Brexpiprazole: a new leaf on the partial dopamine agonist branch

Area of Science:

• Pharmacology
• Neuroscience
• Psychiatry

Background:

• Brexpiprazole is a novel dopamine D2 partial agonist antipsychotic.
• It shares similarities with aripiprazole but has distinct receptor binding profiles.

Purpose of the Study:

• To review brexpiprazole and compare its efficacy and side effect profile with aripiprazole.
• To evaluate brexpiprazole's potential as a 'metabolically-friendly' antipsychotic option.

Main Methods:

• Review of brexpiprazole's pharmacological properties.
• Comparison of neurochemical profiles and receptor potencies between brexpiprazole and aripiprazole.
• Analysis of pivotal trial data for efficacy and safety.

Main Results:

• Brexpiprazole and aripiprazole are partial agonists at dopamine D2 and serotonin 5-HT1A receptors, and antagonists at serotonin 5-HT2A and noradrenergic α1B receptors.
• Neurochemical profiles suggest comparable antipsychotic efficacy but potentially less akathisia, extrapyramidal side effects (EPS), and activation with brexpiprazole.
• Pivotal trials confirmed brexpiprazole's efficacy in schizophrenia and treatment-resistant depression, with potential for minor weight gain and prolactin elevation.

Conclusions:

• Brexpiprazole demonstrates antipsychotic efficacy and is approved for schizophrenia and antidepressant-resistant depression.
• While efficacy appears comparable to aripiprazole, brexpiprazole may offer a better side effect profile, particularly regarding akathisia.
• Further clinical experience is needed, but brexpiprazole represents a promising new option for psychoses and mood disorders.