Mixed trial results for Sunovion's bipolar depression candidate

Sunovion Pharmaceuticals, a US subsidiary of Japan’s Sumitomo Dainippon Pharma (TYO: 4506), has released top-line results from study SEP380-201 that did not hit main goal, but are still seen to be encouraging.

The global, multicenter, randomized, double-blind, placebo-controlled clinical trial was designed to evaluate the efficacy, safety, and tolerability of treatment with SEP4199, an investigational oral medicine for the treatment of major depressive episodes associated with bipolar I disorder (bipolar I depression). SEP-4199 is a non-racemic ratio of amisulpride enantiomers with increased potency for serotonin 5-HT7 receptors relative to dopamine D2 receptors.

According to the top-line results for the primary endpoint, which included data from Europe and the USA, patients with bipolar I depression, SEP-4199 showed numerical improvement in the Montgomery Åsberg Depression Rating Scale (MADRS) total score compared to placebo after six weeks of treatment (200mg: -19.5 versus -16.2, 400mg: -19.3 vs -16.2 respectively, both dose groups vs placebo, p=0.054; 200 mg group effect size (ES) = -0.31 and 400mg group ES = -0.29).