Efficacy and safety of losartan 100 mg or losartan 100 mg plus hydrochlorothiazide 25 mg in the treatment of patients with essential arterial hypertension and CV risk factors: observational, prospective study in primary care

A Comparative Study of the Management of Stage 2 hypertension by Combined therapy with Losartan, Amlodipine and Hydrochlorothiazide

BACKGROUND

The most effective and accurate treatment of hypertensive patients reduces cardiovascular events and improves the quality of life.

OBJECTIVE

This study compared the efficacy and safety of combined (combination therapy) with an angiotensin-receptor blocker (ARB) a calcium-channel blocker (CCB) (Losartan / Amloidipine 50/10mg) vs maximal combination doses of ARB with hydrochlorothiazide (Losartan /HCTZ 100/25 mg) and maximal combination doses of CCB with HCTZ (Amlodipine /HCTZ 10/25 mg) in the management of stage 2 hypertension.

METHODS

This randomized clinical trial (RTC) comprised 478 hypertensive patients with mean age 50.5±5.21 years, and took place between January 2010 and December 2011 in Vasei Hospital clinic in Sabzevar. Antihypertensive drugs were washed out after 5 days of discontinuation of drugs and the patients with mean blood pressure in sitting position ≥ 160 and <200 mmHg in systole and ≥ 100 and <110 mmHg in diastole were randomized into three groups: Losartan / Amlodipine 50/10 mg (n =164) , Losartan / HCTZ 100/25 mg (n =155) and Amlodipine / HCTZ 10/25 mg (n =159). The end point was reaching the blood pressure below 140/90 within 56 days of treatment in each group.

RESULTS

There was a significant difference in systolic blood pressure reductions between treatment groups (P<0.001) and also there was a significant difference between groups in reducing diastolic blood pressure (P<0.01). The highest systolic and diastolic blood pressure reduction respectively was found in Amlodipine/losartane and losartane/HTCZ group. The ANCOVA analysis revealed that only treatment regimen had a significant effect (P=0.01) and other factor including Age, Gender, Diabetes Mellitus, Smoking and High serum cholesterol didn't have significant effect on blood pressure reduction.

CONCLUSION

ARB/CCB combination therapy reduced blood pressure more effectively than the maximal doses of ARB or CCB with HCTZ in stage 2 hypertensive patients within this period of study.

Captopril and losartan for mitigation of renal injury caused by single-dose total-body irradiation

It is known that angiotensin converting enzyme inhibitors (ACEIs) and angiotensin II type-1 receptor blockers (ARBs) can be used to mitigate radiation-induced renal injury. However, for a variety of reasons, these previous results are not directly applicable to the development of agents for the mitigation of injuries caused by terrorism-related radiation exposure. As part of an effort to develop an animal model that would fit the requirements of the U.S. Food and Drug Administration (FDA) "Animal Efficacy Rule", we designed new studies which used an FDA-approved ACEI (captopril) or an FDA-approved ARB (losartan, Cozaar®) started 10 days after a single total-body irradiation (TBI) at drug doses that are equivalent (on a g/m(2)/day basis) to the doses prescribed to humans. Captopril and losartan were equally effective as mitigators, with DMFs of 1.23 and 1.21, respectively, for delaying renal failure. These studies show that radiation nephropathy in a realistic rodent model can be mitigated with relevant doses of FDA-approved agents. This lays the necessary groundwork for pivotal rodent studies under the FDA Animal Efficacy Rule and provides an outline of how the FDA-required large-animal studies could be designed.