the study and for 3 months after receiving the last dose of study drug
• Have a body mass index (BMI, weight [kg]/height2 [m]2) between 18 and 30 kg/m2 (inclusive) and body weight not less than 50 kg
• Have a systolic blood pressure between 90 and 140 mm Hg and a diastolic blood pressure between 50 and 90 mm Hg
• Habitually smokes no more than 10 cigarettes, or 2 cigars, or 2 pipes of tobacco per day for at least 6 months before first study drug administration

Exclusion Criteria:

• History of or current clinically significant medical illness including (but not limited to) drug or alcohol abuse within the past 5 years, cancer with exception of basal cell carcinoma, epilepsy, suspected urea cycle disorder, any severe pre-existing gastrointestinal narrowing or malabsorption problems, cardiac arrhythmias or other cardiac disease, hematologic disease, coagulation disorders (including any abnormal bleeding or blood dyscrasias), lipid abnormalities, significant pulmonary disease, including bronchospastic respiratory disease, diabetes mellitus, renal or hepatic insufficiency, thyroid disease, neurologic or psychiatric disease, infection, or any other illness that the study physician considers should exclude the healthy volunteer or that could interfere with the interpretation of the study results
• Known allergy or intolerance to study drugs including paliperidone, valproic acid (VPA), sodium valproate, or divalproex sodium or any of the excipients (inactive substances) of the drugs (such as lactose)
• Donated blood or blood products or had substantial loss of blood (more than 500 mL) within 3 months before the first administration of study drug or intention to donate blood or blood products during the study or within 1 month after the completion of the study
• Unable to swallow solid, oral dosage forms whole with the aid of water (participants may not chew, divide, dissolve, or crush the study drugs)
• Preplanned surgery or procedures that would interfere with the conduct of the study