BALLERUP, Denmark--(BUSINESS WIRE)--LEO Pharma launches a new, safe drug, ATryn®, for preventing blood clots in patients. It concerns patients who, due to a genetic defect, cannot produce enough of the protein antithrombin III or whose antithrombin III is not sufficiently efficient. Antithrombin is a protein that is a key part of managing the coagulation process in the bloodstream.