3D(6-acyl)-PHAD™

Current adjuvant systems used in vaccine research and development include Glucopyranosyl Lipid Adjuvants (GLA-LSQ, GLA-SE, GLA-AF) which were developed by Access to Advance Health Institute, second group of systems - Army Liposome Formulations (ALF, ALFA, ALFQ) were developed by Walter Reed Army Institute of Research, one more group of Adjuvant Systems (AS01, AS04) is the only one in the marketed vaccines and were developed by GSK.

*this content is derived from a broad spectrum of research papers

Lipopolysaccharide (LPS) is a major component of the outer membrane of Gram-negative bacteria. It is contributing to the structural integrity of the bacteria and protecting the membrane from certain kinds of chemical attacks. When bacteria breach our initial defence barriers it induces a strong immune system response targeting several PRRs (pattern recognition receptors) including TLR2 and TLR4. LPS is a potent activator of the immune system and pyrogen (agent that causes fever). In severe cases, LPS can play a role in causing septic shock. 

Monophosporyl Lipid A (MPLA) is bacterial derived detoxified version of Salmonella minnesota LPS. MPLA specifically targets Toll-like receptor 4 (TLR4) on immune cells. Activation of TLR4 triggers a cascade of signaling pathways that lead to the activation of innate immune responses. 

PHADs (Phosphorylated Hexa Acyl Disaccharides) were developed as a synthetic alternative to the bacterial-derived MPLA, given its desirable vaccine tailored profile of low reactogenicity and high efficacy.