The study has included patients with acute symptoms of schizophrenia who were treated either with Fiapta (iloperidone), a novel atypical antipsychotic agent or placebo. Patients were also studied for a genetic variation in the CNTF gene. About 75% of the population carries two intact copies of the CNTF protein while 25% carry one or two truncated copies of the protein.
In the patient population carrying both intact copies of CNTF (representing 75% of the population), Fiapta treatment was significantly better than placebo in symptom improvement. In patients carrying at least one truncated copy of the CNTF protein, placebo and Fiapta treated patients had a significant improvement from baseline indicating an enhanced placebo response among this group of patients.