Zafgen Inc reported positive data on its obesity drug, which has been marred by two patient deaths, and said the data could help convince the U.S. Food and Drug Administration to allow it to restart trials on the drug. The company’s shares more than doubled on Wednesday on hopes that Zafgen could be allowed to develop its lead experimental drug, beloranib, which has been on clinical hold since December. Zafgen has said beloranib is the first treatment to show significant reduction in both body weight and hyperphagia-related behavior in patients with Prader-Willi syndrome (PWS), the most common genetic cause of life-threatening obesity.