Lipid 5, an amino lipid compound, demonstrates proficient mRNA delivery in rodent and primate models, with favorable pharmacokinetics and minimal toxicity.

Substituting the linoleic tail for a primary ester-containing lipid tail (Lipid 5) enhances expression and optimizes tissue clearance. Metabolite identification studies on Lipid 5 revealed that the initial metabolic step involves the hydrolysis of the primary ester[1].

The clearance of Lipid 5 and MC3 from various mouse tissues was evaluated following the administration of 0.05 mg/kg mRNA on days 1, 8, and 15 in CD-1 female mice. The liver and spleen exhibited the highest concentrations of Lipid 5, albeit at significantly lower levels than those of MC3. Detection of Lipid 5 also occurred in the plasma, lung, and kidney, but not in the heart[1].