A double-blind comparison of perindopril and hydrochlorothiazide-amiloride in mild to moderate essential hypertension

Perindopril: an updated review of its use in hypertension

Perindopril erbumine (perindopril) is a prodrug ester of perindoprilat, an angiotensin converting enzyme (ACE) inhibitor. Perindopril 4 to 8 mg once daily significantly reduces supine systolic blood pressure (SBP) and diastolic blood pressure (DBP) from baseline values in hypertensive patients. These reductions are maintained for at least 24 hours, as evidenced by trough/peak ratios of >50%. Vascular abnormalities associated with hypertension were improved or normalised during perindopril treatment. Perindopril 4 to 8 mg once daily significantly decreased carotid-femoral aortic pulse wave velocity (PWV), improved arterial compliance, reduced left ventricular mass index and, in patients with recent cerebral ischaemia and/or stroke, preserved cerebral blood flow despite significantly reducing SBP and DBP. Further research is needed to establish the significance of promising results showing that reductions in aortic PWV were associated with reduced mortality in patients with end-stage renal failure, a third of whom received perindopril. Response rates (numbers of patients with supine DBP < or = 90 mm Hg) were significantly higher with perindopril 4 to 8 mg once daily (67 to 80%) than with captopril 25 to 50 mg twice daily (44 to 57%) in 3 randomised double-blind trials. In other clinical trials, the antihypertensive effects of perindopril were similar to those of other ACE inhibitors (including enalapril) and calcium-channel antagonists. Combination treatment with perindopril and an antihypertensive agent from another treatment class provided additional benefits, either as first-line treatment or in patients failing to respond to monotherapy. Perindopril monotherapy was also effective in the elderly and in patients with hypertension and concomitant disease. Perindopril has a similar adverse event profile to that of other ACE inhibitors; cough is the most common event reported during treatment, and is also the most common adverse event responsible for treatment withdrawal.

CONCLUSIONS

Perindopril is a well tolerated ACE inhibitor that is significantly better than captopril (in terms of response rates) in the treatment of hypertension, and as effective as other ACE inhibitors. Perindopril appears to reverse some of the vascular abnormalities associated with hypertension, including arterial stiffness and left ventricular hypertrophy, although further research is needed to confirm promising results regarding its ability to decrease associated cardiovascular morbidity and mortality. Results from ongoing studies will help confirm the place of perindopril in the treatment of hypertension; currently, it is an effective and well tolerated treatment for patients with mild to moderate essential hypertension.

Efficacy of perindopril in the treatment of systemic hypertension

The angiotensin-converting enzyme inhibitor, perindopril erbumine, has been approved for use in the United States only recently but has been studied extensively worldwide over the last decade. Placebo-controlled trials in a wide range of patients with hypertension, including the elderly, those with isolated systolic hypertension, and those with concomitant diseases such as hyperlipidemia, diabetes, cardiac arrhythmia, peripheral arterial occlusive disease, nephropathy with proteinuria, and chronic obstructive pulmonary disease, have shown that perindopril is highly effective in lowering both systolic and diastolic blood pressure (BP). Studies in which BP has been monitored for 24-hour intervals show that perindopril (1) has a gradual onset of action, (2) provides smooth BP control over its once-daily dosing interval, (3) has a trough-peak ratio of about 1, and (4) maintains its antihypertensive efficacy despite missed doses. Perindopril increases arterial compliance and reverses left ventricular hypertrophy in hypertensive patients. Both of these effects are at least partly independent of its ability to lower BP. Perindopril is safe and well tolerated in patients with hypertension. Rates of adverse events and discontinuation because of such events are low.

Dosage considerations with perindopril for systemic hypertension

Perindopril erbumine is a once-daily angiotensin-converting enzyme (ACE) inhibitor that effectively lowers systolic and diastolic blood pressure (BP) in patients with mild-to-moderate hypertension. Converted from the prodrug ester perindopril, the active diacid perindoprilat is distributed rapidly and extensively, primarily to tissues with high ACE activity. Its ability to lower BP is comparable to or better than that of other antihypertensive agents, both of its own class and other classes, and its trough-peak ratio is consistently between 75% and 100%, translating into 24 hours of true efficacy per dose. First-dose hypotension caused by an initial acute BP depression occurs less frequently with perindopril than with other ACE inhibitors, an advantage in volume-contracted patients and those whose BP is angiotensin II dependent, such as patients with congestive heart failure. A missed-dose study showed that most of the antihypertensive effect of perindopril remains for 24 to 48 hours after dosing, a characteristic that confers protection to patients who miss a dose. Perindopril improves the distensibility and compliance of large and small arteries, which are compromised in hypertension, and can effect vascular remodeling by a mechanism independent of BP lowering. The clinical implications of these effects are being investigated in large trials. Perindopril is well tolerated in the elderly, and combination therapy with a diuretic was shown to yield significant additional BP reduction. Perindoprilat is cleared renally; dosage should be adjusted in patients with renal impairment.

Selection of drugs to treat gastro-oesophageal reflux disease: the role of drug interactions

Gastro-oesophageal reflux disease is probably the most common acid-peptic disease in Western countries, and the successful treatment of mild to moderate disease with pharmacotherapy has become commonplace. A large number of effective drugs are now available, and so the decision-making process for physicians increasingly relies on considerations other than pure efficacy. Cost, adverse effects and drug interactions have therefore become important, particularly in the most vulnerable patients - children, the elderly and patients who are ill and are taking medications that may influence the efficacy of antireflux therapy. Important drug interactions with antacids include the prevention of the absorption of antibacterials such as tetracycline, azithromycin and quinolones. H2 antagonists, proton pump inhibitors and prokinetic agents undergo metabolism by the cytochrome P450 (CYP) system present in the liver and gastrointestinal tract. Cimetidine is an inhibitor of CYP3A and it may cause significant interactions with drugs of narrow therapeutic range and low bioavailability that are metabolised by these enzymes. The gastroparietal proton pump inhibitors lansoprazole, omeprazole and pantoprazole are all primarily metabolised by a genetically polymorphic enzyme, CYP2C19, that is absent from approximately 3% of Caucasians and 20% of Asians. These drugs may also interact with CYP3A, but to a lesser extent. Interactions with prokinetic agents carry the greatest potential for harm. Metoclopramide is a dopamine antagonist that may cause extrapyramidal effects when administered alone at high concentrations, or when coadministered with antipsychotic agents such as haloperidol or phenothiazines. Cisapride is clearly able to prolong the electrocardiographic QT interval and cause lethal ventricular arrhythmias when its metabolism is slowed by interaction with inhibitors of CYP3A, such as erythromycin, ketoconazole or itraconazole.

Long-term acceptability of perindopril: European multicenter trial on 856 patients

The acceptability of perindopril in the long-term treatment of patients with mild to severe essential hypertension was assessed in a large European multicenter trial including 856 patients. Diastolic blood pressure (DBP) at inclusion was 95-125 mm Hg after 1 month of placebo. Normalization of blood pressure was defined as a DBP less than or equal to 90 mm Hg. Treatment was started with perindopril 4 mg once daily and increased when necessary to 8 mg daily. If DBP was not controlled, a second drug (hydrochlorothiazide) and finally a third drug were added. After 1 year of treatment in all 690 evaluable patients, supine systolic and diastolic blood pressure decreased by 29 mm Hg (from 172 +/- 1 to 143 +/- 1 mm Hg, p less than 0.001) and 19 mm Hg (from 105 +/- 1 to 86 +/- 1 mm Hg, p less than 0.001), respectively. Perindopril monotherapy normalized blood pressure in 55% of patients and total percentage of normalization was 78%. The overall incidence of withdrawals for side effects was 6.8%, the most common side effect being cough (2.2%). The most frequent complaints reported were cough (7.0%), headache (5.6%), asthenia (5.1%), mood and/or sleep disturbance (5.1%), and dizziness (3.2%). The small changes observed in hematologic and biochemical parameters were not clinically relevant.

Perindopril. A review of its pharmacological properties and therapeutic use in cardiovascular disorders

Perindopril is a long acting angiotensin converting enzyme (ACE) inhibitor, which displays similar pharmacodynamic properties to other agents in this class. In common with enalapril, it is also a prodrug. After absorption, perindopril is hydrolysed to the active metabolite, perindoprilat, and with once daily administration adequate 24-hour inhibition of ACE is obtained. Perindopril 4 to 8mg once daily is usually effective for blood pressure control in patients with mild to moderate essential hypertension. Those patients who do not respond adequately to monotherapy with perindopril usually respond with the addition of a second agent, such as a thiazide diuretic. General practice trials indicate that perindopril is at least as effective and as well tolerated as usual therapeutic dosages of captopril, atenolol or hydrochlorothiazide plus amiloride in mild to moderate essential hypertension. Preliminary results indicate that perindopril may also be effective in patients with severe hypertension or congestive heart failure. Perindopril is generally well tolerated and has an adverse effect profile similar to that of other ACE inhibitors. It further clinical experience confirms initial findings, perindopril is likely to represent a useful alternative to other members of the ACE inhibitor class in all grades of hypertension and congestive heart failure.