The Studies On Stavudine Extended-release Pellets Capsules

In this paper, Stavudine (STVD) was selected as an anti-AIDS model drug to prepare extended-release pellets capsules and the drug release behavior and mechanism from extended-release pellets capsules were studied. At last, the pharmacokinetic study of STVD extended-relese pellets capsules was performed in six beagle dogs.In the formulation and technique study of STVD extended-release pellets capsules, Blank pellets, Poloxammer 188, and HPMC were used to make the drug pellet; Kollicoat SR 30D and Propylene Glycol(PG) were selected as the coating materials ; Purified water was employed as the coating medium. The effects of many factors on the release behavior of STVD from extended-release pellets capsules were investigated, including the formulation of the drug pellet core and the coating membrane, the arts of preparing extended-release pellets capsules and the drug release condition in vitro.Based on the single-factor and factor-screening experiments, the amount of HPMC and the ratio of coating weight were selected as the causal factors. The formulation optimized according to orthogonal experiment design was proved to have the similar release behavior in vitro as the extended-release tablets. The investigation of STVD release mechanism from extended-release pellets capsules showed that the drug release was primarily controlled by the coated film-membrane.With the commercial immediated-release capsule as the reference, the pharmacokinetic study of self-prepared STVD extended-release pellets capsules was performed in six Beagle dogs. HPLC method was employed to detect the drug concentration in plasma after oral administered with single dose by the crossover design . The pharmacokinetic parameters of the test and...