Related Experiment Videos
Endralazine - a new hydralazine-like antihypertensive with high systemic bioavailability
European Journal of Clinical Pharmacology
|January 1, 1983
Summary
Endralazine, a new antihypertensive, shows high bioavailability unaffected by acetylator status. This contrasts with hydralazine, suggesting potential clinical advantages for endralazine.
Area of Science:
- Pharmacology
- Clinical Pharmacology
- Drug Metabolism
Background:
- Hydralazine, a hydralazine-like antihypertensive, exhibits variable bioavailability influenced by acetylator phenotype.
- Understanding the pharmacokinetic profile of novel antihypertensives is crucial for optimizing therapeutic use.
Purpose of the Study:
- To evaluate the pharmacokinetic properties and bioavailability of endralazine (E) in normal volunteers.
- To compare the bioavailability of endralazine with that of hydralazine, particularly concerning acetylator phenotype.
Main Methods:
- Intravenous administration of endralazine (0.05 mg/kg) to 10 normal volunteers (5 slow and 5 fast acetylators).
- Plasma drug concentrations were analyzed using a 3-compartment model to determine pharmacokinetic parameters.
- Oral bioavailability of endralazine was assessed using AUC data from a previous study.
Main Results:
- Endralazine demonstrated high systemic bioavailability, ranging from 73.5-99.1%, indicating near-complete absorption with minimal first-pass metabolism.
- Bioavailability of endralazine was not significantly affected by dose size or acetylator phenotype.
- In contrast, hydralazine showed lower bioavailability (<40%) and significantly higher levels in slow acetylators compared to fast acetylators.
Conclusions:
- Endralazine possesses high and consistent bioavailability, independent of acetylator phenotype.
- These favorable pharmacokinetic properties suggest potential clinical advantages for endralazine over hydralazine in hypertension management.