Spray-dried tenofovir alafenamide-chitosan nanoparticles loaded oleogels as a long-acting injectable depot system of anti-HIV drug

The development of suitable drug delivery systems for prolonged action against HIV receives great attention in recent research. Herein, a long-acting injectable (LAI) of Tenofovir alafenamide-chitosan polymeric nanoparticles loaded oleogels developed with sesame oil and ethyl cellulose for prolonged release of the drug is reported for the first time. The research resulted with unique long-acting parenteral formulation for chronic anti-retroviral therapy, based on our experimental in-vitro and ex-vivo studies. The chitosan nanoparticles with 49 % drug content were produced through the spray-drying technique and characterized for their size (106-540 nm) and the other physico-chemical features through SEM, FT-IR, XRD, TGA, and DSC. The ethyl cellulose and sesame oil oleogels were developed through a heat-cool process by incorporating the drug-loaded chitosan nanoparticles. The oleogels exhibited extended release (56 %) of the drug for 16 days, which could be prolonged further to achieve the maximum drug release. Also, the ex-vivo permeation studies of the nanoparticles loaded oleogels demonstrated about 10-fold decrease in the flux and the permeation of the drug due to prolonged release of the drug across dual barriers of chitosan nanoparticles and ethyl cellulose gel matrix. The result provided proof-of-evidence that the developed Tenofovir alafenamide-chitosan polymeric nanoparticles loaded with ethyl cellulose oleogels could be potentially used as the long-acting injectable system for the treatment of patients infected with HIV/AIDS.