Safety and efficacy of aliskiren in the treatment of hypertension: a systematic overview

Interaction of the renin inhibitor aliskiren with the SARS-CoV-2 main protease: a molecular docking study

The renin protein is an upstream enzymatic regulator of the renin-aldosterone-angiotensin system (RAAS) essential for the maintenance of blood pressure. The angiotensin-converting enzyme-2 (ACE2) is a major component of the RAAS and a cell surface receptor exploited by the SARS-CoV-2 virus to enter host cells. A recent molecular modeling study has revealed that the direct renin peptide inhibitor remikiren can bind to the catalytic site of SARS-CoV-2 main protease (M^pro). By analogy, we postulated that the non-peptidic drug aliskiren, a more potent renin inhibitor than remikiren and a drug routinely used to treat hypertension, may also be able to interact with M^pro. An in silico comparison of the binding of the two compounds to M^pro indicates that aliskiren (ΔE = -75.9 kcal/mol) can form stable complexes with the main viral protease, binding to the active site, as remikiren (ΔE = -83.2 kcal/mol). The comparison with a panoply of 30 references compounds (mainly antiviral drugs) indicated that remikiren is a potent M^pro binder comparable to drugs like glecaprevir and pibrentasvir (ΔE = -96.5 kcal/mol). The energy of interaction (ΔE) of aliskiren with M^pro is about 10% lower than with remikiren, comparable to that calculated with drugs like velpatasvir and sofosbuvir. A model is proposed to define the drug binding site, with the best binders (including remikiren) penetrating deeply into the site, whereas the less potent binders (including aliskiren) interact more superficially with the protein.Communicated by Ramaswamy H. Sarma.

Potential Protective Role of Blood Pressure-Lowering Drugs on the Balance between Hemostasis and Fibrinolysis in Hypertensive Patients at Rest and During Exercise

In patients with hypertension, the triad represented by endothelial dysfunction, platelet hyperactivity, and altered fibrinolytic function disturbs the equilibrium between hemostasis and fibrinolysis and translates into a hypercoagulable state, which underlies the risk of thrombotic complications. This article reviews the scientific evidence regarding some biological effects of antihypertensive drugs, which can protect patients from the adverse consequences of hypertensive disease, improving endothelial function, enhancing antioxidant activity, and restoring equilibrium between hemostatic and fibrinolytic factors. These protective effects appear not to be mediated through blood pressure reduction and are not shared by all molecules of the same pharmacological class.

Angioedema Among Hypertensive Patients Treated with Aliskiren or Other Antihypertensive Medications in the United States

BACKGROUND

A non-interventional study suggested that use of angiotensin-converting enzyme inhibitors (ACEIs) or aliskiren was associated with an angioedema risk three times that of beta-blockers (BBs).

OBJECTIVE

The aim was to assess angioedema incidence rates (IRs) and the relative angioedema risk of aliskiren compared to other antihypertensive drugs (AHDs).

METHODS

A cohort study in hypertensive patients with an AHD prescription between 2007 and 2012 was conducted using data from the US PharMetrics Plus™ claims database. Angioedema was identified using the International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9CM) code 995.1. Additionally, a nested case-control analysis was conducted to assess the relative angioedema risk of aliskiren or other AHDs versus BBs.

RESULTS

A total of 3,090,114 patients were included (aliskiren n = 30,720). There were 15,744 angioedema events (IR 2.28/1000 person-years; 95% confidence interval (CI) 2.24-2.32). Aliskiren IRs were: any aliskiren 2.58 (2.08-3.17), aliskiren monotherapy 1.71 (0.74-3.37), aliskiren fixed-dose combination (FDC) 1.27 (0.41-2.96), and aliskiren free-standing combination (FSC) 2.93 (2.31-3.66). The case-control analysis included 15,100 angioedema cases and 60,400 controls; the angioedema risk for both aliskiren monotherapy and FDC was not significantly different from BBs [adjusted odds ratio (adjOR) 0.99 (95% CI 0.45-2.20) and 1.06 (0.40-2.76)]; aliskiren FSC was associated with an increased angioedema risk [adjOR 3.29 (2.42-4.48)], mainly driven by concomitant ACEI use [adjOR 7.03 (4.10-12.05)].

CONCLUSIONS

The IR and risk of angioedema in patients with aliskiren monotherapy or FDC are comparable to BBs. The higher IR and risk of angioedema identified in the aliskiren FSC group may largely be driven by the concomitant use of ACEIs.

Comparative Effects of Direct Renin Inhibitor and Angiotensin Receptor Blocker on Albuminuria in Hypertensive Patients with Type 2 Diabetes. A Randomized Controlled Trial

BACKGROUND

In patients with diabetes, albuminuria is a risk marker of end-stage renal disease and cardiovascular events. An increased renin-angiotensin system activity has been reported to play an important role in the pathological processes in these conditions. We compared the effect of aliskiren, a direct renin inhibitor (DRI), with that of angiotensin receptor blockers (ARBs) on albuminuria and urinary excretion of angiotensinogen, a marker of intrarenal renin-angiotensin system activity.

METHODS

We randomly assigned 237 type 2 diabetic patients with high-normal albuminuria (10 to <30 mg/g of albumin-to-creatinine ratio) or microalbuminuria (30 to <300 mg/g) to the DRI group or ARB group (any ARB) with a target blood pressure of <130/80 mmHg. The primary endpoint was a reduction in albuminuria.

RESULTS

Twelve patients dropped out during the observation period, and a total of 225 patients were analyzed. During the study period, the systolic and diastolic blood pressures were not different between the groups. The changes in the urinary albumin-to-creatinine ratio from baseline to the end of the treatment period in the DRI and ARB groups were similar (-5.5% and -6.7%, respectively). In contrast, a significant reduction in the urinary excretion of angiotensinogen was observed in the ARB group but not in the DRI group. In the subgroup analysis, a significant reduction in the albuminuria was observed in the ARB group but not in the DRI group among high-normal albuminuria patients.

CONCLUSION

DRI and ARB reduced albuminuria in hypertensive patients with type 2 diabetes. In addition, ARB, but not DRI, reduced albuminuria even in patients with normal albuminuria. DRI is not superior to ARB in the reduction of urinary excretion of albumin and angiotensinogen.

Blood Pressure Out of the Office: Its Time Has Finally Come

The diagnosis of hypertension includes measurement of blood pressure out of the office by either 24-hour ambulatory monitoring or home blood pressure monitoring. These methods have led to recognition of "white coat hypertension" (WCH) and "masked hypertension" (MH). Research in the 1930s first demonstrated that blood pressures in the office were often far different from those out of the office, at a time when there was no effective treatment. International attention was focused on another imminent world war and a highly controversial election in the United States. Hypertension was not a priority for concern. From the 1950s onward: (i) epidemiology linked hypertension to risk of cardiovascular disease, (ii) effective and safe drugs for treatment of hypertension appeared, (iii) randomized clinical trials demonstrated that drug treatment of hypertension is highly effective for prevention of cardiovascular disease, and (iv) advances in technology led to development of small, portable devices for recording blood pressure noninvasively at home or during usual activities. Accurate measurement of blood pressure in "real life" is now necessary and feasible for appropriate diagnosis and assessment of treatment. Out-of-office blood pressure measurement is emerging as the standard of care for hypertension.

Incidence of ischemic colitis in treated, commercially insured hypertensive adults: a cohort study of US health claims data

BACKGROUND

Ischemic colitis (IC) incidence rates (IRs) among treated hypertensive patients are poorly understood, and existing literature on the subject is sparse. Antihypertensive drugs may raise the risk of developing IC. Novel antihypertensive agents—such as the direct renin inhibitor aliskiren—have not been assessed for IC risk.

OBJECTIVES

The aims of this study were to evaluate (1) the IRs of probable IC (pIC) in treated hypertensive adults, with a focus on aliskiren-treated patients; (2) the antihypertensive therapies used; and (3) the IRs of pIC in non-hypertensive adults.

METHODS

This study selected hypertensive and non-hypertensive patients (N = 2,356,226 each) from a US health plan claims database. pIC was defined as diagnosis of IC within 3 months after colonoscopy, recto-sigmoidoscopy, or colectomy. IRs were calculated per 100,000 person-years (PYs) with 95% confidence intervals (CIs) and stratified by antihypertensive regimen.

RESULTS

IRs of pIC in hypertensive and non-hypertensive subjects were 18.6 (95% CI 17.6-19.8) and 4.0 (95% CI 3.4-4.7), respectively. The non-hypertensive cohort consisted of younger patients who may have been less prone to developing IC. The overall (i.e., all antihypertensive regimens combined) monotherapy IR per 100,000 PYs was 17.5 (95% CI 16.2-18.8), the overall dual-combination regimen IR per 100,000 PYs was 19.5 (95% CI 17.37-21.83), and the overall triple-plus combination regimen IR per 100,000 PYs was 27.7 (95% CI 22.72-33.38).

CONCLUSION

Study results indicate that the treated hypertensive patients may have a higher risk of pIC compared with non-hypertensive populations. The quantity of antihypertensive agents prescribed may contribute to IC more than treatment duration.

Aliskiren limits abdominal aortic aneurysm, ventricular hypertrophy and atherosclerosis in an apolipoprotein-E-deficient mouse model

In the present study, the efficacy of aliskiren in limiting the progression of abdominal aortic aneurysm, ventricular hypertrophy and atherosclerosis were examined in a mouse model. Aliskiren limited the progression of these pathologies, suggesting the potential of this medication for cardiovascular-protective protection.

The role of direct renin inhibitors in the treatment of the hypertensive diabetic patient

Hypertensive patients with diabetes exhibit an increased risk for cardiovascular complications, such as acute coronary syndrome, stroke, heart failure and chronic kidney disease (CKD). These two chronic diseases are linked to a high rate of morbidity and mortality and for this reason it is important for the clinician to recognize the need for effective treatment of hypertension, which can require combination therapy to achieve blood pressure (BP) goals. Direct renin inhibitors (DRIs) may be useful in combination with angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin II receptor blockers (ARBs) as they provide a more complete blockade of the renin-angiotensin-aldosterone system (RAAS), effectively suppressing residual angiotensin II production and the counter-regulatory increase in plasma renin activity observed in patients receiving monotherapy with ACEIs or ARBs. Some questions regarding the action of aliskiren in cardiovascular and renal disorders are open. In particular, the combination therapy of aliskiren and a RAAS blocker in diabetic hypertensive patients with CKD is controversial. Several published studies demonstrated that aliskiren is suitable for once-daily administration and its antihypertensive effect is comparable or superior to that of other antihypertensive agents at recommended doses, with a good tolerability profile. At the moment the association with ACEIs and ARBs is not recommended in patients with type 2 diabetes mellitus (T2DM) and renal impairment even if a recent published open-label study of low-dose aliskiren (150 mg/daily) in association with ACEIs or ARBs has demonstrated a good tolerability profile without the adverse events found in other studies. This review provides a brief overview of RAAS blocking, in particular the rationale and clinical evidence supporting the use of the DRI aliskiren, in high-risk patients with T2DM.

The safety and short-term efficacy of aliskiren in the treatment of immunoglobulin a nephropathy--a randomized cross-over study

Background

Laboratory research and previous study suggest that aliskiren, a direct renin inhibitor, has anti-proteinuric effects. We conducted a randomized crossover study to evaluate the anti-proteinuric effect of aliskiren in patients with immunoglobulin A (IgA) nephropathy.

Methods

We studied 22 patients with biopsy-proven IgA nephropathy and persistent proteinuria despite angiotensin converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB). Patients were randomized to either oral aliskiren 300 mg/day or placebo for 16 weeks and then crossed over to the other treatment arm after a washout period. Proteinuria, estimated glomerular filtration rate (eGFR), blood pressure, and serum potassium were monitored.

Results

After aliskiren treatment, there was a significant reduction in proteinuria in 4 weeks (1.76±0.95 to 1.03±0.69 g:g-Cr, p<0.0001), which remained at a low level throughout the treatment period. There was a significant difference in proteinuria between the aliskiren and placebo groups from 4 to 16 weeks after treatment (p<0.01 for all comparisons). After aliskiren treatment, there were modest but statistically significant reductions in eGFR (57.2±29.1 to 54.8±29.3 ml/min/1.73 m², p = 0.013) and diastolic blood pressure (72.6±12.3 to 66.2±11.2 mmHg, p<0.0001). None of the patient developed severe hyperkalemia (serum potassium ≥6.0 mmol/l) during the study period.

Conclusions

Aliskiren has anti-proteinuric effect in patients with IgA nephropathy and persistent proteinuria despite ACE inhibitor or ARB. Further studies are needed to confirm the renal protecting effect of direct renin inhibition in chronic proteinuric kidney diseases.

Trial Registration

ClinicalTrials.gov NCT00870493

Renin-Angiotensin system and sympathetic neurotransmitter release in the central nervous system of hypertension

Many Studies suggest that changes in sympathetic nerve activity in the central nervous system might have a crucial role in blood pressure control. The present paper discusses evidence in support of the concept that the brain renin-angiotensin system (RAS) might be linked to sympathetic nerve activity in hypertension. The amount of neurotransmitter release from sympathetic nerve endings can be regulated by presynaptic receptors located on nerve terminals. It has been proposed that alterations in sympathetic nervous activity in the central nervous system of hypertension might be partially due to abnormalities in presynaptic modulation of neurotransmitter release. Recent evidence indicates that all components of the RAS have been identified in the brain. It has been proposed that the brain RAS may actively participate in the modulation of neurotransmitter release and influence the central sympathetic outflow to the periphery. This paper summarizes the results of studies to evaluate the possible relationship between the brain RAS and sympathetic neurotransmitter release in the central nervous system of hypertension.