First-line treatment of hypertension: from monotherapy to fixed low-dose combination therapy

Bridging strategies for drug combinations in pediatric indications

Concurrent prescription of different drugs is common and is often necessary in many pediatric indications. A randomized concentration-controlled trial (RCCT) is proposed for pediatric studies in which drug combinations are used. The aim of our investigation was to show the relevance of flexible designs for accurate dose selection in such cases. We used the combination of atovaquone (ATV) and proguanil (PGN) as a paradigm to illustrate our approach. Pharmacokinetic models were developed for ATV and PGN using data pertaining to adults. The median area under the curve (AUC) in adults was considered the target exposure for bridging purposes. A pediatric population was simulated according to scenarios in which clearance varied from 20 to 100% of the reference adult values or allometrically correlated with body weight (BW). Doses were subsequently adapted according to the individual AUC estimates. Our results show that adaptive protocols are critical for accurate dose selection when evaluating drug combinations in children, ensuring that target exposure is achieved with respect to both active moieties in each individual patient.

Hypertension management in 2002: where have we been? where might we be going?

The term "blood pressure" was coined almost 300 years ago by the man who first measured it, the Reverend Stephen Hales of England. However, our understanding of the pathogenesis and consequences of hypertension, as well as the available treatments for it, have remained greatly limited and inadequate until only the past 30 years. Starting in 1977, reports from the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of Hypertension (JNC) have provided regular updates on developments in hypertension management, and have set guidelines for the diagnosis and treatment of hypertension. More than 20 years ago, the JNC stratified blood pressure (BP) levels into categories of mild, moderate, and severe (later renamed stages 1, 2, and 3, respectively). A stepped-care approach to hypertension therapy was originally recommended. With each revised JNC report, there was a reduction in target BP and a growing recognition of the importance of high-normal BP and isolated systolic hypertension. The sixth and most current report of the Joint National Committee, JNC VI, emphasizes treatment of comorbidities of hypertension, sets a lower BP goal (<130/85 mm Hg) for high-risk patients-eg, those with diabetes or renal disease-than for those with uncomplicated hypertension (<140/90 mm Hg), and places a greater emphasis on disease prevention. For the future, the current trend toward lower BP goals suggests that more effective and better tolerated antihypertensive therapies will be needed. Multiple antihypertensive agents used concomitantly will likely be needed to control elevated levels of BP in the majority of hypertensive patients.

Safety and tolerability of eprosartan in combination with hydrochlorothiazide

The ideal antihypertensive drug should be effective in reducing blood pressure, but have a low incidence of adverse effects. Angiotensin II receptor blockers, such as eprosartan, are as effective as ACE inhibitors in reducing blood pressure, but lack the main adverse effect of ACE inhibitors, namely cough. Eprosartan has been shown to be well tolerated with a placebo-like adverse-effect profile. When given as monotherapy it is effective in reducing blood pressure; however, some patients require additional blood pressure control, which may be provided by combination therapy. Indeed, the combination of eprosartan and the thiazide diuretic hydrochlorothiazide has been shown to be effective in further reducing blood pressure in patients not optimally responding to eprosartan monotherapy. This article reviews the safety and tolerability of eprosartan in combination with hydrochlorothiazide from 17 studies of 1899 patients with hypertension and normotensive volunteers. Of these studies, four were controlled with patients receiving a fixed-dose combination, six were long-term, open-label, and another four were controlled studies with hydrochlorothiazide being given to eprosartan non-responders. The other three studies included healthy subjects receiving the combination of eprosartan and hydrochlorothiazide. There was a high completion rate in all studies evaluated. Most of the patients receiving eprosartan 600mg in combination with hydrochlorothiazide 12.5mg daily completed the studies, which supports acceptance of this combination therapy by patients. The most frequently reported adverse events in these combination studies were headache, dizziness, myalgia, and upper respiratory tract infection in patients with hypertension. The majority of adverse events were mild to moderate in intensity, and were not considered to be related to study treatment. The adverse event that was more common in patients receiving combination therapy compared with those receiving monotherapy was dizziness. This adverse event may be due to hydrochlorothiazide as it has previously been observed in patients taking thiazide diuretics. In healthy volunteers, the most frequently reported adverse events were headache, dizziness, and upper respiratory tract infection. However, none of these adverse events were considered related to study medication. In summary, the combination of eprosartan/hydrochlorothiazide is well tolerated, both as short- and long-term therapy, with most adverse events occurring early. The most frequent adverse events were headache, dizziness, and upper respiratory infection, which would be expected based on the safety profile of each of the components. Therefore, the combination of eprosartan with hydrochlorothiazide can be effectively and safely used in patients not adequately responding to eprosartan monotherapy.