OREXIGEN REPORTS RESULTS FROM STUDY OF OBESITY DRUG

Orexigen Therapeutics announced that Excalia, a combination of two centrally acting medications intended to provide and sustain clinically important weight loss, demonstrated significant weight loss in a six-month, double-blind, Phase IIa clinical study. The magnitude of weight reduction exceeded that seen with placebo. The findings showed that patients completing the blinded 24-week phase lost on average 9.2 percent of their weight from baseline using Excalia compared with an average of 0.4 percent weight loss from baseline for patients using placebo. The study results further demonstrate that weight loss continued through an additional 24-week open-label period, with Excalia patients achieving an average weight loss of 12 percent from baseline by 48 weeks.

Excalia is a proprietary combination of bupropion, a dopamine and norepinephrine reuptake inhibitor, plus zonisamide, an approved anticonvulsant medication. The company's preclinical research suggests that combining these two central nervous system drugs acts on a complex of neurons in the hypothalamus, the area of the brain contributing to the regulation of appetite, energy output and maintaining body weight. The compound was tested in a double-blind, placebo-controlled, randomized, proof-of-concept Phase II clinical study of 127 non-smokers with body mass indices (BMI's) between 30 and 40.

On categorical measures of response nearly three quarters (73 percent) of those who completed the study demonstrated a 5 percent weight loss, and half demonstrated a 10 percent weight loss at 24 weeks. After 24 weeks patients were re-randomized for the extension phase of the study. Those staying on their same dose of active therapy lost, on average, an additional 3 percent from the start of the study. Approximately one-third of subjects discontinued early due to an adverse event consistent with the existing package insert for zonisamide. In light of this rate, the company has implemented a strategy that it believes will result in improved tolerability in current and forthcoming trials for Excalia.