Rib-X Pharmaceuticals
 Rib-X Pharmaceuticals founded in 2000 is an American privately held biopharmaceutical firm that focuses on the design and development of novel broad-spectrum antibiotics for the treatment of antibiotic-resistant infections in hospital and community settings. The company is located in New Haven Connecticut. Rib-X seeks to exploit expertise in the structural biology (particularly ribosomal structure) and molecular modeling to design new antibiotics.