Pharmacokinetics and Bioequivalence of Dienogest in Healthy Bangladeshi Female Volunteers: An Open-Label, Single-Dose, Randomized, Two-Way Crossover Study

Background: Dienogest is a potential treatment for pelvic pain associated with endometriosis, a condition of significant concern in gynaecology. The current study was conducted as a crossover-randomized bioequivalence assessment of two oral Dienogest 2 mg formulations, aiming to provide valuable insights for healthcare professionals and researchers in this field. Objective: The primary aim of this research was to evaluate and compare the pharmacokinetic characteristics of Dienogest 2 mg tablets. Dinogest (Dienogest 2 mg) tablets, manufactured by Nuvista Pharma Limited in Bangladesh, and Visanne (Dienogest 2 mg) tablets, manufactured by Bayer Pharma in Germany, were the test and reference formulations, respectively. Materials and Method: The study was an open-label, balanced, randomized, two treatments, two sequences, two periods, two-way crossover, laboratory blind, single oral dose bioequivalence study conducted in healthy adult females under fasting conditions. The study was carried out on 13 healthy, non-pregnant female subjects, and all the subjects completed both study periods with a 15-day washout in between. Randomization was used to assign the test and reference formulations to the subjects. Following each oral administration, a series of blood samples were obtained at different time intervals from pre-dose to 72 hours post-dose and analyzed for Dienogest concentrations using a validated bio-analytical method. A standard non-compartmental model was used to analyze the pharmacokinetic parameters. The primary pharmacokinetic parameters were peak plasma drug concentration (Cmax), the area under the plasma concentration-time curve from time zero to time t (AUC0–t), and AUC from t = 0 to infinity (AUC0–∞). The other PK parameters included time to reach Cmax (Tmax), terminal elimination rate constant (Kel), and half-life (t1/2). Result: The ratios and 90% CI for the geometric mean test/reference were 95.53% (86.70% - 105.26%) for Cmax, 101.75% (95.42% - 108.49%) for AUC0−t, and 101.54% (95.59%% - 107.87%) for AUC0−∞. The formulations were bioequivalent since the 90% CIs for the geometric mean test/reference ratios were 80% to 125%, according to the predetermined range of US Food and Drug Administration (FDA) requirements. Conclusion: This single-dose investigation shows that the Dienogest test and reference formulations exhibited a rate and degree of absorption that met the regulatory requirements for bioequivalence.

Bioequivalence Study of Two Formulations of Telmisartan 40 mg Tablets in Healthy Adult Bangladeshi Subjects under Fasting Conditions

Background: Telmisartan is a highly variable drug which is used to treat hypertension. This study compared to compare the bioavailability of two 40 mg Telmisartan tablets in adult and healthy Bangladeshi subjects. Materials and Method: This study was open label, randomized, laboratory blind, single dose, three periods, two treatments, three-sequence, partial-replicate, crossover and comparative oral bioavailability study. In this study, 18 Bangladeshi subjects were enrolled and 17 subjects were completed. Serial blood samples were collected up to 96 hours following drug administration. By using Liquid Chromatography Mass Spectrometry (LC-MS/MS) method, plasma concentrations of Telmisartan were determined. Results: The two formulations of Telmisartan were considered bioequivalent if 90% Confidence Interval (CI) fall within the range of 80.00% - 125.00% for AUC parameters and reference-scaled-average bioequivalence of 69.84% - 143.19% for Cmax. The 90% Confidence Interval for Cmax, AUC0-t & AUC0-∞ was found 84.88% - 107.79%, 89.76% - 109.55%, and 91.20% - 114.52%, respectively. Conclusion: According to rate and extent of absorption with the single dose of Reference Product (R): Micardis® 40 mg Tablet, under fasting conditions, a single dose of Telmisartan 40 mg Tablet is bioequivalent.