Inhibitory effect of telmisartan on the blood pressure response to angiotensin II challenge

Elucidating nonlinear pharmacokinetics of telmisartan: Integration of target-mediated drug disposition and OATP1B3-mediated hepatic uptake in a physiologically based model

Telmisartan, a selective inhibitor of angiotensin II receptor type 1 (AT1), demonstrates nonlinear pharmacokinetics (PK) when orally administered in ascending doses to healthy volunteers, but the underlying mechanisms remain unclear. This study presents a physiologically based pharmacokinetic model integrated with target-mediated drug disposition (TMDD-PBPK model) to explore the mechanism of its nonlinear PK. We employed the Cluster-Gauss Newton method for top-down analysis, estimating the in vivo Km,OATP1B3 (Michaelis-Menten constant for telmisartan hepatic uptake via Organic Anion Transporting Polypeptide 1B3) to be 2.0-5.7 nM. This range is significantly lower than the reported in vitro value of 810 nM, obtained in 0.3% human serum albumin (HSA) conditions. Further validation was achieved through in vitro assessment in plated human hepatocytes with 4.5% HSA, showing a Km of 4.5 nM. These results underscore the importance of albumin-mediated uptake effect for the hepatic uptake of telmisartan. Our TMDD-PBPK model, developed through a "middle-out" approach, underwent sensitivity analysis to identify key factors in the nonlinear PK of telmisartan. We found that the nonlinearity in the area under the concentration-time curve (AUC) and/or maximum concentration (Cmax) of telmisartan is sensitive to Km,OATP1B3 across all dosages. Additionally, the dissociation constant (Kd) for telmisartan binding to the AT1 receptor, along with its receptor abundance, notably influences PK at lower doses (below 20 mg). In conclusion, the nonlinear PK of telmisartan appears primarily driven by hepatic uptake saturation across all dose ranges and by AT1-receptor binding saturation, notably at lower doses.

Effects of telmisartan on metabolic syndrome components: a comprehensive review

Telmisartan is an antagonist of the angiotensin II receptor used in the management of hypertension (alone or in combination with other antihypertensive agents. It belongs to the drug class of angiotensin II receptor blockers (ARBs). Among drugs of this class, telmisartan shows particular pharmacologic properties, including a longer half-life than any other angiotensin II receptor blockers that bring higher and persistent antihypertensive activity. In hypertensive patients, telmisartan has superior efficacy than other antihypertensive drugs (losartan, valsartan, ramipril, atenolol, and perindopril) in controlling blood pressure, especially towards the end of the dosing interval. Telmisartan has a partial PPARγ-agonistic effect whilst does not have the safety concerns of full agonists of PPARγ receptors (thiazolidinediones). Moreover, telmisartan has an agonist activity on PPARα and PPARδ receptors and modulates the adipokine levels. Thus, telmisartan could be considered as a suitable alternative option, with multi-benefit for all components of metabolic syndrome including hypertension, diabetes mellitus, obesity, and hyperlipidemia. This review will highlight the role of telmisartan in metabolic syndrome and the main mechanisms of action of telmisartan are discussed and summarized. Many studies have demonstrated the useful properties of telmisartan in the prevention and improving of metabolic syndrome and this well-tolerated drug can be greatly proposed in the treatment of different components of metabolic syndrome. However, larger and long-duration studies are needed to confirm these findings in long-term observational studies and prospective trials and to determine the optimum dose of telmisartan in metabolic syndrome.

AT1R blocker prevents mental stress induced retrograde blood flow in overweight/obese men

The main goal was to determine the impact of mental stress (MS) on blood flow regulation in overweight/obese men. Fourteen overweight/obese men (27 ± 7 years; 29.8 ± 2.6 kg/m² ) participated in two randomized experimental sessions with oral administration of the AT1R blocker Olmesartan (40 mg; AT1RB) or placebo (PL). After 2 h, a 5-min acute MS session (Stroop Color Word Test) was administered. Blood flow was assessed at baseline and during the first 3 min of MS by vascular ultrasound in the brachial artery. Blood was collected before (baseline) and during mental stress (MS) for measurement of nitrite (chemiluminescence) and endothelin-1 (ELISA kit). The AT1R blocker was able to reverse the MS responses observed in the placebo session for retrograde flow (p < 0.01), retrograde SR (p < 0.01) and oscillatory shear index (p = 0.01). Regarding vasoactive substances, no differences were observed in ET-1 (p > 0.05) responses to MS between experimental sessions. However, for nitrite responses, the administration of the AT1R blocker was able to increase circulating levels of NO (p = 0.03) Blockade of AT1R appears to prevent the decrease in endothelial function by reducing low shear stress and maintaining the vasoactive substances balance after MS in overweight/obese men.

Optimization of Pharmacotherapy Within the Framework of a Patient-oriented Approach in the Treatment of Hypertension in Multimorbidity Patients (Clinical Case and Literature Review)

Arterial hypertension (AH) remains one of the main causes of disability and death worldwide, including in Russia. At the same time, the risks of coronary and cerebrovascular events increase in the presence of additional risk factors. The most common modifiable risk factors are metabolic disorders, including pre-diabetes, dyslipidemia, peripheral arterial atherosclerosis, and obesity, which also imposes certain features on the choice of optimal pharmacotherapy. Currently, the terminology of comorbid conditions continues to be discussed depending on their pathogenesis and the presence or absence of dominance of one disease over others, i.e. polymorbidity, comorbidity and multimorbidity. At the same time, “associative polymorbidity” is distinguished with a certain set of diseases that often occur in conjunction with each other with individual susceptibility of the body. One of the most common phenotypes of polymorbidity occurring in all age groups in both sexes is cardiometabolic, which is based on the formation of insulin resistance, sympathetic overactivity and chronic inflammation. This article provides a clinical example of the use of a fixed combination of angiotensin II receptor blocker telmisartan and calcium channel blocker amlodipine with the addition of an I1-imidazoline receptor agonist moxonidine in real clinical practice in a polymorbid cardiometabolic patient with target organ damage (left ventricular hypertrophy and microalbuminuria). High antihypertensive (favorable effect on 24-hour blood pressure, especially in the early morning) and organoprotective effectiveness of this combination, its possibilities in correcting additional risk factors (reduced heart rate, body weight and a positive effect on metabolic parameters), due to a synergistic effect on the central pathogenetic mechanisms of hypertension and obesity – insulin resistance and sympathetic overactivity.

Pharmacokinetic Interaction Between Telmisartan and Rosuvastatin/Ezetimibe After Multiple Oral Administration in Healthy Subjects

INTRODUCTION

Telmisartan, rosuvastatin and ezetimibe are commonly recommended as combination therapies. However, the pharmacokinetic (PK) interaction among these therapeutic drugs has not been clearly reported. The objective of this study was to investigate possible interactions between telmisartan monotherapy and a fixed-dose combination (FDC) of rosuvastatin/ezetimibe.

METHODS

A randomized, open-label, multiple oral dose, three-treatment, three-period, six-sequence crossover study was conducted in healthy male volunteers. Monotherapy and cotherapy with telmisartan (80 mg) or a FDC of rosuvastatin and ezetimibe (20/10 mg) were compared after once-daily treatment for 7 days. The PK profiles for telmisartan, rosuvastatin, total ezetimibe (ezetimibe + exetimibe glucuronide) and ezetimibe were evaluated up to 48 h after the last dose. There was a 14-day washout period between each treatment.

RESULTS

The geometric mean ratios (GMRs) and 90% confidence intervals (CIs) for the peak plasma concentration at steady state (C_max,ss) and area under the plasma concentration-time curve during the dosing interval at steady state (AUC_τ,ss) were 1.258 (1.072-1.475) (P = 0.020) and 1.264 (1.167-1.370) (P < 0.001) for telmisartan, 0.796 (0.723-0.878) (P < 0.001) and 0.904 (0.842-0.970) (P = 0.021) for total ezetimibe and 1.237 (1.081-1.416) (P = 0.012) and 0.988 (0.899-1.086) (P = 0.832) for ezetimibe, respectively. With rosuvastatin, the GMR (90% CI) was 2.616 (2.287-2.992) (P < 0.001) for C_max,ss and 1.265 (1.168-1.369) (P < 0.001) for AUC_τ,ss. No serious adverse events or clinically significant results were reported.

CONCLUSIONS

The coadministration of multiple doses of telmisartan and rosuvastatin/ezetimibe led to a mild increase in systemic exposure with respect to telmisartan and rosuvastatin and a nonsignificant change in exposure to total ezetimibe and ezetimibe, which was not considered clinically significant without safety concerns. Furthermore, for the generalizability of the clinical effects, a large-scaled clinical study might be required in patients with hypertension and dyslipidemia.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov registry number: NCT03802526.

How to Choose the Optimal Single-Pill Combination of the First-Line Antihypertensive Drugs? The Benefits of Amlodipine and Telmisartan Combination

In patients with arterial hypertension (AH), an extremely important measure of the effectiveness of antihypertensive drugs (AHD) is not only a direct decrease in blood pressure (BP), but also its stable control throughout the 24 hours, preventing excessive morning surge and increased BP variability, which in turn are recognized cardiovascular risk factors. Currently, in the vast majority of hypertensive patients, the main antihypertensive therapy approach is using single-pill combinations (SPC) of AHD. Among the first-line combinations for a wide range of patients with AH and no special clinical conditions is amlodipine/telmisartan SPC. Distinctive features of these drugs, on the one hand, are unique pharmacological properties, consisting in an ultra-long antihypertensive effects, superior to other AHD in their classes; and on the other hand, there is an large body of evidence from numerous clinical trials confirming their high antihypertensive and target-organ protective potential as well as excellent capabilities in cardiovascular risk reduction. To assess the AHD effectiveness extent, several parameters have been proposed, of which the most rational and useful is the smoothness index, calculated using the ambulatory blood pressure monitoring data. Smoothness index describes both the degree of BP reduction and its distribution during the monitoring period. This index inversely associates with the changes in BP variability, and has predictive value in relation to the hypertension-mediated organ damage regression during different antihypertensive regimens. Amlodipine/telmisartan SPC has also been studied in many trials, including comparative ones with other AHD. In these works its direct powerful antihypertensive effect and a pronounced beneficial impact on the smoothness index have been proved, demonstrating stable BP control throughout the 24 hours (especially in the most dangerous morning hours), and also a decrease in BP variability. Therefore, amlodipine/telmisartan SPC can effectively reduce cardiovascular risk and improve prognosis in patients with AH.

Current Trends in the Treatment of Hypertension: Focus on Improving Prognosis. The Capabilities of an Amlodipine/Telmisartan Single-Pill Combination

Nowadays, the modern approach to antihypertensive therapy is to prescribe in the most hypertensive patients fixed-dose combinations of antihypertensive drugs as initial therapy. This concept is reflected in the latest revisions of European and Russian guidelines for the management of arterial hypertension (AH). Above mentioned principle is referred as “single-pill combination” strategy and is given high priority in clinical practice with a high evidence level. According to this approach, one of the possible first line single-pill combinations is the combination of an angiotensin II receptor blocker and a calcium channel blocker. In both classes, the reference and the best representatives include, respectively, telmisartan and amlodipine, as a result of broad experience in their practical application and, most importantly, extensive body of evidence regarding to its effectiveness and safety. Both antihypertensive drugs are distinguished by an extra-longstanding antihypertensive effect that exceeds such one of other representatives in their classes, thereby a stable blood pressure control throughout the day is realized, and most importantly, in the early morning hours, that are the most dangerous in terms of adverse cardiovascular and cerebrovascular events. Another important telmisartan and amlodipine characteristics is their targetorgan protective properties, which is realized at all the levels. In addition, telmisartan has a unique ability to activate PPAR-у-receptors and improves the carbohydrate metabolism and lipid profile, which is advantageous in patients with concomitant metabolic syndrome and diabetes mellitus. The telmisartan and amlodipine features and their proven ability to improve prognosis in hypertensive patients served as background for creating a singlepill combination of these antihypertensive drugs, which fully meet with the requirements of current clinical guidelines for AH management and in which these drugs synergistically coupling resulting in more effective blood pressure control, increases the reliability of target-organ protection, and also improves the therapy safety profile.

Pharmacokinetic Interaction Between Rosuvastatin, Telmisartan, and Amlodipine in Healthy Male Korean Subjects: A Randomized, Open-label, Multiple-dose, 2-period Crossover Study

PURPOSE

Rosuvastatin, a hydroxy methylglutaryl coenzyme A reductase inhibitor; telmisartan, an angiotensin receptor blocker; and amlodipine, a calcium channel inhibitor, are commonly prescribed together for the treatment of hypertension nonresponsive to monotherapy and accompanied by dyslipidemia. However, the pharmacokinetic interactions among these 3 substances are not well understood. The aim of this study was to investigate the pharmacokinetic drug-drug interactions among rosuvastatin, telmisartan, and amlodipine in a healthy Korean male population.

METHODS

In both parts of this randomized, open-label, multiple-dose, 2-part, 2-period crossover study, subjects aged 19 to 55 years were enrolled. In part 1, each subject received rosuvastatin 20 mg with and without 2 fixed-dose combination (FDC) tablets of telmisartan/amlodipine 40/5 mg, once daily for 9 consecutive days. In part 2, each subject received 2 FDC tablets of telmisartan/amlodipine 40/5 mg with and without rosuvastatin 20 mg, once daily for 9 consecutive days. In both parts, there was a 13-day washout period between treatments. Pharmacokinetic samples were collected up to 72 hours after the last dose in subjects who received rosuvastatin only, and up to 144 hours after the last dose in subjects who received telmisartan/amlodipine with or without rosuvastatin. Adverse events (AEs) were assessed via interviews and physical examinations.

FINDINGS

Forty-eight subjects were enrolled, of whom 19 in part 1 and 22 in part 2 completed the study. In Part 1, the 90% CIs of the geometric mean ratios (GMRs) (coadministration of rosuvastatin and telmisartan/amlodipine to monotherapy with rosuvastatin) of the primary pharmacokinetic parameters (AUCτ and Cmax,ss) were: rosuvastatin, 1.1436 to 1.3059 and 1.8970 to 2.3514, respectively; and N-desmethyl rosuvastatin, 0.8441 to 1.0200 and 1.1971 to 1.5457. In part 2, the 90% CIs of the GMRs (coadministration to monotherapy with telmisartan/amlodipine) were: telmisartan, 1.1204 to 1.4228 and 0.9940 to 1.5940; amlodipine, 0.9705 to 1.0636 and 0.9813 to 1.0779. There were no significant differences in the prevalences of AEs between the treatments, and all reported AEs were mild or moderate.

IMPLICATIONS

These results demonstrate that when rosuvastatin, telmisartan, and amlodipine are coadministered to healthy male subjects, pharmacokinetic exposure increases with respect to rosuvastatin and telmisartan, whereas no change occurs with respect to amlodipine. However, based on previous analyses, the degree of increase in the exposure observed was not regarded as clinically significant. All treatments were well-tolerated.

Angiotensin II type 1 receptor antagonists in animal models of vascular, cardiac, metabolic and renal disease

We have reviewed the effects of angiotensin II type 1 receptor antagonists (ARBs) in various animal models of hypertension, atherosclerosis, cardiac function, hypertrophy and fibrosis, glucose and lipid metabolism, and renal function and morphology. Those of azilsartan and telmisartan have been included comprehensively whereas those of other ARBs have been included systematically but without intention of completeness. ARBs as a class lower blood pressure in established hypertension and prevent hypertension development in all applicable animal models except those with a markedly suppressed renin-angiotensin system; blood pressure lowering even persists for a considerable time after discontinuation of treatment. This translates into a reduced mortality, particularly in models exhibiting marked hypertension. The retrieved data on vascular, cardiac and renal function and morphology as well as on glucose and lipid metabolism are discussed to address three main questions: 1. Can ARB effects on blood vessels, heart, kidney and metabolic function be explained by blood pressure lowering alone or are they additionally directly related to blockade of the renin-angiotensin system? 2. Are they shared by other inhibitors of the renin-angiotensin system, e.g. angiotensin converting enzyme inhibitors? 3. Are some effects specific for one or more compounds within the ARB class? Taken together these data profile ARBs as a drug class with unique properties that have beneficial effects far beyond those on blood pressure reduction and, in some cases distinct from those of angiotensin converting enzyme inhibitors. The clinical relevance of angiotensin receptor-independent effects of some ARBs remains to be determined.

Pharmacokinetic interaction between rosuvastatin and telmisartan in healthy Korean male volunteers: a randomized, open-label, two-period, crossover, multiple-dose study

PURPOSE

Rosuvastatin, a 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitor, and telmisartan, an angiotensin receptor blocker, are commonly prescribed in combination for the treatment of dyslipidemia accompanied by hypertension. However, the nature of the pharmacokinetic interaction between the 2 drugs is not clearly understood. The goal of the present study was to investigate the pharmacokinetic drug-drug interaction between rosuvastatin and telmisartan in a healthy Korean population.

METHODS

This was a randomized, 2-part, open-label, 2-period, crossover, multiple-dose study, with each part composed of different subjects between the ages of 20 and 55 years. In part 1, each subject received rosuvastatin 20 mg with and without telmisartan 80 mg once daily for 6 consecutive days. In part 2, each subject received telmisartan 80 mg with and without rosuvastatin 20 mg once daily for 6 consecutive days. In both parts, there was a 16-day washout period between mono- and coadministration. Blood samples were collected up to 72 hours after the last dose. Adverse events (AEs) were evaluated through interviews and physical examinations.

FINDINGS

In part 1, the 90% CIs of the geometric mean ratios for the primary pharmacokinetic parameters for coadministration of the 2 drugs to monoadministration of each drug were 1.0736-1.2932 for AUCτ and 1.7442-2.3229 for Cmax,ss for rosuvastatin and 0.9942-1.1594 for AUCτ and 1.3593-1.7169 for Cmax,ss for N-desmethyl rosuvastatin, whereas in part 2, the CIs were 1.0834-1.2672 for AUCτ and 1.1534-1.5803 for Cmax,ss for telmisartan. The most frequently noted AE was cough in part 1, which occurred in 2 subjects receiving the combination therapy, and oropharyngeal pain in part 2, which occurred in 3 subjects receiving the combination therapy. All reported AEs were mild or moderate, and there was no significant difference in incidence between the treatments.

IMPLICATIONS

These findings demonstrated that rosuvastatin and telmisartan mutually affected each other's pharmacokinetics, suggesting a possibility of drug-drug interaction. However, based on dose-response characteristics of the 2 drugs and previous results from other interaction studies, the degree of drug interaction observed in this study was not regarded as clinically significant. All treatments were well tolerated, with no serious AEs observed. ClinicalTrials.gov identifier: NCT01992601.

Telmisartan/hydrochlorothiazide: a new fixed dose combination

Many patients with hypertension require two or more antihypertensive drugs with complementary mechanisms of action to lower their blood pressure and attain the therapeutic goals specified in internationally accepted guidelines. Yet, these latter guidelines offer the choice of fixed dose combinations as possible first-step therapies. The angiotensin II type 1-receptor antagonist telmisartan and the diuretic hydrochlorothiazide are two antihypertensive agents that have a well-recognized clinical efficacy. Their combination was shown in randomized, controlled trials to be more effective than each agent alone in lowering blood pressure, due to a dual and synergistic mechanism. Indeed, combining telmisartan with hydrochlorothiazide enhances the antihypertensive efficacy of telmisartan in almost two-thirds of hypertensive patients with mild-to-moderate hypertension. The pharmacokinetics and -dynamics of the combination are similar to monotherapy, and the addition of hydrochlorothiazide to telmisartan does not modify the excellent tolerability profile of the drug.

Effect of Telmisartan on Cerebral and Systemic Haemodynamics in Patients with Recent Ischaemic Stroke: A Randomised Controlled Trial

High blood pressure (BP) is common in acute stroke and is independently associated with a poor outcome. Lowering BP might improve outcome if cerebral blood flow (CBF) is unaffected in the presence of dysfunctional autoregulation. We investigated the effect of telmisartan on systemic and cerebral haemodynamics in patients with recent stroke. Patients with ischaemic stroke (<5 days) were randomised to 90 days of telmisartan (80 mg) or placebo. CBF (primary outcome) was measured using xenon CT at baseline and 4 hours. BP and transcranial doppler (TCD) were performed at baseline, 4 hours after-treatment, and on days 4, 7, and 90. Cerebral perfusion pressure and zero filling pressure (ZFP) were calculated. Of a planned 24 patients, 17 were recruited. Telmisartan significantly accentuated the fall in systolic and diastolic BP over 90 days (treatment-time interaction p=0.047, p=0.003, resp.) but did not alter BP at 4 hours after treatment (171/99 versus 167/87 mmHg), CBF, or CBF velocity. ZFP was significantly lower in the treatment group (p=0.018). Impairment at 7 days and dependency at 90 days did not differ between the groups. In this underpowered study, telmisartan did not significantly alter BP or CBF after the first dose. Telmisartan reduced BP over the subsequent 90 days and significantly lowered ZFP. This trial is registered with ISRCTN 41456162.

A systematic comparison of the properties of clinically used angiotensin II type 1 receptor antagonists

Angiotensin II type 1 receptor antagonists (ARBs) have become an important drug class in the treatment of hypertension and heart failure and the protection from diabetic nephropathy. Eight ARBs are clinically available [azilsartan, candesartan, eprosartan, irbesartan, losartan, olmesartan, telmisartan, valsartan]. Azilsartan (in some countries), candesartan, and olmesartan are orally administered as prodrugs, whereas the blocking action of some is mediated through active metabolites. On the basis of their chemical structures, ARBs use different binding pockets in the receptor, which are associated with differences in dissociation times and, in most cases, apparently insurmountable antagonism. The physicochemical differences between ARBs also manifest in different tissue penetration, including passage through the blood-brain barrier. Differences in binding mode and tissue penetration are also associated with differences in pharmacokinetic profile, particularly duration of action. Although generally highly specific for angiotensin II type 1 receptors, some ARBs, particularly telmisartan, are partial agonists at peroxisome proliferator-activated receptor-γ. All of these properties are comprehensively reviewed in this article. Although there is general consensus that a continuous receptor blockade over a 24-hour period is desirable, the clinical relevance of other pharmacological differences between individual ARBs remains to be assessed.

Telmisartan: from lowering blood pressure to end-organ protection

The principal aim in the treatment of patients with high blood pressure is to ensure a maximum reduction in the total risk of cardiovascular morbidity and mortality. The renin-angiotensin system plays an important role in volume homeostasis and blood pressure regulation. The angiotensin receptor blockers control high blood pressure by preventing the binding of angiotensin II to the subtype 1 receptor, which is believed to mediate most of the physiologic actions of angiotensin II relevant to the regulation of blood pressure. Telmisartan is a widely used angiotensin receptor blocker with distinct pharmacokinetic and pharmacodynamic properties. Due to its long duration of action, it compares favorably with other angiotensin receptor blockers. Latest data from clinical trials and newest research regarding telmisartan will be reviewed in this article.

Telmisartan: a different angiotensin II receptor blocker protecting a different population?

The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET()) showed that the angiotensin II receptor blocker (ARB) telmisartan was as protective as the reference-standard ramipril in a broad cross-section of patients at increased cardiovascular risk, but was better tolerated. Telmisartan has a unique profile among ARBs, with a high affinity for the angiotensin II type 1 receptor, a long duration of receptor binding, a high lipophilicity and a long plasma half life. This leads to sustained and powerful blood pressure lowering when compared with the first marketed ARBs, such as losartan and valsartan. Some pharmacological properties of telmisartan clearly distinguish it from other members of the ARB class and may contribute to the clinical effects seen with telmisartan. A class effect for ARBs cannot be assumed. To date, telmisartan is the only ARB that has been shown to reduce cardiovascular risk in at-risk cardiovascular patients.

New standards in hypertension and cardiovascular risk management: focus on telmisartan

Blockade of the renin–angiotensin system is an important approach in managing high blood pressure, and has increasingly been shown to affect cardiovascular disease processes mediated by angiotensin II throughout the cardiovascular and renal continua. Telmisartan is an angiotensin II receptor blocker (ARB) displaying unique pharmacologic properties, including a longer half life than any other ARB, that result in large and sustained reductions of blood pressure. In patients with mild-to-moderate hypertension, telmisartan has proved superior to other antihypertensive agents (valsartan, losartan, ramipril, perindopril, and atenolol) in controlling blood pressure particularly towards the end of the dosing interval. There is also clinical evidence that telmisartan reduces left ventricular hypertrophy, reduces arterial stiffness and the recurrence of atrial fibrillation, and confers renoprotection. The ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET^®) study has demonstrated that telmisartan has similar cardiovascular protective effects to ramipril in a large, high-risk patient population but was better tolerated. The powerful and sustained blood pressure control apparent in clinical trials, together with cardiovascular protection and tolerability demonstrated in ONTARGET^® means that telmisartan may be a preferred option for patients with hypertension.

Telmisartan Inhibits CD4-Positive Lymphocyte Migration Independent of the Angiotensin Type 1 Receptor via Peroxisome Proliferator-Activated Receptor-γ

Migration of CD4-positive lymphocytes into the vessel wall represents an important step in early atherogenesis. Telmisartan is an angiotensin type 1 receptor (AT1R) blocker with peroxisome proliferator-activated receptor (PPAR)-γ–activating properties. The present study examined the effect of telmisartan on CD4-positive cell migration and the role of PPARγ in this context. CD4-positive lymphocytes express both the AT1R and PPARγ. Stimulation of CD4-positive lymphocytes with stromal cell-derived factor (SDF)-1 leads to a 4.1±3.1-fold increase in cell migration. Pretreatment of cells with telmisartan reduces this effect in a concentration-dependent manner to a maximal 1.6±0.7-fold induction at 10 μmol/L of telmisartan ( P <0.01 compared with SDF-1–treated cells; n=22). Three different PPARγ activators, rosiglitazone, pioglitazone, and GW1929, had similar effects, whereas eprosartan, a non-PPARγ–activating AT1R blocker, did not affect chemokine-induced lymphocyte migration. Telmisartan’s effect on CD4-positive lymphocyte migration was mediated through an early inhibition of chemokine-induced phosphatidylinositol 3-kinase activity. Downstream, telmisartan inhibited F-actin formation, as well as intercellular adhesion molecule-3 translocation. Transfection of CD4-positive lymphocytes with PPARγ small interfering RNA abolished telmisartan’s effect on migration, whereas blockade of the AT1R had no such effect. Telmisartan inhibits chemokine-induced CD4-positive cell migration independent of the AT1R via PPARγ. These data provide a novel mechanism to explain how telmisartan modulates lymphocyte activation by its PPARγ-activating properties.

Pharmacoeconomics and quality of life analysis of telmisartan in hypertension treatment

Hypertension is a major public health problem, being one of the leading causes of death and disability worldwide and a major risk factor for cardiovascular disease. The renin-angiotensin-aldosterone system plays an important role in volume homeostasis and blood pressure regulation, and is a target for several groups of pharmaceutical agents. Telmisartan, a highly selective AT1 receptor antagonist, fulfills all new criteria for antihypertensive agents: high effectiveness, high specificity, high compliance and fewer adverse effects. Several clinical trials and the clinical practice setting indicate substantial evidence that telmisartan, either as monotherapy or in combination with other antihypertensive drugs, provides long-term antihypertensive efficacy. In fact, telmisartan has the property to sustain blood pressure control throughout the 24-h dosage interval. Furthermore, telmisartan can play an important role in improving compliance, because of its documented good tolerability profile, which limits the adverse effects. This article provides the most recent data of the pharmacoeconomic position of telmisartan and its treatment effects on quality of life.

Acute effects of renin-angiotensin system blockade on arterial function in hypertensive patients

The acute effects of the renin-angiotensin system (RAS) blockers may be important in some clinical settings. To assess the acute impact of such drugs on arterial function, we studied the effects of captopril 25 mg, quinapril 20 mg and telmisartan 80 mg on 100 hypertensive patients, according to a randomized, double-blind, placebo-controlled study. Central (aortic) blood pressure (BP) and augmentation index (AIx, a measure of wave reflections), as well as flow-mediated dilatation (FMD) of the brachial artery and forearm blood flow (FBF) (measures of conduit and resistance artery endothelial function, respectively), were evaluated before and 2 h after oral drug administration. Compared to placebo, captopril and quinapril decreased central systolic (by 7.5 mm Hg, P<0.05 and by 12.3 mm Hg, P<0.001) and diastolic BP (by 4.9 mm Hg, P<0.01 and by 8.4 mm Hg, P<0.001), whereas telmisartan had no significant effect (P=NS). Additionally, AIx was reduced after quinapril (absolute decrease of 7.2%, P<0.01) and marginally after captopril (decrease of 4.7%, P=0.07). Only quinapril led to a beneficial change of FMD (absolute increase of 2.7%, P<0.001). No treatment was related to significant changes of peak hyperaemic or 3-min hyperaemic FBF. In adjusted analyses, all the favourable alterations induced by quinapril were independent of potential confounding haemodynamic factors. Our data show that acute RAS inhibition with quinapril (20 mg) may be more beneficial in terms of arterial function and central haemodynamics compared to captopril (25 mg) or telmisartan (80 mg). Further studies are needed to investigate whether these acute arterial effects of quinapril are clinically significant.

AT1 receptor blockade prevents the decrease in conduit artery flow-mediated dilatation during NOS inhibition in humans

Whether AT(1) (angiotenin II type 1) receptor blockade can prevent the decrease in conduit artery FMD (flow-mediated dilatation) during NOS (nitric oxide synthase) inhibition by alternative endothelial pathways has not been explored previously in humans. In 12 healthy subjects, we measured radial artery diameter (echotracking) and flow (Doppler) during FMD induced by sustained reactive hyperaemia during a control period and following NOS inhibition [1.5 mg.min(-1).l(-1) L-NMMA (N(G)-monomethyl-L-arginine)], after a single oral administration of telmisartan (80 mg) or placebo, using a randomized double-blind cross-over design. In six volunteers, we also assessed the roles of prostacyclin and EDHF (endothelium-derived hyperpolarizing factor) during radial FMD after AT(1) receptor blockade by oral administration of aspirin (500 mg) alone, aspirin+L-NMMA or aspirin+L-NMMA+fluconazole (a cytochrome epoxygenases inhibitor; 0.37 mg.min(-1).l(-1)). Telmisartan did not affect radial artery FMD in the control period (10.9+/-0.6% with placebo compared with 9.9+/-0.7% with telmisartan), but prevented its decrease after L-NMMA (9.3+/-0.8% with placebo compared with 12.6+/-1.2% with telmisartan; P<0.05) with no modification in baseline parameters, hyperaemia and radial artery endothelium-independent dilatation to sodium nitroprusside. Moreover, in telmisartan-treated subjects, radial artery FMD, compared with control (9.0+/-1.0%), was not modified by aspirin alone (9.4+/-0.7%) or associated with L-NMMA (9.5+/-0.5%), but was reduced by the combination of aspirin, L-NMMA and fluconazole (7.5+/-0.6%; P<0.05). These results demonstrate that AT(1) receptor blockade prevents the decrease in conduit artery FMD during NOS inhibition in humans, suggesting the development of a compensatory endothelial mechanism. This mechanism appears to be independent of prostacyclin and could possibly be related to an EDHF release.

Effective treatment of hypertension by AT(1) receptor antagonism: the past and future of telmisartan

Lowering blood pressure is the most effective treatment method to ensure a reduction in the total risk for cardiovascular morbidity and mortality. The renin-angiotensin system plays an important role in volume homeostasis and blood pressure regulation and is a target for several groups of pharmaceutical agents. Angiotensin II receptor blockers represent the newest class of antihypertensive compounds. They prevent the binding of angiotensin II to the subtype 1 receptor (AT(1)), which is believed to mediate most of the physiological actions relevant to the regulation of blood pressure. Telmisartan, a widely used AT(1) receptor antagonist, is a highly selective compound with high potency, a long duration of action and a tolerability profile similar to placebo. Numerous randomized clinical trials and community-based studies have demonstrated that oral telmisartan and combinations of telmisartan with hydrochlorothiazide are at least as effective in lowering blood pressure as all other hypertensive medications. This has been demonstrated in different populations of adult patients with mild-to-moderate essential hypertension, including patients with coexisting Type 2 diabetes, metabolic syndrome or renal impairment. Several large-scale, long-term, clinical endpoint studies are in progress to assess the beneficial effects of telmisartan on hypertension-related end-organ damage in patients at high risk of renal, cardiac and vascular damage whose blood pressure is well controlled. The most recent data from clinical trials and latest research regarding telmisartan will be reviewed in this article.

Telmisartan/hydrochlorothiazide in the treatment of hypertension

Telmisartan blocks the detrimental actions of angiotensin II mediated via the angiotensin type 1 receptor. Unique features of telmisartan are high lipophilicity and a long terminal elimination half-life (~ 24 h). Telmisartan/hydrochlorothiazide is indicated for hypertensive patients unable to achieve target blood pressure with either monotherapy. Fixed-dose combination tablets containing telmisartan 40 or 80 mg and hydrochlorothiazide 12.5 mg are widely available; in addition, telmisartan/hydrochlorothiazide 80/25 mg is available in the USA. Telmisartan/hydrochlorothiazide is superior to losartan/hydrochlorothiazide and valsartan/hydrochlorothiazide in maintaining blood pressure control in the risky early morning hours at the end of the dosing interval. Furthermore, telmisartan/ hydrochlorothiazide provides superior 24-h mean blood pressure reduction and is better tolerated than amlodipine/hydrochlorothiazide in elderly patients with predominantly systolic hypertension. Telmisartan has the potential to confer additional reno- and cardioprotection to that due to blood pressure control. The cardioprotective activity of renin–angiotensin system blockade with telmisartan alone and in combination with ramipril is currently being evaluated in the ONgoing Telmisartan Alone and in combination with Ramipril Global Endpoint Trial (ONTARGET) and the Telmisartan Randomized AssessmeNt Study in aCE iNtolerant subjects with cardiovascular Disease (TRANSCEND). In total, 31,546 patients have been enrolled worldwide and are being followed for up to 5.5 years.

Telmisartan/Hydrochlorothiazide in comparison with losartan/hydrochlorothiazide in managing patients with mild-to-moderate hypertension

Hypertension is risk factor for cardiovascular morbidity and mortality, and stroke. A critical surge in blood pressure occurs during the early morning hours coincident with increased incidences of myocardial infarction, unstable angina, stroke and sudden cardiac death. This suggests that, in patients with hypertension, it may be important to maintain the efficacy of antihypertensive medication over the 24-h dosing interval, especially in the risky early morning hours. In order to evaluate the antihypertensive efficacies of fixed-dose combinations of angiotensin II receptor blockers with hydrochlorothiazide (HCTZ) 12.5 mg, a multicenter, randomized, prospective, open-label, blinded-endpoint study was performed in 805 patients with mild-to-moderate hypertension randomized to once-daily treatment with telmisartan 40 mg plus HCTZ (T40/H12.5), losartan 50 mg plus HCTZ (L50/H12.5), or telmisartan 80 mg plus HCTZ (T80/H12.5), with the primary objective of comparing T40/H12.5 with L50/H12.5 and evaluating the additional response of T80/H12.5. Efficacy was assessed by ambulatory blood pressure monitoring (ABPM), clinic seated cuff sphygmomanometry and calculated responder rates after 6 weeks' active treatment. The primary endpoint was reduction from baseline in the last 6-h mean (relative to dosing) diastolic blood pressure (DBP) measured using 24-h ABPM. Compared with the L50/H12.5 group, the mean reductions in the last 6-h mean DBP for the T40/H12.5 and T80/H12.5 groups were significantly greater: -2.0 mmHg (p=0.0031) and -2.8 mmHg (p=0.0003), respectively. We conclude that T40/H12.5 provided clinically and statistically significantly superior blood pressure reductions compared with L50/H12.5 during the last 6 h of the 24-h dosing interval, which corresponds to the high-risk early-morning hours, and that T80/H12.5 provided additional blood pressure reductions.

Long-Term Renoprotective Effects of Standard Versus High Doses of Telmisartan in Hypertensive Nondiabetic Nephropathies

BACKGROUND

This report describes an open randomized study intended to evaluate the long-term renoprotective effects of "standard" (80 mg once daily) versus "high" (80 mg twice daily) doses of telmisartan in hypertensive patients without diabetes with biopsy-proven chronic proteinuric nephropathies.

METHODS

We included 78 patients (age, 43.5 +/- 13.2 years; 71.8% men). After a 4-week wash-out period, patients were randomly assigned to telmisartan, 80 mg once daily (n = 40) or 80 mg twice daily (n = 38), during a mean follow-up of 24.6 +/- 2.2 months.

RESULTS

Baseline characteristics were similar in both groups, including blood pressure, renal function, and proteinuria. Blood pressure control did not differ between groups during follow-up. In the group administered telmisartan, 80 mg once daily, serum creatinine level increased from 1.6 +/- 0.6 to 2.7 +/- 0.9 mg/dL (141 +/- 52 to 239 +/- 80 micromol/L), and estimated creatinine clearance declined from 68 +/- 30 to 50 +/- 34 mL/min (1.13 +/- 0.50 to 0.83 +/- 0.57 mL/s), whereas in those administered 80 mg twice daily, serum creatinine (1.6 +/- 0.7 to 1.6 +/- 0.8 mg/dL [141 +/- 62 to 141 +/- 71 micromol/L]) and estimated creatinine clearance values (67 +/- 38 to 74 +/- 38 mL/min [1.12 +/- 0.63 to 1.23 +/- 0.63 mL/s]) did not change during the study. The decrease in proteinuria was more pronounced (P < 0.01) in patients administered the high dose of telmisartan compared with those treated with the standard dose. Serum potassium levels and lipid profiles did not change significantly in either group.

CONCLUSION

Long-term administration of high doses of telmisartan seems to improve the efficacy of the drug to decrease proteinuria and slow the progression to end-stage renal failure in nondiabetic hypertensive renal disease.

A double-blind ambulatory blood pressure monitoring study of the efficacy and tolerability of once-daily telmisartan 40 mg in comparison with losartan 50 mg in the treatment of mild-to-moderate hypertension in Taiwanese patients

Ambulatory blood pressure monitoring (ABPM) was used to compare the efficacy and tolerability of once-daily telmisartan 40 mg and once-daily losartan 50 mg in Taiwanese patients with mild-to-moderate essential hypertension in a randomised, double-blind, double-dummy, parallel-group study. The initial 2-week placebo run-in phase was followed by randomisation to treatment with telmisartan 40 mg (n = 31) or losartan 50 mg (n = 30) for 6 weeks. The reduction in 18- to 24-h mean (SE) ambulatory diastolic blood pressure (DBP) from baseline was significantly greater with telmisartan 40 mg (-12.1 +/- 1.6 mmHg, p = 0.036) than with losartan 50 mg (-7.0 +/- 1.8 mmHg). The reduction in 18- to 24-h mean (SE) ambulatory systolic blood pressure (SBP) from baseline was also greater with telmisartan 40 mg (-16.0 +/- 2.4 mmHg) than with losartan 50 mg (-11.8 +/- 2.7 mmHg), but did not achieve statistical significance. Telmisartan was well tolerated; no serious adverse events occurred.

Regression of left ventricular hypertrophy and improvement of diastolic function in hypertensive patients treated with telmisartan

OBJECTIVES

The study was designed to test whether or not the angiotensin II receptor blocker telmisartan brings about regression of left ventricular (LV) concentric hypertrophy and whether or not these changes are associated with improved diastolic filling.

METHODS

An echocardiographic follow-up study was performed in 85 hypertensive patients (systolic blood pressure [SBP] >140 mmHg, diastolic blood pressure [DBP] >90 mmHg) and mild-to-moderate LV hypertrophy (LV mass index related to body surface area [LVMI] 117-150 g/m2 for men and 105-150 g/m2 for women) treated with telmisartan monotherapy 40-80 mg once daily for 1 year. Blood pressure, LVMI, left atrial (LA) volumes, and diastolic function were determined at baseline and after 3, 6, 9, and 12 months of treatment. Blood pressure was also monitored at all visits. Diastolic function was assessed by examination of transmitral inflow and pulmonary vein flow patterns.

RESULTS

Telmisartan reduced blood pressure; after 12 months, the mean+/-S.D. SBP and DBP were reduced from 144+/-10 to 126+/-8 mmHg (p<0.001) and from 98+/-8 to 86+/-7 mmHg (p<0.001), respectively. The LVMI was decreased from 119+/-7 to 109+/-3 g/m2 (p<0.001) after 12 months' telmisartan treatment. All patients had diastolic dysfunction at baseline. After 12 months' telmisartan treatment, a normal pattern of transmitral inflow was present in 21% of patients. The regression of LV hypertrophy observed after 12 months was associated with increased peak early diastolic velocity/peak late diastolic velocity ratio from 0.60+/-0.18 to 0.83+/-0.20 (p<0.001), shortened isovolumic relaxation time (IVRT) from 110+/-13 to 105+/-13 ms (p<0.001), and decreased deceleration time from 229+/-30 to 215+/-28 ms (p=0.002). Univariate analysis showed that shortened IVRT was related to a reduction in the LVMI and LA maximal and minimal volumes. In the multivariate analysis, the reduction in LVMI and the reduction in LA maximal and minimal volumes were independently associated with IVRT reduction.

CONCLUSIONS

Telmisartan 40-80 mg is effective in LV hypertrophy regression in hypertensive patients. The reduction in LVMI due to telmisartan monotherapy was associated with a significant improvement of diastolic filling parameters and with a significant reduction of LA volumes.

Effect of telmisartan 80 mg once daily on 24-h blood pressure profile in patients with mild-to-moderate hypertension failing to respond to prior antihypertensive therapy

Blood pressure is not adequately controlled in almost 50% of patients with hypertension who are in receipt of antihypertensive therapy. This multicentre, prospective, open-label trial was designed to determine whether or not once-daily telmisartan 80 mg reduced blood pressure during the last 6 h of the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive therapy. The study comprised 100 patients (47 males, 53 females) who had failed to respond satisfactorily to prior treatment given for a minimum of 3 months. At screening, 24-h ambulatory blood pressure monitoring (ABPM) was conducted after the patient had been treated with the currently prescribed antihypertensive medication. Following 5 weeks of telmisartan 80 mg treatment, ABPM was repeated. Telmisartan significantly reduced mean systolic blood pressure, diastolic blood pressure (DBP) and pulse pressure compared with previous antihypertensive therapy over each time interval (24-h, morning, night-time and the last 6 h of the dosing interval [2.00 a.m.-8.00 a.m.]) analysed. In addition, more than 90% of patients responded successfully (clinic DBP <90 mmHg or a >10 mmHg reduction in clinic DBP) at the end of telmisartan treatment. In conclusion, telmisartan provides effective blood pressure control throughout the 24-h dosing interval in patients with mild-to-moderate hypertension who were unresponsive to previous antihypertensive medication.

Telmisartan/hydrochlorothiazide: in the treatment of essential hypertension

Oral telmisartan/hydrochlorothiazide (HCTZ) combines two antihypertensive agents, a selective angiotensin II receptor antagonist with a long half-life and once-daily administration, and a thiazide diuretic. In two large, 8-week, double-blind trials, patients with hypertension unresponsive to monotherapy who received combined telmisartan/HCTZ 80/12.5 or 40/12.5 mg/day, achieved significantly larger reductions in diastolic and systolic blood pressure (BP), than recipients of continued telmisartan monotherapy (p < 0.05 for all). Compliance with telmisartan/HCTZ 80/12.5 mg/day was 98.9%. In patients with hypertension, telmisartan/HCTZ resulted in similar BP reductions to oral enalapril/HCTZ and atenolol/HCTZ in 26-week double-blind trials and greater reductions than oral losartan/HCTZ 50/12.5 mg/day in a 6-week randomised open-label trial (p < 0.001). Up to one-third of patients with hypertension initially responsive to telmisartan 40 or 80 mg/day in a 4-year study required the eventual addition of HCTZ 12.5 or 25 mg/day and/or another agent to maintain BP control. BP was controlled in about 75% of these by adding only HCTZ. In clinical trials of up to 4 years, including elderly patients, telmisartan/HCTZ had similar tolerability to placebo, with few reports of hypokalaemia. Most adverse events were mild to moderate.

The telmisartan Programme of Research tO show Telmisartan End-organ proteCTION (PROTECTION) Programme

Angiotensin-II receptor blockers (ARBs) have been shown to provide stroke, cardiac and renal protection in high-risk hypertensive patients. Telmisartan is a powerful and selective ARB that provides sustained blood pressure reduction for a full 24 h after a single dose and continues to protect against circadian blood pressure surges in the critical early morning hours. The objective of the Programme of Research tO show Telmisartan End-organ proteCTION (PROTECTION) is to measure the end-organ protective effects of telmisartan in patients at high risk of renal, cardiac and vascular damage. An extensive series of clinical trials is being conducted to compare telmisartan with valsartan, losartan, amlodipine and ramipril in patients at increased risk of end-organ damage. Nine clinical studies will examine the effects of telmisartan in about 5000 hypertensive patients with isolated systolic hypertension, type 2 diabetes, obesity, left ventricular hypertrophy or renal disease. All of the studies will be conducted using state-of-the-art technology, including such techniques as ambulatory blood pressure monitoring and magnetic resonance imaging. This programme will also investigate the effects of an ARB on key surrogate markers of organ tissue damage. This series of trials will characterize the end-organ protective effects of telmisartan in hypertensive patient populations at high risk of clinical events.

Comparison of telmisartan versus losartan: meta-analysis of titration-to-response studies

OBJECTIVES

To compare the ability of telmisartan and losartan to reduce mean diastolic blood pressure (DBP) during the last 6 h of the 24-h dosing interval in a prospectively planned meta-analysis of ambulatory blood pressure monitoring (ABPM) data from two independent studies.

METHODS

Data were from two independent randomized, double-blind, double-dummy, titration-to-response studies conducted in patients with mild-to-moderate hypertension (seated cuff DBP 95-109 mmHg, 24-h mean ambulatory DBP >or=85 mmHg). After a 4-week placebo run-in period, patients received once-daily telmisartan 40 mg or losartan 50 mg, with up-titration after 4 weeks to telmisartan 80 mg or losartan 100 mg, respectively, if seated trough cuff DBP >or=90 mmHg. Blood pressures were recorded using ABPM immediately before randomization and after 8 weeks of active treatment. In addition, seated trough cuff blood pressures were measured at baseline and after 4 and 8 weeks of active treatment.

RESULTS

Titration to the higher dose was required in 60.1% of telmisartan patients and 69.5% of losartan patients (P=0.01). Reductions from baseline in the last 6 h mean ambulatory DBP with telmisartan and losartan were 6.6+/-0.4 and 5.1+/-0.4 mmHg, respectively (P<0.01, adjusted for baseline and study); the effects were homogeneous across the two studies. During the last 6 h of the 24-h dosing interval, telmisartan produced greater reductions in each of the observed hourly mean ambulatory DBP values. Telmisartan-induced reductions were also greater for the majority of the observed hourly mean ambulatory DBP values over the entire 24-h dosing interval. Reductions from baseline in the last 6 h adjusted mean ambulatory systolic blood pressure (SBP) for telmisartan and losartan were 9.9+/-0.6 and 7.8+/-0.6 mmHg, respectively (P=0.01). The 24-h profiles of ambulatory SBP hourly mean reductions were similar to those for DBP. Both telmisartan and losartan were found to be safe and well tolerated.

CONCLUSIONS

Telmisartan 40/80 mg is superior to losartan 50/100 mg in controlling DBP and SBP during the last 6 h of the 24-h dosing interval.

Angiotensin II receptor blockade: is there truly a benefit of adding an ACE inhibitor?

We assessed the blockade of the renin-angiotensin system (RAS) achieved with 2 angiotensin (Ang) antagonists given either alone at different doses or with an ACE inhibitor. First, 20 normotensive subjects were randomly assigned to 100 mg OD losartan (LOS) or 80 mg OD telmisartan (TEL) for 1 week; during another week, the same doses of LOS and TEL were combined with 20 mg OD lisinopril. Then, 10 subjects were randomly assigned to 200 mg OD LOS and 160 mg OD TEL for 1 week and 100 mg BID LOS and 80 mg BID TEL during the second week. Blockade of the RAS was evaluated with the inhibition of the pressor effect of exogenous Ang I, an ex vivo receptor assay, and the changes in plasma Ang II. Trough blood pressure response to Ang I was blocked by 35+/-16% (mean+/-SD) with 100 mg OD LOS and by 36+/-13% with 80 mg OD TEL. When combined with lisinopril, blockade was 76+/-7% with LOS and 79+/-9% with TEL. With 200 mg OD LOS, trough blockade was 54+/-14%, but with 100 mg BID it increased to 77+/-8% (P<0.01). Telmisartan (160 mg OD and 80 mg BID) produced a comparable effect. Thus, at their maximal recommended doses, neither LOS nor TEL blocks the RAS for 24 hours; hence, the addition of an ACE inhibitor provides an additional blockade. A 24-hour blockade can be achieved with an angiotensin antagonist alone, provided higher doses or a BID regimen is used.