Substance P receptor antagonists: a new antidepressive and anxiolytic mechanism?

Preclinical investigations suggest that the neuropeptide substance P might be involved in the etiopathology of pain, depression, and anxiety. In a rec ent study, the substance P receptor antagonist MK-869 showed antidepressant and anxiolytic activity in depressed outpatients which was comparable to a standard SSRI. The MK-869 was well tolerated. Although these findings are promising, further studies are necessary to prove the hypothesis that subst ance P receptor antagonists represent a new class of antidepressants or anx iolytics. Respective studies are currently underway.