Cognitive impairment is a cause of significant disability in patients with schizophrenia. To date, no drug has been approved for this indication by the U.S. Food and Drug Administration. This article presents findings suggesting that a medication targeting the alpha-7 nicotinic acetylcholine receptor (α7 nAChR) might meet this need. This single-center, randomized, parallel-group, double-blind,placebo-controlled study examined 21 medically stable patients with schizophrenia or schizoaffective disorder treated with second generation antipsychotics. Patients were treated with a daily dose of either 0.3 mg (n=8) or 1.0 mg (n=9) of EVP-6124, an α7 nAChR partial agonist, or placebo (n=4). Treatment continued for 21 days while patients continued their usual antipsychotic medication: aripiprazole (10-30 mg/day), olanzapine (10-20 mg/day), paliperidone (3-12 mg/day), or risperidone (2-16 mg/day). Cognitive test performance, eventrelated electroencephalographic (EEG) potentials, clinical symptoms, laboratory values, and clinical side effects were measured. EVP-6124 was well tolerated and showed positive, and in some cases, dose-dependent effects on several EEG responses, especially the Mismatch Negativity and P300 potentials. Positive effects were also found in performance on cognitive tests that measured non-verbal learning, memory, and executive function. This study is an example of the type of early proof of concept trial that is done to enable drug developers to evaluate whether to continue research on an agent. Based on the promising findings in this study, larger phase II studies were initiated to further test the pro-cognitive effects of EVP-6124 in patients with chronic schizophrenia.
Clinical trials registration: Safety, Tolerability, and Pharmacokinetic Study of EVP-6124 in Patients with Schizophrenia, NCT01556763 http://clinicaltrials.gov/ct2/show/NCT01556763?term=NCT01556763&rank=1.