Single dose bioequivalence study of alpha-methyldopa tablet formulations using a modified HPLC method.
Hadi Valizadeh1, Mahboob Nemati, Somayeh Hallaj-Nezhadi
1Drug Applied Research Center, Tabriz University of Medical Sciences, Tabriz, Iran.
Arzneimittel-Forschung
|December 4, 2010
Summary
A new methyldopa tablet formulation was found to be bioequivalent to the reference formulation. This study utilized a validated HPLC method to compare bioavailability in healthy male subjects.
Area of Science:
- Pharmacokinetics
- Analytical Chemistry
- Pharmaceutical Sciences
Background:
- Methyldopa is a medication used to treat hypertension.
- Bioavailability studies are crucial for generic drug development.
- Assessing the bioequivalence of different formulations ensures therapeutic equivalence.
Purpose of the Study:
- To compare the bioavailability of a new methyldopa tablet formulation against a reference formulation.
- To establish bioequivalence between the test and reference methyldopa products.
- To validate a modified High-Performance Liquid Chromatography (HPLC) method for alpha-methyldopa analysis.
Main Methods:
- An open-label, single-dose, randomized, cross-over study was conducted in 12 healthy male subjects.
- Subjects received either the test or reference 250-mg methyldopa tablet under fasting conditions.
- Blood samples were analyzed using a validated, modified HPLC method to determine pharmacokinetic parameters (Cmax, AUC).
Main Results:
- The modified HPLC method demonstrated acceptable validation criteria for specificity, accuracy, precision, and sensitivity.
- Pharmacokinetic parameters (Cmax, AUC0-infinity) showed no statistically significant differences between the test and reference formulations.
- The 90% confidence intervals for the mean test/reference ratios fell within the established bioequivalence range (92.48-115.94 for Cmax, 88.82-101.13 for AUC0-infinity).
Conclusions:
- The developed HPLC method is rapid, reliable, and suitable for analyzing alpha-methyldopa in human plasma.
- The new methyldopa tablet formulation is bioequivalent to the reference formulation.
- The findings support the use of the new methyldopa formulation as a therapeutically equivalent alternative.
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