STOPPING at the CAPPP of good HOPE

Valsartan in the treatment of hypertension

Valsartan is a widely used, efficacious and very well-tolerated antihypertensive agent. By specifically blocking the action of angiotensin II on the angiotensin Type 1 receptor, valsartan reduces unwanted effects of angiotensin II, such as aldosterone, vasopressin and endothelin secretion, vasoconstriction, diuresis, endothelial cell hyperplasia, mitogenesis, induction of growth factors and production of collagen. Valsartan has a simple pharmacokinetic profile and requires no metabolism to become active. The dose-related efficacy of valsartan has been clearly demonstrated and the tolerability profile is similar to placebo. Clinical trials in elderly patients show good efficacy and high responder rates with the same doses as in younger patients. Valsartan is available as 80-, 160- and 320-mg tablets, and also in the same doses in combination with hydrochlorothiazide, 12.5 or 25 mg. Availability varies between countries. Beyond the reduction of blood pressure, valsartan is indicated for use in several countries in patients with heart failure and in patients post myocardial infarction, based on the results of the large-scale Valsartan Heart Failure Trial and VALsartan In Acute myocardial iNfarcTion trials. Valsartan has also been shown, in the Valsartan Antihypertensive Long-term Evaluation trial, to reduce the risk of developing new-onset diabetes in hypertensive patients at high risk of cardiac events.

The case for blood pressure control in risk groups

Hypertension rarely occurs in isolation, and many hypertensives have additional risk factors for cardiovascular disease in addition to elevated blood pressure. Each patient's cardiovascular disease risk profile should be determined individually, and the treatment approach tailored to each case. Cardiovascular disease risk factors and high blood pressure are closely linked, suggesting that the ideal treatment should not only lower blood pressure, but also effectively lower overall risk. This is likely to require more than one drug, and one of the most effective and safe combinations is that of an angiotensin receptor blocker with a diuretic. The completion of one of the most important trials undertaken to explore risk factors and anti-hypertensive treatment, the Valsartan long-term evaluation trial (VALUE), will certainly enhance understanding for the role of combination treatment in high-risk patients, as well as contribute to the design of rational treatments for blood pressure control.

Hypertension therapy: mixing, matching, and meeting targets

The inappropriate control of hypertension is a public health problem worldwide. It is notable that although there are several causes for this situation, lack of effective pharmacotherapy is not among them. It has long been known that combinations of antihypertensive drugs are highly effective in most patients; the problem is implementing treatment recommendation guidelines into clinical practice with the most effective and best tolerated therapies. The latest guidelines on therapies for hypertension from the World Health Organization/International Society of Hypertension, the Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure (US), and the European Societies of Hypertension and Cardiology consistently emphasize this need of combination treatments in a large part of the hypertensive patient population. This review focuses on the combination of one of the oldest drugs, thiazide diuretics, with one of the youngest, angiotensin-receptor blockers, and analyzes the available literature regarding potential applications in specific populations. This represents one of the most widely used, rational and effective combination therapies, combining excellent control of blood pressure with unequalled tolerability. In addition, angiotensin-receptor blocker/diuretic combinations may have cardiovascular benefits beyond those from blood pressure lowering itself.

Valsartan/hydrochlorothiazide is effective in hypertensive patients inadequately controlled by valsartan monotherapy

OBJECTIVE

This double-blind parallel-group randomized trial compared the efficacy and safety of fixed combination valsartan 160 mg/hydrochlorothiazide 12.5 mg (Val 160/HCTZ 12.5) once daily (o.d.) and Val 160/hydrochlorothiazide 25 mg (Val 160/HCTZ 25) o.d. vs Val 160 o.d. monotherapy in patients with mild-to-moderate essential hypertension not adequately controlled with valsartan monotherapy.

METHOD

A total of 2002 patients whose BP was inadequately controlled with 4 weeks of Val 160 mg o.d. monotherapy were randomized to treatment for 8 weeks with Val 160 (n = 666), Val 160/HCTZ 12.5 (n = 670) or Val 160/HCTZ 25 (n = 666).

RESULTS

Active treatment significantly reduced BP in all groups over the 12 weeks of the study (p < 0.001). The greatest reductions were achieved with Val 160/HCTZ 25. Reductions were 10.8, 12.8 and 14.2 mmHg (sitting diastolic blood pressure) and 15.7, 19.4 and 21.8 mmHg (sitting systolic blood pressure), for the Val 160, Val 160/HCTZ 12.5 and Val 160/HCTZ 25 groups, respectively. Responder rates were high in all groups (49%, 62% and 68%). In elderly patients (> or = 65 years) responder rates of 70% were achieved with Val 160/HCTZ 25. All treatments were well tolerated, in all patient groups.

CONCLUSIONS

The combination of Val 160 plus HCTZ 12.5 or HCTZ 25 provides effective and well-tolerated treatment in patients inadequately controlled after 4 weeks of monotherapy. In elderly patients a responder rate of 70% was achieved with Val 160/HCTZ 25.