Comprehensive overview: efficacy, tolerability, and cost-effectiveness of irbesartan

Cost-effectiveness of ace inhibitors versus ARBs in heart failure management

BACKGROUND

Heart failure is a chronic condition that imposes a significant burden on healthcare systems worldwide. Effective management is crucial for improving patient outcomes and reducing costs. Angiotensin-converting enzyme (ACE) inhibitors and angiotensin II receptor blockers (ARBs) are widely used to manage heart failure by reducing cardiac strain and preventing disease progression. Despite their common use, ACE inhibitors and ARBs differ in mechanisms, cost, and potential side effects. ACE inhibitors have long been the standard treatment, while ARBs are often prescribed to patients intolerant to ACE inhibitors, particularly due to side effects like cough. Given these differences, evaluating the cost-effectiveness of these treatments is essential. This study compares the cost-effectiveness of ACE inhibitors and ARBs from a healthcare system perspective, considering both direct medical costs and health outcomes.

METHODS

A cost-effectiveness analysis was conducted using a decision-analytic Markov model to simulate heart failure progression in a hypothetical cohort. Data inputs included clinical trial outcomes, real-world effectiveness data, direct medical costs (medications, hospitalizations, monitoring), and utility values for quality of life. The primary outcome measures were the cost per quality-adjusted life year gained and the incremental cost-effectiveness ratio. Sensitivity analyses tested the robustness of results, and subgroup analyses were conducted based on age and disease severity.

RESULTS

The base-case analysis showed that ACE inhibitors were associated with lower overall costs and slightly higher quality-adjusted life years than ARBs. Sensitivity analyses revealed that variations in key parameters, such as transition probabilities, mortality rates, and healthcare expenses, had limited impact on the overall cost-effectiveness conclusions. Subgroup analyses indicated that ACE inhibitors and ARBs exhibited similar cost-effectiveness profiles for patients aged <65 and ≥65 years. However, among patients with severe heart failure, ARBs demonstrated a higher incremental cost-effectiveness ratio compared with ACE inhibitors, suggesting reduced cost-effectiveness in this subgroup.

CONCLUSION

ACE inhibitors are likely a more cost-effective option for managing heart failure than ARBs, particularly from a healthcare system perspective. The findings underscore the importance of tailoring treatment decisions to individual patient factors, preferences, and clinical conditions, providing valuable insights for healthcare policy and practice, particularly regarding cost-effectiveness across patient subgroups.

Virtual drug screen reveals context-dependent inhibition of cardiomyocyte hypertrophy

BACKGROUND AND PURPOSE

Pathological cardiomyocyte hypertrophy is a response to cardiac stress that typically leads to heart failure. Despite being a primary contributor to pathological cardiac remodelling, the therapeutic space that targets hypertrophy is limited. Here, we apply a network model to virtually screen for FDA-approved drugs that induce or suppress cardiomyocyte hypertrophy.

EXPERIMENTAL APPROACH

A logic-based differential equation model of cardiomyocyte signalling was used to predict drugs that modulate hypertrophy. These predictions were validated against curated experiments from the prior literature. The actions of midostaurin were validated in new experiments using TGFβ- and noradrenaline (NE)-induced hypertrophy in neonatal rat cardiomyocytes.

KEY RESULTS

Model predictions were validated in 60 out of 70 independent experiments from the literature and identify 38 inhibitors of hypertrophy. We additionally predict that the efficacy of drugs that inhibit cardiomyocyte hypertrophy is often context dependent. We predicted that midostaurin inhibits cardiomyocyte hypertrophy induced by TGFβ, but not noradrenaline, exhibiting context dependence. We further validated this prediction by cellular experiments. Network analysis predicted critical roles for the PI3K and RAS pathways in the activity of celecoxib and midostaurin, respectively. We further investigated the polypharmacology and combinatorial pharmacology of drugs. Brigatinib and irbesartan in combination were predicted to synergistically inhibit cardiomyocyte hypertrophy.

CONCLUSION AND IMPLICATIONS

This study provides a well-validated platform for investigating the efficacy of drugs on cardiomyocyte hypertrophy and identifies midostaurin for consideration as an antihypertrophic drug.

Cost Effectiveness of ACEIs/ARBs versus Amlodipine Monotherapies: A Single-Center Retrospective Chart Review

The aim of this retrospective chart review study was to examine the cost effectiveness of angiotensin-converting enzyme inhibitors (ACEIs); angiotensin receptor blockers (ARBs); and dihydropyridine calcium channel blockers (CCBs) such as amlodipine, monotherapies in the management of essential hypertension among adult patients (≥18 years) without cancer, cardiovascular disease, and chronic kidney disease in the primary care clinics of a university-affiliated tertiary care hospital. Patients were followed up for at least 12 months from the initiation of therapy. Propensity score bin bootstrapping with 10,000 replications was conducted to generate the 95% confidence intervals (CI) for both treatment outcome (e.g., reduction of the systolic (SBP) and diastolic blood pressures (DBP) in mmHG) and the cost (e.g., costs of drugs, clinic visits, and labs in Saudi riyals (SAR)). Among the 153 included patients who met the inclusion criteria, 111 patients were on ACEIs/ARBs, while 44 patients were on amlodipine. On the basis of the bootstrap distribution, we found that the use of ACEIs/ARBs was associated with an incremental reduction of SBP of up to 4.46 mmHg but with an incremental cost of up to SAR 116.39 (USD 31.04), which results in an incremental cost effectiveness ratio (ICER) of SAR 26.09 (USD 6.95) per 1 mmHg reduction with 55.26% level of confidence. With regard to DBP, ACEIs/ARBs were associated with an incremental reduction of DBP of up to 5.35 mmHg and an incremental cost of up to SAR 144.96 (USD 38.66), which results in an ICER of SAR 27.09 (USD 7.23) per 1 mmHg reduction with 68.10% level of confidence. However, ACEIs/ARBs were less effective and costlier than amlodipine in reducing SBP and DBP with 44.74% and 31.89% levels of confidence, respectively. The findings of this study indicate that the use of ACEI or ARB as a monotherapy seems to be more effective than amlodipine monotherapy in the management of essential hypertension in primary care settings with minimal incremental cost.

Irbesartan in Marfan syndrome (AIMS): a double-blind, placebo-controlled randomised trial

BACKGROUND

Irbesartan, a long acting selective angiotensin-1 receptor inhibitor, in Marfan syndrome might reduce aortic dilatation, which is associated with dissection and rupture. We aimed to determine the effects of irbesartan on the rate of aortic dilatation in children and adults with Marfan syndrome.

METHODS

We did a placebo-controlled, double-blind randomised trial at 22 centres in the UK. Individuals aged 6-40 years with clinically confirmed Marfan syndrome were eligible for inclusion. Study participants were all given 75 mg open label irbesartan once daily, then randomly assigned to 150 mg of irbesartan (increased to 300 mg as tolerated) or matching placebo. Aortic diameter was measured by echocardiography at baseline and then annually. All images were analysed by a core laboratory blinded to treatment allocation. The primary endpoint was the rate of aortic root dilatation. This trial is registered with ISRCTN, number ISRCTN90011794.

FINDINGS

Between March 14, 2012, and May 1, 2015, 192 participants were recruited and randomly assigned to irbesartan (n=104) or placebo (n=88), and all were followed for up to 5 years. Median age at recruitment was 18 years (IQR 12-28), 99 (52%) were female, mean blood pressure was 110/65 mm Hg (SDs 16 and 12), and 108 (56%) were taking β blockers. Mean baseline aortic root diameter was 34·4 mm in the irbesartan group (SD 5·8) and placebo group (5·5). The mean rate of aortic root dilatation was 0·53 mm per year (95% CI 0·39 to 0·67) in the irbesartan group compared with 0·74 mm per year (0·60 to 0·89) in the placebo group, with a difference in means of -0·22 mm per year (-0·41 to -0·02, p=0·030). The rate of change in aortic Z score was also reduced by irbesartan (difference in means -0·10 per year, 95% CI -0·19 to -0·01, p=0·035). Irbesartan was well tolerated with no observed differences in rates of serious adverse events.

INTERPRETATION

Irbesartan is associated with a reduction in the rate of aortic dilatation in children and young adults with Marfan syndrome and could reduce the incidence of aortic complications.

FUNDING

British Heart Foundation, the UK Marfan Trust, the UK Marfan Association.

A gender-specific association of the polymorphism Ile197Met in the kininogen 1 gene with plasma irbesartan concentrations in Chinese patients with essential hypertension

This study was conducted to explore interactions in the association of the kininogen (KNG1) Ile197Met polymorphism and gender with plasma concentrations of irbesartan in Chinese patients with essential hypertension. A total of 1100 subjects with essential hypertension received a daily oral dose of 150 mg irbesartan for twenty-eight consecutive days. High-performance liquid chromatography-fluorescence (HPLC) was used to detect plasma irbesartan concentrations on day 28. The KNG1 Ile197Met gene polymorphism was determined using high-throughput TaqMan technology. The frequency distribution of KNG1 Ile197Met genotype conformed to the Hardy-Weinberg equilibrium. After 28 days of treatment, patients with the GG genotype had significantly lower irbesartan concentrations (P = 0.033) compared to homozygous TT genotype carriers. After stratifying by gender, male G allele carriers had significantly lower irbesartan concentrations (GG, P = 0.015; TG, P = 0.015, respectively) relative to TT genotype after adjusting for age, region, body mass index (BMI), smoking, and alcohol consumption. However, there was no significant difference in female subjects. A further test for a multiplicative interaction between the KNG1 Ile197Met polymorphism and gender in association with ln-plasma irbesartan concentrations in a multiple linear regression model was also significant (P for interaction = 0.033). This is the first study to suggest that gender may influence the association of the Ile197Met variant of KNG1 with ln-plasma irbesartan concentration. This finding may indicate that the interaction of gender and the KNG1 Ile197Met gene polymorphism can influence plasma trough irbesartan concentrations, which may contribute to a better development of personalized hypertensive treatment in Chinese patients.

Cost-effectiveness Analyses of Antihypertensive Medicines: A Systematic Review

CONTEXT

Hypertension affects one third of the U.S. adult population. Although cost-effectiveness analyses of antihypertensive medicines have been published, a comprehensive systematic review across medicine classes is not available.

EVIDENCE ACQUISITION

PubMed, Embase, Cochrane Library, and Health Technology Assessment were searched to identify original cost-effectiveness analyses published from 1990 through August 2016. Results were summarized by medicine class: angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), calcium channel blockers (CCBs), thiazide-type diuretics, β-blockers, and others. Incremental cost-effectiveness ratios (ICERs) were adjusted to 2015 U.S. dollars.

EVIDENCE SYNTHESIS

Among 76 studies reviewed, 14 compared medicines with no treatment, 16 compared medicines with conventional therapy, 29 compared between medicine classes, 13 compared within medicine class, and 11 compared combination therapies. All antihypertensives were cost effective compared with no treatment (ICER/quality-adjusted life year [QALY]=dominant-$19,945). ARBs were more cost effective than CCBs (ICER/QALY=dominant-$13,016) in nine comparisons, whereas CCBs were more cost effective than ARBs (ICER/QALY=dominant) in two comparisons. ARBs were more cost effective than ACEIs (ICER/QALY=dominant-$34,244) and β-blockers (ICER/QALY=$1,498-$18,137) in all eight comparisons.

CONCLUSIONS

All antihypertensives were cost effective compared with no treatment. ARBs appeared to be more cost effective than CCBs, ACEIs, and β-blockers. However, these latter findings should be interpreted with caution because these findings are not robust due to the substantial variability across the studies, including study settings and analytic models, changes in the cost of generic medicines, and publication bias.