Synthetic Biologics, Inc., a clinical-stage company, develops therapeutics to treat gastrointestinal (GI) diseases in the United States. Its lead product candidates include SYN-004 that has completed Phase II clinical trial designed to degrade commonly used intravenous beta-lactam antibiotics in GI tract for the prevention of microbiome damage, clostridium difficile infection (CDI), overgrowth of pathogenic organisms, the emergence of antimicrobial resistance (AMR), and acute graft-versus-host-disease in allogeneic hematopoietic cell transplant recipients; and SYN-020, a recombinant oral formulation for the enzyme intestinal alkaline phosphatase to treat both local GI and systemic diseases. The company also develops clinical stage products, such as SYN-006 and SYN-007 for the prevention of CDI, overgrowth of pathogenic organisms, and AMR; and SYN-005 for the prevention and treatment of pertussis. Synthetic Biologics, Inc. has collaborations with Intrexon Corporation, The University of Texas at Austin, and Cedars-Sinai Medical Center; and a clinical trial agreement with Washington University School of Medicine in St. Louis to conduct a Phase 1b/2a clinical trial of SYN-004. The company is headquartered in Rockville, Maryland.