Invega was more effective than placebo and as effective as olanzapine in reducing the symptoms of schizophrenia. In the first short-term study, patients taking placebo had an average fall in their symptom score of 4.1 points, compared with an average fall of between 17.9 and 23.3 points in those taking Invega and of 19.9 in those taking olanzapine. Similar results were seen in the other two short-term studies. Across all three studies, higher doses of Invega were more effective than lower doses in reducing symptoms.
Invega was also more effective than placebo in preventing the occurrence of new symptoms of schizophrenia in the long-term study.
In the studies in patients with schizoaffective disorder, Invega was more effective than placebo. In the first study, patients who were given Invega had a fall in their symptom score of between 27.4 and 30.6 compared with 21.7 in patients who were given placebo. In the second study, the fall in symptom score was 20.0 in the Invega group and 10.8 in the placebo group.