Development of lamivudine liposomes by three-level factorial design approach for optimum entrapment and enhancing tissue targeting.

Aim: This work aimed to encapsulate lamivudine in liposomes for targeted delivery to HIV reservoirs and thereby reduce its side effects.Methods: The lamivudine liposomes were prepared by thin film hydration method using 32 factorial design and characterised for vesicle size, % drug entrapment efficiency, polydispersity index etc. Optimisation by graphical and numerical methods was carried out by fixing minimum and maximum limits for each response. In vivo plasma and tissue distribution of plain lamivudine and lamivudine encapsulated optimised liposomes were compared in rats.Results: The optimised liposomes displayed vesicle size 276.20 ± 13.36 nm, percent entrapment 60.20 ± 2.86% and PDI 0.291 ± 0.053. Compared to plain lamivudine, the liposomes were rapidly cleared from the plasma and displayed 10.97 ± 0.72 and 1.38 ± 0.52 fold accumulation in liver and spleen tissues respectively.Conclusions: Lamivudine encapsulated in liposomes remains in the body for a longer period of time with well distribution in tissues.