As the South Korean epidemic of Middle East Respiratory Syndrome continues unabated, researchers have raced to find treatments for the deadly virus, which has killed more than 400 people since it was first discovered three years ago in Saudi Arabia. Now, scientists at the University of Maryland School of Medicine and Regeneron Pharmaceuticals, Inc., have discovered and validated two therapeutics that show early promise in preventing and treating the disease, which can cause severe respiratory symptoms, and has a death rate of 40 percent.