DEVELOPMENT AND CHARACTERIZATION OF NON-PROPELLANT FOAM INCORPORATED ACYCLOVIR FOR TREATMENT OF HERPES INFECTION

Objective: Herpes simplex virus (HSV) belongs to the herpes viridae family and primarily spreads through skin-to-skin contact. The study aimed to formulate topical anti-herpes non-propellant foam (NPF) incorporating acyclovir, offering a convenient alternative to conventional formulations. NPF is an optically transparent, thermodynamically stable, and light in consistency and evenly spreadable, thereby enhancing the permeation and poor permeability of acyclovir. Methods: The acyclovir nanoemulsion was formulated by the emulsification method and dispensed through a container, which, upon actuation, produced the foam. The NPF was characterized by globule size analysis, pH, viscosity, and foaming performances. The NPF was evaluated for the drug permeation ex vivo excised skin, and deposition, while cytocompatibility was determined in vitro in human keratinocytes, respectively. Results: The nanoemulsion had a globule size, pH, and polydispersity(PDI) of about 68.00 to 110.00 nm, pH of ~6.30 and a PDI of<0.200. The nanoemulsion viscosity was (⁓0.90 mPa. s, Spindle TSP-2, 20 rpm at 20 °C,), indicating the feasibility of expulsion from the container. Once actuated, the foam stability was 33.33% in 3 min, the expansion time was 100 sec, and density was 0.28g/ml, with a measured bubble size of 90.00 to 200.00 nm. The drug permeation of acyclovir was 411.147 per cm² (µg/ml) with a flux rate of 0.89µg/cm²/h, and a permeability coefficient of 0.1789 in ex vivo studies with drug deposition in the skin up to ~78%. In addition, cytocompatibility studies proved acyclovir NPF to be safe. Conclusion: The work suggests that NPF to be a new promising dosage form for topical application. The formulation when applied to the skin, instantly disappeared with no residue and was able to cover large body surfaces, presenting a no-touch application.