Lipid III-45

Lipid III-45 is a synthetic ionizable lipid characterized by symmetric branched lipid tails and a propanolamine polar head group, designed specifically for lipid nanoparticle (LNP) formulations to encapsulate and deliver mRNA therapeutics.[7] It facilitates endosomal escape and cytosolic release of mRNA payloads, enabling applications in vaccines and gene therapies, such as those for infectious diseases or genetic disorders. Unlike natural lipids that serve structural or signaling roles in cell membranes, Lipid III-45 has no endogenous biological function and is not a receptor, enzyme, or transporter.[1][2][5] No drugs directly target it as a therapeutic molecule, and it plays no role in disease pathology; instead, it is an excipient to enhance drug delivery efficacy. Challenges include optimizing LNP stability and minimizing off-target effects, but it is not associated with patient biomarkers or safety concerns tied to biological modulation.[7][11]

Other names

Lipid III-45ionizable lipid for mRNA encapsulation