Drugs for hypertension

American College of Cardiology/American Heart Association (ACC/AHA) guidelines for treatment of hypertension were last published in 2018.1 Treatment of hypertensive urgencies and emergencies is not discussed here.

Comparison of sacubitril/valsartan with olmesartan for hypertension: A meta-analysis of randomized controlled trials

INTRODUCTION

The efficacy of sacubitril/valsartan versus olmesartan remains controversial for the control of hypertension. We conduct a systematic review and meta-analysis to explore the influence of sacubitril/valsartan versus olmesartan on the control of hypertension.

METHODS

We have searched PubMed, Embase, Web of science, EBSCO, and Cochrane library databases through July 2023 for randomized controlled trials assessing the effect of sacubitril/valsartan versus olmesartan on the control of hypertension. This meta-analysis is performed using the random-effect model or fixed-effect model based on the heterogeneity.

RESULTS

Seven randomized controlled trials and 3677 patients were included in the meta-analysis. Overall, compared with olmesartan treatment for hypertension, sacubitril/valsartan treatment was associated with substantially decreased systolic blood pressure (mean difference [MD] = -4.58; 95% confidence interval [CI] = -7.90 to -1.25; P = .007), diastolic blood pressure (MD = -1.70; 95% CI = -3.24 to -0.17; P = .03), and pulse pressure (MD = -2.31; 95% CI = -4.41 to -0.21; P = .03), as well as improved systolic blood pressure control (odds ratio [OR] = 1.65; 95% CI = 1.15 to 2.38; P = .006), but had no influence on diastolic blood pressure control (OR = 1.33; 95% CI = 0.93 to 1.88; P = .11) or adverse events (OR = 1.06; 95% CI = 0.90 to 1.24; P = .51).

CONCLUSIONS

Sacubitril/valsartan is better than olmesartan for the reduction of blood pressure for patients with hypertension.

Olmesartan-Induced Enteropathy: When the Treatment of One Disease Causes Another

Olmesartan is an angiotensin II receptor antagonist used for the management of hypertension. This drug can lead to an enteropathy that clinically and histologically resembles coeliac disease. Symptoms may appear months or years after the introduction of the drug and usually resolve after discontinuation. The authors present a case of an 86-year-old woman with hypertension who was treated with olmesartan for 10 years. She presented to the emergency department with diarrhoea after three months of development and weight loss. The aetiological study that was conducted excluded infectious, inflammatory, endocrinological, and neoplastic causes. The pathological anatomy of the duodenal biopsy was suggestive of coeliac disease, but the serology was not compatible. The patient presented complete remission of the condition with the suspension of the drug and subsequent recrudescence when, by self-initiation, she resumed olmesartan. This case study aims to alert readers of a rare cause of enteropathy with a clinical manifestation that mimics coeliac disease. Olmesartan-induced enteropathy seems to be a diagnosis of exclusion and should be considered in patients chronically medicated with olmesartan.

Efficacy and Safety Comparative of Sacubitril/Valsartan vs. Olmesartan in the Treatment of hypertension: A Meta-analysis of RCTs

BACKGROUND

Sacubitril/valsartan (LCZ696) is a widely used drug for hypertension in Asia, popular for its efficacy and safety. However, there has been no comprehensive literature review comparing it with olmesartan. This meta-analysis compared the antihypertensive and adverse effects of sacubitril/valsartan and olmesartan.

METHODS

We conducted a comprehensive search of Pubmed, Web of Science, Embase, Cochrane Library, and ClinicalTrials.gov databases to identify eligible randomized controlled trials (RCTs). The data were then analyzed and processed using Revman 5.4 and Stata SE14 software.

RESULTS

Six RCTs with 4,127 patients were identified, showing that LCZ696 had better blood pressure control than olmesartan; mean sitting systolic and diastolic blood pressure, sitting pulse pressure, 24-hour ambulatory systolic blood pressure, and 24-hour ambulatory diastolic blood pressure were significantly decreased with LCZ696 compared with olmesartan. No significant difference between LCZ696 and olmesartan was observed in the occurrence of the majority of adverse events, with a decreased probability of headache in patients with sacubitril/valsartan compared with olmesartan. The subgroup analysis showed treatment with 400 mg/d LCZ696 was better than olmesartan in reducing serious adverse events.

CONCLUSIONS

Sacubitril/valsartan was better than olmesartan in controlling blood pressure in patients with hypertension, with relatively higher safety.

Impact of Sex and Genetic Variation in Relevant Pharmacogenes on the Pharmacokinetics and Safety of Valsartan, Olmesartan and Hydrochlorothiazide

Drug combination therapy is the most common pharmacological strategy for hypertension management. No pharmacogenetic biomarkers for guiding hypertension pharmacotherapy are available to date. The study population were 64 volunteers from seven bioequivalence trials investigating formulations with valsartan, olmesartan and/or hydrochlorothiazide. Every volunteer was genotyped for 10 genetic variants in different transporters' genes. Additionally, valsartan-treated volunteers were genotyped for 29 genetic variants in genes encoding for different metabolizing enzymes. Variability in pharmacokinetic parameters such as maximum concentration (Cmax) and time to reach it (tmax), the incidence of adverse drug reactions (ADRs) and blood pressure measurements were analyzed as a function of pharmacogenetic and demographic parameters. Individuals with the ABCB1 rs1045642 T/T genotype were associated with a higher valsartan tmax compared to those with T/G and G/G genotypes (p < 0.001, β = 0.821, R2 = 0.459) and with a tendency toward a higher postural dizziness incidence (11.8% vs. 0%, p = 0.070). A higher hydrochlorothiazide dose/weight (DW)-corrected area under the curve (AUC∞/DW) was observed in SLC22A1 rs34059508 G/A volunteers compared to G/G volunteers (p = 0.050, β = 1047.35, R2 = 0.051), and a tendency toward a higher postural dizziness incidence (50% vs. 1.6%, p = 0.063). Sex impacted valsartan and hydrochlorothiazide pharmacokinetics, showing a lower exposure in women, whereas no significant differences were found for olmesartan pharmacokinetics.

What do we know today about drug-induced microscopic colitis? A case of lymphocytic colitis on olmesartan

Microscopic colitis is part of the differential diagnosis of chronic watery diarrhea. Colonoscopy discloses a normal looking mucosa, therefore its diagnosis is based on histology of colonic biopsies. Two main phenotypes are distinguished: collagenous colitis and lymphocytic colitis. A third entity, incomplete microscopic colitis or unspecified microscopic colitis has been reported in the literature. It affects preferentially women over 60 years of age and its association with certain drugs is increasingly established. In case of suspected drug-induced microscopic colitis, identification of the responsible drug is a key to management. After discontinuation of the suspected drug, the gold standard of treatment is budesonide both for induction and for maintenance in case of clinical relapse, as is often the case after discontinuation. Therapy with immunomodulators, biologics, or surgery is reserved for refractory forms of microscopic colitis after multidisciplinary consultation. Through the clinical case of colitis on olmesartan, we will review the latest recommendations on drug-induced microscopic colitis.

A Rare Case of Olmesartan-Associated Enteropathy Successfully Managed With Steroid Taper

Olmesartan is a commonly used antihypertensive medication belonging to the class of angiotensin II receptor blockers. Though generally well-tolerated, olmesartan can rarely cause olmesartan-associated enteropathy (OAE) with non-bloody diarrhea, weight loss, abdominal pain, and vomiting. Patients may develop enteropathy months to years after drug initiation. In severe cases, patients may develop complications that require hospitalization. Diagnosis is often delayed due to unfamiliarity of OAE, nonspecific presenting symptoms, and normal-appearing gross endoscopic findings. Esophagogastroduodenoscopy (EGD) with biopsy is essential to the diagnosis, showing sprue-like enteropathy with intestinal villous atrophy and mucosal inflammation. This report describes a case of a 70-year-old man who presented with three months of profuse watery diarrhea and 40-pound unintentional weight loss. After an extensive workup, including EGD with duodenal biopsies, the patient was diagnosed with OAE. The biopsies showed findings consistent with acute and chronic duodenitis, mucosal desquamation and ulceration, blunting of villi, and a sprue-like pattern with neutrophils. Celiac serologies and anti-enterocyte antibodies were negative, further supporting the diagnosis of OAE. Complete resolution of symptoms was achieved by discontinuing olmesartan and administering a steroid taper. Considering the frequent use of olmesartan, the increasing occurrence of OAE, and the wide range of associated symptoms, it is crucial for providers to recognize OAE and consider early discontinuation of olmesartan. This approach can help prevent further intestinal damage, protracted symptoms, unnecessary diagnostic tests, and financial burdens on both patients and the healthcare system.

Exploring the Effectiveness and Safety of Azilsartan-Medoxomil/Chlorthalidone Versus Olmesartan-Medoxomil/Hydrochlorothiazide in Hypertensive Patients: A Meta-Analysis

This study aims to assess the effectiveness and safety of azilsartan-medoxomil/chlorthalidone (AZI-M/CT) compared to olmesartan-medoxomil/hydrochlorothiazide (OLM/HCTZ) in patients with hypertension. Systematic searches were conducted on PubMed, Google Scholar, and ClinicalTrials.gov, starting from their establishment until March 15, 2023. The purpose of these searches was to locate original reports that compare the effectiveness of AZI-M/CT and OLM/HCTZ in treating hypertension. Data on various characteristics at the beginning and end of the studies were gathered. The analyses were carried out using Review Manager 5.4.1 (The Nordic Cochrane Center, The Cochrane Collaboration, 2014, Odense, Denmark) and STATA 16.0 software (Stata Corp. LP, College Station, TX, USA). Risk ratios (RRs) and weighted mean differences (WMDs) with 95% confidence intervals (CIs) were calculated as part of the study. A total of 3,146 individuals from four separate investigations were included in the study, with 1,931 individuals receiving AZI-M/CT and 1,215 individuals receiving OLM/HCTZ. The combined analysis revealed that the average diastolic blood pressure (DBP) was significantly lower in the AZI-M/CT group compared to the OLM/HCTZ group (WMD -2.64 [-2.78, -2.51]; P = 0.00001; I² = 1%). However, there were no significant differences in mean systolic blood pressure (SBP; WMD -2.95 [-6.64, 0.73]; P = 0). Furthermore, the AZI-M/CT group had a notably higher incidence of major adverse events (RR 1.58 [1.20, 2.08]; P = 0.001; I² = 11%) and any treatment-emergent adverse events (RR 1.11 [1.03, 1.20]; P = 0.007; I² = 51%). However, there was no significant difference in the mortality risk between the two groups (RR 0.74 [0.14, 3.91]; P = 0.72; I² = 0%). Based on the results of our meta-analysis, AZI-M/CT is more effective than OLM/HCTZ at reducing blood pressure in elderly hypertensive patients. However, because of the small sample size, favorable results must be carefully reevaluated, and more studies are needed.

Olmesartan alleviates SARS-CoV-2 envelope protein induced renal fibrosis by regulating HMGB1 release and autophagic degradation of TGF-β1

Background and aims: Renal damage in severe coronavirus disease 2019 (COVID-19) is highly associated with mortality. Finding relevant therapeutic candidates that can alleviate it is crucial. Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin-receptor blockers (ARBs) have been shown to be harmless to COVID-19 patients, but it remains elusive whether ACEIs/ARBs have protective benefits to them. We wished to determine if ACEIs/ARBs had a protective effect on the renal damage associated with COVID-19, and to investigate the mechanism. Methods: We used the envelope (E) protein of severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) to induce COVID-19-like multiple organ damage and observed renal fibrosis. We induced the epithelial-mesenchymal transformation of HK-2 cells with E protein, and found that olmesartan could alleviate it significantly. The protective effects of olmesartan on E protein-induced renal fibrosis were evaluated by renal-function assessment, pathologic alterations, inflammation, and the TGF-β1/Smad2/3 signaling pathway. The distribution of high-mobility group box (HMGB)1 was examined after stimulation with E protein and olmesartan administration. Results: E protein stimulated HMGB1 release, which triggered the immune response and promoted activation of TGF-β1/Smad2/3 signaling: both could lead to renal fibrosis. Olmesartan regulated the distribution of HMGB1 under E protein stimulation. Olmesartan inhibited the release of HMGB1, and reduced the inflammatory response and activation of TGF-β1/Smad2/3 signaling. Olmesartan increased the cytoplasmic level of HMGB1 to promote the autophagic degradation of TGF-β1, thereby alleviating fibrosis further. Conclusion: Olmesartan alleviates E protein-induced renal fibrosis by regulating the release of HMGB1 and its mediated autophagic degradation of TGF-β1.

Twenty-Four-Hour Blood Pressure-Lowering Efficacy of Sacubitril/Valsartan Versus Olmesartan in Japanese Patients With Essential Hypertension Based on Nocturnal Blood Pressure Dipping Status: A Post Hoc Analysis of Data From a Randomized, Double-Blind Multicenter Study

Background Nighttime blood pressure (BP) and an abnormal nocturnal BP dipping profile are important cardiovascular risk factors in patients with hypertension. This post hoc analysis investigated the effects of sacubitril/valsartan on 24-hour BP in patients with mild-to-moderate hypertension and in patient subgroups based on nocturnal BP dipping status. Methods and Results Data from a randomized clinical trial comparing the BP-lowering effects of 8 weeks of treatment with sacubitril/valsartan (200 or 400 mg/d) and olmesartan (20 mg/d) in Japanese patients with mild-to-moderate hypertension were analyzed. The primary end point was change in 24-hour, daytime, and nighttime BP in patient subgroups based on nocturnal BP dipping status (dipper, nondipper). Six hundred thirty-two patients with baseline and follow-up ambulatory BP data were included. Both sacubitril/valsartan dosages reduced 24-hour, daytime, and nighttime systolic BP, and 24-hour and daytime diastolic BP, to a significantly greater extent than olmesartan in the dipper and nondipper groups. However, between-group differences in nighttime systolic BP were more significant in the nondipper group (difference [95% CI] for sacubitril/valsartan 200 and 400 mg/d versus olmesartan 20 mg/d: -4.6 [95% CI, -7.3 to -1.8] and -6.8 [95% CI, -9.5 to -4.1] mm Hg, respectively; P<0.01 and P<0.001). Between-group differences in the BP control rate were greatest in the nondipper subgroup (systolic BP control rate of 34.4% and 42.6% with sacubitril/valsartan 200 and 400 mg/d versus 23.1% with olmesartan 20 mg/d). Conclusions This analysis highlights the value of sacubitril/valsartan therapy in patients with a nondipper profile of nocturnal BP and confirms this agent's potent 24-hour BP-lowering effect in Japanese populations with hypertension. Registration URL: https://www.clinicaltrials.gov; Unique identifier: NCT01599104.

Olmesartan-Induced Ischemic Enteritis Complicated With Bowel Perforation: A Case Report and Literature Review

Olmesartan is a relatively new angiotensin receptor blocker used widely to control hypertension. Cases have been reported previously of enteropathy induced by olmesartan. Here, the authors report a case of olmesartan-induced ischemic enteritis complicated by bowel perforation. A 52-year-old male patient, during the treatment with olmesartan, developed severe abdominal pain of five-day duration. He underwent exploratory laparotomy for bowel perforation and surgical resection of the ischemic bowel segment. On a two-month follow-up after the discontinuation of olmesartan and the emergency surgery, the patient was symptom-free and functioning well. This rare report focuses on ischemic enteritis associated with olmesartan, describes the symptoms, and records the progression of this side effect and the corresponding treatment. Our case aims to raise awareness amongst physicians about the possibility of this severe complication and to point out that more research is still needed on its pathophysiology to better understand this drug.

The histological spectrum of ARB-induced gastritis

AIMS

Olmesartan, an angiotensin receptor blocker (ARB) used for hypertension management, is known to cause a sprue-like enteropathy in a subset of patients. Rare cases of gastritis occurring with ARB use have also been reported, but the histological features of ARB-induced gastritis and the response to drug cessation have not been examined in a dedicated case-series.

METHODS AND RESULTS

Cases of suspected ARB-induced gastritis were identified from the pathology archives of four institutions. Haematoxylin and eosin (H&E) slides from gastric biopsies were reviewed. Fifteen patients (14 female, one male) were identified. The most common presenting symptoms were diarrhoea (10) and weight loss (six). Gastric biopsies commonly showed a full-thickness active chronic gastritis with surface epithelial injury involving the antrum and body. Glandular atrophy, intra-epithelial lymphocytosis and/or subepithelial collagen thickening were also present in some cases. Duodenal involvement, including villous atrophy, intra-epithelial lymphocytosis and/or collagenous sprue, was identified in 11 of 13 cases with concurrent duodenal biopsies. Following drug cessation, symptomatic improvement occurred in all 11 cases for which follow-up data were available. Histological resolution occurred in five of eight cases with follow-up gastric biopsies, with improvement seen in the remaining three biopsies.

CONCLUSION

ARB-induced gastritis typically presents as active chronic gastritis, frequently with associated surface epithelial injury. Glandular atrophy, intra-epithelial lymphocytosis and/or subepithelial collagen thickening may also be present. These gastric changes can be seen without associated duodenal injury in rare cases, and they should alert the pathologist to the possibility of ARB-induced injury. Drug cessation results in marked symptomatic and histological improvement.

Pharmacokinetics and Bioequivalence Evaluation of 2 Olmesartan Medoxomil and Amlodipine Besylate Fixed-Dose Combination Tablets in Healthy Chinese Volunteers Under Fasting and Fed Conditions

Combined antihypertensive drugs have become the basic method of treating hypertension. Olmesartan and amlodipine, as representative drugs of angiotensin receptor blockers and calcium channel blockers, were developed as a compound formulation for antihypertensive treatment. The purpose of this study was to evaluate the bioequivalence of olmesartan medoxomil/amlodipine besylate tablet (20 mg/5 mg) under fasting and fed conditions in healthy Chinese volunteers. A phase 1 randomized, open-label, 2-period, single-dose crossover study (n = 56) was designed, with subjects under fasting (n = 28) or fed (n = 28) conditions. Of the 56 enrolled participants, 55 healthy volunteers completed the study. Blood samples for pharmacokinetic analysis were collected from 1.5 hours before dosing to 168 hours after dosing. The 90%CIs for the geometric mean ratios of maximum plasma drug concentration, area under the plasma concentration-time curve (AUC) from time 0 to the last measurable concentration and AUC from time 0 to infinity of the test/reference were all within the acceptance range for bioequivalence (80%-125%). The data showed that the absorption of amlodipine is not affected by food, but the exposure of olmesartan (both AUC from time 0 to the last measurable concentration and AUC from time 0 to infinity were P < .05) reduced significantly after consuming a high-fat meal, which indicates that the effects of food on olmesartan exposure in healthy Chinese were clinically relevant. During the study, there were no suspected serious adverse reactions or serious adverse events. All adverse events were determined to be mild after Common Terminology Criteria for Adverse Events 5.0 evaluation. These results indicated that both the test and reference formulations were bioequivalent with similar safety profiles.

A Prospective Randomized, Double-Blind, Multi-Center, Phase III Clinical Trial Evaluating the Efficacy and Safety of Olmesartan/Amlodipine plus Rosuvastatin Combination Treatment in Patients with Concomitant Hypertension and Dyslipidemia: A LEISURE Study

BACKGROUND

This study was a multicenter, randomized, double-blinded, placebo-controlled phase III clinical trial to investigate the efficacy and safety of an olmesartan/amlodipine single pill plus rosuvastatin combination treatment for patients with concomitant hypertension and dyslipidemia.

METHODS

Patients with both hypertension and dyslipidemia aged 20-80 were enrolled from 36 tertiary hospitals in Korea from January 2017 to April 2018. Patients were randomized to three groups in a 1:1:0.5 ratio, olmesartan/amlodipine single pill plus rosuvastatin (olme/amlo/rosu) or olmesartan plus rosuvastatin (olme/rosu) or olmesartan/amlodipine single pill (olme/amlo) combination. The primary endpoints were change of sitting systolic blood pressure (sitSBP) from baseline in the olme/amlo/rosu vs. olme/rosu groups and the percentage change of low-density lipoprotein cholesterol (LDL-C) from baseline in the olme/amlo/rosu vs. olme/amlo groups after 8 weeks of treatment.

RESULTS

A total of 265 patients were randomized, 106 to olme/amlo/rosu, 106 to olme/rosu and 53 to olme/amlo groups. Baseline characteristics among the three groups did not differ. The mean sitSBP change was significantly larger in the olme/amlo/rosu group with -24.30 ± 12.62 mmHg (from 153.58 ± 10.90 to 129.28 ± 13.58) as compared to the olme/rosu group, -9.72 ± 16.27 mmHg (from 153.71 ± 11.10 to 144.00 ± 18.44 mmHg). The difference in change of sitSBP between the two groups was -14.62± 1.98 mmHg with significance (95% CI -18.51 to -10.73, p < 0.0001). The mean LDL-C reduced significantly in the olme/amlo/rosu group, -52.31 ± 16.63% (from 154.52 ± 30.84 to 72.72 ± 26.08 mg/dL) as compared to the olme/amlo group with no change, -2.98 ± 16.16% (from 160.42 ± 32.05 to 153.81 ± 31.57 mg/dL). Significant difference in change was found in LDL-C between the two groups with -50.10 ± 2.73% (95% CI -55.49 to -44.71, p < 0.0001). Total adverse drug reaction rates were 10.48%, 5.66% and 3.7% in the olme/amlo/rosu, olme/rosu and olme/amlo groups, respectively with no statistical significance among the three groups. Serious adverse drug reactions did not occur.

CONCLUSIONS

Olmesartan/amlodipine single pill plus rosuvastatin combination treatment for patients with both hypertension and dyslipidemia is effective and safe as compared to either olmesartan plus rosuvastatin or olmesartan plus amlodipine treatment.

[Olmesartan-associated Enteropathy]

Olmesartan,an angiotensin Ⅱ receptor blocker,is a commonly used antihypertensive drug.Several case reports and cohort studies in recent years have described a severe gastrointestinal adverse event with chronic diarrhea,intestinal malabsorption,and weight loss after the administration of olmesartan.In such cases,the patients recovered after discontinuing olmesartan.This adverse effect is called olmesartan-associated enteropathy(OAE).This article reviews the potential pathogenesis and clinical characteristics of OAE,which broadens the disease spectrum for the differential diagnosis of chronic diarrhea and intestinal malabsorption.

Diarrhea and angiotensin II receptor blockers: Is there any difference between the different drugs?

Diarrhea is an adverse drug reaction (ADR) widely reported with olmesartan, an angiotensin II receptor blocker (ARB). Isolated case reports described this ADR with other ARBs. The present study was performed to investigate if, among the different ARBs, some drugs are more at risk of diarrhea than others. Using VigiBase®, the WHO pharmacovigilance database, we performed a disproportionality analysis (case/noncase study). Cases were reports with the MedDRA PT term « diarrhea » and noncases all other reports registered during the same period in Vigibase® from April 6, 1995 to December 31, 2020. After comparison of ARBs and angiotensin converting enzyme inhibitors (ACEIs), the main analysis was a comparison of the diarrhea reporting risk between each ARB and the seven other ARBs. Results are reported as reporting odds ratio (ROR) adjusted on age, gender, exposure to antihypertensive, and antidiabetic drugs with their 95% confidence interval. Among the 22,429,334 deduplicated reports registered in VigiBase® during the study period, 73,507 involved ARBs, including 2119 diarrhea. The reporting risk of diarrhea was higher with ARBs than with ACEIs (ROR = 2.06 (1.55-2.17)). Diarrhea with ARBs mainly occurred in females with a mean age of 65 years. After exclusion of olmesartan (to minimize a notoriety bias), two ARBs were significantly associated with diarrhea: eprosartan (ROR = 1.93 (1.32-2.72) and telmisartan (ROR = 1.41 (1.23-1.62) but not the six others. The present study found first that diarrhea is more frequently reported with ARBs than with ACEIs and second that the risk of diarrhea differs according to the different ARBs. Diarrhea with ARBs is not a class effect.

Olmesartan-Induced Enteropathy: A Report of an Unusual Cause of Chronic Diarrhea

Olmesartan, an angiotensin II receptor blocker indicated in the treatment of hypertension, has been associ­ated with a seronegative sprue-like enteropathy that should be considered in the differential diagnosis of patients with unexplained chronic diarrhoea. It typically presents with severe chronic diarrhoea, considerable weight loss, and villous atrophy on biopsy and may be difficult to recognize because of its clinical and histological similarities to other clinical entities. Practically, discontinuation of the drug leads to dramatic recovery of the symptoms. We report a 76-year-old Caucasian female who was admitted to our hospital with complaints of chronic diarrhea and significant weight loss. Medical history was notable for hypertension being treated with olmesartan. Initially, investigation for all potential infectious causes and celiac disease was negative. Both upper and lower endoscopy was performed with duodenal biopsies revealing total villous atrophy and colonic biopsies showing lymphocytic colitis. In the presence of negative serology for celiac disease and after a thorough review of the patient’s medications, olmesartan in­duced-enteropathy was the most possible diagnosis. Olmesartan was discontinued and the symptoms rapidly resolved. A follow-up done a few months later showed no recurrence of the symptoms. In olmesartan-associated enteropathy, discontinuation of olmesartan results in immediate clinical recovery. Although rare, it is considered an emerging and underdiagnosed enteropathy. This case report illustrates the need for a thorough medication history evaluation and regular review during workup. We aim to increase the awareness of olmesartan-induced enteropathy among clinicians and gastroenterologists. We hope it will add to the current literature and help to understand this rare phenomenon in order to avoid unnecessary testing.

Sprue-Like Enteropathy and Liver Injury: A Rare Emerging Association with Olmesartan

Olmesartan-induced enteropathy is an underreported phenomenon, first described in 2012. While olmesartan's antihypertensive properties were confirmed early on, its association with a sprue-like enteropathy was subsequently noted. Although this association has been reported with olmesartan, there have been few reports of this association with other angiotensin-receptor blockers. We present a case of a 79-year-old male who presented with diarrhea, weight loss, jaundice, and transaminitis. Further history revealed that he had been taking olmesartan 40 mg daily for hypertension. Workup of his diarrhea and jaundice included duodenal and liver biopsies revealed findings consistent with a sprue-like enteropathy and an autoimmune hepatitis-like pattern. On discontinuation of olmesartan, his 1-month follow-up revealed significant improvement in his clinical status as well as his liver function tests. Olmesartan is an effective antihypertensive medication; however, physicians must be mindful of its side effect of causing a sprue-like enteropathy and liver injury. Patients should be counseled on discontinuing olmesartan, and they should be started on an alternative therapy for hypertension.

Olmesartan-associated duodenal villous atrophy, an emerging clinical issue

Duodenal villous atrophy with olmesartan was described in 2012, 10 years following registration of olmesartan. Clinical features are severe watery diarrhoea, usually occurring in association with weight loss. Onset is delayed, with a mean duration of prior exposure to olmesartan of 3 years. Diagnosis may be delayed. Symptoms resolve over weeks following cessation of olmesartan. Epidemiological studies suggest increased risk with olmesartan, rather than a class effect of all angiotensin receptor blockers. Post-marketing surveillance for drug safety remains important.

Role of the renin-angiotensin system in the development of cataract formation in angiotensin-II-induced experimental rats

Previously, we established several facts regarding hypertension-associated cataractogenesis. As a follow-on study, we evaluated the role of the renin-angiotensin system (RAS) in angiotensin-II (Ang-II)-induced cataract formation in experimental hypertensive rats. Sprague-Dawley male albino rats (150-180 g) were used for the present experiment. The animals were divided into four groups, with six animals in each group. During the 12 weeks of the experimental protocol, the normal group received sterile water (1 ml/kg/day, subcutaneously (sc), and the Ang-II control group received angiotensin (1 mg/kg/day) subcutaneously. The ARB (O) group received olmesartan (2 mg/kg/day) orally, and the ARB (T) group received two drops of olmesartan (5 mM) topically on the cornea; concurrently, both groups were treated with Ang-II (1 mg/kg/day, sc) to induce hypertension. Biweekly, the systolic and the diastolic blood pressures were recorded, and the eyes were examined; moreover, cataractogenic parameters, such as oxidative stress markers and protein contents in the lenses, were evaluated after completion of the experimental protocol. Twelve weeks of olmesartan administered, orally or topically, significantly reduced the progression of cataract formation and restored antioxidants, lipid peroxidation, nitrite content, and protein contents in the lenses of the mice in groups O and T, respectively, as compared with those in the Ang-II control group. On the basis of our results, we conclude that the ocular RAS exacerbates the lenticular oxidative stress that may lead to cataract formation. The results showed that the RAS has an independent and important role in cataract formation under hypertensive conditions.

Effect of Early Normotension with Olmesartan on Rho-kinase Activity in Hypertensive Patients

BACKGROUND

Angiotensin II is a potent activator of the Rho-kinase (ROCK) pathway, through which it exerts some of its adverse vasoconstrictor effects. Clinical evidence on the effects of blocking the angiotensin II receptor 1 on ROCK activity in hypertensive patients is scarce.

OBJECTIVE

To demonstrate that ROCK activity in peripheral blood mononuclear cells (PMBCs) in patients with essential hypertension is reduced earlier than previously observed, along with blood pressure (BP) lowering on treatment with olmesartan.

METHODS

Prospective pilot open study; 17 hypertensive patients were treated with progressive olmesartan doses starting with 20 mg qd. BP was measured at 3, 6 and 9 weeks after treatment initiation. If treatment failed to normalize BP after 3 weeks, olmesartan dose was increased to 40 mg qd, and if still hypertensive after 6 weeks, 12.5 mg of hydrochlorothiazide qd was added. ROCK activity was measured at baseline and 9 weeks after treatment as myosin phosphatase target subunit 1 phosphorylation (MYPT1-p/T ratio) in PBMC.

RESULTS

Mean baseline BP was 162 ± 4.9/101 ± 2.4 mmHg. After 9 weeks of treatment, both systolic and diastolic BP were reduced by 41 and 22 mmHg, respectively (p<0.05). Mean pretreatment MYPT1- p/T ratio in PMBCs was significantly reduced by 80% after 9 weeks with olmesartan (p<0.01).

CONCLUSION

Normotension achieved after 9 weeks in 82% of the patients treated with olmesartan was associated with a significant reduction of ROCK activity in PBMC.

[Olmesartan inhibits age-associated migration and invasion of human aortic vascular smooth muscle cells by upregulating miR-3133 axis]

OBJECTIVE

To explore the effects of olmesartan on age-associated migration and invasion capacities and microRNA (miRAN) axis in human aortic vascular smooth muscle cells (HA-VSMCs).

METHODS

Cultured HA-VSMCs were divided into control group, bleomycin-mediated senescence (BLM) group and bleomycin + olmesartan treatment group. Wound-healing assay and Boyden chambers invasion assay were used to assess the changes in migration and invasion of the cells, gelatin zymography was used to analyze matrix metalloproteinase-2 (MMP-2) activation in the cells. The differentially expressed miRNAs were identified by miRNA microarray assay and validated by quantitative real-time PCR. MiR-3133 inhibitor was used to examine the effects of molecular manipulation of olmesartan on age-associated migration and invasion and MMP-2 activation in the cells.

RESULTS

Compared with those of the control group, the percentage of the repopulated cells and the number of cells crossing the basement membrane increased significantly in BLM group [(78.43±12.76)% vs (42.47±7.22)%, P &lt; 0.05; 33.33±5.51 vs 13.00±4.36, P &lt; 0.05]. A significant increase of MMP-2 activation was found in BLM group as compared with the control group (1.66 ± 0.27 vs 0.87 ± 0.13, P &lt; 0.05). Olmesartan significantly inhibited BLM-induced enhancement of cell migration and invasion and MMP-2 secretion in the cells. MiR-3133 was significantly downregulated in BLM group and upregulated in olmesartan group. Transfection with miR-3133 inhibitor significantly reversed the effects of olmesartan on age-associated migration and invasion of the cells [(85.87±7.39)% vs (49.77±3.05)%; 34.67±2.31 vs 20.00±4.58, P &lt; 0.05] and MMP-2 activation in the cells (1.76±0.19 vs 0.94±0.10, P &lt; 0.05).

CONCLUSIONS

Olmesartan inhibits the migration and invasion of ageassociated HA-VSMCs probably by upregulating of the miR-3133 axis.

[Impact of stopping reimbursement of olmesartan for hypertensive patients in primary care]

AIMS OF STUDY

Since January 2017, olmesartan-based treatment are no longer reimbursed by French national health insurance. Indeed, enteropathy cases, potentially lethal, were described in relation to this medication. Objectives were to study the impact of stopping the reimbursement of olmesartan for hypertensive patients.

PATIENTS AND METHOD

A descriptive retrospective study was performed with data from two primary care facilities in French occidental Normandy. To evaluate the blood pressure control, different blood pressure measurements were considered during the year before (period 1) and the year after (period 2) potential stopping olmesartan. A medico-economic analysis was also realized.

RESULTS

From June 2015 to July 2017, 107 hypertensive patients treated by olmesartan were included. Among them, 47 patients (44%) had an antihypertensive monotherapy. olmesartan had been mainly switched by another sartan (75%, 80/107) including valsartan (59%, 47/80). Mean blood pressures during period 1 and period 2 were not statistically different. Moreover, 83% of patients were initially controlled with olmesartan and 81% after switching medication (P=0,86). The use of olmesartan generated an additional cost of 58% compared to the other drugs that replaced it during period 2.

CONCLUSIONS

Stopping olmesartan reimbursement didn't seem to have a significant impact on blood pressure control of hypertensive patients while its cost is significant. In addition to potential serious side effects, olmesartan has not shown any improvement in cardiovascular morbi-mortality.

Olmesartan alleviates bleomycin-mediated vascular smooth muscle cell senescence via the miR-665/SDC1 axis

Olmesartan (OMST) is a new angiotensin II receptor antagonist recently approved by the FDA to treat cardiovascular diseases. We investigated the molecular mechanisms by which OMST regulates vascular senescence. In the present study, bleomycin (BLM) was used to induce senescence in vascular smooth muscle cells (VSMCs); after which, the cells were treated with OMST. The effects of OMST on BLM-mediated cell senescence were evaluated using cell adhesion, NAD⁺/NADH, and Annevin V/PI double staining assays, as well as by immunofluorescence staining of γH2AX, Edu flow cytometry, and evaluations of senescence-associated β-gal activity. Differentially expressed microRNAs (DEMs) were identified by miRNA microarray assays, and subsequently validated by quantitative real time PCR. Bisulfite sequencing PCR (BSP) was used to detect the methylation status of the miR-665 promoter. The target genes of miR-665 were predicted and confirmed using luciferase reporter assays. We found that miR-665 was upregulated in VSMCs in response to BLM-induced cellular senescence. BSP studies revealed that CpG sites in the promoter region of the miR-665 gene underwent extensive demethylation during BLM-induced cellular senescence, and there was a concomitant up-regulation of miR-665 expression. SDC1 mRNA was identified as a direct target of miR-665. Either miR-665 overexpression or SDC1 knockdown significantly reversed the effects of OMST on BLM-induced VSMC senescence. Moreover, SDC1 overexpression partially reversed the changes that occurred in cells with BLM-induced senescence caused by miR-665 overexpression. Our findings suggest that the miR-665/SDC1 axis functions as a vital modulator of VSMC senescence, and may represent a novel biological target for treating atherosclerosis.

Olmesartan-induced Enteropathy: A Rare Side Effect of a Common Medication

Ischemic heart disease and stroke are the leading causes of mortality worldwide according to the World Health Organization. Hypertension is a major factor in the development of these diseases. Olmesartan is an angiotensin II receptor blocker (ARB) indicated in the treatment of hypertension. There are several case reports describing sprue-like enteropathy caused by olmesartan. We report on a 72-year-old patient referred to our hospital for work-up of chronic diarrhoea, vomiting and weight-loss, and villous atrophy on intestinal biopsy. The patient’s symptoms abated upon cessation of olmesartan. This case illustrates the need for a thorough medication history and regular review during work-up. We hope it will add to the current understanding of this rare phenomenon. 

Chronological Delivery of Antihypertensive Drugs in Bilayered Core-in-Cup Buccoadhesive Tablets: In Vitro and In Vivo Evaluation

Hypertension shows circadian blood pressure rhythms (day-night pattern) that urge the delivery of antihypertensive drugs at the right time in the desired levels. Thus, a bilayered core-in-cup buccoadhesive tablet was formulated that immediately releases olmesartan, to give a burst effect, and controls azelnidipine release, to prolong its therapeutic effect. The main challenge was the poor bioavailability of azelnidipine due to its poor aqueous solubility and first-pass effect. Hence, liquisolid compact buccoadhesive tablets were prepared to enhance solubility, dissolution profiles, and bypass the oral route. Two factorial designs were conducted to study the type and concentration effect of the mucoadhesive polymers on the dissolution and mucoadhesion of olmesartan and azelnidipine. Characterization studies were conducted regarding drug content, surface pH, water uptake, mucoadhesive strength, in vitro release, and ex vivo permeability. The core-in-cup olmesartan/azelnidipine buccoadhesive tablet showed similar release profile to the statistically optimized formulae of each drug. In vitro dissolution study showed enhanced release of azelnidipine than the directly compressed tablets, to comply with the regulatory standards of controlled release systems. In vivo pharmacokinetic study of olmesartan and azelnidipine conducted on human volunteers against Rezaltas® 10/8 mg tablet showed percentage relative bioavailability of 106.12 and 470.82%, respectively. Graphical Abstract.

Protective effects of olmesartan and l-carnitine on doxorubicin-induced cardiotoxicity in rats

Doxorubicin (DOX), an anthracycline antibiotic, is an important antineoplastic agent due to its high antitumor efficacy in hematological as well as in solid malignancies. The clinical use of DOX is limited due to its cardiotoxic effects. The present study aimed to investigate the possible protective effect of olmesartan (Olm), l-carnitine (L-CA), and their combination in cardiotoxicity induced by DOX in rats. Male albino rats were randomly divided into seven experimental groups (n = 8): group I: normal control, group II: L-CA, group III: Olm, group IV: DOX. The other three groups were treated with Olm (10 mg/kg), L-CA (300 mg/kg), and their combination for 2 weeks after induction of cardiotoxicity by a single dose of DOX (20 mg/kg). In the results, DOX showed a significant elevation in serum troponin I, creatine kinase-MB (CK-MB), and lactate dehydrogenase (LDH) together with increased inflammation manifested by the rise of tumor necrosis factor-alpha (TNF-α), intercellular adhesion molecules-1 (ICAM-1), interleukin IL-1β (IL-1β), myeloperoxidase (MPO), nuclear factor-kappa B (NF-κB), and transforming growth factor beta (TGF-β) in cardiac tissues as well as DOX-induced oxidative stress by increasing in malondialdehyde (MDA) and decreasing in superoxide dismutase (SOD) and glutathione (GSH) in heart tissues. In addition, caspase-3 activity was boosted as indication of increased apoptosis. On the other hand, administration of L-CA and Olm attenuated the DOX-evoked disturbances in the abovementioned parameters. In addition, DOX exhibited echocardiographic changes and severe histopathological changes, which were significantly reversed by L-CA and Olm treatment. In conclusion, the present study data confirm the protective role of L-CA and Olm in DOX-induced cardiotoxicity, which may be related to its antioxidant, antiinflammatory, and antiapoptotic agents.

Method Validation for Simultaneous Quantification of Olmesartan and Hydrochlorothiazide in Human Plasma Using LC-MS/MS and Its Application Through Bioequivalence Study in Healthy Volunteers

A new, simple, sensitive, selective, rapid, and high-throughput liquid chromatography-tandem mass spectrometry (LC-MS/MS) method has been developed and validated for simultaneous quantification of Olmesartan and hydrochlorothiazide in human plasma. Simple liquid–liquid extraction procedure was applied for plasma sample pretreatment using a mixture of diethyl ether and dichloromethane, as an extraction solution. Analytes were separated on UNISOL C18 150*4.6 mm, 5 µm column using methanol, and 2 mM ammonium acetate pH 5.5 (80:20, v/v) as a mobile phase and detected by electrospray ionization in the multiple reaction monitoring (MRM) mode. The mass transition ion pairs were followed in negative ion mode as m/z 445.20 → 148.90 for Olmesartan; m/z 451.40 → 154.30 for Olmesartan D₆ and m/z 295.80 → 205.10 for hydrochlorothiazide; m/z 298.90 → 206.30 for hydrochlorothiazide ¹³C D₂. The method showed excellent linearity (r² > 0.99) over the concentration range of 5.002–2,599.934 ng/ml for Olmesartan and from 3.005 to 499.994 ng/ml for hydrochlorothiazide. Precision (% CV) and accuracy (% bias) for Olmesartan were found in the range of 3.07–9.02% and −5.00–0.00%, respectively. Precision (% CV) and accuracy (% bias) for hydrochlorothiazide were found in the range of 3.32–8.21% and 1.99–3.80%, respectively. This as developed novel and high-throughput liquid–liquid extraction bioanalytical method has substantial innovative value with the benefits of cost effectiveness, good extraction efficiency, shorter analysis run time, low organic solvent consumption, and simpler procedure over the previously reported solid-phase extraction method. The application of this method in pharmacokinetic studies was further demonstrated successfully through a bioequivalence study conducted on healthy human subjects, following oral administration of combined formulation of Olmesartan medoxomil and hydrochlorothiazide in fixed-dose tablet.

Olmesartan Attenuates Kidney Fibrosis in a Murine Model of Alport Syndrome by Suppressing Tubular Expression of TGFβ

Despite the wide use of angiotensin II receptor blockers in the treatment of Alport syndrome (AS), the mechanism as to how angiotensin II receptor blockers prevent interstitial fibrosis remains unclear. Here, we report that treatment of olmesartan effectively targets the feedback loop between the renin–angiotensin system (RAS) and transforming growth factor β (TGFβ) signals in tubular epithelial cells and preserves renal angiotensin-converting enzyme 2 (ACE2) expression in the kidney of Col4a3^–/– mice, a murine model of experimental AS. Morphology analyses revealed amelioration of kidney fibrosis in Col4a3^–/– mice by olmesartan treatment. Upregulation of TGFβ and activation of its downstream in Col4a3^–/– mice were attenuated by olmesartan in Col4a3^–/– mice. Intriguingly, TGFβ expression was preferentially upregulated in damaged tubular epithelial cells in Col4a3^–/– mice. Concurrent upregulation of TNFα-converting enzyme and downregulation of ACE2 suggested RAS activation in Col4a3^–/– mice, which was prevented by olmesartan. Mechanistically, olmesartan suppressed TGFβ-induced RAS activation in tubular epithelial cells in vitro. Collectively, we concluded that olmesartan effectively suppresses the progression of tubulointerstitial fibrosis in AS by interrupting RAS-TGFβ feedback loop to counterbalance intrarenal RAS activation.

Angiotensin II receptor blockers and gastrointestinal adverse events of resembling sprue-like enteropathy: a systematic review

Background

Olmesartan, an angiotensin II receptor blocker (ARB), is associated with gastrointestinal symptoms resembling sprue-like enteropathy. Some have proposed that enteropathy may be a class effect rather than olmesartan-specific. We performed a systematic review to identify literature of sprue-like enteropathy for all ARBs.

Methods

Case reports, case series and comparative studies of ARBs were searched on PubMed and Embase databases through 21 November 2018 and then assessed.

Results

A total of 82 case reports and case series as well as 5 comparative studies, including 248 cases, were selected and analysed. The ARBs listed in the case reports were olmesartan (233 users; 94.0%), telmisartan (5 users; 2.0%), irbesartan (4 users; 1.6%), valsartan (3 users; 1.2%), losartan (2 users; 0.8%) and eprosartan (1 user; 0.4%). The periods between ARB initiation and onset of symptoms ranged from 2 weeks to 13 years. Histologic results were reported in 218 cases, in which 201 cases (92.2%) were villous atrophy and 131 cases (60.1%) were intraepithelial lymphocytosis. Human leucocyte antigen (HLA) testing was performed in 147 patients, among whom 105 (71.4%) had HLA-DQ2 or HLA-DQ8 haplotypes. Celiac-associated antibodies were tested in 169 patients, among whom 167 (98.8%) showed negative results. Gluten exclusion from the diet failed to relieve symptoms of enteropathy in 127 (97.7%) of 130 patients with information. Complete remission of symptoms after discontinuation of ARB was reported in 233 (97.4%) of the 239 patients with information. Seven cases (2.8%) reported recurrence of symptoms after restarting olmesartan; rechallenge was not reported for the non-olmesartan ARBs. The retrospective studies conducted worldwide had inconsistent study designs (e.g. differences in periods of study and case definition) and findings.

Conclusions

Although enteropathy is rare, clinicians should remain vigilant of this potential adverse event even years after medication initiation.

Pharmacokinetic comparison of a fixed-dose combination versus concomitant administration of amlodipine, olmesartan, and rosuvastatin in healthy adult subjects

Objective: The aim of this study was to compare the pharmacokinetic (PK) and safety profiles of a fixed dose combination (FDC) formulation and co-administration of amlodipine, olmesartan, and rosuvastatin. Materials and methods: This study was an open-label, randomized, cross-over design conducted in healthy male volunteers. All subjects received either a single FDC tablet containing amlodipine 10 mg/olmesartan 40 mg/rosuvastatin 20 mg, or were co-administered an FDC tablet containing amlodipine 10 mg/olmesartan 40 mg and a tablet containing rosuvastatin 20 mg, for each period, with 14-day washout periods. Plasma concentrations of amlodipine, olmesartan, and rosuvastatin were measured by liquid chromatography tandem mass spectrometry. Safety was evaluated by measuring vital signs, clinical laboratory parameters, physical examinations, and medical interviews. Results: Sixty-four subjects were enrolled, and 54 completed the study. The geometric mean ratios and 90% CI for the maximum plasma concentration (C_max) and area under the curve from time zero to the last sampling time (AUC_t) were 1.0716 (1.0369,1.1074) and 1.0497 (1.0243,1.0757) for amlodipine, 1.0396 (0.9818,1.1009) and 1.0138 (0.9716,1.0578) for olmesartan, and 1.0257 (0.9433,1.1152) and 1.0043 (0.9453,1.0669) for rosuvastatin. Fourteen cases of adverse events occurred in 12 subjects. There was no statistically significant clinical difference between the formulation groups. Conclusion: The 90% CI of the primary PK parameters were within the acceptance bioequivalence criteria, which is ln (0.8) and ln (1.25). These results indicate that the FDC formulation and co-administration of amlodipine, olmesartan and rosuvastatin are pharmacokinetically bioequivalent and have similar safety profiles.

Management of arterial hypertension with angiotensin receptor blockers: Current evidence and the role of olmesartan

Elevated blood pressure (BP) is a major determinant of morbidity and mortality burden related to cardio‐metabolic risk. Current guidelines indicate that controlling and lowering BP promotes cardiovascular (CV) risk reduction. Among antihypertensive agents, angiotensin receptor blockers (ARBs) are characterized by an efficacy profile equivalent to other antihypertensive agents and are provided with excellent tolerability and low discontinuation rates during chronic treatments. Moreover, CV outcomes are reduced by ARBs. Olmesartan is a long‐lasting ARB which proved to achieve a comparable or more effective action in lowering BP when compared to other ARBs. Olmesartan, in fact, displayed a larger and more sustained antihypertensive effect over the 24 hours, with a buffering effect on short‐term BP variability. These are important features which differentiate olmesartan from the other principles of the same class and that may help to control the increased CV risk in the presence of high BP variability. Olmesartan shows similar benefits as other ARBs in terms of all‐cause and CV mortality, and a favorable tolerability profile. Combination of olmesartan with long‐lasting calcium‐channel blockers and thiazide diuretics represents a rational and effective therapy. Thus, ARBs, including olmesartan, represent one of the most effective and safe treatments for patients with arterial hypertension.

Plantar Psoriasis Associated with Olmesartan

BACKGROUND

Psoriasis is a chronic inflammatory skin disorder that may be initiated or exacerbated by some drug intakes. Some of the most common medications known to trigger or worsen existing psoriasis include lithium, gold salts, beta blockers and antimalarials.

CONCLUSION

We report an exceptional case of plantar psoriasis in a woman who was treated by olmesartan for 3 years.

Home blood pressure and cardiovascular outcomes in very elderly patients receiving antihypertensive drug therapy: a subgroup analysis of Home blood pressure measurement with Olmesartan Naive patients to Establish Standard Target blood pressure (HONEST) study

The appropriate target blood pressure (BP) in elderly patients with hypertension remains uncertain. We investigated the relationship between morning home systolic blood pressure (MHSBP) during follow-up and cardiovascular (CV) risk in outpatients receiving olmesartan-based treatment aged <75 years (n = 16799) and ≥75 years (n = 4792) in the HONEST study. In the follow-up period (mean 2.02 years), the risk for major CV events was significantly higher in patients with MHSBP ≥155 mmHg compared with <125 mmHg in both age groups in Cox proportional hazards model adjusted for other risk factors and there was no significant difference in trend between the two groups (interaction P = 0.9917 for MHSBP). Hazard ratios for CV events for 1-mmHg increase in MHSBP were similar in patients aged <75 years and in patients aged ≥75 years. The incidence of adverse drug reactions related to excessive BP lowering was lower in patients <75 years than in patients ≥75 years (0.73 vs 1.02%, P = 0.0461). In conclusion, the study suggests even in patients ≥75 years antihypertensive treatment targeting the same MHSBP levels in patients <75 years may be beneficial in reducing CV risk when treatment is tolerated.

Severe intestinal malabsorption associated with ACE inhibitor or angiotensin receptor blocker treatment. An observational cohort study in Germany and Italy

Purpose

The angiotensin II receptor blocker (ARB) olmesartan has been recently associated with sprue‐like enteropathy (SLE), a gastrointestinal condition characterized by intestinal malabsorption (IM) and severe diarrhea. Whether the increased risk of SLE is substance‐specific or a class effect involving all ARBs is uncertain. The aim of this study is to assess the risk of enteropathy associated with ARBs and angiotensin converting enzyme inhibitors (ACE‐i) by using data from large administrative and claim databases.

Methods

We obtained data from Italian local health‐care units and a large German claim database and included patients treated with olmesartan, other ARBs, and ACE‐i. In the absence of a specific diagnosis code for SLE, International Classification of Diseases codes for IM were used. Analysis implemented a Poisson regression with robust error variance procedure, which allowed accounting for different clusters (local health‐care units and countries) and correctly estimating the standard error for the relative risk of rare event occurrence.

Results

Patients were divided into 3 groups: olmesartan (25.591, 5.5%), other ARBs (104.901, 22.5%), and ACE‐i patients (334.951, 72.0%). Baseline characteristics were similar overall. The incidence of unspecified IM in ACE‐i patients was not different compared with that of olmesartan, whereas a higher rate ratio was observed when comparing ARB patients with the olmesartan group (RR: 2.50, 95% CI 1.21 to 5.19, P .01). When International Classification of Diseases codes for coeliac disease were included, no differences were observed.

Conclusions

We could not confirm previous findings of a higher risk of malabsorption in olmesartan‐only patients, and drug‐induced enteropathy should be considered the result of exposure to the class of ARBs rather than a specific drug‐related effect.

Efficacy and safety of sacubitril/valsartan in patients with essential hypertension uncontrolled by olmesartan: A randomized, double-blind, 8-week study

A majority of patients with hypertension fail to achieve blood pressure (BP) control despite treatment with commonly prescribed drugs. This randomized, double-blind phase III trial assessed the superiority of sacubitril/valsartan 200 mg (97/103 mg) to continued olmesartan 20 mg in reducing ambulatory systolic BP after 8-week treatment in patients with mild to moderate essential hypertension uncontrolled with olmesartan 20 mg alone. A total of 376 patients were randomized to receive either sacubitril/valsartan (n = 188) or olmesartan (n = 188). Superior reductions in 24-hour mean ambulatory systolic BP were observed in the sacubitril/valsartan group vs the olmesartan group (-4.3 mm Hg vs -1.1 mm Hg, P < .001). Reductions in 24-hour mean ambulatory diastolic BP and pulse pressure and office systolic BP and diastolic BP were significantly greater with sacubitril/valsartan vs olmesartan (P < .014). A greater proportion of patients achieved BP control with sacubitril/valsartan vs olmesartan. The overall incidence of adverse events was comparable between the groups. Compared with continued olmesartan, sacubitril/valsartan was more effective and generally safe in patients with hypertension uncontrolled with olmesartan 20 mg.

Olmesartan attenuates pressure-overload- or post-infarction-induced cardiac remodeling in mice

Either angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor 1 blocker (ARB) attenuates cardiac remodeling. However, the overall molecular modulation of the reversing remodeling process in response to the ACEI or ARB treatment is not yet well determined. In this study, we examined whether gene expressions are modulated by ACEI (temocapril), ARB (olmesartan) or both in a murine model with transverse aortic constriction (TAC) and confirm whether periostin is a target gene of olmesartan in mice with myocardial infarction (MI). We detected 109 genes that were significantly up-regulated in TAC mice and a majority of these were down-regulated in response to temocapril, olmesartan or their combination which significantly attenuated cardiac remodeling at one or four weeks. Real-time RT-PCR demonstrated that olmesartan, temocapril or their combination down-regulated the expression of periostin. In MI mice treated with olmesartan for 4 weeks, the left ventricular end-diastolic and systolic dimensions measured with echocardiography were lower, whereas maximum rate of rise and fall rate of LV pressure (±dp/dt max) were greater, and Azan-staining cardiac fibrotic area was smaller. Furthermore, periostin was upregulated in response to MI, whereas olmesartan blocked this upregulation. Post-MI fibrosis was smaller in periostin knockout adult mice than in wildtype mice, while glycogen synthase kinase 3β was increased and cyclin D1 was decreased in periostin knockout mice. These findings indicate that periostin is a target gene of ARB and olmesartan reverses cardiac remodeling at least partially through the downregulation of periostin.

Unspecified intestinal malabsorption in patients treated with angiotensin-converting enzyme inhibitors or angiotensin receptor blockers: a retrospective analysis in primary care settings

OBJECTIVE

To investigate the possible relationship between the use of Angiotensin II Receptor Blockers (ARBs) or Angiotensin-Converting-Enzyme Inhibitors (ACE-i) and unspecified intestinal malabsorption (IM) within the Italian and German real-life context.

RESEARCH DESIGN AND METHODS

a retrospective cohort of patients with a new unspecified IM diagnosis during the period 1 January 2010-31 December 2013 was extracted from Italian IMS Health Longitudinal Patient Database and German IMS Disease Analyzer. Only patients with at least one prescription of ARB or ACE-i medication during the 6 months preceding the IM diagnosis were included and then followed up for 12 months to assess treatment exposure.

RESULTS

After stratification by year and molecule, the proportion of patients experiencing an unspecified IM diagnosis on total patients receiving ARBs or ACE-i ranged from 0% to 0.14%, showing no relevant differences between molecules and no time trends.

CONCLUSIONS

this study indicates that ACE-i or ARBs were rarely associated to an unspecified IM diagnosis. No relevant difference between each specific ACE-i and ARB was highlighted.

An unusual cause of severe, persistent diarrhoea

We present two cases of patients with severe persistent diarrhoea, in whom duodenal biopsies revealed villous atrophy that could be attributed to the use of olmesartan. The differential diagnosis of villous atrophy without serological markers of celiac disease should include drugs as possible cause, with olmesartan as a recently discovered culprit. Gastroenterologist should be aware of this entity.

Bioequivalence Study of a New Fixed-dose Combination Tablet Containing S-Amlodipine Nicotinate and Olmesartan Medoxomil in Healthy Korean Male Subjects

PURPOSE

A fixed-dose combination (FDC) pill of amlodipine (relatively old calcium channel blocker as dihydropyridine) and olmesartan (relatively new angiotensin II receptor blocker) is used for hypertension that is not adequately controlled with a single-formulation drug. Because the FDC is a one-pill formulation, and amlodipine and olmesartan have different mechanisms of action, it is expected to improve patients' medication compliance and have an increased blood pressure-lowering efficacy. The purpose of this study was to assess the safety profile and the bioequivalence of two different FDC formulations [amlodipine besylate/olmesartan medoxomil 10/40 mg (reference product) and S-amlodipine nicotinate/olmesartan medoxomil 5/40 mg (test product)].

METHODS

A randomized, open-label, single-dose, 2-treatment, 2-way, and 2-period crossover study, including a 3-week washout period, was performed in 32 healthy Korean male volunteers. To analyze the concentration of S-amlodipine or olmesartan, plasma samples were collected up to 144 hours after the dose for S-amlodipine and 48 hours after the dose for olmesartan. Pharmacokinetic parameters, including the C_max and the area under the curve from time 0 to the last measurable concentration (AUC_0-last) for the time versus concentration plot, were calculated. Analysis of variance for bioequivalence was conducted using C_max and AUC_0-last converted to log scale, and the mean ratios and 90% CIs were determined. Safety data included analysis of adverse events (AEs), vital signs, physical examinations, clinical laboratory test, and 12-lead ECGs.

FINDINGS

Of the 32 enrolled participants, 29 healthy volunteers completed the study. For both S-amlodipine and olmesartan, the main pharmacokinetic parameters were all within the acceptable range for regulatory bioequivalence. The 90% CIs for the geometric mean ratios of C_max and AUC_0-last were 0.8766 to 0.9760 and 0.8288 to 0.9224, respectively, for S-amlodipine and 0.9097 to 1.1229 and 0.8904 to 1.0407, respectively, for olmesartan. Hypotension was the most frequent AE, and it was observed in 4 volunteers with the test product and 7 volunteers with the reference product. Both the test and reference formulations were well tolerated.

IMPLICATIONS

The present study demonstrates that the newly developed FDC product (test drug) and the conventional FDC product (reference drug) have comparable pharmacokinetic characteristics in healthy adult male volunteers. Both the test and reference products indicated good tolerance in this population, and no serious AEs were observed.

Brain Renin-Angiotensin System: Does It Exist?

Because of the presence of the blood-brain barrier, brain renin-angiotensin system activity should depend on local (pro)renin synthesis. Indeed, an intracellular form of renin has been described in the brain, but whether it displays angiotensin (Ang) I-generating activity (AGA) is unknown. Here, we quantified brain (pro)renin, before and after buffer perfusion of the brain, in wild-type mice, renin knockout mice, deoxycorticosterone acetate salt-treated mice, and Ang II-infused mice. Brain regions were homogenized and incubated with excess angiotensinogen to detect AGA, before and after prorenin activation, using a renin inhibitor to correct for nonrenin-mediated AGA. Renin-dependent AGA was readily detectable in brain regions, the highest AGA being present in brain stem (>thalamus=cerebellum=striatum=midbrain>hippocampus=cortex). Brain AGA increased marginally after prorenin activation, suggesting that brain prorenin is low. Buffer perfusion reduced AGA in all brain areas by >60%. Plasma renin (per mL) was 40× to 800× higher than brain renin (per gram). Renin was undetectable in plasma and brain of renin knockout mice. Deoxycorticosterone acetate salt and Ang II suppressed plasma renin and brain renin in parallel, without upregulating brain prorenin. Finally, Ang I was undetectable in brains of spontaneously hypertensive rats, while their brain/plasma Ang II concentration ratio decreased by 80% after Ang II type 1 receptor blockade. In conclusion, brain renin levels (per gram) correspond with the amount of renin present in 1 to 20 μL of plasma. Brain renin disappears after buffer perfusion and varies in association with plasma renin. This indicates that brain renin represents trapped plasma renin. Brain Ang II represents Ang II taken up from blood rather than locally synthesized Ang II.

Effect of Olmesartan on the Level of Oral Cancer Risk Factor PAI1

AIM

To study if the angiotensin receptor blocker olmesartan reduces levels of plasminogen activator inhibitor 1 (PAI1), a risk factor for oral cancer, in a mouse model and therefore whether it could be used in the treatment of this malignancy.

MATERIALS AND METHODS

Twelve transgenic PAI1 mice aged 16-20 weeks were divided in two groups each containing six animals. One group was given olmesartan every day for 30 days in drinking water in an amount corresponding to their weight, 0.005 mg/g, while the second group did not receive any medication (control group). Blood samples were obtained from animals of both groups, before and after one month of olmesartan administration and plasma PAI1 levels were measured using enzyme-linked immunosorbent assay.

RESULTS

In the olmesartan-treated group, a significant decrease of PAI1 level was found after 1 month of treatment (11.9±8.6 vs. 21.7±7.2 ng/ml, respectively; p=0.028). However, no statistically significant difference was observed in PAI1 levels between the olmesartan-treated and control groups after one month, (p=0.177).

CONCLUSION

Olmesartan did not significantly affect PAI1 levels in this mouse model.

Small bowel enteropathy associated with olmesartan medoxomil treatment

Sprue-like enteropathy associated with treatment with olmesartan medoxomil, an angiotensin II receptor blocker, has been described recently. Herein, we report two patients who developed chronic severe non-bloody diarrhea, weight loss, and muscle wasting after prolonged use of olmesartan. Histologic and immunohistochemical examination of multiple duodenal biopsies revealed severe villous atrophy. Clinical signs ceased upon drug discontinuation. Physicians should be aware of this enteropathy even if olmesartan has been taken for months or years. Whether this adverse event is specific for olmesartan or is a class effect of angiotensin II receptor blockers is currently unknown. To the best of our knowledge, these case reports are the first reported in Greece.

Olmesartan-associated enteropathy: new insights on the natural history? Report of two cases

INTRODUCTION

The association between olmesartan and an enteropathy histologically indistinguishable from untreated celiac disease has recently been described. However, pathogenetic mechanisms leading to villous atrophy, prevalence, natural history and genetic background of this condition have not yet been defined.

PATIENTS

We describe here two cases of olmesartan-associated enteropathy and discuss some aspects of the natural history of this condition.

RESULTS

In both patients, an infectious episode seems to have triggered the severe malabsorption syndrome which led them to hospitalization. High titer positive antinuclear antibodies with homogeneous pattern were found.

CONCLUSIONS

Our reports add to a growing body of evidence suggesting that olmesartan-associated enteropathy should be considered in the presence of villous atrophy and negative celiac serology and in the diagnostic algorithm of non-responsive celiac disease.

Anti-proliferative effect of olmesartan on Tenon's capsule fibroblasts

AIM

To evaluate the inhibitive effect of olmesartan to fibroblast proliferation and the anti-scarring effect in Tenon's capsule, both in vitro and in vivo.

METHODS

Human primary Tenon's capsule fibroblasts were cultured in vitro, treated with up titrating concentrations of olmesartan. The rate of inhibition was tested with methyl thiazol tetrazolium (MTT) method. Real-time PCR was performed to analyze changes in mRNA expressions of the fibrosis-related factors: matrix metalloproteinase-2 (MMP-2), tissue inhibitor of metalloproteinase (TIMP-1,2) and proliferating cell nuclear antigen (PCNA). Thirty rabbits were divided into 5 groups (3, 7, 14, 21, and 28d). A rabbit conjunctiva flap model was created in each eye. Olmesartan solution was injected subconjunctivally and then evaluated its anti-proliferation and anti-fibrosis effects through the histological morphology and immunohistochemistry of MMP-2 and PCNA in each group. Only the 7d group was treated with Masson's trichrome to compare the neovascularization in the subconjunctiva area.

RESULTS

In vitro, cultured Tenon's capsule human fibroblasts showed a dose dependent inhibition by olmesartan in MTT. Olmesartan reduced mRNA expressions of MMP-2 and PCNA but increased mRNA expressions of TIMP-1 and TIMP-2. In vivo, the rabbit eyes treated with olmesartan at 3(rd), 7(th), 14(th) and 21(st) days demonstrated a significant reduced expressions of MMP-2 and PCNA compared with control eye, no significant difference observed in 28(th) day group. The cellular proliferation and neovascularization was suppressed by olmesartan in Masson's trichrome observation.

CONCLUSION

By inhibiting fibroblasts in vitro and in vivo, olmesartan prevents the proliferation and activity of fibroblasts in scar tissue formation, which might benefit glaucoma filtering surgery.

Immunopathogenesis of olmesartan-associated enteropathy

BACKGROUND

Olmesartan-associated enteropathy (OAE) is characterised by diarrhoea, nausea, vomiting, abdominal pain, weight loss and severe sprue-like enteropathy, all of which are resolved after discontinuation of olmesartan medoximil.

AIM

To determine the mechanistic similarities of OAE with coeliac sprue.

METHODS

Duodenal biopsies were extracted from OAE patients before (n = 11) or after (n = 17) discontinuation of olmesartan medoxomil (on or off olmesartan medoxomil). There were seven 'on/off' paired samples. Formalin-fixed biopsies were stained for CD8, CD4, FoxP3, IL-15R and psmad 2/3. Caco2 cells (human colonic epithelial line) were treated with olmesartan medoxomil and stained for IL-15, IL-15R and ZO-1.

RESULTS

In the 'on olmesartan medoxomil' duodenal biopsies, a significant increase in the numbers of CD8+ cells and the number of cells that are FoxP3+ (a regulatory T-cell marker) are present in the duodenum as compared to the duodenal biopsies from patients who discontinued olmesartan medoxomil. IL15R expression is also increased with olmesartan medoxomil use. Evaluation of the effect of olmesartan medoxomil upon Caco-2 cells demonstrated that IL15 expression is increased in response to olmesartan medoxomil treatment. Further, ZO-1, a tight junction protein, is disrupted in olmesartan medoxomil-treated Caco-2 cells.

CONCLUSIONS

Olmesartan-associated enteropathy shares many features with coeliac disease, including symptoms and immunopathogenic pathways, such as increased numbers of CD8+ cells and corresponding overexpression of IL15 by epithelial cells. Taken together, the treatment of epithelial cells with olmesartan medoxomil induces a response by intestinal epithelial cells that is similar to the innate effects of gluten upon the epithelium of coeliac patients.

Synthesis and Physicochemical Characterization of the Process-Related Impurities of Olmesartan Medoxomil. Do 5-(Biphenyl-2-yl)-1-triphenylmethyltetrazole Intermediates in Sartan Syntheses Exist?

During the process development for multigram-scale synthesis of olmesartan medoxomil (OM), two principal regioisomeric process-related impurities were observed along with the final active pharmaceutical ingredient (API). The impurities were identified as N-1- and N-2-(5-methyl-2-oxo-1,3-dioxolen-4-yl)methyl derivatives of OM. Both compounds, of which N-2 isomer of olmesartan dimedoxomil is a novel impurity of OM, were synthesized and fully characterized by differential scanning calorimetry (DSC), infrared spectroscopy (IR), nuclear magnetic resonance spectroscopy (NMR) and high-resolution mass spectrometry/electrospray ionization (HRMS/ESI). Their ¹H, (13)C and (15)N nuclear magnetic resonance signals were fully assigned. The molecular structures of N-triphenylmethylolmesartan ethyl (N-tritylolmesartan ethyl) and N-tritylolmesartan medoxomil, the key intermediates in OM synthesis, were solved and refined using single-crystal X-ray diffraction (SCXRD). The SCXRD study revealed that N-tritylated intermediates of OM exist exclusively as one of the two possible regioisomers. In molecular structures of these regioisomers, the trityl substituent is attached to the N-2 nitrogen atom of the tetrazole ring, and not to the N-1 nitrogen, as has been widely reported up to the present. This finding indicates that the reported structural formula of N-tritylolmesartan ethyl and N-tritylolmesartan medoxomil, as well as their systematic chemical names, must be revised. The careful analysis of literature spectroscopic data for other sartan intermediates and their analogs with 5-(biphenyl-2-yl)tetrazole moiety showed that they also exist exclusively as N-2-trityl regioisomers.