Brexpiprazole is best described as which of the following?

Brexpiprazole is best described as which of the following?

• A. Partial agonist for 5-HT1A, D2, D3; high affinity for D2 and D3
• B. Full antagonist at D2
• C. Partial agonist at 5-HT2A only
• D. No receptor activity

Answer: (A)

Brexpiprazole works by dialing down dopamine and tuning serotonin signaling rather than simply blocking receptors. It acts as a partial agonist at dopamine D2 receptors and at D3 receptors, and also as a partial agonist at serotonin 5-HT1A receptors, with particularly high affinity for D2 and D3. This means it can dampen excessive dopaminergic activity related to psychosis while preserving some dopaminergic tone to reduce movement-related side effects, and the 5-HT1A activity adds potential antidepressant/anxiolytic benefits. It also has 5-HT2A antagonism, which complements its antipsychotic effects, but the key descriptor is the partial agonism at D2, D3, and 5-HT1A with high D2/D3 affinity. The other options describe full antagonism, limited receptor activity, or no receptor activity, which don’t fit brexpiprazole’s pharmacology.

Brexpiprazole works by dialing down dopamine and tuning serotonin signaling rather than simply blocking receptors. It acts as a partial agonist at dopamine D2 receptors and at D3 receptors, and also as a partial agonist at serotonin 5-HT1A receptors, with particularly high affinity for D2 and D3. This means it can dampen excessive dopaminergic activity related to psychosis while preserving some dopaminergic tone to reduce movement-related side effects, and the 5-HT1A activity adds potential antidepressant/anxiolytic benefits. It also has 5-HT2A antagonism, which complements its antipsychotic effects, but the key descriptor is the partial agonism at D2, D3, and 5-HT1A with high D2/D3 affinity. The other options describe full antagonism, limited receptor activity, or no receptor activity, which don’t fit brexpiprazole’s pharmacology.