A new study done by Columbia University of long-acting injectable antipsychotics for people with schizophrenia found that the newer, second-generation, medication paliperidone palmitate (Brand name Invega Sustenna by Janssen Pharmaceuticals) was no more effective than the older, less expensive haloperidol decanoate. This was so, even though the doses of the older medication given in the study were considerably lower than standard doses of the past. This study shows that the older medication is a cost-effective option for people who have had a history of medication non-adherence

Scott Stroup, MD, MPH, and colleagues affiliated with the National Institute of Mental Health-supported Schizophrenia Trials Network compared the two medications in 311 patients diagnosed with schizophrenia or schizoaffective disorder. “The two drugs were very similar to each other, and both were better than expected at preventing relapse,” said Dr. Stroup, a professor of psychiatry at Columbia University and the New York State Psychiatric Institute.

Treatment adherence is a challenge for many patients with schizophrenia, especially with oral medications that must be taken daily. Many experts believe that the use of long-acting injectable antipsychotics to improve adherence is underused.

“The use of long-acting injectable medications is an important strategy that may lead to fewer relapses and better outcomes,” said Dr. Stroup. “We should think of using long-acting injectables when there is a risk of relapse due to medication non-adherence. But it’s not necessary to start with an expensive, new long-acting medication.”

“This study,” he said, “also demonstrates the importance of independently funded research to provide unbiased comparisons of new and established medications.  Comparative effectiveness research studies such as this one help determine the appropriate role for new treatments.”

Though few study participants in either group stopped treatment because of side effects, the drugs tended to have different side effects. Patients who were assigned the newer antipsychotic reported more weight gain, while those assigned the older antipsychotic had more neurologic side effects, particularly restlessness. All patients, therefore, should be carefully monitored throughout treatment, said Dr. Stroup.

Research Paper Details and Link: “Effectiveness of Paliperidone Palmitate vs. Haloperidol Decanoate for Maintenance Treatment of Schizophrenia:  A Randomized Clinical Trial.”