Differential pharmacology and benefit/risk of azilsartan compared to other sartans

Azilsartan as a preventive agent against cyclophosphamide-induced testicular injury in male rats

Cyclophosphamide (CP) is a popular cancer treatment; however, despite its efficacy, it is known to cause harm to the testicles. To mitigate the reproductive damage caused by CP in male rats, we examined the protective effect of azilsartan (AZ) on CP-induced testicular damage. Thirty Sprague-Dawley male rats were equally divided into three groups: normal control group: received 0.5% CMC suspension for 13 days; induction group: received a single dose of 200 mg/kg of CP on day 6 by intraperitoneal (IP) injection, azilsartan group: received azilsartan (4 mg/kg) orally for 5 days followed by a single dose of 200 mg/kg of (CP) on day 6 by IP injection, then azilsartan administered again for 7 days. Animals were sacrificed on day 14, and sperm characteristics, testosterone levels, and testicular histopathology were evaluated. Induction with CP caused a significant reduction in median value compared to normal control in sperm count (12.0 vs. 22.0 × 106/mm3), sperm motility (30 vs. 90%), abnormal sperm (30.32 vs. 14.43%), dead sperm count (32.43 vs. 10.49 × 106/mm3), DNA fragmentation (21.57 vs. 5.49%); meanwhile, azilsartan prevent these effects on median sperm count (17.0 × 106/mm3), sperm motility (70.0%), abnormal sperm (23.19%), dead sperm count (26.17 × 106/mm3), DNA fragmentation (13.81%), and improved plasmatic testosterone levels compared to the CP group and prevented histopathological alterations of the testes. Azilsartan's mitigation of CP's effects suggests it can prevent male rats' reproductive damage caused by CP. One possible explanation for AZ's protective effects is that it inhibits lipid peroxidation and has antioxidant properties.

Severe refractory hypotension during induction of general anesthesia in patient after 48 hours of azilsartan discontinuation: A case report

RATIONALE

Angiotensin II receptor blockers (ARBs) are currently considered first-line antihypertensive drugs, effectively inhibiting the renin-angiotensin-aldosterone system. However, ARBs have been associated with intraoperative hypotension during general anesthesia. Although it is recommended to discontinue ARBs for 24 hours before surgery, the optimal duration of discontinuation remains unclear. We present a severe refractory hypotension encountered during general anesthesia despite discontinuing ARBs for 48 hours before anesthesia.

PATIENT CONCERNS

A severe refractory hypotension occurred during the induction of general anesthesia for cranioplasty in a 66-year-old male patient (170 cm/75 kg). The patient was taking azilsartan, angiotensin receptor blocker, for hypertension, which was discontinued 48 hours before anesthesia induction. Despite repeated administration of ephedrine and continuous infusion of norepinephrine, hemodynamic instability did not improve. Therefore, the surgery was postponed.

DIAGNOSIS

The patient was diagnosed with angiotensin receptor blocker-induced refractory hypotension.

INTERVENTIONS

Before the second surgery, the angiotensin receptor blocker was discontinued 96 hours prior to the surgery. Invasive blood pressure monitoring was performed before anesthesia induction, and vasopressin was prepared. General anesthesia was induced using remimazolam and maintained with desflurane.

OUTCOMES

The surgery was completed successfully without occurrence of refractory hypotension.

LESSONS

Refractory hypotension induced by Angiotensin receptor blockers can still occur even after discontinuing the medication for 48 hours before induction of general anesthesia. Despite withholding the medication, caution should be practiced regarding hypotension during general anesthesia in patient taking ARBs.

Comparison of Efficacy and Safety of Azilsartan and Amlodipine Combination Versus Telmisartan and Amlodipine Combination in Hypertensive Patients: A Non-inferiority Trial

Introduction Hypertension (HTN) is one of the most common conditions encountered in daily practice in hospitals. Combination therapy is mostly initiated in the management of HTN when target blood pressure is not achieved with monotherapy. There are few studies comparing the antihypertensive effect of a combination of azilsartan and amlodipine with a combination of amlodipine and other angiotensin receptor blockers (ARBs), however, the results are contradictory. The objective of this study was to compare the efficacy and safety of the azilsartan and amlodipine combination versus the telmisartan and amlodipine combination in hypertensive patients. Methods The present study was a prospective, randomized, active-controlled, open-label, parallel-group clinical trial. Hypertensive patients were randomized into two groups of 25 patients each. Baseline evaluations of systolic blood pressure (SBP), diastolic blood pressure (DBP), and high-sensitivity troponin I (hsTnI) were done. Patients were reassessed after 12 weeks of drug therapy with azilsartan 40 mg and amlodipine 5 mg combination or telmisartan 40 mg once daily (QD) and amlodipine 5 mg combination QD. Results The response rate (defined as a reduction of more than 20 mm Hg in SBP or 10 mm Hg in DBP or both from baseline at 12 weeks) for HTN in the test group and control groups was found to be 88% and 96% respectively. The response rate of the azilsartan amlodipine group was found to be non-inferior to the telmisartan amlodipine group (odds ratio, OR, 0.31, p = 0.61) at the end of 12 weeks of drug therapy. At 12 weeks of follow-up, there was a significant decrease in SBP (p < 0.001), DBP (p < 0.001), and hsTnI levels (p < 0.001) in both groups from baseline values. However, differences between the test and control groups for blood pressure and hsTnI were found to be not statistically significant at 12 weeks of follow-up. The most commonly reported adverse effect in both groups was headache. Conclusion Azilsartan amlodipine combination had an 88% response rate, which was non-inferior to the telmisartan and amlodipine combination. Biomarkers such as hsTnI showed a significant decrease in both groups after 12 weeks of follow-up. However, there was no significant difference between the two groups.

Palladium-Catalyzed Arylation of C(sp2)-H Bonds with 2-(1-Methylhydrazinyl)pyridine as the Bidentate Directing Group

Palladium-catalyzed C(sp²)-H arylation of ortho C-H bonds involving 2-(1-methylhydrazinyl)pyridine (MHP) as the directing group has been investigated. The reaction proceeds smoothly under an air atmosphere to generate biaryl derivatives in an environmentally friendly manner while tolerating a wide range of functional groups. Notably, the directing group present in the product could be easily removed under mild reductive conditions.

Rational Design and Synthesis of AT1R Antagonists

Hypertension is one of the most common diseases nowadays and is still the major cause of premature death despite of the continuous discovery of novel therapeutics. The discovery of the Renin Angiotensin System (RAS) unveiled a path to develop efficient drugs to fruitfully combat hypertension. Several compounds that prevent the Angiotensin II hormone from binding and activating the AT1R, named sartans, have been developed. Herein, we report a comprehensive review of the synthetic paths followed for the development of different sartans since the discovery of the first sartan, Losartan.

Is the newest angiotensin-receptor blocker azilsartan medoxomil more efficacious in lowering blood pressure than the older ones? A systematic review and network meta-analysis

Angiotensin‐receptor blockers are often considered insufficiently efficacious in reducing blood pressure. However, newer angiotensin‐receptor blockers may be more effective than the older ones. A network meta‐analysis was performed to compare the efficacy of various angiotensin‐receptor blockers in reducing office and ambulatory blood pressure in hypertensive patients. Relevant literature was searched from English and Chinese databases for randomized controlled trials involving angiotensin‐receptor blockers in hypertension. Efficacy variables included systolic and diastolic blood pressure either in the office or on ambulatory blood pressure monitoring. Absolute blood pressure reductions at 6‐12 weeks of treatment and their credible intervals were reported. A total of 34 publications provided adequate data for analysis (n = 14 859). In 28 studies on office systolic blood pressure (n = 12 731), against the common comparator valsartan 80 mg, the differences in systolic blood pressure were in favor of azilsartan medoxomil (20‐80 mg), irbesartan (300 mg), olmesartan (20‐40 mg), telmisartan (80 mg), and valsartan (160‐320 mg), but not candesartan (8‐16 mg), losartan (50‐100 mg), irbesartan (150 mg), olmesartan (10 mg), and telmisartan (40 mg). The ranking plot shows that azilsartan medoxomil 80 mg had a possibility of 99% being the best in the class. Similar results were observed for office diastolic blood pressure and from 13 studies for 24‐hour ambulatory systolic and diastolic blood pressure. In conclusion, angiotensin‐receptor blockers had different blood pressure lowering efficacy. The newest angiotensin‐receptor blocker azilsartan medoxomil at the dose of 80 mg seemed to be most efficacious in reducing both systolic and diastolic blood pressure in the office and on ambulatory measurement.

Prodrugs for Improved Drug Delivery: Lessons Learned from Recently Developed and Marketed Products

Prodrugs are bioreversible, inactive drug derivatives, which have the ability to convert into a parent drug in the body. In the past, prodrugs were used as a last option; however, nowadays, prodrugs are considered already in the early stages of drug development. Optimal prodrug needs to have effective absorption, distribution, metabolism, and elimination (ADME) features to be chemically stable, to be selective towards the particular site in the body, and to have appropriate safety. Traditional prodrug approach aims to improve physicochemical/biopharmaceutical drug properties; modern prodrugs also include cellular and molecular parameters to accomplish desired drug effect and site-specificity. Here, we present recently investigated prodrugs, their pharmaceutical and clinical advantages, and challenges facing the overall prodrug development. Given examples illustrate that prodrugs can accomplish appropriate solubility, increase permeability, provide site-specific targeting (i.e., to organs, tissues, enzymes, or transporters), overcome rapid drug metabolism, decrease toxicity, or provide better patient compliance, all with the aim to provide optimal drug therapy and outcome. Overall, the prodrug approach is a powerful tool to decrease the time/costs of developing new drug entities and improve overall drug therapy.

Azilsartan piperazine salt solvate and monohydrate: preparation, crystal structure, enhanced solubility and oral bioavailability

Two azilsartan–piperazine salt solvates and a monohydrate feature crystal structural diversity and improve the azilsartan solubility over that of the free Az form. Az–Pz·EtOH and Az–Pz·H₂O improve the plasma azilsartan concentration C_max and AUC over the free Az form.

Systematic Review with Network Meta-Analysis: Comparative Efficacy and Safety of Combination Therapy with Angiotensin II Receptor Blockers and Amlodipine in Asian Hypertensive Patients

Background

Hypertension (HTN) is the leading risk factor for cardiovascular mortality globally. The WHO estimates a 60% increase in Asian HTN patients between 2000 and 2025. Numerous studies have compared safety and efficacy between antihypertensive classes, but in-class comparisons of angiotensin II receptor blockers (ARBs) in combination therapy (CT) (fixed-dose combination or dual combination) with a calcium channel blocker (CCB) are lacking in Asia.

Objective

To compare the efficacy and safety of the various ARB-amlodipine CTs and amlodipine (AML) monotherapy for treatment of HTN in Asian population.

Methods

A systematic literature review sourced Asian randomized controlled trials (RCTs) from PubMed and Cochrane Libraries to inform a network meta-analysis (NMA). We considered the ARB-AML CT. The primary efficacy and safety endpoints were short-term (8–12 weeks) treatment response and treatment-emergent adverse events (TEAEs), respectively. AML monotherapy was used as a comparator to allow for indirect treatment effect estimation in the absence of direct RCTs evidence comparing the different ARB-AML CTs.

Results

The analysis included 1198 Asian HTN patients from seven studies involving six ARB-AML CTs: azilsartan (AZL), candesartan (CAN), fimasartan (FIM), losartan (LOS), olmesartan (OLM), and telmisartan (TEL). Compared to AML monotherapy, CT of AZL-AML had five times greater odds of prompting a treatment response (OR 5.2, 95% CI: 2.5, 11.2), while CAN-AML had 3.9 (95% CI: 2.5, 6.4), FIM-AML had 3.4 (95% CI: 1.4, 8.5), TEL-AML had 3.3 (95% CI: 1.6, 7.1), OLM-AML had 2.7 (95% CI: 1.6, 5.0), and LOS-AML had 2.0 (95% CI: 0.6, 7.3). All ARB-AML CTs had safety profiles comparable to AML monotherapy except TEL-AML, which had significantly lower odds of TEAEs (0.26 (95% CI: 0.087, 0.70)).

Conclusion

This study suggests that all ARB-AML CTs compared favorably to AML monotherapy regarding short-term treatment response in uncomplicated HTN patients of Asian origin. AZL-AML prompted the most favorable treatment response. Safety profiles among the ARB-AML CTs were largely comparable. Due to the limited study size and small number of trials (direct evidence), our findings should best be interpreted as an exploratory effort importance to inform future research direction.

Efficacy and safety of different doses of azilsartan medoxomil in patients with hypertension: A protocol of a network meta-analysis

BACKGROUND

Hypertension is one of the most common chronic diseases and an increasingly public-health challenge worldwide. Previous meta-analyses evaluated the effects of azilsartan medoxomil compared to placebo or other antihypertensive drugs in patients with hypertension. However, it is still unclear which dose of azilsartan is optimal. This study will perform a network meta-analysis to assess the efficacy and safety of different doses of azilsartan medoxomil in patients with hypertension.

METHODS

PubMed, EMBASE.com, the Cochrane library, Scopus, and Web of Science were searched from inception to May 2019. Randomized controlled trials reporting efficacy and safety of different doses of azilsartan medoxomil on hypertension will be included if they compared 1 dose of azilsartan medoxomil with another dose of azilsartan medoxomil or with a placebo. Risk of bias of the included trials will be evaluated according to the Cochrane Handbook 5.1.0. NMA will be performed in a Bayesian hierarchical framework using WinBUGS 14.

RESULTS

The results will be submitted to a peer-reviewed journal for publication.

CONCLUSION

This study will summarize all the available data to provide reliable evidence of the value of different doses of azilsartan medoxomil for the treatment of hypertension.

PROSPERO REGISTRATION NUMBER

CRD42019136882.

Stability-Indicating RP-UPLC Method for Simultaneous Determination of Azilsartan Medoxomil and Chlorthalidone in Tablets in the Presence of Its Degradation Products

Azilsartan Medoxomil (AZL) angiotensin II receptor blocker and chlorthalidone (CLT) were determined by ultraperformance liquid chromatography (UPLC) method in their combined dosage form, they were both subjected to forced degradation studies under extensive stress conditions. The method is a stability indicating by resolving the investigated drugs from their degradation products. Moreover, the degradation products for both drugs obtained from forced degradation were subjected to LC-MS for structure elucidation. The UPLC technique depends on the measurement of spectra for AZL and CLT at 254 nm. Linearity, accuracy and intermediate precision were acceptable over the concentration range of 67.2-268.8 and 40-160 μg/mL for AZL and CLT, respectively. The method was applied for the determination of the studied drugs in their dosage forms. The UPLC method is inexpensive, simple and considered as green chemistry method for the routine analysis and quality control of both drugs in their combined dosage form.

microRNA-21 and hypertension

Hypertension, a multifactorial disease, is a major risk factor for the development of stroke, coronary artery disease, heart failure, and chronic renal failure. However, its underlying cellular and molecular mechanisms remain largely elusive. Numerous studies have shown that microRNAs (miRNAs) are involved in a variety of cellular processes, including cellular proliferation, apoptosis, differentiation, and the development of diseases. microRNA-21 (miR-21), a conserved single-stranded non-coding RNA that is composed of approximately 22 nucleotides, is one of the most intensively studied miRNAs in recent years, and it can regulate gene expression at the post-transcriptional level. miR-21 is expressed in many kinds of tumors and in the cardiovascular system, and it plays an important role in the occurrence and development of cardiovascular diseases. In recent years, more and more evidence indicates that miR-21 plays an important role in hypertension. This article reviews the source, function, and altered levels of miR-21 in hypertension and the role of miR-21 in the pathogenesis of hypertension and target organ damage (TOD). The potential role of miR-21 as a new target for predicting and treating hypertension is also explored.

Antihypertensive effect of azilsartan versus olmesartan in patients with essential hypertension: a meta-analysis

OBJECTIVE

The comparison of antihypertensive effects between azilsartan and olmesartan in patients with essential hypertension has been investigated in several studies. The results were not consistent. We performed this meta-analysis determining the antihypertensive effect of azilsartan versus olmesartan in patients with essential hypertension.

METHODS

Pubmed, Web of Science, and Cochrane Central were searched for all published randomized studies comparing the antihypertensive effects between azilsartan and olmesartan in patients with essential hypertension.

RESULTS

The antihypertensive effects were assessed in 1402 patients included in five trials. The reduction of office systolic blood pressure treated with azilsartan was greater than olmesartan (weighted mean differences (WMD) - 2.15 (95% confidence interval (CI), - 3.78, - 0.53) mm Hg, p < 0.01). There was no significant difference in reduction of office diastolic blood pressure between azilsartan and olmesartan (WMD - 0.99 (95% CI, - 2.06, 0.08) mm Hg, p > 0.05). The reduction of office systolic blood pressure treated with azilsartan was greater than olmesartan at same dose for both drugs (WMD - 2.24 (95% CI, - 4.03, - 0.44) mm Hg, p < 0.05), whereas there was no significant difference in reduction of office diastolic blood pressure between azilsartan and olmesartan (WMD - 0.55 (95% CI, - 1.76, 0.66) mm Hg, p > 0.05).

CONCLUSIONS

This meta-analysis provides the evidence that the reduction of office systolic blood pressure treated with azilsartan was greater than olmesartan in patients with essential hypertension. These findings suggest the importance of strict designed randomized controlled trials in determining antihypertensive effects of angiotensin II receptor blockers in clinical practice.

Divergent Spatiotemporal Interaction of Angiotensin Receptor Blocking Drugs with Angiotensin Type 1 Receptor

Crystal structures of the human angiotensin II type 1 receptor (AT₁R) complex with the antihypertensive agent ZD7155 (PDB id: 4YAY ) and the blood pressure medication Benicar (PDB id: 4ZUD ) showed that binding poses of both antagonists are similar. This finding implies that clinically used angiotensin receptor blocking (ARB) drugs may interact in a similar fashion. However, clinically observed differences in pharmacological and therapeutic efficacies of ARBs lead to the question of whether the dynamic interactions of AT₁R with ARBs vary. To address this, we performed induced-fit docking (IFD) of eight clinically used ARBs to AT₁R followed by 200 ns molecular dynamic (MD) simulation. The experimental K_i values for ARBs correlated remarkably well with calculated free energy with R² = 0.95 and 0.70 for AT₁R-ARB models generated respectively by IFD and MD simulation. The eight ARB-AT₁R complexes share a common set of binding residues. In addition, MD simulation results validated by mutagenesis data discovered distinctive spatiotemporal interactions that display unique bonding between an individual ARB and AT₁R. These findings provide a reasonably broader picture reconciling the structure-based observations with clinical studies reporting efficacy variations for ARBs. The unique differences unraveled for ARBs in this study will be useful for structure-based design of the next generation of more potent and selective ARBs.

Improvement of Diurnal Blood Pressure Variation by Azilsartan

Background

Azilsartan is an angiotensin II receptor blocker with a potent antihypertensive effect.

Methods

In a multicenter, prospective, open-label study, 265 patients with poor blood pressure control despite treatment with other angiotensin II receptor blockers were switched to 20 mg/day of azilsartan (patients on standard dosages) or 40 mg/day of azilsartan (patients on high dosages).

Results

Blood pressure was 149/83 mm Hg before switching and was significantly reduced from 1 month after switching until final assessment (132/76 mm Hg, P < 0.001). The pulse rate was 72/min before switching and increased significantly from 3 months after switching until final assessment (74/min, P < 0.005). A significant decrease of home morning systolic and diastolic pressure was observed from 1 and 3 months, respectively. Home morning blood pressure was 143/82 mm Hg before switching and 130/76 mm Hg at final assessment (P < 0.01). The morning-evening difference of systolic blood pressure decreased from 14.6 to 6.6 mm Hg after switching (P = 0.09). The estimated glomerular filtration rate was significantly decreased at 3, 6, and 12 months after switching, and serum uric acid was significantly increased at 12 months. No serious adverse events occurred.

Conclusion

Azilsartan significantly reduced the blood pressure and decreased diurnal variation in patients responding poorly to other angiotensin II receptor blockers.

A Practical Approach to Hypertension Management in Diabetes

Hypertension is one of the most important comorbidities of diabetes, contributing significantly to death and disability and leads to macrovascular and microvascular complications. When assessing the medical priorities for patients with diabetes, treating hypertension should be a primary consideration. Practical approaches to hypertension in diabetes, including individualized targets are discussed, as per stage and complication of diabetes, according to current studies and guidelines. Angiotensin converting enzyme inhibitors (ACEI)/angiotensin receptor blockers (ARBs) are the most effective drugs for treating hypertension in diabetes, in the absence of contraindications. Calcium antagonists or diuretics are acceptable as second-line agents. Once the target is achieved, antihypertensive drugs should be continued. Newer antidiabetes medications such as sodium glucose cotransporter-2 inhibitors (SGLT2i), glucagon-like peptide-1 receptor agonists (GLP1-RA), and dipeptidyl peptidase-4 inhibitors (DPP4i) have antihypertensive properties and may assist in treatment decision-making.

Evaluation of the angiotensin II receptor blocker azilsartan medoxomil in African‐American patients with hypertension

The efficacy and safety of azilsartan medoxomil (AZL‐M) were evaluated in African‐American patients with hypertension in a 6‐week, double‐blind, randomized, placebo‐controlled trial, for which the primary end point was change from baseline in 24‐hour mean systolic blood pressure (BP). There were 413 patients, with a mean age of 52 years, 57% women, and baseline 24‐hour BP of 146/91 mm Hg. Treatment differences in 24‐hour systolic BP between AZL‐M 40 mg and placebo (−5.0 mm Hg; 95% confidence interval, −8.0 to −2.0) and AZL‐M 80 mg and placebo (−7.8 mm Hg; 95% confidence interval, −10.7 to −4.9) were significant (P≤.001 vs placebo for both comparisons). Changes in the clinic BPs were similar to the ambulatory BP results. Incidence rates of adverse events were comparable among the treatment groups, including those of a serious nature. In African‐American patients with hypertension, AZL‐M significantly reduced ambulatory and clinic BPs in a dose‐dependent manner and was well tolerated.

Advances in understanding the renin-angiotensin-aldosterone system (RAAS) in blood pressure control and recent pivotal trials of RAAS blockade in heart failure and diabetic nephropathy

The renin-angiotensin-aldosterone system (RAAS) plays a fundamental role in the physiology of blood pressure control and the pathophysiology of hypertension (HTN) with effects on vascular tone, sodium retention, oxidative stress, fibrosis, sympathetic tone, and inflammation. Fortunately, RAAS blocking agents have been available to treat HTN since the 1970s and newer medications are being developed. In this review, we will (1) examine new anti-hypertensive medications affecting the RAAS, (2) evaluate recent studies that help provide a better understanding of which patients may be more likely to benefit from RAAS blockade, and (3) review three recent pivotal randomized trials that involve newer RAAS blocking agents and inform clinical practice.

The Impact of Azilsartan Medoxomil Treatment (Capsule Formulation) at Doses Ranging From 10 to 80 mg: Significant, Rapid Reductions in Clinic Diastolic and Systolic Blood Pressure

In this phase 2, multicenter, parallel-group, double-blind, dose-ranging study, hypertensive adults (n=449) were randomized to receive one of five doses of a capsule formulation of azilsartan medoxomil (AZL-M; 5, 10, 20, 40, 80 mg), olmesartan medoxomil (OLM) 20 mg, or placebo once daily. The primary endpoint was change in trough clinic diastolic blood pressure (DBP) at week 8. AZL-M provided rapid statistically and clinically significant reductions in DBP and systolic blood pressure (SBP) vs placebo at all doses except 5 mg. Placebo-subtracted changes were greatest with the 40 mg dose (DBP, -5.7 mm Hg; SBP, -12.3 mm Hg). Clinic changes with AZL-M (all doses) were statistically indistinguishable vs OLM, although there were greater reductions with AZL-M 40 mg using 24-hour ambulatory blood pressure. Adverse event frequency was similar in the AZL-M and placebo groups. Based on these and other findings, subsequent trials investigated the commercial AZL-M tablet in the dose range of 20 to 80 mg/d.

Azilsartan as a Potent Antihypertensive Drug with Possible Pleiotropic Cardiometabolic Effects: A Review Study

Background: Hypertension related cardiovascular (CV) complications could be amplified by the presence of metabolic co-morbidities. Azilsartan medoxomil (AZL-M) is the eighth approved member of angiotensin II receptor blockers (ARBs), a drug class of high priority in the management of hypertensive subjects with diabetes mellitus type II (DMII).

Methods: Under this prism, we performed a systematic review of the literature for all relevant articles in order to evaluate the efficacy, safety, and possible clinical role of AZL-M in hypertensive diabetic patients.

Results: AZL-M was found to be more effective in terms of reducing indices of blood pressure over alternative ARBs or angiotensin-converting enzyme (ACE) inhibitors with minimal side effects. Preclinical studies have established pleiotropic effects for AZL-M beyond its primary antihypertensive role through differential gene expression, up-regulation of membrane receptors and favorable effect on selective intracellular biochemical and pro-atherosclerotic pathways.

Conclusion: Indirect but accumulating evidence from recent literature supports the efficacy and safety of AZL-M among diabetic patients. However, no clinical data exist to date that evince a beneficial role of AZL-M in patients with metabolic disorders on top of its antihypertensive effect. Further clinical studies are warranted to assess the pleiotropic cardiometabolic benefits of AZL-M that are derived from preclinical research.

Azilsartan in Patients With Mild to Moderate Hypertension Using Clinic and Ambulatory Blood Pressure Measurements

This was a phase 2, multicenter, randomized, parallel-group, double-blind dose-ranging study. Hypertensive adults (n=555) received one of five doses of azilsartan (AZL; 2.5, 5, 10, 20, 40 mg), olmesartan medoxomil (OLM) 20 mg, or placebo once daily. The primary endpoint was change in trough clinic diastolic blood pressure (DBP) at week 8. Compared with placebo, all AZL doses (except 2.5 mg) provided statistically and clinically significant reductions in DBP and systolic blood pressure (SBP) based on both clinic blood pressure (BP) and 24-hour ambulatory BP monitoring (ABPM). AZL 40 mg was statistically superior vs OLM. Clinic BP was associated with a pronounced placebo effect (-6 mm Hg), whereas this was negligible with ABPM (±0.5 mm Hg). Adverse event frequency was similar in the AZL and placebo groups. Based on these and other findings, subsequent trials investigated the commercial AZL medoxomil tablet at doses 20 to 80 mg/d using 24-hour ABPM.

Changeover Trial of Azilsartan and Olmesartan Comparing Effects on the Renin-Angiotensin-Aldosterone System in Patients with Essential Hypertension after Cardiac Surgery (CHAOS Study)

BACKGROUND

Angiotensin II receptor blockers (ARBs) have been widely used to treat hypertension and large-scale clinical studies have shown various benefits. In this study, we compared olmesartan with azilsartan, the newest ARB.

METHODS

The subjects were outpatients who were clinically stable after cardiac surgery. Sixty patients were randomized to receive either azilsartan or olmesartan for 1 year and were switched to the other drug for the following 1 year. The primary endpoints were the levels of plasma renin activity, angiotensin II, and aldosterone.

RESULTS

Home blood pressure exceeded 140/90 mmHg and additional antihypertensive medication was administered to 12 patients (20 episodes) in the azilsartan group versus 4 patients (4 episodes) in the olmesartan group, with the number being significantly higher in the azilsartan group. After 1 year of treatment, both angiotensin II and aldosterone levels were significantly lower in the olmesartan group than the azilsartan group. Left ventricular mass index was also significantly lower in the olmesartan group than the azilsartan group.

CONCLUSION

This study showed that olmesartan reduces angiotensin II and aldosterone levels more effectively than azilsartan. Accordingly, it may be effective in patients with increased renin-angiotensin-aldosterone system activity after cardiac surgery or patients with severe cardiac hypertrophy.

Azilsartan compared to ACE inhibitors in anti-hypertensive therapy: one-year outcomes of the observational EARLY registry

BACKGROUND

Azilsartan medoxomil (AZL-M), has been demonstrated to be more effective than the other sartans currently in use; however, there is insufficient information available comparing it with ACE-inhibitors. Therefore, we aimed to compare the efficacy, safety, and tolerability of AZL-M with that of ACE-inhibitors in a real life clinical setting.

METHODS

The EARLY registry is a prospective, observational, national, multicentre registry with a follow-up period of 12 months. There were two principal objectives: 1) documentation of the achievement of target BP values set according to recent national and international guidelines, and 2) description of the safety profile of AZL-M.

RESULTS

A total of 3 849 patients with essential arterial hypertension were recruited from primary care offices in Germany. Patients who initiated monotherapy at baseline comprising either AZL-M or an ACE-inhibitor were included at a ratio of seven to three. Results demonstrated that a blood pressure target of <140/90 mmHg was achieved by a significantly greater proportion of patients in the AZL-M group (61.1 %) compared with the ACE-inhibitor group (56.4 %; p < 0.05; OR, 1.21; 95 % CI, 1.03-1.42), with this finding maintained after adjusting for differences in baseline characteristics. AZL-M appeared to have an equivalent safety profile to the ACE-inhibitors, with a similar incidence of adverse events in the two patient groups (p = 0.73).

CONCLUSIONS

These data add to the results of previous randomized controlled clinical trials suggesting that, compared with other agents that target the renin-angiotensin system, AZL-M provides statistically significant albeit small improvements in blood pressure control.

Azilsartan Improves Salt Sensitivity by Modulating the Proximal Tubular Na+-H+ Exchanger-3 in Mice

A potent angiotensin II type-1 receptor blocker, azilsartan, has been reported to reduce blood pressure more effectively than candesartan. Interestingly, azilsartan can also restore the circadian rhythm of blood pressure. We hypothesized that azilsartan could also improve salt sensitivity; thus, we examined the effect of azilsartan on sodium handling in renal tubules. Subtotal nephrectomized C57BL/6 mice received azilsartan (1.0 mg/kg/day), candesartan (0.3 mg/kg/day), or vehicle via the oral route in conjunction with a normal- (0.3%) or high-salt (8.0%) diet. Two weeks later, the azilsartan group showed significantly lower blood pressure during the light period than the candesartan and vehicle groups (azilsartan: 103.1 ± 1.0; candesartan: 111.7 ± 2.7; vehicle: 125.5 ± 2.5 mmHg; P < 0.05; azilsartan or candesartan vs. vehicle). The azilsartan group also showed higher urinary fractional excretion of sodium during the dark period than the candesartan and vehicle groups (azilsartan: 21.37 ± 3.69%; candesartan: 14.17 ± 1.42%; vehicle: 13.85 ± 5.30%; P < 0.05 azilsartan vs. candesartan or vehicle). A pressure—natriuresis curve demonstrated that azilsartan treatment restored salt sensitivity. Immunofluorescence and western blotting showed lower levels of Na⁺-H⁺ exchanger-3 (NHE3) protein (the major sodium transporter in renal proximal tubules) in the azilsartan group, but not in the candesartan or vehicle groups. However, azilsartan did not affect NHE3 transcription levels. Interestingly, we did not observe increased expression of downstream sodium transporters, which would have compensated for the increased flow of sodium and water due to non-absorption by NHE3. We also confirmed the mechanism stated above using cultured opossum kidney proximal tubular cells. Results revealed that a proteasomal inhibitor (but not a lysosomal inhibitor) blocked the azilsartan-induced decrease in NHE3 protein expression, suggesting that azilsartan increases NHE3 ubiquitination. In conclusion, azilsartan (but not candesartan) improved salt sensitivity possibly by decreasing NHE3 expression via ubiquitin—proteasomal degradation.

New developments in the pharmacological treatment of hypertension: dead-end or a glimmer at the horizon?

Arterial hypertension is the most prevalent controllable disease world-wide. Yet, we still need to further improve blood pressure control, deal with resistant hypertension, and we hope to reduce risk "beyond blood pressure." The number of candidate molecules aspiring for these aims is constantly declining. The new possible approaches to combat high blood pressure include neprilysin/neutral endopeptidase (NEP) inhibition, particularly when combined with an angiotensin receptor blockade (such as the ARNI, LCZ696), phosphodiesterase 5 (PDE5) inhibition (KD027/Slx-2101), natriuretic agents (PL3994), or a long-lasting vasointestinal peptide (VIP) analogue (PB1046). Other options exploit the protective arm of the renin-angiotensin-aldosterone system by stimulating the angiotensin AT2 receptor (compound 21), the Mas receptor (AVE-0991), or the angiotensin converting enzyme 2. Finally, we review the possibilities how to optimize the use of the available treatment options by using drug combinations or by tailoring therapy to each patient's angiotensin peptide profile.

Safety, tolerability, and efficacy of azilsartan medoxomil with or without chlorthalidone during and after 8 months of treatment for hypertension

A phase 3, 26‐week, open‐label, titrate‐to‐target study (n=418) assessed the safety of azilsartan medoxomil (AZL‐M) alone and with chlorthalidone (CLD), followed by a 6‐week, double‐blind, placebo‐controlled reversal phase with change in clinic diastolic blood pressure (DBP) as the primary endpoint. Target blood pressure (BP) was <140/90 mm Hg (<130/80 mm Hg with diabetes/chronic kidney disease). AZL‐M was initiated at 40 mg once a day (QD), force‐titrated to 80 mg at week 4. CLD 25 mg QD could be added (weeks 8–22), if required, to reach target, followed by additional antihypertensives from week 12. At the end of the open‐label phase, mean change in systolic BP (SBP)/DBP from baseline was −23/−16 mm Hg. The most common adverse events, irrespective of treatment, were dizziness (8.9%) and headache (7.2%). Serious AEs were reported in eight patients (1.9%). Consecutive creatinine elevations ≥50% with values exceeding the upper limit of normal (ULN) were reported in nine (2.2%) patients. All returned to below the 50% threshold; most also returned to below the ULN after drug discontinuation. Mean DBP was maintained through the reversal phase in patients receiving AZL‐M, but increased with placebo (difference: −7.8 mm Hg, 95% confidence interval, −9.8 to −5.8; P<.001). AZL‐M alone or with CLD showed good long‐term safety and stable BP improvements in a titrate‐to‐target approach. BP improvements caused by AZL‐M therapy were safely reversible upon AZL‐M withdrawal.

Azilsartan improves glycemic status and reduces kidney damage in zucker diabetic fatty rats

BACKGROUND

Azilsartan medoxomil (AZL-M), an angiotensin II receptor blocker, demonstrates antihypertensive and organ protective effects in hypertension. We investigated the efficacy of AZL-M to ameliorate metabolic syndrome and kidney damage associated with type 2 diabetes using Zucker diabetic fatty (ZDF) rats.

METHODS

ZDF rats were treated with vehicle or AZL-M for 8 weeks. Zucker diabetic lean (ZDL) rats were used as controls. Urine and plasma samples were collected for biochemical analysis, and kidney tissues were used for histopathological and immunohistopathological examination at the end of the 8-week protocol.

RESULTS

ZDF rats were diabetic with hyperglycemia and impaired glucose tolerance, and AZL-M ameliorated the diabetic phenotype. ZDF rats were hypertensive compared with ZDL rats (181±6 vs. 129±7mm Hg), and AZL-M decreased blood pressure in ZDF rats (116±7mm Hg). In ZDF rats, there was marked renal damage with elevated proteinuria, albuminuria, nephrinuria, 2-4-fold higher tubular cast formation, and glomerular injury compared with ZDL rats. AZL-M treatment reduced renal damage in ZDF rats. ZDF rats demonstrated renal inflammation and oxidative stress with elevated urinary monocyte chemoattractant protein 1 excretion, renal infiltration of macrophages, and elevated kidney malondialdehyde levels. AZL-M reduced oxidative stress and inflammation in ZDF rats.

CONCLUSIONS

Overall, we demonstrate that AZL-M attenuates kidney damage in type 2 diabetes. We further demonstrate that anti-inflammatory and antioxidative activities of AZL-M contribute to its kidney protective action.

Spectrophotometric and spectrofluorimetric studies on azilsartan medoxomil and chlorthalidone to be utilized in their determination in pharmaceuticals

The recently approved angiotensin II receptor blocker, azilsartan medoxomil (AZL), was determined spectrophotometrically and spectrofluorimetrically in its combination with chlorthalidone (CLT) in their combined dosage form. The UV-spectrophotometric technique depends on simultaneous measurement of the first derivative spectra for AZL and CLT at 286 and 257 nm, respectively, in methanol. The spectrofluorimetric technique depends on measurement of the fourth derivative of the synchronous spectra intensities of AZL in presence of CLT at 298 nm in methanol. The effects of different solvents on spectrophotometric and spectrofluorimetric responses were studied. For, the spectrofluorimetric study, the effect of pH and micelle-assisted fluorescence enhancement were also studied. Linearity, accuracy, and precision were found to be satisfactory over the concentration ranges of 8–50 μg mL⁻¹ and 2–20 μg mL⁻¹ for AZL and CLT, respectively, in the spectrophotometric method as well as 0.01–0.08 μg mL⁻¹ for AZL in the spectrofluorimetric method. The methods were successfully applied for the determination of the studied drugs in their co-formulated tablets. The developed methods are inexpensive and simple for the quality control and routine analysis of the cited drugs in bulk and in pharmaceuticals.

Azilsartan, an angiotensin II type 1 receptor blocker, restores endothelial function by reducing vascular inflammation and by increasing the phosphorylation ratio Ser(1177)/Thr(497) of endothelial nitric oxide synthase in diabetic mice

BACKGROUND

Azilsartan, an angiotensin II type 1 (AT1) receptor blocker (ARB), has a higher affinity for and slower dissociation from AT1 receptors and shows stronger inverse agonism compared to other ARBs. Possible benefits of azilsartan in diabetic vascular dysfunction have not been established.

METHODS

We measured vascular reactivity of aortic rings in male KKAy diabetic mice treated with vehicle, 0.005% azilsartan, or 0.005% candesartan cilexetil for 3 weeks. Expression of markers of inflammation and oxidative stress was measured using semiquantitative RT-PCR in the vascular wall, perivascular fat, and skeletal muscle. Phosphorylation of endothelial nitric oxide synthase (eNOS) at Ser1177 and Thr495 was measured using Western blotting, and the ratio of phosphorylation at Ser1177 to phosphorylation at Thr495 was used as a putative indicator of vascular eNOS activity.

RESULTS

(1) Vascular endothelium-dependent relaxation with acetylcholine in KKAy mice was improved by azilsartan treatment compared to candesartan cilexetil; (2) the ratio of Ser1177/Thr495 phosphorylation of eNOS was impaired in KKAy and was effectively restored by azilsartan; (3) anomalies in the expression levels of monocyte chemotactic protein 1 (MCP1), F4/80, NAD(P)H oxidase (Nox) 2, and Nox4 of the aortic wall and in the expression of TNFα in the perivascular fat were strongly attenuated by azilsartan compared to candesartan cilexetil.

CONCLUSIONS

These results provide evidence that azilsartan prevents endothelial dysfunction in diabetic mice, more potently than does candesartan cilexetil. Azilsartan's higher affinity for and slower dissociation from AT1 receptors may underlie its efficacy in diabetic vascular dysfunction via a dual effect on uncoupled eNOS and on Nox.

Azilsartan medoxomil in the treatment of hypertension: the definitive angiotensin receptor blocker?

INTRODUCTION

Azilsartan medoxomil is the newest angiotensin receptor blocker marketed for the treatment of arterial hypertension. The aim of this article was to review the available evidence about this drug alone or combined with other antihypertensive agents in the treatment of hypertensive population.

AREAS COVERED

For this purpose, a search on MEDLINE and EMBASE databases was performed. The MEDLINE and EMBASE search included both medical subject headings (MeSHs) and keywords including azilsartan or azilsartan medoxomil or angiotensin receptor blockers or renin angiotensin system or chlorthalidone and hypertension. References of the retrieved articles were also screened for additional studies. There were no language restrictions.

EXPERT OPINION

Azilsartan medoxomil has a potent and persistent ability to inhibit binding of angiotensin II to AT1 receptors, which may play a role in its superior blood pressure (BP) -lowering efficacy compared with other drugs, including ramipril, candesartan, valsartan or olmesartan, without an increase of side effects. Chlortalidone is a diuretic which significantly differs from other classic thiazides and has largely demonstrated clinical benefits in outcome trials. The fixed-dose combination of azilsartan and chlorthalidone has been shown to be more effective than other potent combinations of angiotensin receptor blockers plus hydrochlorothiazide, with a good tolerability profile.

Novel mechanism for disrupted circadian blood pressure rhythm in a rat model of metabolic syndrome--the critical role of angiotensin II

BACKGROUND

This study was performed to determine the characteristics and mechanism of hypertension in SHR/NDmcr-cp(+/+) rats (SHRcp), a new model of metabolic syndrome, with a focus on the autonomic nervous system, aldosterone, and angiotensin II.

METHODS AND RESULTS

We measured arterial blood pressure (BP) in SHRcp by radiotelemetry combined with spectral analysis using a fast Fourier transformation algorithm and examined the effect of azilsartan, an AT1 receptor blocker. Compared with control Wistar-Kyoto rats (WKY) and SHR, SHRcp exhibited a nondipper-type hypertension and displayed increased urinary norepinephrine excretion and increased urinary and plasma aldosterone levels. Compared with WKY and SHR, SHRcp were characterized by an increase in the low-frequency power (LF) of systolic BP and a decrease in spontaneous baroreflex gain (sBRG), indicating autonomic dysfunction. Thus, SHRcp are regarded as a useful model of human hypertension with metabolic syndrome. Oral administration of azilsartan once daily persistently lowered BP during the light period (inactive phase) and the dark period (active phase) in SHRcp more than in WKY and SHR. Thus, angiotensin II seems to be involved in the mechanism of disrupted diurnal BP rhythm in SHRcp. Azilsartan significantly reduced urinary norepinephrine and aldosterone excretion and significantly increased urinary sodium excretion in SHRcp. Furthermore, azilsartan significantly reduced LF of systolic BP and significantly increased sBRG in SHRcp.

CONCLUSIONS

These results strongly suggest that impairment of autonomic function and increased aldosterone in SHRcp mediate the effect of angiotensin II on circadian blood pressure rhythms.

An evaluation of the latest evidence relating to renin-angiotensin system inhibitors

INTRODUCTION

In the last few years, a number of important clinical trials have been completed that have investigated the inhibition of the renin-angiotensin system. New drugs, focusing on this system, have now emerged as a result.

AREAS COVERED

The authors review the most relevant information available, reported from the last 5 years, pertaining to the most important clinical trials on renin-angiotensin system blockers (ARBs). The authors' data review includes the trials of aliskiren, telmisartan, olmesartan and azilsartan. The authors also review the possible risk of cancer with ARBs.

EXPERT OPINION

The results of ASPIRE and ALTITUDE trials strongly suggested that dual inhibition of aliskiren with either ARBS or angiotensin converting enzyme inhibitors (ACEi) should be avoided. Olmesartan is an effective and safe antihypertensive agent, but special attention should be paid to high-risk patients, such as those with coronary disease, to avoid an excessive reduction in blood pressure. The authors also note that while azilsartan is probably the most potent ARB, there is still a lack of data regarding potential organ damage and the incidence of cardiovascular events. Lastly, recent evidence has shown a lack of a relationship between ARB therapy and the occurrence of cancer.

Azilsartan medoxomil: a review of its use in hypertension

Azilsartan medoxomil (Edarbi®; Ipreziv™) is an orally administered angiotensin II receptor type 1 antagonist (blocker) used in the treatment of adults with essential hypertension. This article reviews data on the clinical efficacy and tolerability of azilsartan medoxomil in adults with essential hypertension and provides a summary of its pharmacological properties. Azilsartan medoxomil is a prodrug that undergoes rapid hydrolysis in the gastrointestinal tract after oral administration to the bioactive moiety azilsartan, before systemic absorption. Azilsartan medoxomil produces antihypertensive effects by selectively blocking the binding of angiotensin II to the angiotensin type 1 (AT(1)) receptor, thereby antagonizing the pressor response activity of angiotensin II. In vitro, azilsartan produced greater and more sustained AT(1) receptor binding/blockade activity than several comparator angiotensin II receptor antagonists. Azilsartan medoxomil reduces blood pressure (BP) in hypertensive adults. In addition, the drug has been shown to have pleiotropic effects (i.e. effects beyond AT(1) receptor blockade). In adults with essential hypertension, azilsartan medoxomil 20, 40 or 80 mg effectively reduced BP over a 24-hour period with once-daily administration in three major, randomized, controlled trials in which the primary endpoints were changes from baseline in 24-hour mean systolic BP (SBP) at week 6 (two trials) or week 24, assessed by ambulatory BP monitoring (ABPM). In the two 6-week trials, azilsartan medoxomil showed dose-dependent efficacy over all evaluated dosages and was more effective than placebo in lowering SBP. At the maximum approved dosage of 80 mg once daily, azilsartan medoxomil was significantly more effective than maximum dosages of olmesartan medoxomil (40 mg once daily) or valsartan (320 mg once daily), based on primary endpoint assessments. Mean reductions in clinic measurements of SBP and diastolic BP (DBP) measurements were also generally greater with azilsartan medoxomil 80 mg once daily than with the comparator drugs in these 6-week studies. Over a longer treatment period of 24 weeks, azilsartan medoxomil showed sustained BP-lowering efficacy, with the reduction in 24-hour mean SBP at week 24 significantly greater with azilsartan medoxomil 40 or 80 mg once daily than with valsartan 320 mg once daily. Mean reductions from baseline in mean clinic SBP and DBP as well as DBP by ABPM were also significantly greater with azilsartan medoxomil 40 or 80 mg once daily than with valsartan. Azilsartan medoxomil was generally well tolerated, with a tolerability profile similar to that of placebo in the 6-week trials. Across the three major trials, headache and dizziness were among the most common adverse events. Overall, rates of treatment discontinuation as a result of adverse events were low in the 6-week and 24-week trials. In conclusion, once-daily azilsartan medoxomil effectively lowers BP in adults with essential hypertension and has shown better antihypertensive efficacy than maximum therapeutic dosages of olmesartan medoxomil or valsartan in major trials of up to 24 weeks' duration. Azilsartan medoxomil is generally well tolerated and the low rates of discontinuation due to adverse events suggest that patients are likely to persist with long-term treatment. Azilsartan medoxomil is therefore a useful and attractive new option for lowering BP in patients with essential hypertension, particularly for those not able to tolerate other antihypertensive drugs. Further studies are required to evaluate the effects of azilsartan medoxomil on cardiovascular morbidity and mortality.