Omeros suspends mid-stage trial of Huntington's drug, shares fall

(Reuters) - Omeros Corp said it suspended enrolment in a mid-stage study testing its experimental Huntington's drug as the company evaluates data from a concurrent trial in rats, sending its shares down 10 percent before the bell. A high dose of the drug, OMS824, in several rats demonstrated a much higher drug concentration in the blood, than has been measured in patients, the company said. The drug has been well tolerated in all human trials, Omeros said. "Based on currently available data, we do not believe that the observation in the rats is caused by OMS824," Chief Executive Gregory Demopulos said in a statement on Tuesday. The U.S. Food and Drug Administration has asked the company to further evaluate the data from the 13-week rat study before restarting the trial, Omeros said. The preclinical study was being conducted to allow longer duration human trials for the drug. The suspended mid-stage study was evaluating the drug in patients with Huntington's - an inherited disease that causes the progressive degeneration of certain brain cells - for four weeks. The Seattle-based company is also developing OMS824 for the treatment of schizophrenia. (Reporting by Natalie Grover in Bangalore; Editing by Sriraj Kalluvila)