Eagle Pharmaceuticals' licensor granted U.S. patent for dantrolene Eagle Pharmaceuticals announced that the United States Patent and Trademark Office has granted Patent No. 8,685,460 for the treatment of heat stroke with Eagle’s dantrolene sodium for injectable suspension. This patent issued expires in 2023. Eagle’s dantrolene formulation for the treatment of Exertional Heat Stroke was granted Orphan Drug designation by the Food and Drug Administration on September 25, 2012. Eagle is currently developing dantrolene in this new EHS indication. The company filed an NDA in January 2014 for Ryanodex in the treatment of Malignant Hyperthermia which was granted a priority review and has a PDUFA date of July 22, 2014. Ryanodex for the treatment of MH has also received Orphan Drug designation.