Partial dopamine agonists in the treatment of psychosis.

The discovery and characterization of dopamine in the mammalian brain earned Dr. Arvid Carlsson the Nobel Prize in 2000. Along with his many insights about dopamine pharmacology, came his proposal of the existence and critical role of dopamine autoreceptors in the overall regulation of dopamine-mediated neurotransmission. In this paper, the rationale, the putative mechanisms, and pertinent clinical data are reviewed to support the idea of the clinical relevance of dopamine agonists, especially partial agonists, in the treatment of psychosis. Evidence was gathered for the usefulness of this strategy in schizophrenia in early trials with apomorphine and N-propylnoraporphine (NPA). But clinical relevance was not a reality before the application of (-)-3PPP. These clinical results are presented. Moreover, now a partial dopamine agonist, aripiprazole, has been developed and will likely be marketed by BMS and Otsuka for the treatment of psychosis and will be the first drug in this class to be commercially available. Partial dopamine agonists represent the next new class of antipsychotic drugs, effective in treating schizophrenia.