This is a randomized, double-blind, placebo-controlled, Phase 2 safety/efficacy study in which two dose levels of EVP-6124 will be evaluated. Eligible for enrollment will be patients who meet clinical criteria for schizophrenia and who are taking chronic atypical anti-psychotic medication at a stable dose. This study will therefore evaluate the effects of EVP-6124 when administered concomitantly with anti-psychotic medication.
Patients will be randomized to one of the following groups: 0.3 mg or 1.0 mg EVP-6124, or placebo. Seventy-five patients per group. Study drug will be supplied as capsules and will be orally administered once daily for a total of 84 days.