Arsanis, Inc.
A clinical-stage biopharmaceutical company that developed monoclonal antibodies—lab-made proteins engineered to latch onto specific germs—to fight serious infections where antibiotics fall short. Founded in 2010 in Vienna by scientists Eszter Nagy and Tillman Gerngross, it created ASN100, an experimental treatment meant to prevent staph pneumonia in high-risk hospital patients. After disappointing trial results, it merged with X4 Pharmaceuticals in 2019 and carried on under that name.