SAN DIEGO (AP) — Orexigen Therapeutics Inc. said Wednesday its potential obesity treatment Empatic met key goals in a midstage study and the company plans to move the drug candidate into late-stage development. Orexigen said it plans to meet with the Food and Drug Administration to discuss plans for a Phase III clinical trial. The drug is a combination of the antidepressant Wellbutrin and the seizure medication zonisamide. The study involved 729 people either taking Empatic or placebo. The company said 60.4 percent of patients given Empatic lost more than 5 percent of their body weight in the 24-week study, compared with 14.7 percent of patients taking placebo. Orexigen also has another obesity drug Contrave in late-stage development and plans to seek FDA approval in 2010. Contrave combines bupropion, a drug used to treat depression and smoking habits, with naltrexone, which is to used to fight alcoholism and opiate addiction. Orexigen could face competition as two other California-based companies, Arena Pharmaceuticals Inc. and Vivus Inc., seek to bring their own late-stage obesity drugs to market. Shares of Orexigen rose as much as 8.4 percent in premarket trading on Wednesday. Its shares recently changed hands at $9.93, up 10 cents. Meanwhile, shares of Arena gained 8 cents, or less than 1 percent, to $4.56, while Vivus advanced 87 cents, or 8.5 percent, to $11.07.