The Efficacy and Safety of Initial Use of Irbesartan/Hydrochlorothiazide Fixed-Dose Combination in Hypertensive Patients With and Without High Cardiovascular Risk

Olmesartan ameliorates chemically-induced ulcerative colitis in rats via modulating NFκB and Nrf-2/HO-1 signaling crosstalk

Alteration in the expression pattern of Nrf-2 and NFκB has been reported in ulcerative colitis (UC) in which functional crosstalk between these two critical pathways has been suggested. The ameliorative potential of the AT1R blocker olmesartan (OLM) on oxidative stress and inflammatory cytokines has received considerable attention in recent years. Acetic acid (AA)-induced UC demonstrates close resemblance to human UC regarding histopathological features and cytokine profile and is associated with local intense immune response, oxidative stress and release of inflammatory cytokines. Therefore, The effect of OLM (1, 5 and 10 mg/kg) administered orally to rats subjected to intra-rectal instillation of 2 ml of 3% AA in saline solution is investigated. The study revealed that OLM ameliorated colon injury and inflammatory signs as visualized by histopathological examination. Levels of colon IL-6, TNF-α, IL-1β, TGF-β, and serum CRP were down-regulated, while the level of colon IL-10 was up-regulated. In a dose-dependent manner, OLM suppressed AA-induced neutrophils accumulation and improved colon anti-oxidant defense machinery. Also, OLM repressed the Bax:BCL-2 ratio and caspase3 expression. The mechanism of these protective effects was found to lay behind its ability to down-regulate gene expression and inhibit phosphorylation and nuclear translocation of p65 subunits. On the other hand, OLM up-regulated gene expression of Nrf-2 and HO-1. In conclusion, our data show that OLM is an Nrf2 activator, NFkB inhibitor and apoptosis inhibitor in an experimental model of ulcerative colitis. Overall, the study indicates that OLM shows promise as a potential therapy for the treatment of human inflammatory bowel diseases.

Efficacy and safety of a fixed combination of irbesartan/hydrochlorothiazide in Chinese patients with moderate to severe hypertension

Background and Objectives

In a multi-center, single-arm, prospective study, we investigated the efficacy and safety of the fixed irbesartan/hydrochlorothiazide combination in Chinese patients with moderate to severe hypertension.

Methods

Eligible patients were aged 18–75 years, with a blood pressure of 160–199 mmHg systolic or 100–119 mmHg diastolic during a 1-week wash-out phase off antihypertensive medication. The enrolled patients started antihypertensive treatment with irbesartan/hydrochlorothiazide 150 mg/12.5 mg once daily, with the possible addition of irbesartan 150 mg once daily and up-titration to irbesartan/hydrochlorothiazide 300 mg/25 mg once daily at 4 and 8 weeks of follow-up, respectively. The primary efficacy variable was the goal blood pressure-attaining rate at 12 weeks of follow-up (<140/90 mmHg, or <130/80 mmHg in patients with diabetes mellitus).

Results

In the intention-to-treat analysis (n = 501) at 12 weeks of follow-up, the goal blood pressure-attaining rate was 57.3 %, and the mean change in blood pressure from baseline was 27.8 mmHg [95 % confidence interval (CI) 26.4–29.1 mmHg; p < 0.001] systolic and 13.5 mmHg (95 % CI 12.6–14.4 mmHg; p < 0.001) diastolic. Similar findings were observed in the per-protocol analysis (n = 449). The prevalence of microalbuminuria and left ventricular hypertrophy significantly (p ≤ 0.01) decreased from 33.4 % (150/449) and 50.4 % (215/427) at baseline to 23.4 % (105/447) and 41.3 % (176/427) at the end of follow-up, respectively. Four patients (2.0 %) reported a serious adverse event.

Conclusion

The fixed irbesartan/hydrochlorothiazide combination may control blood pressure to the target level in about 60 % of Chinese patients with moderate to severe hypertension, with an acceptable safety profile.

Efficacy and safety of irbesartan/HCTZ in severe hypertension according to cardiometabolic factors

This post hoc analysis of a 7-week, randomized, double-blind trial evaluated the efficacy and safety of initial irbesartan/hydrochlorothiazide treatment in 468 patients with severe, uncontrolled, hypertension (diastolic blood pressure [DBP] > or =100 mm Hg) at high cardiovascular risk. Systolic blood pressure (SBP)/DBP reductions ranged from 28.0 to 42.9/22.9 to 27.2 mm Hg in patients with obesity, diabetes, baseline SBP > or =180 mm Hg, and in the elderly. Blood pressure control to <140/90 mm Hg in the age and obesity subgroups ranged from 32.1% to 39.2% while control to <130/80 mm Hg in patients with diabetes was 11.5%. After 1 week of therapy, 72.5% of patients no longer had SBP > or =180 mm Hg; by 7 weeks, 51.3% had SBP 140 to 159 mm Hg and 26.5% had SBP <140 mm Hg. Treatment was well tolerated regardless of the subgroup. No excess of prespecified events was noted. Thus, initial treatment with irbesartan/hydrochlorothiazide was rapidly effective in high-risk, difficult-to-treat, severely hypertensive patients.

Significance of initial blood pressure and comorbidity for the efficacy of a fixed combination of an angiotensin receptor blocker and hydrochlorothiazide in clinical practice

Background:

Two-thirds of all patients with arterial hypertension need drug combinations to achieve blood pressure (BP) goals. Fixed combinations have high efficacy and result in high patient compliance. 300 mg irbesartan plus 25 mg hydrochlorothiazide (HCTZ) has been investigated only in clinical trials but not in daily practice.

Methods:

A multicenter, noninterventional, noncontrolled observational study with 8123 patients seen by 1604 physicians in daily practice. BP reduction (office measurements), co-morbid disease and tolerability were documented over a 6-month observational period.

Results:

At mean baseline BP of 161 ± 15/94 ± 10 mmHg, administering of fixed combination resulted in a substantial BP reduction averaging 28 ± 15/14 ± 10 mmHg (P < 0.001). Decrease of systolic BP ran parallel with increasing systolic baseline BP (Spearman’s Rho −0.731; P < 0.0001; diastolic BP vs diastolic baseline BP Rho 0.740; P < 0.0001), independent from patient characteristics (age, obesity, diabetes or nephropathy) but enhanced with short history of hypertension (P < 0.0001 vs long history), prior beta blockers (P = 0.001 vs prior angiotensin receptor blockers [ARBs]), prior calcium channel blockers (P = 0.046 vs prior ARBs) and no prior medication (P = 0.012 vs prior ARBs). High compliance (>98%) and low incidence of adverse events (0.66%) were documented.

Conclusions:

The fixed combination of 300 mg irbesartan with 25 mg HCTZ was efficacious and tolerable in an unselected patient population in primary care.

Fixed combination of irbesartan and hydrochlorothiazide in the management of hypertension

Approximately 25% of the adult population worldwide is hypertensive and thus at risk of cardiovascular morbidity and mortality. Despite the availability of many antihypertensive drugs, at least 50% of patients do not achieve blood pressure (BP) targets and thus remain at increased cardiovascular risk. Fixed-dose (FD) irbesartan/hydrochlorothiazide (HCTZ) is an antihypertensive combination therapy approved for the treatment of patients whose BP is not adequately controlled on monotherapy and for initial treatment of patients likely to need multiple drugs to achieve their BP goal. The efficacy and tolerability of FD irbesartan/HCTZ has been demonstrated in both patient populations in large multicenter studies. In patients failing antihypertensive monotherapy, FD irbesartan/HCTZ (150/12.5 mg) has been shown to be more effective than FD valsartan/HCTZ (80/12.5 mg) and at least comparable to FD losartan/HCTZ (50/12.5 mg). In patients with moderate or severe hypertension receiving FD irbesartan/HCTZ as initial therapy, this combination achieved more rapid BP reductions compared with irbesartan monotherapy and enabled a greater proportion of patients with severe hypertension to achieve their BP target. FD irbesartan/HCTZ is thus a valuable addition to the clinician’s armamentarium for the management of hypertension and should help more patients achieve their BP target.

Evaluation of recent fixed-dose combination therapies in the management of hypertension

PURPOSE OF REVIEW

Control of hypertension remains sub-optimal with only half of patients achieving adequate control. The Seventh Report of the Joint National Committee on the Prevention, Detection, Evaluation, and Treatment of High Blood Pressure guidelines recommend initial use of two antihypertensive agents in patients with stage 2 hypertension. This review discusses the drug combinations that have additive effects and those that do not provide additional benefit while increasing the adverse events.

RECENT FINDINGS

Results from late-breaking trials have shown that combinations of a calcium channel blocker and angiotensin-converting enzyme inhibitor are superior to a diuretic with an angiotensin-converting enzyme inhibitor for reducing cardiovascular events. Additionally, in patients with vascular disease with relatively 'controlled' blood pressure at baseline, the combination of an angiotensin-converting enzyme inhibitor and angiotensin receptor blocker did not reduce cardiovascular endpoints compared with either monotherapy and modestly increased the incidence of adverse effects.

SUMMARY

Combination therapy of antihypertensive agents (e.g. angiotensin-converting enzyme inhibitor/calcium channel blocker, angiotensin-converting enzyme inhibitor/diuretics, and angiotensin receptor blocker/diuretics) as initial therapy in stage 2 hypertension can lead to markedly improved blood pressure control in patients compared with monotherapeutic regimens.

Initial combination therapy for rapid and effective control of moderate and severe hypertension

Moderate (grade 2) and severe (grade 3) hypertension are important public health problems associated with high cardiovascular risk. Blood pressure (BP) control becomes more difficult to achieve as hypertension progresses. Therefore, early and effective treatment is essential to prevent hypertensive urgencies and emergencies and reduce cardiovascular risk. Currently, less than 50% of patients being treated for moderate or severe hypertension in the United States achieve their BP goal as recommended by treatment guidelines. This review examines the cardiovascular risk and physician inertia associated with moderate and severe hypertension, and concludes that increased use of initial combination therapy can overcome many of the barriers to effective BP control. Furthermore, initial combination therapy with a renin-angiotensin system (RAS) inhibitor and diuretic has the potential to rapidly and effectively reduce BP across a range of baseline BPs, with a comparable adverse event profile to monotherapy.