A Comparison of Long-acting Injectable Medications for Schizophrenia

The purpose of this comparative effectiveness research study is to learn more about different medications called antipsychotics that are used to treat schizophrenia or schizoaffective disorder. Specifically, we are looking at long-acting medications that are given by injection every month, instead of being taken by mouth every day. In this multi-site study, we are comparing the risk and benefits of two FDA-approved long-acting injectable medications (paliperidone palmitate and haloperidol decanoate). Study participants with schizophrenia or schizoaffective disorder are expected to benefit from the improved medication schedule. This study aims to enroll 360 individuals with schizophrenia or schizoaffective disorder for whom treatment with a long-acting injectable antipsychotic medication is likely to be helpful. Study participants will be randomly assigned to treatment with either paliperidone palmitate and haloperidol decanoate for up to 24 months. Participants will have an equal chance of being assigned to each medication, however participants will not know which medication they are taking.