Development and pharmacokinetic evaluation of osmotically controlled drug delivery system of Valganciclovir HCl for potential application in treatment of CMV retinitis
Abstract Valganciclovir HCl (VGH) is the widely used drug for the treatment of Cytomegalovirus (CMV) retinitis infection with an induction dose of 900mg twice a day and a maintenance dose of 900mg. This required dose of the drug also leads to multiple side effects due to repeated administration. The research was highlighted to develop, formulate, optimize and evaluate Single-Core Osmotic Pump (SCOP) tablet of VGH with the dose of 450mg to reduce dosing frequency and associated side effects. . The decrease in dose also minimize the hepatic and nephrotic load. The optimized batch of formulation was subjected to comparative in vitro and in vivo evaluation. The tablet core composition is the primary influencer of the drug delivery fraction in a zero-order, whereas the membrane characteristics control the drug release rate. In-vivo pharmacokinetic studies revealed that the newly developed osmotic formulation has controlled zero-order release for 24 hours with a single dose of 450mg while the marketed formulation requires twice administration within 24 hours to maintain the plasma concentration in the therapeutic window. The developed formulation can be the promising option for the treatment of CMV retinitis with the minimum dose and dosing frequency.