IntroductionAtorvastatin (AVS) is lipid-lowering agent, which is selective, competitive inhibitor of 3-hydroxy-3-methylglutaryl-coenzyme. A reductase which catalyzes the conversion of HMG-CoA to mevalonate, which is a rate limiting step in cholesterol biosynthesis. AVS decreases the levels of low-density lipoprotein (bad cholesterol) and triglycerides in the blood, while enhancing the levels of highdensity lipoprotein (good cholesterol). 1-2 The empirical formula of AVS calcium is (C33H34FN2O5)2Ca2+·3H 2 O with a molecular weight of 1209.42, as shown in Figure 1. AVS is widely used to treat high cholesterol, to lower the risk of heart attack, myocardial infarction, angina, stroke, and other heart complications in people with type II diabetes and coronary heart disease. The dosage range of AVS is 10-80mg once a daily as a single dose with or without food at any time of the day. [3][4] The starting recommended dose of AVS is 10-20mg once daily, rapidly absorbed after oral administration. The half-life is approximately 12h, extensively metabolized to ortho-and para-hydroxylated derivatives and various beta-oxidation products (cytochrome P450 3A4) in the liver (hepatic metabolism) and a small amount of the drug metabolates from urine, elimination is mainly through bile. 5-7 Oral dosage forms are safest and commonest route of drug administration. The efficacy of the dosage systems can be assured when its quality is reliable. 8 The efficacy of pharmaceutical dosage systems usually depends on their formulation and manufacturing techniques, therefore the quality of dosage system may vary. [9][10][11] In this research to assess the quality/bioequivalence study of four different AVS marketed tablets (10mg) currently available in Asir region, kingdom of Saudi Arabia. They were chosen for the study to survey AVS tablets in terms of product quality and price difference in the various brands. This research was carried out for general organoleptic test, structural defects, and comparative evaluation of official and non-official quality control test such as thickness, diameter, friability, hardness, drug content uniformity, weight variation, in vitro dissolution studies, kinetic release of drug, and statistical analysis of AVS marketed/commercially available tablets, which is very useful for pharmacists and health care professionals in order to determine the interchangeability.
Materials and methods
MaterialsFour different marketed brands/samples of Atorvastatin calcium tablets (10mg) were purchased from community pharmacy (drug store) in Abha city, Asir region. The samples were properly checked for their drug dose, manufacturing license number, batch numbers, manufacturing and expiry dates. They were coded as A-D the details of all samples were shown in Table 1. The other solvents and chemical used in the study was analytical grade.
MethodsThese are the following official and non-official quality control tests 12 are carried out during the study of different marketed brands of AVS.
Uniformity of weightAccording to USP, Twenty (...