Maintenance of long-term efficacy and safety of quetiapine in the open-label treatment of schizophrenia

As schizophrenia is a chronic disorder, it is important that treatment be given over a long period of time to avoid relapse. Quetiapine, an atypical antipsychotic, has established efficacy and good tolerability in the short-term treatment of schizophrenia. This study investigated the long-term efficacy and safety of quetiapine in 674 patients with schizophrenia using combined data from the open-label extension phase of four Phase IIIa trials. The results showed that quetiapine, at a mean daily dose of 472.4 mg, provided progressive improvement and maintenance in the Brief Psychiatric Rating Scale total, positive- and negative-symptoms cluster, Clinical Global Impression Severity of Illness, and Scale for the Assessment of Negative Symptoms total scores over 208 weeks and beyond. Furthermore, quetiapine was well tolerated throughout the study period, with a low incidence of extrapyramidal symptom-related adverse events. In conclusion, quetiapine may be a suitable therapy in the long-term treatment of schizophrenia. (C) 2004 Lippincott Williams Wilkins.