Novel Insight into Potential Leishmanicidal Activities of Transdermal Patches of Nigella Sativa: Formulation Development, Physical Characterizations, and In vitro/In vivo Assays

Cutaneous Leishmaniasis (CL) is the most common type of Leishmaniasis, which annually affects 1.5 million people worldwide. About 90% of cases are reported from countries such as Iran, Afghanistan, Pakistan, Iraq, and Saudi Arabia. The purpose of the present study was to fabricate transdermal patches of Nigella sativa (NS), characterize, and to check its in vitro/in vivo anti-Lieshmanial activity. Hydroalcoholic extract was analyzed for preliminary phytochemicals. Five formulations of transdermal patches (NS1, NS2, NS3, NS4, and NS5) were prepared by solvent evaporation method. The optimized formulation NS5 was characterized for Fourier transform-infrared spectroscopy (FTIR), smoothness, brittleness, clarity, thickness, folding endurance, uniformity of weight, percent moisture content, in vitro drug release, release kinetics, ex vivo drug permeation, and in vitro anti-Lieshmanial activity. In vivo anti-Lieshmanial activity was assessed in 30 patients (n = 30) suffering from CL. The FTIR studies showed no incompatibility among the active extract and polymers. In vitro anti-Lieshmanial assay was 194.6% +/- 1.88% as compared with standard drug (p > 0.05) and in vivo anti-Lieshmanial activity was 75%. The drug release after 24 h was 87.0% +/- 0.94% in NS5, which showed non-Fickian diffusion mechanism while drug permeation across rabbit skin after 24 h was up to 80.0% +/- 0.91%. The results concluded that problems related to the parenteral medications used for Lieshmanial treatment can be managed by applying extract of NS seeds in the form of transdermal patch.