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Unlabelled: Lercanidipine is a vasoselective dihydropyridine calcium antagonist which causes systemic vasodilation by blocking the influx of calcium ions through L-type calcium channels in cell membranes. It is a highly lipophilic drug and as such has a slower onset and longer duration of action than a number of other calcium antagonists. Preclinical evidence suggests that lercanidipine has antiatherogenic potential and it may also protect against end-organ damage. In well controlled clinical studies, once daily administration of lercanidipine 10 or 20mg effectively reduced blood pressure (BP) compared with placebo in patients with mild to moderate hypertension without affecting heart rate. Response rate (percentage of patients with diastolic BP < or =90mm Hg or reduced by > or =10mm Hg from baseline) ranged from 50 to 66% with lercanidipine 10 mg/day and up to 86% with lercanidipine 20 mg/day. The drug had a long duration of action: clinical measurements for diastolic BP yielded a trough/peak ratio of >0.8 for both lercanidipine dosages in 1 study. Comparative trials, either published in full or as abstracts, found lercanidipine 10mg once daily for > or =4 weeks to be at least as effective as atenolol 50mg once daily, candesartan cilexetil 16 mg/day, captopril 25mg twice daily, enalapril 20 mg/day, hydrochlorothiazide 12.5mg once daily, irbesartan 150 mg/day and slow release nifedipine 20mg twice daily in patients with mild to moderate hypertension. In addition, lercanidipine 20 mg/day was as effective as amlodipine 10 mg/day. Lercanidipine is effective in the treatment of elderly patients (aged 60 to 85 years) with mild to moderate essential hypertension and in those with isolated systolic hypertension. In addition, monotherapy with lercanidipine 20 or 40 mg/day has shown efficacy in patients with severe hypertension, and add-on therapy helped control BP in a large proportion of patients with severe hypertension not responding sufficiently to beta-blockers, diuretics or ACE inhibitors. Unpublished data indicate that the drug reduces blood pressure in patients with type 2 (non-insulin-dependent) diabetes mellitus, without adversely affecting glucose homeostasis. Lercanidipine was well tolerated in clinical trials, with most treatment-related adverse events typical of dihydropyridine calcium antagonists, namely headache, flushing, dizziness and ankle oedema., Conclusions: Lercanidipine is an effective and well tolerated once daily antihypertensive agent in patients with mild to moderate hypertension. In addition, the drug may reduce BP when used as monotherapy in patients with severe hypertension or when used adjunctively in patients with resistant hypertension. Importantly, lercanidipine appears to be at least as effective and well tolerated as other commonly used antihypertensive agents. The drug therefore represents a useful therapeutic option in the management of patients with hypertension and will be particularly useful in patients not responding to, or intolerant of, antihypertensive agents from other drug classes.

Unlabelled: Losartan is an orally active, nonpeptide, selective angiotensin subtype 1 (AT1) receptor antagonist. It provides a more specific and complete blockade of the actions of angiotensin II than renin or ACE inhibitors. Short term (up to 12 weeks' duration) clinical trials have shown losartan to be as effective at lowering blood pressure (BP) [causes a decrease in BP < or = 26/20 mm Hg] in elderly patients with hypertension as recommended dosages of captopril, atenolol, enalapril, felodipine and nifedipine. In patients with isolated systolic hypertension (ISH) the efficacy of losartan was similar to that of atenolol. The addition of hydrochlorothiazide to losartan therapy provides greater antihypertensive efficacy, equivalent to that seen with captopril plus hydrochlorothiazide. Preliminary evidence also indicates that losartan therapy contributes to the regression of left ventricular hypertrophy associated with chronic hypertension. Exercise capacity is increased by losartan in patients with either asymptomatic or symptomatic heart failure. Results from the Losartan Heart Failure Survival or ELITE II (Evaluation of Losartan in the Elderly II) study indicate that there was no statistically significant difference between losartan and captopril in reducing overall deaths or in reducing sudden cardiac death and/or resuscitated cardiac arrest in patients with heart failure. Other than ELITE II, little conclusive long term mortality and morbidity data exist for losartan. Additional long term trials to evaluate the survival benefits of losartan in elderly patients with hypertension, renal disease or after an acute myocardial infarction are currently in progress. In elderly patients with hypertension, the incidence of treatment-related adverse events associated with once daily losartan (alone or in combination with hydrochlorothiazide) [19 to 27%] was similar to felodipine (23%) and nifedipine (21%), however, losartan tended to be better tolerated than captopril (11 vs 16%). Losartan was also better tolerated than atenolol in patients with ISH (10.4 vs 23%). In patients with heart failure the renal tolerability of losartan was similar to that of captopril, but losartan was associated with a lower withdrawal rate because of adverse events. No dosage adjustment is required in elderly or in patients with mild to moderate renal dysfunction, and the risk of first-dose hypotension is low., Conclusions: comparative data have shown losartan to be as effective as other antihypertensive agents in the treatment of elderly patients with hypertension. Treatment with losartan is therefore an option for first-line therapy in all patients with hypertension, particularly those who are not well managed with or who are intolerant of their current therapy. Morbidity and mortality data from the Losartan Heart Failure Survival (ELITE II) study show that losartan has potential in the treatment of heart failure.

Low-dose drug combinations have been proposed in International Guidelines for use in patients with hypertension. The fixed low-dose combination of perindopril 2mg with indapamide 0.625mg combines an angiotensin converting enzyme (ACE) inhibitor with a non-thiazide diuretic. Coadministration of perindopril and indapamide did not have any clinically significant effects on the pharmacokinetic profile of either agent in healthy volunteers. In experimental models of hypertension, perindopril/indapamide restored endothelial function, improved microvascular density, reduced left ventricular and aortic hypertrophy, and reversed renal end-organ damage. Once daily oral perindopril 2mg/indapamide 0.625mg normalised blood pressure (BP) in 83.6% of elderly patients with essential hypertension (diastolic BP was reduced to < or =90mm Hg) and 81.7% of those with isolated systolic hypertension (systolic BP was reduced to <160mm Hg) after approximately 1 year of treatment. BP normalisation was sustained in 79.8% of patients throughout the study. Fixed low-dose perindopril/indapamide had a tolerability profile similar to that of placebo in clinical trials; most adverse events were of mild to moderate severity. Coadministration of the 2 agents reduced the incidence of hypokalaemia seen with indapamide alone.

Valsartan/hydrochlorothiazide (HCTZ) combines an angiotensin II AT1 receptor blocker with a thiazide diuretic to produce additive blood pressure reductions without major effects on heart rate. HCTZ did not significantly alter valsartan pharmacokinetics; during combination therapy, HCTZ pharmacokinetics differed from those seen with HCTZ monotherapy. In clinical trials in patients with essential hypertension, adding HCTZ 12.5 or 25 mg/day to valsartan 80 mg/day resulted in a greater blood pressure reduction than increasing the valsartan dosage from 80 to 160 mg/day. The valsartan/HCTZ combination was generally more effective than either drug given alone. Efficacy of the combination was maintained during up to 3 years of treatment. Valsartan/HCTZ was well tolerated in both short and long term trials. The most common adverse events were dizziness, headache and fatigue. The overall incidence of adverse events with the combination was similar to that with placebo. HCTZ-induced hypokalaemia was less common during combination therapy.

Unlabelled: Candesartan cilexetil is completely converted to the nonpeptide angiotensin II receptor blocker candesartan during absorption from the gastrointestinal tract. Candesartan selectively blocks and dissociates slowly from the angiotensin II subtype 1 (AT1) receptor which mediates most of the known activities of angiotensin II. When administered once daily, oral candesartan cilexetil 8 to 32 mg dose-dependently and effectively reduces blood pressure in patients with mild to moderate essential hypertension. In comparative studies, candesartan cilexetil 8 mg/day was as effective as usual therapeutic dosages of enalapril, losartan potassium, hydrochlorothiazide and amlodipine. One study showed candesartan cilexetil 16 mg/day to be more effective than losartan potassium 50 mg/day. Furthermore, the combination of candesartan cilexetil with either hydrochlorothiazide or amlodipine resulted in additive antihypertensive effects. Preliminary evidence suggests that the blood pressure-lowering effects of candesartan cilexetil are associated with the prevention or improvement of end-organ damage in patients with hypertension. However, this requires further confirmation in clinical studies. Candesartan cilexetil improves insulin sensitivity in patients with hypertension and does not affect glucose homeostasis or the serum lipid profile in those with coexisting type 2 (non-insulin-dependent) diabetes mellitus. Candesartan cilexetil is well tolerated in patients with hypertension. Pooled data indicate that the tolerability profile of the drug is not significantly different from that of placebo, with headache being the most commonly reported event. Adverse events are not dose related and are mostly mild to moderate in severity. Candesartan cilexetil is better tolerated than enalapril, primarily because of a reduced incidence of cough, and was not associated with the hypokalaemia or hyperuricaemia seen with hydrochlorothiazide in a study in patients aged > or = 75 years. The drug has an adverse events profile similar to that of losartan potassium in patients with mild to moderate hypertension., Conclusions: once daily candesartan cilexetil is effective and well tolerated when used once daily (as monotherapy or in combination with other antihypertensive agents) in patients with mild, moderate or severe hypertension. Initially, however, the drug is likely to be used as an alternative to other agents in patients not responding to or intolerant of their current drug therapy.

Eprosartan is a nonpeptide angiotensin II receptor antagonist which has a high affinity for the AT1 receptor subtype. When administered at dosages of 400 to 800 mg/day (once or twice daily) for 13 weeks to patients with mild to moderate essential hypertension, eprosartan significantly reduced blood pressure compared with placebo. Eprosartan was at least as effective as enalapril 10 to 40 mg/day in a dose-titration study in patients with severe hypertension. Eprosartan is generally well tolerated; clinical trials have shown the drug to have a tolerability profile similar to that of placebo. As with other angiotensin II receptor antagonists, it does not cause cough. Eprosartan is not metabolised by the cytochrome P450 system and therefore has a low potential for drug interactions.