Do valsartan and losartan have the same effects in the treatment of coronary artery disease?

Immunomodulation and immunopharmacology in heart failure

The immune system is intimately involved in the pathophysiology of heart failure. However, it is currently underused as a therapeutic target in the clinical setting. Moreover, the development of novel immunomodulatory therapies and their investigation for the treatment of patients with heart failure are hampered by the fact that currently used, evidence-based treatments for heart failure exert multiple immunomodulatory effects. In this Review, we discuss current knowledge on how evidence-based treatments for heart failure affect the immune system in addition to their primary mechanism of action, both to inform practising physicians about these pleiotropic actions and to create a framework for the development and application of future immunomodulatory therapies. We also delineate which subpopulations of patients with heart failure might benefit from immunomodulatory treatments. Furthermore, we summarize completed and ongoing clinical trials that assess immunomodulatory treatments in heart failure and present several therapeutic targets that could be investigated in the future. Lastly, we provide future directions to leverage the immunomodulatory potential of existing treatments and to foster the investigation of novel immunomodulatory therapeutics.

The adenosine A2A receptor antagonist/inverse agonist, KW-6356 enhances the anti-parkinsonian activity of L-DOPA with a low risk of dyskinesia in MPTP-treated common marmosets

The adenosine A_2A receptor antagonist/inverse agonist, KW-6356 has been shown to be effective in Parkinson's disease (PD) patients as monotherapy and as an adjunct therapy to L-3,4-dihydroxyphenylalanine (L-DOPA)/decarboxylase inhibitor. However, the effects of KW-6356 combined with L-DOPA on anti-parkinsonian activity and established dyskinesia has not been investigated in preclinical experiments. We examined the effects of combination of KW-6356 with L-DOPA in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-treated common marmosets. Oral administration of KW-6356 (1 mg/kg) enhanced the anti-parkinsonian activities of various doses of L-DOPA (2.5-10 mg/kg). In MPTP-treated common marmosets primed with L-DOPA to show dyskinesia, KW-6356 (1 mg/kg) also enhanced the anti-parkinsonian activities of various doses of L-DOPA (1.25-10 mg/kg) but not dyskinesia. Chronic co-administration of KW-6356 (1 mg/kg) with a low dose of L-DOPA (2.5 mg/kg) for 21 days increased the degree of dyskinesia induced by the low dose of L-DOPA, but the amplitude of dyskinesia induced by combined administration of KW-6356 (1 mg/kg) with L-DOPA (2.5 mg/kg) was lower than that induced by an optimal dose of L-DOPA (10 mg/kg). These results suggest that KW-6356 can be used to potentiate the effects of a wide range of L-DOPA doses with a low risk of dyskinesia for the treatment of PD.

The short-term effects of angiotensin II receptor blockers on albuminuria and renal function in Korean patients

Each angiotensin II receptor blocker (ARB) asserts independent molecular effects. No study has compared the renoprotective potency of different types of ARBs in Korea. This study evaluated the differences among medications for treating albuminuria. Data were obtained from electronic medical records of adult patients who underwent albuminuria test and received treatment with either angiotensin-converting enzyme inhibitors (ACEIs) or ARBs between January 2009 and June 2016. Patients' albuminuria and renal function data were observed for three months after treatment initiation. In total, 1475 patients were included. Patients treated with ACEIs had no significant changes in albuminuria (from 127.7 ± 55.1 mg/g to 46.7 ± 18.7 mg/g, P = .127), but those treated with ARBs showed significant improvement (from 491.2 ± 33.2 mg/g to 372.0 ± 28.0 mg/g, P < .001). The ARB group had significantly more patients with normal albuminuria after treatment (from 55.8% to 59.3% for normal albuminuria, from 16.7% to 18.5% for moderately increased albuminuria and from 27.5% to 22.2% for severely increased albuminuria, P = .005), but renal function did not change significantly. Subgroup analysis of ARB types showed that candesartan (from 712.5 ± 71.1 to 489.8 ± 57.8 mg/g, P < .001) and irbesartan (from 522.6 ± 65.7 to 352.6 ± 54.3 mg/g, P < .001) had significant effects. Candesartan improved albuminuria in patients older than 60 years (from 506.9 ± 84.2 to 371.9 ± 70.6 mg/g, P = .004) and irbesartan improved albuminuria in patients with glomerular filtration rate <60 (from 551.6 ± 100.0 to 392.4 ± 76.2, P = .007). Only irbesartan and candesartan could reduce albuminuria, suggesting that all ARBs do not have the same outcome. This indicates the importance of optimizing ARB selection, considering both patient condition and organ-specific characteristics of medications.

Depressor and Anti-Inflammatory Effects of Angiotensin II Receptor Blockers in Metabolic and/or Hypertensive Patients With Coronary Artery Disease: A Randomized, Prospective Study (DIAMOND Study)

Background

We compared the efficacy and safety of azilsartan to those of olmesartan in a prospective, randomized clinical trial.

Methods

Forty-four hypertensive patients who had coronary artery disease (CAD) were enrolled. We randomly assigned patients to changeover from their prior angiotensin II receptor blockers (ARBs) to either azilsartan or olmesartan, and followed the patients for 12 weeks.

Results

Office systolic blood pressure (SBP) in the azilsartan group was significantly decreased after 12 weeks. SBP and diastolic blood pressure (DBP) after 12 weeks in the azilsartan group were significantly lower than those in the olmesartan group. The percentage of patients who reached the target BP at 12 weeks (78%) in the azilsartan group was significantly higher than that at 12 weeks (45%) in the olmesartan group. There were no significant changes in pentraxin-3, high-sensitively C-reactive protein or adiponectin in blood after 12 weeks in either group. Although serum levels of creatinine (Cr) in the azilsartan group significantly increased, these changes were within the respective normal range.

Conclusion

In conclusion, the ability of azilsartan to reduce BP may be superior to that of prior ARBs with equivalent safety in hypertensive patients with CAD.

Comparison of the efficacies of irbesartan and olmesartan after successful coronary stent implantation

OBJECTIVE

We compared the efficacies of irbesartan and olmesartan after successful stent implantation in patients with stable angina.

METHODS

Twenty-six patients were randomly divided into irbesartan and olmesartan groups and treated for approximately eight months (at follow-up coronary angiography).

RESULTS

There were no differences in blood pressure (BP) reduction or late loss between the groups. The BP levels in both groups at follow-up were significantly reduced. The equality of variance of systolic (S)BP (i.e., the intragroup standard deviation of SBP) in the irbesartan group was significantly smaller than that observed in the olmesartan group at follow-up. In addition, log[pentraxin-3] was significantly decreased in all of the patients at follow-up, with no differences between the groups. Interestingly, the levels of log[high-sensitive C-reactive protein (hs-CRP)] measured at 0 weeks were positively associated with in-stent late loss, and among independent biochemical variables in addition to age, gender, body mass index and the kind of angiotensin receptor blockers at 0 weeks, only these levels were related to in-stent late loss, as assessed by a multivariate analysis.

CONCLUSION

The ability of irbesartan to reduce BP is comparable to that of olmesartan, and irbesartan exhibits a lower variance of systolic BP after treatment. The level of log[hs-CRP] before stent implantation is a predictor of in-stent late loss.

Comparison of efficacy of low- (80 mg/day) and high- (160-320 mg/day) dose valsartan in the prevention of in-stent restenosis after implantation of bare-metal stents in type B2/C coronary artery lesions

BACKGROUND AND OBJECTIVE

Results from the VALVACE (VALsartan Versus ACE inhibition after bare metal stent implantation) trial suggest that prevention of in-stent restenosis after implantation of bare-metal stents in type B2/C coronary artery lesions is possible after administration of valsartan 80 mg/day. However, the restenosis rate in patients with stable angina was relatively high (27%) with this dosage and no different from patients taking ACE inhibitors. Therefore, a 1 : 1 matched comparison on a case-control basis was initiated in a prospective controlled registry using a higher dose of valsartan, 160-320 mg/day.

METHODS

A total of 450 patients (241 men, mean age 62.7 +/- 9.1 years) with matched demographic and angiographic characteristics to patients in the VALVACE trial were treated with high-dose oral valsartan 160-320 mg/day over 6 months until control angiography. Angiographic restenosis rate, target lesion revascularization (TLR) and target vessel revascularization (TVR) rates, major adverse cardiac event (MACE) rate (death, myocardial infarction, and stent thrombosis) and mean late lumen loss were analysed after 6 months. Results were compared with the results of the VALVACE trial. Analysis of the combined results of the current study together with the VALVACE trial data enabled calculation of the gender- and dose-dependent effects of valsartan.

RESULTS

In the high-dose valsartan group, the angiographic restenosis rate in 368 patients with control angiography was 7.3% compared with 19.5% in the low-dose group (VALVACE) [p < 0.0001]. Mean late lumen loss was 0.37 +/- 0.3 mm in the high-dose group compared with 0.53 +/- 0.31 mm in the VALVACE trial (p < 0.01). TLR and TVR rates were 4.3% in the high-dose group compared with 9% in the VALVACE trial (p < 0.01). The MACE rate was 0% in the high-dose group compared with 1.5% in the VALVACE trial (p < 0.01). Summarizing the data for valsartan, the in-stent restenosis rates in men were 22.7%, 13.3%, 6.7%, and 5.4% in patients receiving 80, 160, 240, and 320 mg/day, respectively. In women, the in-stent restenosis rates were 13.3% and 6.3% in patients receiving 80 and 160 mg/day, respectively; no restenosis occurred in patients receiving higher doses.

CONCLUSION

Administration of high-dose oral valsartan 160-320 mg/day after implantation of bare-metal stent in type B2/C coronary artery lesions reduces angiographic in-stent restenosis, TLR, TVR, late lumen loss, and MACE rates more effectively than low-dose valsartan 80 mg/day.

Comparison of the efficacy and safety of irbesartan and olmesartan in patients with hypertension (EARTH study)

Fifty-four patients were randomly divided into irbesartan and olmesartan groups. Blood pressure (BP) was significantly decreased in all patients at 12 weeks. In particular, BP in patients who initially received irbesartan showed significant reductions. The equality of variance of BP in the irbesartan group was significantly smaller than that in the olmesartan group at 12 weeks. Blood concentrations of adiponectin were significantly increased in the irbesartan group at 12 weeks. Log [pentraxin-3] in the irbesartan group were significantly decreased. In conclusion, the ability of irbesartan to reduce BP is comparable to that of olmesartan with equivalent safety.

Neointimal hyperplasia inhibition effect of angiotensin II type 1 receptor blockers in patients after coronary stent implantation: a meta-analysis

BACKGROUND AND OBJECTIVE

It remains unclear whether angiotensin II type 1 receptor antagonists (angiotensin receptor blockers [ARBs]) can inhibit neointimal hyperplasia after stent implantation in patients with coronary artery disease. The aim of this meta-analysis was therefore to evaluate the benefits of ARBs in patients after coronary stent implantation based on the currently available randomized controlled trials.

METHODS

We conducted a pooled analysis of randomized controlled trials to compare outcomes after stent implantation in patients administered ARBs with those not administered ARBs. We searched Ovid/MEDLINE, EMBASE, and the ISI web of knowledge using the terms 'angiotensin receptor blocker,' 'renin angiotensin system inhibitor,' 'angiotensin receptor antagonist,' 'stent,' 'angiograph,' 'percutaneous coronary intervention (PCI),' and 'coronary artery disease.' Published meta-analyses, review articles, and editorials were reviewed for potential studies of interest. The inclusion criteria were randomized controlled trials published in English, with a follow-up period of 6 months, comparing the outcomes after coronary stent implantation with and without the administration of any kind of ARB, reporting at least one outcome of interest (restenosis rate and late lumen loss). Data abstraction included study design, patient characteristics, follow-up period, type of ARB, type of stent, restenosis rate, and late lumen loss. Fixed-effects models were used to calculate the pooled relative risk for the restenosis rate and the standardized mean difference for late lumen loss.

RESULTS

Five studies were included, with a total number of 624 patients. Seventy-five of 314 patients in the ARB group were diagnosed with in-stent restenosis at the 6-month follow-up, compared with 87 of 310 patients in the control group (relative risk 0.85; 95% CI 0.65, 1.11; p = 0.23). Consistent with this, there was no significant difference in late lumen loss between the two groups (0.04 mm; 95% CI -0.15, 0.23; p = 0.66).

CONCLUSION

There is no evident benefit with the use of an ARB in terms of inhibition of neointimal hyperplasia in patients after coronary stent implantation.

Review: angiotensin II type 1 receptor blockers: class effects versus molecular effects

Highly selective angiotensin II (Ang II) type 1 (AT(1)) receptor blockers (ARBs) are now available. The AT(1) receptor is a member of the G protein-coupled receptor (GPCR) superfamily and block the diverse effects of Ang II. Several ARBs are available for clinical use. Most ARBs have common molecular structures (biphenyl-tetrazol and imidazole groups) and it is clear that ARBs have 'class effects'. On the other hand, recent clinical studies have demonstrated that not all ARBs have the same effects, and some benefits conferred by ARBs may not be class effects, and instead may be 'molecular effects'. In addition, each ARB has been clearly shown to have specific molecular effects in basic experimental studies, and these effects may be due to small differences in the molecular structure of each ARB. However, it is controversial whether ARBs have molecular effects in a clinical setting. Although the presence of molecular effects for each ARB based on experimental studies may not directly influence the clinical outcome, this possibility has not been adequately evaluated. This review focuses on the class effects versus molecular effects of ARBs from bench to bedside.

First-in-man use of polymer-free valsartan-eluting stents in small coronary vessels: a comparison to polymer-free rapamycin (2%)-eluting stents

Introduction. Orally administered angiotensin receptor antagonists administered after bare-metal stent implantation and even after drug-eluting stent implantation seem to lower in-stent restenosis rates.Whether valsartan-eluting stents are similarly effective was tested here in a first-in-man trial.

Materials and methods. The efficacy of a polymer-free drug-eluting stent coated with 300 mcg valsartan was compared to a coating with a 2% rapamycin solution in small (≤ 2.5 mm) coronary vessels with and without oral valsartan on the basis of the YUKON Choice stent system (Translumina GmbH, Hechingen, Germany). Fifteen patients (eight males, mean age 64.4±7.7 years) were treated with YUKON Choice valsartan-eluting stents and 30 patients (24 males, mean age 65.7±8.4 years) received YUKON Choice rapamycin-eluting stents. Clopidogrel was given for six months in all patients.

Results. Within the first 30 days, no adverse events occurred in either group. Binary in-stent restenosis rate was 30.8% (four in 13 angiographic controls) in the valsartan-eluting stent group and 35.0% (eight in 20 angiographic controls) in the rapamycin-eluting YUKON Choice stent group. Mean late lumen loss was 0.78±0.53 mm and 0.79±0.58 mm, respectively. Target lesion and target vessel revascularisation rate was 26.6% and 25.0%, respectively. No restenoses in rapamycin-eluting YUKON Choice stents appeared in 12 patients with adjunct oral valsartan administration.

Conclusions. If polymer-free YUKON Choice stents are used in small vessels, valsartan-eluting stents show an identical efficacy as rapamycin-loaded stents. In patients with rapamycin-eluting YUKON Choice stents it seems that the efficacy can be increased by oral valsartan administration.

Which strategy is more effective for the treatment of cardiovascular disease: high-dose angiotensin II type 1 receptor antagonist monotherapy or combination therapy?

Angiotensin II type 1 (AT(1)) receptor antagonists (blockers) [ARBs] are highly selective for the AT(1) receptor and block the diverse effects of angiotensin II. When high BP is not controlled by low-dose ARB monotherapy, physicians need to employ another strategy, either high-dose ARB monotherapy or combination therapy with calcium channel antagonists (blockers) [CCBs], diuretics, or other agents. High-dose ARB monotherapy is more effective for decreasing proteinuria than low-dose ARB monotherapy or CCBs. Although the ARB valsartan has been shown to prevent coronary restenosis in a clinical study (Val-PREST [Valsartan for prevention of restenosis after stenting of type B2/C lesions]), it is still unclear whether ARBs help to prevent restenosis. The results reported by Peters in this issue highlight the relative efficacies of low- (80 mg/day) and high-dose valsartan (160-320 mg/day) for the prevention of in-stent restenosis after the implantation of bare-metal stents, and suggest that high-dose valsartan can reduce the in-stent restenosis rate, target lesion revascularization and target vessel revascularization rates, late lumen loss, and major adverse cardiac events rate more effectively than low-dose valsartan. A better understanding of the differences in the efficacies of high- and low-dose ARBs could be useful in the treatment of patients with cardiovascular disease and may resolve the issue of whether ARBs prevent coronary restenosis. Clinical benefits may be induced by complete blockade of the renin-angiotensin system using high-dose ARB monotherapy. Therefore, physicians need to select a strategy carefully; i.e. either high-dose ARB monotherapy or combination therapy.

Do all angiotensin II type 1 receptor blockers have the same beneficial effects?

Angiotensin II type 1 (AT(1)) receptor blockers (ARBs) are highly selective for the AT(1) receptor, which is a member of the G protein-coupled receptor superfamily (GPCRs), and block the diverse effects (hypertension, hypertrophy, heart failure, proteinuria etc.) of angiotensin II. Many ARBs are in clinical use and have been shown to be safe and effective. Over the past several years, reports have discussed the different degrees of the beneficial effects of ARBs. As ARBs do not all have the same effects, the benefits conferred by ARBs may not be class effects. These different effects may be due to differences in the molecular characteristics of ARBs. The results reported by Le et al. in this issue highlight the different characteristics of two ARBs, olmesartan and telmisartan, and suggest that the higher degree of insurmountability, slower dissociation, and higher affinity of olmesartan compared to telmisartan for AT(1) receptors may help it to form a tight binding complex with this receptor. A better understanding of the different molecular mechanisms for each ARB could be useful for the treatment of patients.