Is Ipsapirone an Effective Antidepressant?

If serotonin 1A (5-HT-1A) receptors mediate the antidepressant effects of SSRIs, then theoretically direct 5-HT-1A agonists should be effective antidepressants. This large, multicenter, randomized study compared the 5-HT-1A agonist ipsapirone (5 mg, 7.5 mg, or 10 mg three times daily) with placebo in 373 patients who met criteria for DSM-III-R major depression.

After eight weeks, only patients who received the intermediate dose of ipsapirone (7.5 mg) had a statistically significant reduction in Ham-D Rating Scale scores when compared with placebo recipients. However, the magnitude of this difference was only 2.5 points. Patients who received the intermediate dose also had significantly improved clinical global improvement and Montgomery and …