SB-649915

SB-649915 is a novel s-HTIA/B autoreceptor antagonist and serotonin reuptake inhibitor. SB-649915 (0.1–1.0 mg/kg, i.p.) significantly reduced ultrasonic vocalization in male rat pups separated from their mothers (ED50 of 0.17 mg/kg). In the marmoset human threat test SB-649915 (3.0 and 10 mg/kg, s.c.) significantly reduced the number of postures with no effect on locomotion. In the rat high light social interaction (SI), SB-649915 (1.0–7.5 mg/kg, t.i.d.) and paroxetine (3.0 mg/kg, once daily) were orally administered for 4, 7, and 21 days. SB-649915 is acutely anxiolytic and reduces the latency to onset of anxiolytic behavior compared with paroxetine in the SI model.