Abstract
Valsartan (CAS 137862-53-4) is an antihypertensive drug belonging to the family of
angiotensin II receptor antagonists acting at the AT1 receptor, which mediates all known effects of angiotensin II on the cardiovascular
system. In the present study, the pharmacokinetic parameters of two oral formulations
of valsartan tablets were compared in a randomized, single oral dose, two-treatment
crossover design in 24 healthy male volunteers under fasting conditions. After an
overnight fast, the volunteers received 80 mg valsartan. Blood samples were collected
up to 48 h and drug concentrations were determined by a reverse-phase HPLC method
with fluorescence detection. Various pharmacokinetic parameters were determined from
the plasma concentration-time curves of both formulations. The obtained values for
test and reference products were 3 067.7 ± 1 281.7 and 3 304.3 ± 1 196.4 ng/ml for
Cmax; 17 834.4 ± 7 083.8 and 18319.1 ± 7 800.7 ng · h/ml for AUC0–48; 18825.7 ± 7 553.2 and 19 172.2 ± 8 307.2 ng · h/ml for AUC0–∞, respectively. The 90% confidence intervals obtained by analysis of variance were
86.84–100.87% for Cmax and 93.43–115.54% for AUC0–t, which are within the acceptance range of 80–125%. Therefore it can be concluded
that both products are bioequivalent in terms of rate and extent of drug absorption
and therefore interchangeable.
Key words
Angiotensin II receptor antagonist - Antihypertensive - CAS 137862-53-4 - Valsartan,
bioavailability, bioequivalence