Innovative Buccal Nanofibers for Dual Delivery of Tadalafil and Dapoxetine for Erectile Dysfunction and Premature...

Background: Erectile dysfunction (ED) and premature ejaculation (PE) are prevalent conditions affecting men's sexual health, for which tadalafil and dapoxetine have shown promise in their treatment, respectively. Conventional oral dosage forms face limitations, including variable absorption and delayed onset of action. In this study, we developed electrospun nanofibers using polyvinylpyrrolidone for buccal drug delivery as an alternative dosage form to oral tablets. This route offers advantages such as easy administration, suitability for those with difficulty swallowing, particularly the elderly, and a rapid onset of action via the blood capillaries, which might improve bioavailability. Methods: PVP nanofibers loaded with tadalafil and dapoxetine were fabricated using a modified electrospinning procedure with the Spraybase system, where an 8% (w/v) PVP ethanol solution containing 1.5% dapoxetine and 0.5% tadalafil was electrospun under controlled conditions (800 µL/h flow rate, 15 cm distance, 0.55 mm needle, and 8-10 kV) to produce uniform fibers. Results: The morphology of the nanofibers was characterized using SEM, revealing smooth, uniform fibers with an average diameter of 218 ± 50 nm for drug-loaded nanofibers. This nanofibrous system also demonstrated ultra-rapid disintegration occurring within 4 ± 1 s and consistent drug loading and encapsulation efficiency for both drugs. The release profile showed a burst drug release after 15 min, which accounted for >45% for tadalafil and >50% for dapoxetine, followed by a sustained increment in the drug release that reached > 60% for tadalafil and >78% for dapoxetine after 30 min until a complete drug release (100%) for both drugs after 180 min. In vitro cytotoxicity studies on human dermal fibroblasts confirmed the safety of both medications, with cell viability exceeding 50%, at concentrations of 1.56 to 25 µg/mL for tadalafil and 4.69 to 9.38 µg/mL for dapoxetine after 24 and 48 h of incubation. Conclusions: These findings highlight the potential of PVP-based nanofibers as a novel buccal delivery system for the combined treatment of ED and PE.