[An antipsychotic without dopamine receptor blockade?] / Een antipsychoticum zonder dopamine­receptorblokkade?

BACKGROUND: Current antipsychotic treatment is suboptimal. There is an urgent need for new antipsychotics with new mechanisms of action. SEP-363856 is a trace amine-associated receptor 1 (TAAR1) agonist and a serotonin 5-HT1a agonist with potential antipsychotic properties. AIM: To describe the rationale for the development of SEP-363856, the pharmacology of TAAR1/5-HT1a agonists, and the clinical efficacy of SEP-363856. METHOD: A narrative review of the literature using PubMed, Embase and PsychINFO. RESULTS: Six publications were identified, one of which was a phase 2 clinical trial with SEP-363856. This phase 2 study shows that SEP-363856 is an effective and well-tolerated antipsychotic; positive, but also negative symptoms decreased; motor side effects (akathisia) and prolactin increase did not occur, while metabolic side effects hardly occurred. Reported side-effects were somnolence and nausea. The antipsychotic activity of SEP-363856 appears to be (pre)clinical not based on D2 antagonism, but on TAAR1 and 5-HT1a agonism. CONCLUSION: TAAR1 and 5-HT1a agonists such as SEP-363856 may be a treatment option for psychosis. Hopefully they can be further developed into an antipsychotic with a favorable effectiveness and tolerability profile.