The aim of this study is to assess the quality of Valzan® tablet (160 mg, valsartan immediate release test formulation) by comparing its pharmacokinetic parameters with Diovan® tablet (160 mg, valsartan reference formulation). Valzan® tablets were prepared according to a dry granulation method (roll compaction). To assess the bioequivalence of Valzan® tablets a randomized, two-way, crossover, bioequivalence study was performed in 24 healthy male volunteers. The selected volunteers were divided into two groups of 12 subjects. One group was treated with the reference formulation (Diovan®) and the other one with the generic Valzan®, with a cross-over after the drug washout period of 14 days. Blood samples were collected at fixed time intervals and valsartan concentrations were determined by a validated HPLC assay method. The pharmacokinetic parameters AUC0–48, AUC0–∞, Cmax, Tmax, Ke and T1/2 were determined for both the tablets and were compared statistically to evaluate the bioequivalence between the two brands of valsartan, using the statistical model recommended by the FDA. The analysis of variance (ANOVA) did not show any significant difference between the two formulations and 90% confidence intervals (CI) fell within the acceptable range for bioequivalence. Based on this statistical evaluation it was concluded that the test tablets (Valzan®) is well formulated, since it exhibits pharmacokinetic profile comparable to the reference brand Diovan®.

BackgroundOrlistat is an irreversible inhibitor of the lipase enzyme that prevents trigylcerides from being digested, thereby inhibiting triglyceride hydrolysis and absorption. The resultant reduced calorie uptake enables a positive effect on weight control. Systemic absorption of the drug is, therefore, not necessary for its mode of action. An alternative in vitro study (pharmacodynamic) has been introduced for this drug, as in vivo bioavailability studies are irrelevant with regard to the achievement of the product’s intended purposes.ObjectivesTo develop a new validated high-performance liquid chromatography (HPLC) method for the analysis of orlistat and to assess the potency and equivalence of three orlistat formulations using the pharmacodynamic method as a surrogate indicator of pharmaceutical interchangeability.MethodsA new HPLC method was developed for the analysis and for the dissolution studies of orlistat in capsules. Pancreatic lipase activity was measured for three different capsule products: Orlislim®, Slimcare®, and Xenical®, G1, G2, and the brand, respectively. Porcine pancreatic lipase and p-nitrophenyl butyrate (PNPB) were placed in a pH 7.4 reaction buffer at 37°C, and substrate hydrolysis was monitored by measuring absorbance changes at 410 nm; this was repeated on six capsules of each product. The inhibition was expressed by the concentration of product, which inhibited 50% of the activity of pancreatic lipase (IC50).ResultsThe new analytical method was suitable for orlistat analysis. Values of IC50 from regression lines and equations were 6.14, 8.43, and 7.80 μg/mL for Orlislim®, Xenical®, and Slimcare®, respectively.ConclusionPharmacodynamic studies of lipase inhibition could be used to support in vitro dissolution, which demonstrates interchangeability between generic and branded orlistat capsules. Moreover, it could be suggested as an alternative tool to bioequivalence studies for orlistat oral products.

Purpose:The aim of this study was to formulate stable film-coated montelukast sodium (MS) tablets using Opadry® yellow 20A82938 (Montikast® tablets) and to evaluate their in vitro and in vivo release profile.Methods:MS core tablets were manufactured using a direct compression method. Opadry yellow 20A82938 aqueous coating dispersion was used as the film-coating material. Dissolution of the film-coated tablets was tested in 900 mL of 0.5% sodium lauryl sulfate solution and the bioequivalence of the tablets was tested by comparing them with a reference formulation – Singulair® tablets. In vitro–in vivo correlation was evaluated. The stability of the obtained film-coated tablets was evaluated according to International Conference on Harmonisation of Technical Requirements for Registration of Pharmaceuticals for Human Use guidelines.Results:The efficiency of the film coating was determined by subjecting the coated tablets to gastric pH and drug release was analyzed using high-performance liquid chromatography. The coated tablets had no obvious defects. MS release met the study criterion of not less than 80% dissolved after 30 minutes in 0.5% sodium lauryl sulfate solution. Statistical comparison of the main pharmacokinetic parameters clearly indicated no significant difference between test and reference in any of the calculated pharmacokinetic parameters. Level A correlation between in vitro drug release and in vivo absorption was found to be satisfactory.Conclusion:These findings suggest that aqueous film coating with Opadry yellow 20A82938 is an easy, reproducible, and economical approach for preparing stable MS film-coated tablets without affecting the drug-release characteristics.

Dissolution profiles were developed in three different pH media for the evaluation of valsartan/amlodipine (VS/AM) release from tablets. The selection of the most appropriate dissolution method was based on the calculated similarity (f 2 ) and dissimilarity (f 1 ) values. A new HPLC method was developed to quantify VS/AM in tablets. The method was validated in accordance with international guidelines and showed acceptable linearity, accuracy, precision, and selectivity. The system suitability results are within the acceptance criteria. The dissolution method (pH 6.8 phosphate buffer) was selected because it showed the highest f 2 and the lowest f 1 values for VS and AM among the other tested dissolution media. This method could be used for in vitro quality control and for performing in vitro-in vivo correlation (IVIVC) during the development of new generic tablets.

The aim of this study is to formulate and evaluate the quality of ciprofloxacin (CAS number: 85721-33-1) sustained release tablet (Ciprocare®XR) 1 000 mg ciprofloxacin (test formulation) by comparing its pharmacokinetic parameters with Cipro®XR sustained release tablet (reference formulation). For this purpose ciprofloxacin SR tablets were developed using the 2-layer method. To assess the quality of the produced sustained release tablets a randomized, 2-way, crossover, bioequivalence study was performed in 24 healthy, male volunteers. The selected Middle Eastern volunteers were divided into 2 groups of 12 subjects. One group was treated with the reference formulation and the other one with the test formulation, with a cross-over after a drug washout period of 7 days. Blood samples were collected at fixed time intervals and Ciprofloxacin concentrations were determined by a validated HPLC assay method. The pharmacokinetic parameters AUC0-48, AUC0-∞, Cmax, Tmax, Ke and T1/2 were determined for both sustained release tablets and were compared statistically to evaluate the bioequivalence between the 2 formulations of ciprofloxacin, using the statistical model recommended by the FDA. The analysis of variance (ANOVA) did not show any significant difference between the 2 formulations and 90% confidence intervals (CI) fell within the acceptable range for bioequivalence. According to the obtained results it was concluded that the test and reference formulations are bioequivalent, since they exhibit comparable pharmacokinetic parameters.