Merck, 699852P-1MG, 3D-PHAD™

Vaccination is well-accepted as an effective method to prevent infections by mounting pathogen-specific immune responses prior to the infection. Usually, immunization with vaccine antigens alone is not able to induce robust or long-lasting immune responses — resulting in failure of protective immunity against infections. Thus, adjuvants are required to enhance cellular or humoral immune responses upon immunization. Because vaccine adjuvants using Lipid A have proven to be safe and effective in inducing Th-1 type immune responses to heterologous proteins in animal and human vaccines, Avanti developed Phosphorylated HexaAcyl Disaccharide (PHAD™), the first fully synthetic monophosphoryl Lipid A available for use as an adjuvant in human vaccines.