Singapore Drugs Database

Indication

For the treatment of mild to moderate essential hypertension, mild to moderate congestive heart failure, and to reduce the cardiovascular risk of individuals with hypertension or post-myocardial infarction and stable coronary disease.

Mechanism of Action

There are two isoforms of ACE: the somatic isoform, which exists as a glycoprotein comprised of a single polypeptide chain of 1277; and the testicular isoform, which has a lower molecular mass and is thought to play a role in sperm maturation and binding of sperm to the oviduct epithelium. Somatic ACE has two functionally active domains, N and C, which arise from tandem gene duplication. Although the two domains have high sequence similarity, they play distinct physiological roles. The C-domain is predominantly involved in blood pressure regulation while the N-domain plays a role in hematopoietic stem cell differentiation and proliferation. ACE inhibitors bind to and inhibit the activity of both domains, but have much greater affinity for and inhibitory activity against the C-domain. Perindoprilat, the active metabolite of perindopril, competes with ATI for binding to ACE and inhibits and enzymatic proteolysis of ATI to ATII. Decreasing ATII levels in the body decreases blood pressure by inhibiting the pressor effects of ATII as described in the Pharmacology section above. Perindopril also causes an increase in plasma renin activity likely due to a loss of feedback inhibition mediated by ATII on the release of renin and/or stimulation of reflex mechanisms via baroreceptors.

Pharmacokinetics

Absorption

Rapidly absorbed with peak plasma concentrations occurring approximately 1 hour after oral administration. Bioavailability is 65-75%. Following absorption, perindopril is hydrolyzed to perindoprilat, which has an average bioavailability of 20%. The rate and extent of absorption is unaffected by food. However, food decreases the extent of biotransformation to peridoprilat and reduces its bioavailability by 35%.

Distribution

Metabolism

Extensively metabolized, with only 4-12% of the dose recovered in urine following oral administration. Six metabolites have been identified: perindoprilat, perindopril glucuronide, perindoprilat glucuronide, a perindopril lactam, and two perindoprilat lactams. Only perindoprilat is pharmacologically active. Peridoprilat and perindoprilat glucuronide are the two main circulating metabolites.

Elimination

Clearance

* 219 - 362 mL/min [oral administration]

Toxicity

The most likely symptom of overdose is severe hypotension. The most common adverse effects observed in controlled clinical trials include cough, digestive symptoms, fatigue, headache, and dizziness.

Active Ingredient/Synonyms

(2S,3AS,7as)-1-[(2S)-2-{[(2S)-1-ethoxy-1-oxopentan-2-yl]amino}propanoyl]octahydro-1H-indole-2-carboxylic acid | Perindoprilum | Perindopril |