Safety and Cognitive Function Study of EVP-6124 in Patients With Schizophrenia

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.

Inclusion Criteria:

- Subjects who meet clinical criteria for schizophrenia or schizo-affective disorder
utilizing the structured clinical interview (SCI)

- Must be treated with a second generation anti-psychotic drug other than clozapine at a
stable dose for at least 4 weeks and must have been on that drug and clinically stable
for at least 8 weeks

- Must have no more than "moderate" severity rating for negative symptoms: BPRS item ≤4

- A minimal level of extrapyramidal symptoms (EPS); Simpson-Angus Scale total score ≤6

- A minimal level of depression; Calgary Depression Scale total score ≤10

- Must have a general health status acceptable for participation in a 12-week clinical
trial

- Fluency (oral and written) in the language in which the standardized tests will be
administered

- If a smoker, the ability to refrain from smoking for at least 30 minutes prior to any
cognitive testing

Exclusion Criteria:

General

- Insufficiently controlled diabetes mellitus in the judgment of the investigator

- Malignant tumor within the last 5 years with the exception of squamous and basal cell
carcinoma or cervical carcinoma it situ

- Pregnancy, nursing, (or if fertile female) not willing to utilize birth control
measures during study

- Unstable medical condition that is clinically significant in the judgment of the
investigator: major organ system dysfunction