HIV, in situ gel, microbicide, pre-exposure prophylaxis, tenofovir disoproxil fumarate.
Abstract
Pre-exposure prophylaxis (PrEP) is one of the best preventive strategies in protection against HIV/AIDS. The present research approach is development of novel topical thermosensitive mucoadhesive in situ gel for intravaginal use. Tenofovir disoproxil fumarate (TDF) has been loaded in the formulation and cold method was followed to prepare the various formulations. Pluronic® F-127 and Pluronic® F-68 polymers were used. Hydroxypropylmethyl cellulose (HPMC E50) was added in some of the formulations as a mucoadhesive and viscosity enhancing polymer. Drug-polymer compatibility studies were carried out prior to formulation. The formulations were evaluated for clarity, gelation temperature (tgel), pH, rheology, drug content, spreadability, force of mucoadhesion, retention time, in vitro release, release kinetics and curve fitting. Formulation A3 was found as the most suitable formulation based on the evaluation parameters, as it exhibited the desired properties. The release kinetics studies suggested that A3 followed Higuchi model. Formulation A3 was subjected to accelerated stability studies at 40 oC ± 2 oC /75% RH ± 5% RH for 6 months. The results indicated that it remained stable for 6 months. The study concludes that due to the ease of application, mucoadhesion and prolonged contact time, patient compliance may be improved and better protection achieved.
