Zafgen Inc. said its trial of an experimental drug to fight obesity was placed on hold by U.S. regulators after a second patient died.
The trial, in patients with a rare genetic disease called Prader-Willi syndrome that causes overeating, was the last study Zafgen needed to complete before the U.S. Food and Drug Administration would decide whether to approve the drug for those patients.
While Zafgen had finished the part of the trial that compared effects of the drug to a placebo, it continued with an extension phase in which all the patients took the drug. The FDA ordered a complete clinical hold, meaning Zafgen must stop this extension phase and all other clinical work on the drug, the drugmaker said Wednesday in a statement.