(Adds details, shares)
Sept 7 (Reuters) - Alnylam Pharmaceuticals Inc said on Thursday it stopped giving doses of its experimental drug for a rare bleeding disorder to patients enrolled in its clinical studies after one patient died.
Shares of the U.S. drug developer fell 14 percent to $74.00 in premarket trading.
A patient suffering from hemophilia A enrolled in a mid-stage study of Alnylam's experimental treatment, fitusiran, died after developing a blood clot, the company said.
The study was testing fitusiran as a treatment for hemophilia A and hemophilia B patients.
Alnylam said it expects to resume dosing of the drug in its clinical studies as soon as possible and potentially by late 2017.
Hemophilia is an inherited bleeding disorder in which the blood does not clot properly, leading to spontaneous bleeding and bleeding following minor injuries or surgery.
About 20,000 Americans are estimated to suffer from hemophilia, according to the U.S. Centers for Disease Control and Prevention.
French drugmaker Sanofi in November agreed to co-develop and co-commercialize fitusiran with Alnylam in the United States, Canada and Western Europe. (Reporting by Tamara Mathias in Bengaluru; Editing by Sai Sachin Ravikumar)