A New and Safe Delivery of Sildenafil Citrate Co-Evaporate Loaded Emulgels for the Cure of Certain Male Sexual Dysfunctions

Abstract

The present work focuses on the production of sildenafil co-evaporates loaded emulgels as topical dosage forms for the treatment of premature ejaculation and erectile dysfunction. Topical administration of sildenafil citrate (SILD) co-evaporates is expected to improve the bioavailability profile of the drug and to avoid the severe side effects accompanying the traditional SILD dosage forms, especially for prohibited cardiovascular cases. Firstly, the solubility of SILD was improved via solid dispersion via co-evaporation technique using PEG-5KDa and PVP-K90 as hydrophilic carriers. The modified co-evaporates were characterized by DSC, XRD, and solubility studies. Different emulgels, loaded with SILD co-evaporates, were formulated and characterized by different analyses including the viscosity, stability, spreadability, and in vitro release studies. Finally, the clinical activity of the chosen formula was accomplished via the application of the emulgels on volunteers suffering from erectile dysfunction. The results showed that the prepared SILD/PVP K90 of 1:2 w/w ratio exhibited the highest solubility and dissolution rate. All formulated emulgels exhibited good physicochemical properties. Especially, the emulgel formula composed of 2%w/v HPMC, loaded with SILD /PVP- K90, revealed the highest release rate. The release mechanism of SILD from emulgels fits with the Korsmeyer Peppas mechanism. The results of in vivo studies indicated a significant improvement of both IVLT and IIEF-5 parameters in mild to moderate ED, accompanied by PE. The modified SILD emulgel is an alternative promising and safe transdermal drug delivery system for the management and treatment of mild to moderate ED with PE.

Graphical Abstract