Analysis Of Relative Bioavailability Of Simvastatin Drugs On An Empty Stomach And After Meals

High generic drug quality:one of the five major goals of China’s drug review and approval system reform.Accelerating the quality consistency evaluation of generic drugs can improve the quality of generic drugs,realize the clinical substitution of original drugs,and reduce the overall drug price level.Simvastatin is a lipid-lowering drug that can reduce levels of cholesterol,low-density lipoprotein cholesterol,and very low-density lipoprotein cholesterol.Therefore,it is important to study the degree and speed of simvastatin absorption in the human body by eating.Bioavailability analysis is an important part of the consistency evaluation of generic drugs,and traditional bioavailability studies mainly compare the bioequivalence analysis between generic drugs and innovator drugs,but ignore the relative bioavailability of generic drugs in fasting and postprandial situations.In this paper,the bioavailability of generic drugs of domestic simvastatin was studied,and the pharmacokinetic index data of 20mg simvastatin developed by different domestic manufacturers were used for analysis.Firstly,the development background of generic drugs in China is introduced,the research background and significance of drug bioavailability are discussed,and the remarkable results achieved by domestic and foreign scholars in Bayesian statistics and drug bioavailability are summarized.This paper then describes Bayesian statistics and the theoretical knowledge of relative bioavailability.Thirdly,the empirical analysis of the domestic simvastatin data was carried out,two Bayesian models were constructed,the MCMC algorithm and Gibbs sampling were used to fill in the missing data of simvastatin,the posterior distribution and posterior estimate of the parameters to be estimated were obtained,and the convergence of the parameter estimation was judged and analyzed.Then,the obtained posterior parameter values were analyzed using the postprandialfasting mean ratio and its confidence interval method,and the bioavailability size of simvastatin produced by different manufacturers was compared.Finally,the results showed that the drug bioavailability of the domestic generic drug simvastatin after meals was higher than that taken on an empty stomach,and taking after meals had the greatest effect on the peak concentration of Cmax in the pharmacokinetic parameter.The availability of simvastatin drugs produced by different manufacturers is different,among which the drug simvastatin produced by Shanghai Xinyi Vientiane Pharmaceutical Co.,Ltd.has the highest relative bioavailability.