Theriva Biologics, Inc. is a clinical stage company, which engages in the development of therapeutics to preserve the microbiome to protect and restore the health of patients. Its product portfolio includes SYN-020 and SYN-004. SYN-020 is intended to prevent the antibiotic-mediated microbiome damage, C. difficile infections (CDI), overgrowth of pathogenic organisms, the emergence of antimicrobial resistance (AMR) and acute graft-versus-host disease (aGVHD) in allogeneic HCT recipients. SYN-004 is designed to protect the gut microbiome from the effects of certain commonly used intravenous (IV) antibiotics for the prevention of C. difficile infection, antibiotic-associated diarrhea, and the emergence of antimicrobial resistance. The company was founded by Steven H. Kanzer in January 2001 and is headquartered in Rockville, MD.