Combination therapy in the management of hypertension: focus on angiotensin receptor blockers combined with diuretics

Comparative Effectiveness of Angiotensin II Receptor Blockers in Patients With Hypertension in Japan - Systematic Review and Network Meta-Analysis

Background: Angiotensin II receptor blockers (ARBs) are widely used for the management of hypertension in Japan; however, comparative efficacy data within the ARB drug class remain limited. Methods and Results: This systematic literature review identified randomized controlled trials (RCT) indexed in PubMed and Ichushi in Japanese patients with hypertension receiving ARB monotherapy (azilsartan, candesartan cilexetil, irbesartan, losartan potassium, olmesartan medoxomil, telmisartan, valsartan) in at least 1 arm. Of 763 RCTs identified, 77 met the eligibility criteria; of which, 37 reported mean change in systolic blood pressure (SBP) and diastolic blood pressure (DBP) from baseline in the office setting and were used to construct the network. A fixed-effects model (FEM) showed the effect of each drug vs. the reference, azilsartan. Using the FEM, the mean (95% credible interval) change from baseline in SBP/DBP for candesartan cilexetil, irbesartan, losartan potassium, olmesartan medoxomil, telmisartan, and valsartan was 3.8 (2.9-4.8)/2.6 (2.0-3.1), 4.8 (2.0-7.5)/3.7 (1.8-5.6), 3.0 (0.8-5.1)/1.9 (0.5-3.3), 3.2 (1.2-5.1)/2.7 (1.3-4.1), 3.2 (0.8-5.6)/2.0 (0.3-3.6), and 3.1 (1.1-5.1)/2.4 (1.1-3.8) mmHg, respectively. Conclusions: The results of this meta-analysis provide evidence that azilsartan has a more favorable efficacy profile than the other ARBs in reducing SBP and DBP.

Fimasartan versus perindopril with and without diuretics in the treatment of elderly patients with essential hypertension (Fimasartan in the Senior Subjects (FITNESS)): study protocol for a randomized controlled trial

Background

Hypertension is an important risk factor for cardiovascular disease, even in the elderly. Fimasartan is a new non-peptide angiotensin II receptor blocker with a selective type I receptor blocking effect. The objective of this study is to confirm the safety and the non-inferiority of the blood pressure–lowering effect of fimasartan compared with those of perindopril, which has been proven safe and effective in elderly patients with hypertension.

Methods

This is a randomized, double-blind, active-controlled, two-parallel group, optional-titration, multicenter, phase 3 study comparing the efficacy and safety of fimasartan and perindopril arginine. The study population consists of individuals 70 years old or older with essential hypertension. The primary outcome will be a change in sitting systolic blood pressure from baseline after the administration of the investigational product for 8 weeks. The secondary outcomes will be a change in sitting diastolic blood pressure from baseline and changes in sitting systolic blood pressure and diastolic blood pressure from baseline after the administration of the investigational product for 4, 16, and 24 weeks. The sample size will be 119 subjects for each group to confer enough power to test for the primary outcome.

Discussion

Research to confirm the efficacy and safety of a new medicine compared with those of previously proven anti-hypertensive drugs is beneficial to guide physicians in the selection of therapeutic agents. If it is confirmed that the new drug is not inferior to the existing drug, the drug will be considered as an option in the treatment of hypertension in elderly patients.

Trial registration

ClinicalTrials.gov Identifier: NCT03246555, registered on July 25, 2017.

Electronic supplementary material

The online version of this article (10.1186/s13063-019-3466-5) contains supplementary material, which is available to authorized users.

Modeling of the pharmacokinetic/pharmacodynamic interaction between irbesartan and hydrochlorothiazide in normotensive subjects

PURPOSE

To investigate the pharmacokinetic/pharmacodynamic (PK/PD) interaction between irbesartan (IRB) and hydrochlorothiazide (HCT) in normotensive subjects.

METHODS

A three-way crossover study was used. Serial drug concentrations and drug effects, including systolic and diastolic blood pressure and heart rate were monitored after administration of irbesartan and hydrochlorothiazide alone and in combination. The data were fitted to a PK/PD model and the parameters for irbesartan and hydrochlorothiazide when administered alone and in combination were compared.

RESULTS

The plasma profiles for irbesartan and hydrochlorothiazide followed the two-compartment model after a single dose. The PK parameters of irbesartan were not affected by hydrochlorothiazide; however irbesartan decreased the hydrochlorothiazide AUC by 25% and increased its clearance by 25%. There were no significant changes in heart rate after each drug alone or in combination. Irbesartan plus hydrochlorothiazide had a greater blood pressure lowering effect compared with irbesartan alone, despite the unchanged irbesartan PK. The relationship between irbesartan plasma concentration and its effects plotted in chronological order showed anticlockwise hysteresis. The PD parameter estimates for the effect of irbesartan on systolic blood pressure, when administered with hydrochlorothiazide were significantly different from those when irbesartan was administered alone. This was manifested by a 25% increase in Emax , and a 40% decrease in EC50 , suggesting a synergistic blood pressure lowering effect for the combination. While parameter estimates for the effect of irbesartan on diastolic blood pressure were changed by hydrochlorothiazide, the differences were only significant for EC50 .

CONCLUSION

A limited potential for clinically significant interactions between irbesartan and hydrochlorothiazide at the given doses were observed; therefore, no dosage adjustments were recommended for either drug when used together. (ClinicalTrials.gov Identifier NCT01858610)

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.

Effectiveness of hydrochlorothiazide in combination with telmisartan and olmesartan in adults with moderate hypertension not controlled with monotherapy: a prospective, randomized, open-label, blinded end point (PROBE), parallel-arm study

BACKGROUND

The potential combinations of antihypertensive agents are many, and making rational choices depends on the characteristics of each drug and on their complementary mechanisms of action.

OBJECTIVE

The aim of this study was to evaluate the effectiveness of adding hydrochlorothiazide (HCTZ) 12.5 mg to olmesartan 20 mg or telmisartan 80 mg on blood pressure (BP) in patients with moderate hypertension.

METHODS

Consecutive outpatients at the Centro per l'Ipertensione e la Fisiopatologia Cardiovascolare, University of Pavia, Pavia, Italy, of both sexes aged 39 to 75 years were considered eligible for enrollment if they had a sitting diastolic BP (DBP) ->99 mm Hg and <110 mm Hg at the end of an initial 2-week washout period. Patients were random- ized to olmesartan 20 mg QD or telmisartan 80 mg QD according to a prospective, open-label, blinded end point, parallel-arm design. After 8 weeks of monotherapy, patients whose BP was not controlled (DBP ->90 mm Hg) received HCTZ 12.5 mg QD for 8 additional weeks. Clinical and ambulatory BPs were measured at the end of the washout period and at the end of both treatment periods. Adverse events (AEs) were recorded from spontaneous reports and direct inquiry from investigators.

RESULTS

One hundred forty-five patients, all of whom were white, were recruited for the study. After the initial washout period, 13 patients did not meet the inclusion criteria and 6 refused to continue. A total of 126 white patients (69 men, 57 women; mean [SD] age, 60.2 [11.6] years) were randomized to receive monotherapy. Of these, 35 patients (56%) in the olmesartan group and 33 (52%) in the telmisartan group had previously received antihypertensive therapy. At the end of monotherapy, the 52 patients in the olmesartan group and the 49 patients in the telmisartan treatment group who were still in the study and had their BP inadequately controlled by treatment had HCTZ 12.5 mg QD added to their treatment regimen. Both combinations induced a greater ambulatory mean (SD) systolic BP (SBP) and DBP reduction than monothera- py (SBP: 145.3 [6.1] in the olmesartan group and 140.1 [6.4] in the telmisartan group, P < 0.05; DBP: 88.1 [5.1] in the olmesartan group and 84.9 [4.9] in the telmisartan group, P < 0.05). The mean (SD) reduction from baseline in the telmisartan/HCTZ-treated patients (21.5 [10.1]/14.6 [5.2] mm Hg for 24 hours, 21.8 [10.2]/14.9 [5.2] mm Hg for daytime, and 20.4 [10.3]/13.7 [5.9] mm Hg for nighttime; all, P < 0.001 vs baseline) was significantly greater than that observed in the olmesartan/HCTZ-treated patients (18.8 [9.8]/12.3 [4.9] mm Hg for 24 hours, 19.3 [9.8]/12.8 [4.9] mm Hg for daytime, and 17.4 [10.2]/10.6 [5.5] mm Hg for nighttime; all, P < 0.001 vs baseline), with a significant difference between the 2 treatment groups (P < 0.01). Compared with mono- therapy, the add-on effect of HCTZ 12.5 mg QD administration was significantly greater in the telmisartan group than in the olmesartan group (P < 0.05); the differ- ence being more evident for nighttime BP values (SBP, P 0.031; DBP, P 0.025). Reported AEs were similar in the olmesartan/HCTZ and the telmisartan/HCTZ groups (4 patients [7%] vs 3 patients [6%]).

CONCLUSION

The addition of HCTZ 12.5 mg to telmisartan 80 mg monothera- py was associated with greater BP reduction than the addition of the same dose of HCTZ to olmesartan 20 nag monotherapy in these patients previously uncontrolled on monotherapy.

Efficacy and tolerability of olmesartan/amlodipine combination therapy in patients with mild-to-severe hypertension: focus on 24-h blood pressure control

European guidelines recommend that treating patients with hypertension to blood pressure (BP) goal is an important target for cardiovascular (CV) risk reduction. However, office BP may be a suboptimal target, given its limitations. Indeed, there is evidence that 24-h ambulatory BP monitoring (ABPM) parameters may score better in this regard, representing more accurate predictors of CV risk. In particular, mean 24-h BP and BP variability both correlate closely with hypertension end-organ damage and rate of CV events, which suggests that antihypertensive therapy should provide smooth BP control over the full 24-h dosing interval. The use of ABPM has demonstrated that fixed-dose combination therapy, comprising agents with complementary mechanisms of action, may overcome the challenge of suboptimal BP control by providing improvements in antihypertensive efficacy and tolerability throughout the 24-h period. Olmesartan/amlodipine is one of the latest combination therapies to be approved, and a number of large clinical trials have demonstrated the efficacy and tolerability of this combination in patients with mild-to-severe hypertension. Furthermore, recent ABPM studies of olmesartan/amlodipine-based treatment algorithms have shown the satisfactory 24-h antihypertensive efficacy of this fixed-dose combination. This review provides an overview of recent clinical data on the efficacy and tolerability of fixed-dose olmesartan/amlodipine combination therapy for the treatment of mild-to-severe hypertension, with a focus on sustained 24-h BP control.

Achieving BP goals with valsartan and HCTZ alone and in combination: pooled analysis of two randomized, double-blind, placebo-controlled studies

BACKGROUND

Most patients with hypertension will require combination therapy to achieve blood pressure (BP) goals, especially the elderly, obese, or those with stage 2 hypertension.

OBJECTIVE

To assess BP response and time to achieve BP goals in a diverse population of hypertensive patients treated with hydrochlorothiazide, valsartan, or a combination.

METHODS

For this secondary post-hoc analysis, data were pooled from two similar randomized, double-blind, 8-week trials that evaluated hydrochlorothiazide (12.5-25 mg) and valsartan (160 mg) monotherapies, their combination (160/12.5 mg), and placebo. Subgroups were defined by age, hypertension severity, and obesity. Adults with diastolic BP > or =95 and < or =115 mmHg were included. Goal rates were estimated from a logistic model with treatment, study, age group, race, and baseline body mass index as factors and baseline diastolic BP as a covariate. Kaplan-Meier estimates were used to calculate the time to achieve BP goals.

MAIN OUTCOME MEASURES

Efficacy variables were reductions from baseline to study end in systolic BP and diastolic BP, rates of achieving BP goals (<140/90 mmHg), and time to achieve BP goals. Adverse events were also reported for the pooled trials.

RESULTS

BP reductions at study end and goal achievement rates were greater with combination therapy (-20/15 mmHg and 72%, respectively) than with either monotherapy (valsartan 160 mg: -14/11 mmHg, 61%; hydrochlorothiazide 25 mg: -14/10 mmHg, 50%) for the overall population (N=1313) and in patient subgroups. Patients treated with initial combination therapy reached goal in 27-56% of the time needed for those treated with monotherapy. Combination therapy was well tolerated and was associated with a decreased incidence of hypokalemia compared with hydrochlorothiazide monotherapy.

CONCLUSIONS

Compared with monotherapy, combination therapy resulted in greater reductions in BP and achievement of goal BP in a shorter period of time. Although interpretation of this study is subject to the limitations associated with any post-hoc analysis, the results suggest that initiating treatment with combination therapy may be considered for expedient and effective BP control.

Pharmacotherapy Review: Angiotensin Receptor Antagonists

Angiotensin receptor blockers are one of several drug classes that act by interfering with activity of the renin-angiotensin axis. Drugs in this class are as effective as angiotensin-converting enzyme inhibitors in the reduction of blood pressure in hypertensive patients. Results from a series of outcomes trials increasingly support the use of drugs in this class as cardioprotective and renoprotective agents in patients with heart failure, diabetic nephropathy, and post-myocardial infarction.

Hydrochlorothiazide added to valsartan is more effective than when added to olmesartan in reducing blood pressure in moderately hypertensive patients inadequately controlled by monotherapy

This study was undertaken to evaluate the effects on blood pressure of hydrochlorothiazide (HCTZ) 12.5 mg added to valsartan 160 mg or to olmesartan 20 mg in hypertensive patients. After a 2-wk placebo period, 130 patients, aged 35 to 75 y, with diastolic blood pressure (DBP) >or=99 and 110 mm Hg were randomly assigned to olmesartan 20 mg once daily or to valsartan 160 mg once daily according to a prospective, parallel-arm study design. After 4 wk of monotherapy, patients whose BP was not controlled (DBP >or=90 mm Hg) were given combination treatment with HCTZ 12.5 mg for an additional 4 wk. At the end of the placebo period and at the end of each treatment period, clinical and ambulatory BP measurements were recorded. At the end of the combination therapy period, venous blood samples were drawn 2, 4, and 24 h after drug intake for evaluation of HCTZ plasma concentrations. Both combinations induced a greater ambulatory BP reduction than monotherapy. However, mean reduction from baseline in the valsartan/HCTZ-treated patients (-21.5)-14.6 mm Hg for 24 h, -21.8/-14.9 mm Hg for daytime, and -20.4/-13.7 mm Hg for nighttime systolic blood pressure [SBP]/DBP) was greater than in the olmesartan/HCTZ-treated patients )-18.8/-12.3 mm Hg for 24 h, -19.3/-12.8 mm Hg for daytime, and 17.4/-10.6 mm Hg for nighttime SBP/DBP). The difference between the effects of the 2 treatments was significant (P<.01). In particular, compared with monotherapy, the add-on effect of HCTZ 12.5 mg was significantly greater in the valsartan group than in those treated with olmesartan; the difference was more evident for nighttime BP values. Plasma concentrations of HCTZ were significantly greater with valsartan than with olmesartan at each determination time (P<.05). These findings suggest that the addition of HCTZ 12.5 mg to valsartan 160 mg monotherapy produces a greater BP reduction than the addition of the same dose of HCTZ to olmesartan 20 mg monotherapy.

The role of pulse pressure in the hemodynamic control of hypertension: exploring the link to cardiovascular remodeling

OBJECTIVE

To correlate the values in the basic blood pressure groups presented in the JNC 7th with the computed values of the Noninvasive Hemodynamic Analyzer (NHA) and to demonstrate the pathophysiological alterations by three proportional hypertensive models.

DESIGN

Hemodynamic values of each of the blood pressure groups presented in the JNC 7th are tabulated for men between 20 and 50 years of age with particular interest in Pulse Pressure.

PATIENTS

Idealized patients were used in the three groups of the proportional hypertensive models.

VALIDITY

Previous studies demonstrated that the Bias, Precision, and Accuracy of Cardiac Output measurement, compared to Thermodilution technique, resulted in statistically acceptable clinical values.

CONCLUSION

This research has successfully demonstrated, with the use of the NHA, the leading role of Pulse Pressure in normal and hypertensive patients. We are convinced that this technique can be used as an economical and time-saving alternative screening tool in clinical medicine.

The lord of the ring: mandatory role of the kidney in drug therapy of hypertension

Strong evidence supports the idea that total peripheral resistance (TPR) is increased in all forms of human and experimental hypertension. Although the etiological participation of TPR in the origin and long-term maintenance of hypertension has been extensively debated, it now seems clear that the renal, nonadaptive, infinite gain-working, pressure-sensitive natriuresis and diuresis is the main mechanism of blood pressure control in the long term. The tissue, cellular, biochemical, and genetic sensors and executors of this process have not been fully identified yet, but the role of the renal medulla has gained growing attention as the physiopathological scenario in which the key regulatory elements reside. Specifically, the functionality of the renomedullary vasculature seems to be highly responsible for blood pressure control. The vasculature of the renal medulla becomes a new and more specific target for the therapeutic intervention of hypertension. Recent data on the effect of baroreceptor-controlled renal sympathetic activity on the long-term regulation of blood pressure are integrated. The renomedullary effects of the main antihypertensive drugs are discussed, and new perspectives for the therapeutic intervention of hypertension are outlined. Comparison of the genetic program of the renal medulla before and after the development of hypertension in spontaneously hypertensive and experimentally induced animal models might provide a mechanism for identifying the key genes that become activated or suppressed in the development of high blood pressure. These genes, their encoded proteins, or other elements related to their signalling and genetic pathways might serve as new and more specific targets for the pharmacological treatment of abnormally elevated blood pressure. Besides, proteins specifically located to the luminal side of the renomedullary vascular endothelium may serve as potential targets for site-directed drug and gene therapy.