RESEARCH WEEKLY: Promising New Medications for Schizophrenia
Drug development for treating schizophrenia is entering a promising new era. This week’s research blog is about some of these new developments written by Michael B. Knable, DO, psychiatrist and Treatment Advocacy Center Board President.
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The newest medication to reach the market for the treatment of schizophrenia is lumateperone1 (also known as Caplyta and produced by Intra-Cellular Therapies). Lumateperone was approved by the FDA in December 2019. Several different doses of lumateperone have been studied and it appears that an intermediate dose (42 mg) is most effective in reducing positive symptoms during an acute exacerbation of schizophrenia. There did not appear to be a significant effect of this medication on negative symptoms. Although studies that lead to FDA approval are usually short (4-6 weeks), and the true risk for side effects is often not known until patients have taken new medications for longer periods of time, it is encouraging that lumateperone did not appear to effect body weight, lipids, blood sugar, prolactin or to produce involuntary movements. Like most atypical antipsychotics, lumateperone blocks dopamine D2 receptors and serotonin 2A receptors. The manufacturer claims that lumateperone is novel because it also interacts with dopamine D1 receptors, glutamate and serotonin re-uptake. However, it is not possible to know how lumateperone compares to existing atypical antipsychotics since no direct studies of this question have been published. As of this writing, it appears that the monthly cost for lumateperone is approximately $1,300. Some Medicaid insurers may reimburse for this cost after prior authorization, but it is not yet clear whether private insurance companies will cover the cost of this medication.
Drug development for schizophrenia may be entering an interesting new era because a number of drugs currently under study are not new variations of dopamine receptor blockers. Recently, an interesting study was published on a new compound produced by Sunovion Pharmaceuticals (SEP-363856)2. This compound is thought to interact with the trace amine associated receptor (TAAR-1) and the serotonin 1A receptor, but not with dopamine receptors. In the four-week study, there was a significant improvement in symptoms of psychosis, but no apparent differences from placebo on metabolic measures or involuntary movements. I am looking forward to further studies and information about this interesting compound.
The following table includes several other compounds that are currently being studied and which are not dopamine blocking drugs. The NCT number in the last column of the table refers to the registration of these trials on www.ClinicalTrials.gov. You can find more information about these studies on that site. Let’s hope that I will have good news to share about these studies in future updates.
