Biotech firm Vanda Pharmaceuticals (VNDA -3.54%) announced in a press statement Thursday that a phase 2b/phase 3 clinical trial studying the efficacy and safety of the drug tasimelteon in treating major depressive disorder (MDD) failed to meet its primary endpoints. The company has thus ended its program of targeting tasimelteon as a treatment for MDD.

The trial showed the drug to be safe, but tasimelteon only performed about as well as a placebo in reducing MDD symptoms in patients. Each managed to post around a 40% reduction in symptoms from a baseline.

Vanda CEO and President Dr. Mihael H. Polymeropoulos was quoted in the press release as saying, "These results are disappointing, as there is still a significant unmet medical need for patients with Major Depression." However, he said Tasimelteon's application in the treatment of blind individuals with non-24-hour sleep-wake disorder, a chronic circadian rhythm sleep disorder, remains the company's "top priority" as it aims for a New Drug Application submission in the middle of this year.