n. an atypical antipsychotic agent of the benzisoxazole class that is active at a range of receptors. Its efficacy is thought to result particularly from its dopamine D2 and serotonin 5-HT2 receptor antagonism. Its wide-ranging receptor activity is thought to confer antipsychotic activity with fewer extrapyramidal symptoms and with a somewhat more favorable metabolic profile than is seen with other atypical antipsychotics. U.S. trade name: Fanapt.