Results of phase 3 of the CATIE schizophrenia trial

The Clinical Antipsychotic Trials of Intervention Effectiveness (CATIE) study examined the comparative effectiveness of antipsychotic treatments for individuals with chronic schizophrenia. Patients who had discontinued antipsychotic treatment in phases 1 and 2 were eligible for phase 3, in which they selected one of nine antipsychotic regimens with the help of their study doctor. We describe the characteristics of the patients who selected each treatment option and their outcomes.

Two hundred and seventy patients entered phase 3. The open-label treatment options were monotherapy with oral aripiprazole, clozapine, olanzapine, perphenazine, quetiapine, risperidone, ziprasidone, long-acting injectable fluphenazine decanoate, or a combination of any two of these treatments.

Few patients selected fluphenazine decanoate (n=9) or perphenazine (n=4). Similar numbers selected each of the other options (range 33-41). Of the seven common choices, those who selected clozapine and combination antipsychotic treatment were the most symptomatic, and those who selected aripiprazole and ziprasidone had the highest body mass index. Symptoms improved for all groups, although the improvements were modest for the groups starting with relatively mild levels of symptoms. Side effect profiles of the medications varied considerably but medication discontinuations due to intolerability were rare (7% overall).

Patients and their doctors made treatment selections based on clinical factors, including severity of symptoms, response to prior treatments, and physical health status. Fluphenazine decanoate was rarely used among those with evidence of treatment non-adherence and clozapine was underutilized for those with poor previous response. Combination antipsychotic treatment warrants further study.