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Original article 1641

Circulating angiopoietin-2 in e

ssential hypertension: relationto atherosclerosis, vascular inflammation, and treatment witholmesartan/pravastatinSascha Davida, Philipp Kumpersa, Alexander Lukasza, Jan T. Kielsteina,Hermann Hallera and Danilo Fliserb

Background Endothelial activation has emerged as an

early event in the pathogenesis of cardiovascular disease.

Angiopoietin-2 (Ang-2) has been identified as a

nonredundant endothelial-specific facilitator of vascular

responsiveness to inflammatory stimuli. We have earlier

shown that angiotensin II receptor blocker (ARB) reduces

mediators of vascular inflammation in hypertension and

cardiovascular disease. We aimed at studying the effect of

ARB and/or 3-hydroxy-3-methyl-glutaryl-CoA blockade on

Ang-2 and the association between vascular inflammation

markers and Ang-2 levels in hypertensive patients.

Methods We assessed a panel of vascular inflammation

markers and Ang-2 during 12 weeks of therapy with the ARB

olmesartan (n U 94) or placebo (n U 96) in a prospective,

double-blind, multicenter study in patients with essential

hypertension (re-evaluation of the European Trial on

Olmesartan and Pravastatin in Inflammation blood

samples). Pravastatin was added to the double-blind

therapy at week 6 in both arms. The association of

demographic variables and inflammation markers with

Ang-2 has been investigated.

Results Initial Ang-2 concentrations in the study population

were elevated compared with healthy controls (4.23 W 3.1

versus 0.88 W 0.43 ng/ml; P < 0.0001). Ang-2 was higher in

the elderly (P U 0.01), women (P < 0.001), and in the

presence of atherosclerosis (P U 0.02). Ang-2 correlated

significantly with soluble TEK tyrosine kinase-2, interleukin-

6, vascular cell adhesion molecule-1, and inter-cellular

adhesion molecule-1. Surprisingly, neither monotherapy

with olmesartan or pravastatin nor the combination therapy

affected Ang-2 concentrations.

opyright © Lippincott Williams & Wilkins. Unauth

0263-6352 � 2009 Wolters Kluwer Health | Lippincott Williams & Wilkins

Conclusion Ang-2 concentrations are elevated in

hypertensive patients, particularly those with

atherosclerosis, possibly reflecting pronounced endothelial

activation. ARBs effectively decreased several inflammatory

mediators, but did not affect vascular responsiveness in an

Ang-2-dependent manner. Elevated Ang-2 levels in

hypertensive patients correlate with adhesion molecules.

J Hypertens 27:1641–1647 Q 2009 Wolters Kluwer Health |

Lippincott Williams & Wilkins.

Journal of Hypertension 2009, 27:1641–1647

Keywords: angiopoietin-2, angiotensin II receptor blocker, arterialhypertension, atherosclerosis, 3-hydroxy-3-methyl-glutaryl-CoA reductaseinhibitor, inter-cellular adhesion molecule-1, inflammation markers,olmesartan, statin, vascular cell adhesion molecule-1

Abbreviations: Ang-1, angiopoietin-1; Ang-2, angiopoietin-2; ARB,angiotensin II receptor blocker; CKD, chronic kidney disease; CVD,cardiovascular disease; HCTZ, hydrochlorothiazide; hsCRP, high-sensitiveC-reactive protein; ICAM-1, inter-cellular adhesion molecule 1; IFN g, interferong; MCP-1, macrophage chemotactic protein-1; PI3K, phosphatidylinositol3-kinase; RTKs, receptor tyrosine kinases; TNF-a, tumor necrosis factor-a;VCAM-1, vascular cell adhesion molecule 1; WPB, Weibel–Palade bodies

aDepartment of Medicine, Division of Nephrology and Hypertension, MedicalSchool Hanover, Hanover and bUniversity of Saarland, Homburg/Saar, Germany

Correspondence to Sascha David, MD, Department of Medicine, Division ofNephrology, Medical School Hanover, Carl-Neuberg-Strasse 1, 30625 Hanover,GermanyTel: +49 511 532 6319; fax: +49 511 55 23 66;e-mail: david.sascha@mh-hannover.de

Part of this work was presented in abstract form at last year’s congress of theAmerican Society of Nephrology (J Am Soc Nephrol 2008; 19 Suppl abstract no.626A).

Received 3 December 2008 Revised 11 March 2009Accepted 20 March 2009

See editorial commentary on page 1524

IntroductionAtherosclerosis is an inflammatory process that selec-

tively affects arteries and that is present in a variety of

conditions such as hypertension and diabetes mellitus

[1–5]. Thrombo-occlusive complications of atherosclero-

sis, including stroke and myocardial infarction, are major

causes of morbidity and mortality [6]. Circulating

immune cells that attach to the inflamed vessels by

interacting with adhesion molecules and chemokines

secreted by the activated endothelium play a pivotal role

in atherogenesis [7]. In this process, the activational state

of the endothelial layer is a major determinate for the

initiation, localization, extent, and propagation of inflam-

matory damage. Endothelial activation, in general, is

characterized by phenotypic changes from a quiescent,

unresponsive to a responsive state. This process is associ-

ated with increased expression of luminal adhesion mol-

ecules [e.g. inter-cellular adhesion molecule (ICAM) and

vascular cell adhesion molecule (VCAM)], leukocyte

recruitment, and induction of inflammatory gene tran-

scription [8,9].

Angiopoietin-1 (Ang-1) and angiopoietin-2 (Ang-2) are

antagonistic ligands of the TEK tyrosine kinase-2 (Tie2)

orized reproduction of this article is prohibited.

DOI:10.1097/HJH.0b013e32832be575

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1642 Journal of Hypertension 2009, Vol 27 No 8

receptor, the second class of vascular-specific receptor

tyrosine kinases (RTKs) [10], the vascular endothelial

growth factor (VEGF) receptor being the first. The Ang–

Tie ligand–receptor has been shown to tightly control

endothelial activation [10,11]. Ang-1, mainly produced by

pericytes and vascular smooth muscle cells, preserves

vessel integrity and promotes anti-inflammatory effects

by activation of the phosphatidylinositol 3-kinase (PI3K)/

Akt pathway [12]. Further, interaction of active Tie2 with

the adaptor protein A20-binding inhibitor of nuclear

factor kappa-light-chain-enhancer of activated B cells

(NF-kappa B) 2 (ABIN2) blocks NF-kB-mediated

expression of inflammatory genes such as those encoding

VCAM-1 and ICAM-1 and counteracts eventual signals

by small amounts of tumor necrosis factor-a (TNF-a)

[13]. In contrast, Ang-2 operates as a counterbalance to

Ang-1 by inhibiting Ang-1 binding to Tie2, followed by

induction of inflammatory gene expression and leukocyte

recruitment [10]. Ang-2 is stored and rapidly released

from endothelial Weibel–Palade bodies (WPB) upon

stimulation by proinflammatory stimuli, thus initiating

rapid vascular responses [14].

Elevated concentrations of Ang-2 have been reported

under various conditions with endothelial activation, for

example, sepsis [15], diabetes mellitus [16], cardiac allo-

graft arteriosclerosis [17], essential hypertension [18,19],

vasculitis [20], chronic kidney disease (CKD) [21], acute

coronary syndrome [22], and hematological malignancies

[23].

Anti-inflammatory properties of angiotensin II receptor

1 blockers (ARB1) have been demonstrated in various

experimental and clinical trials [24–28], but the underlying

mechanisms are currently not completely understood.

Furthermore, 3-hydroxy-3-methyl-glutaryl (HMG)-CoA

reductase inhibitors (statins) have been found to promote

anti-inflammatory effects on the endothelium indepen-

dently from their lipid-lowering effects in endothelial cell

cultureexperiments [29–32]. Intriguingly, statintreatment

might also prevent the exocytosis of WPBs in patients

[33].

Transferring these experimental data from bench to

bedside, we hypothesize the beneficial effect of ARB

and statin treatment on circulating Ang-2 levels

in hypertensive patients. We, therefore, re-evaluated

circulating Ang-2 levels in plasma samples from the

European Trial on Olmesartan and Pravastatin in Inflam-

mation (EUTOPIA) [34]. We investigated the effect of

ARB and/or HMG-CoA blockade on Ang-2 concen-

trations and the association of circulating Ang-2 with a

panel of inflammation markers [TNF-a, interleukin-6

(IL-6), VCAM-1, ICAM-1, macrophage chemotactic

protein-1 (MCP-1), and high-sensitive C-reactive protein

(hsCRP)] in hypertensive patients with manifest athero-

sclerosis.

opyright © Lippincott Williams & Wilkins. Unautho

Patients and methodsPatientsThis study is a re-evaluation of blood samples from the

EUTOPIA trial [34]. The present phase IIIb trial was a

randomized, placebo-controlled, double-blind, parallel-

group study conducted between July 2001 and July 2003

at 26 investigator sites in Germany, Poland, and the

Czech Republic. Inclusion and exclusion criteria are

described elsewhere [34]. In brief, eligible for inclusion

were male and female adults with essential hypertension,

any diagnosed atherosclerotic disease (i.e. coronary or

peripheral artery disease), type 2 diabetes mellitus, and/

or low-density lipoprotein (LDL) cholesterol serum con-

centration between 3.89 and 6.48 mmol/l. Patients must

have had an hsCRP serum concentration of less than

3 mg/l. Exclusion criteria were any type of secondary

hypertension, serum creatinine of more than 150 mmol/

l, and/or proteinuria of more than 100 mg/dl, any other

type of acute or chronic inflammatory disease, and/or an

hsCRP serum concentration of more than 20 mg/l.

Furthermore, patients with sitting DBP of more than

110 mmHg or sitting SBP of more than 200 mmHg,

patients who had taken any statins within 3 months

before screening, and patients with significantly elevated

liver enzyme levels were excluded.

Protocol and measurementsAfter a taper-off period of 2 weeks for pretreated patients

and an obligatory 2-week placebo run-in phase for all

patients, those who were eligible for the trial were

randomized to one of the two treatment groups receiving

either 20 mg olmesartan or olmesartan-matching placebo

once daily in the morning. Patients with no reasonable

response to treatment, that is, sitting DBP of more than

90 mmHg, additionally received either 12.5 or 25 mg

hydrochlorothiazide (HCTZ). After week 6 of double-

blind medication, all patients received 20 mg pravastatin

once daily (in the evening at bedtime) as an add-on to the

double-blind treatment. During the study, patients were

not allowed to receive any other antihypertensive drugs,

other lipid-lowering agents, tricyclic antidepressants, or

long-acting nitrates.

Plasma samples were collected at baseline (i.e. after the

placebo run-in period) and after 6 and 12 weeks of

treatment, centrifuged, immediately placed on ice,

and stored at �808C until inflammation markers were

measured in the laboratory of the Division of Nephrol-

ogy, Medical School Hanover. Plasma concentration of

hsCRP was measured with a clinically validated high-

sensitivity nephelometric assay (Dade Behring; Siemens

Healthcare Diagnostics Ltd., Deerfield, Illinois, USA)

[35]. Plasma concentrations of Ang-2, serum soluble Tie-

2 (sTie-2), TNF-a, IL-6, MCP-1, and ICAM-1 were

measured with an ELISA according to the manufacturer’s

instructions (R&D Systems, Minneapolis, Minnesota,

USA). The intraassay coefficients of variation for these

rized reproduction of this article is prohibited.

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Angiopoietin-2 in hypertensive patients David et al. 1643

Table 1 Demographic data and angiopoietin-2 level of patients with essential hypertension treated with olmesartan or placebo at baseline

Total Olmesartan Placebo P

Number of patients, n 190 94 96Sex, n 0.66 (NS)

Male 94 45 49Female 96 49 47

Age (years) 57.0 58�9.6 58.3�8.5 0.95 (NS)BMI (kg/m2) 29.7�4.7 29.9�4.8 29.5�4.8 0.40 (NS)Sitting SBP (mmHg) 159�9 158�9 159�9 0.90 (NS)Sitting DBP (mmHg) 100�3 100�3 100�3 0.96 (NS)Necessity of taper-off antihypertensive drugs, n 132 65 67Aspirin therapy, n 69 31 38Atherosclerotic disease, n 0.23 (NS)

No 57 32 25Yes 133 62 71

Diabetes mellitus, n 0.04No 174 90 84Yes 16 4 12

Hypercholesterolemia, n 0.65 (NS)No 84 40 44Yes 106 54 52

Angiopoietin-2 (ng/ml)Baseline 3.33 3.15 3.46 0.91 (NS)Week 6 3.40 3.49 3.31 0.92 (NS)Week 12 3.53 3.34 3.80 0.45 (NS)

NS, not significant.

tests ranged between 4.9 and 6.8%, respectively. The

limits of detection for the different assays were hsCRP

(Dade Behring) 0.02 mg/l, TNF-a (R&D Systems)

0.5 ng/well, IL-6 (R&D Systems) 0.15 ng/well, VCMA-

1 (R&D Systems) 0.3 ng/well, ICAM-1 (R&D Systems)

0.2 ng/well, and for MCP-1 (R&D Systems) 3.1 ng/well.

To eliminate interassay variability, all samples from one

patient were tested in a single assay.

Statistical analysisTo compare demographic and laboratory parameters

between treatment groups at baseline, we used the x2

test for categorical variables (e.g. sex) and the Wilcoxon

rank-sum test for continuous variables (e.g. age). Uni-

variate analyses of Ang-2 and Ang-2 change between the

relevant visits were based on nonparametric methods,

especially the Wilcoxon rank-sum test for the comparison

between two groups and the Kruskal–Wallis test for the

comparison between several groups/levels. Analysis of

covariance (ANCOVA) was used to model Ang-2 at base-

line and Ang-2 changes between visits as a function of

multiple factors simultaneously; effects were estimated

and tested after adjustment for the influence of the other

factors in the model; for the purpose of this modeling,

Ang-2 was log-transformed as indicated by the distri-

bution of the individual data. All statistical tests were

two-sided with a 5% level of statistical significance. Data

are presented as median and quartiles or mean�SD

dependent on their distribution.

ResultsFor this re-evaluation of the EUTOPIA trial, 190 of the

original 199 blood samples were eligible. Thus, the final

full analysis set comprised 190 patients, of whom 94 were

opyright © Lippincott Williams & Wilkins. Unauth

treated with olmesartan and 96 were in the placebo

treatment group. A post-hoc power analysis revealed that

with this size of the study population, the power to detect

a statistically significant difference in Ang-2 levels of

1 ng/ml (e.g. 4.0 versus 3.0 ng/ml; SD 1.5 ng/ml) would

be close to 100% (0.995). The demographic data of these

patients at baseline are presented in Table 1. Both

treatment groups were not different with regard to age,

sex, and BMI, but the placebo treatment group com-

prised significantly more patients with known type 2

diabetes mellitus.

Mean Ang-2 concentration in the total study population

(n¼ 190) was significantly elevated compared with healthy

controls (n¼ 28) (4.23� 3.1 versus 0.88� 0.43 ng/ml;

P< 0.0001, Fig. 1a), and baseline Ang-2 levels did not

differ between treatment groups (olmesartan versus

placebo). In contrast to this finding, the soluble Ang-2

receptor sTie-2 was significantly lower in the study

population (0.53� 0.22 ng/ml) compared with healthy

controls (3.04� 0.43 ng/ml; P< 0.0001). The baseline

Ang-2 values for treatment and placebo group and

all dependent variables are shown in Table 2. Ang-2 at

baseline primarily depended on sex and age, so that

median Ang-2 levels were significantly elevated in

female compared with male patients (, 3.98 versus <2.78 ng/ml; P< 0.001, Fig. 1b).

According to patients’ age, all study participants have

been grouped into one of the following classes: young

(<45 years), middle-aged (45–65 years), elderly (65–75

years), and very elderly (>75 years). A statistically sig-

nificant increase of Ang-2 level dependent on patients’

age class has been detected (P¼ 0.01).

orized reproduction of this article is prohibited.

Copyright © Lippincott Williams & Wilkins. Unautho

1644 Journal of Hypertension 2009, Vol 27 No 8

Fig. 1

Box and whisker plots of circulating baseline angiopoietin-2 (a) inpatients with arterial hypertension (n¼190) and in normotensivehealthy controls (n¼28), (b) by sex (P<0.001), and (c) by presence ofatherosclerosis (P¼0.02). Ang-2, angiopoietin-2; AS, atherosclerosis.

Table 2 Baseline angiopoietin-2 level of hypertensive patientsdivided into subgroups dependent on treatment, sex, age, andconcomitant disease

(n¼190)Baseline Ang-2

(ng/ml)P (Wilcoxon

test)

Treatment 0.91Olmesartan 94 3.15 (2.36–5.08)Placebo 96 3.46 (2.40–4.89)

Sex 0.0004Male 94 2.78 (2.21–4.29)Female 96 3.98 (2.72–5.70)

Age class 0.012Young 12 2.84 (2.24–4.23)Middle-aged 130 3.19 (2.37–4.94)Elderly 44 4.12 (2.32–4.96)Very elderly 4 9.68 (8.48–10.74)

Atherosclerotic disease 0.022No 57 2.84 (2.21–4.30)Yes 133 3.60 (2.47–5.14)

Diabetes mellitus 0.515No 174 3.28 (2.33–5.00)Yes 16 3.64 (2.73–4.99)

Data expressed as median (interquartile range). Ang-2, angiopoietin-2.

On the basis of the nonparametric Wilcoxon rank-sum

test, median Ang-2 was significantly higher in patients

with atherosclerosis (atherosclerosis: 3.60 ng/ml versus no

atherosclerosis: 2.84 ng/ml; P¼ 0.02, Fig. 1c). For patients

with diabetes mellitus, Ang-2 levels were slightly

increased but not at a statistically significant level (dia-

betes mellitus: 3.64 ng/ml versus no diabetes mellitus:

3.28 ng/ml; P¼ 0.52). This lack of statistical significance

may be due to the small number of diabetic patients (only

16 of 190).

From the EUTOPIA trial results, we knew a significant

decrease for hsCRP (�15.1%; P< 0.05), TNF-a (�8.9%;

P< 0.02), and IL-6 (�14.0%; P< 0.05) after 6 weeks of

treatment with olmesartan but not with placebo [34]. With

the addition of pravastatin to the placebo treatment arm,

hsCRP was reported to decrease by 8.0% (not significant).

However, neither olmesartan monotherapy nor cotherapy

with statins resulted in a significant change of Ang-2 serum

levels compared with the placebo group (olmesartan

group: Ang-2 change from baseline to week 6, 0.011 ng/

ml; from week 6 to 12,�0.149 ng/ml; placebo group: Ang-2

change from baseline to week 6, 0.205 ng/ml, P¼ 0.59;

from week 6 to 12, 0.036 ng/ml, P¼ 0.591 for the difference

in change from baseline to week 6 and P¼ 0.467 for the

difference in change from week 6 to week 12 between the

two groups). In addition, pravastatin alone (i.e. cotherapy

with placebo) also did not reduce Ang-2. Table 1 presents

the median Ang-2 values at different time-points.

The mean arterial pressure (MAP) significantly fell in

both the olmesartan (baseline: 119� 5 mmHg, week 6:

104� 10 mmHg, week 12: 102� 8 mmHg) and the

placebo groups (baseline: 120� 5 mmHg, week 6:

109� 10 mmHg, week 12: 104� 9 mmHg).

Ang-2 correlated significantly with its soluble receptor

sTie-2 (r¼ 0.378, P< 0.0001) and with markers of vascular

rized reproduction of this article is prohibited.

Copyright © Lippincott Williams & Wilkins. Unauth

Angiopoietin-2 in hypertensive patients David et al. 1645

Fig. 2

Scatter plots of pairwise correlation of angiopoietin-2 with multiplemarkers of vascular inflammation detected (a) vascular adhesionmolecule 1 (r¼0.2817; P<0.0001), (b) intercellular adhesionmolecule 1 (r¼0.1672; P¼0.02), and (c) interleukin-6 (r¼0.3327;

inflammation such as VCAM-1 (627.9� 193 ng/ml,

r¼ 0.2817; P< 0.0001), ICAM-1 (256.5� 69.7 ng/ml,

r¼ 0.1672; P¼ 0.02), and IL-6 (3.61� 2.96 pg/ml,

r¼ 0.3327; P< 0.0001) (Fig. 2a–c), whereas interferon

g (IFN g) (r¼ 0.0615, P¼ 0.4), MCP-1 (r¼ 0.0805,

P¼ 0.27), hsCRP (r¼ 0.1075, P¼ 0.15), and TNF-a

(r¼ 0.0102, P¼ 0.88) were not associated with Ang-

2 levels.

Blood pressure significantly decreased in both treatment

groups, with a more distinct decrease observed with

olmesartan. The differences between baseline and after

6, 12 weeks were statistically significant. We did not find a

correlation between Ang-2 level and SBP (P¼ 0.68) or

DBP (P¼ 0.68).

DiscussionThe present study is the first clinical investigation on the

influence of the ARB subtype 1 olmesartan medoxomil

and/or the HMG-CoA inhibitor pravastatin on circulating

Ang-2 levels in a large cohort of patients with essential

hypertension. The pertinent findings are: hypertensive

patients with known endothelial activation have signifi-

cantly higher levels of serum Ang-2 than healthy controls;

patients with hypertension and manifest atherosclerosis

have even higher Ang-2 levels than those without signs of

atherosclerosis; these high levels of Ang-2 correlated with

inflammation and adhesion molecules (i.e. IL-6, VCAM-

1, and ICAM-1); and neither ARB monotherapy nor

cotherapy with a statin influenced circulating Ang-

2 levels.

Endothelial cells are known to respond to any kind of

activation by angiogenesis and/or inflammation. The

balance between these two responses is pinned to two

regulators of angiogenesis. Ang-1 dampens the inflam-

matory response and Ang-2 boosts it [10]. A disequili-

brium of the Ang-1/Ang-2 homeostasis in favor of Ang-2

results in a loss of inhibition of the adaptor protein ABIN2

that blocks NF-kB-mediated expression of inflammatory

genes such as those encoding VCAM-1 and ICAM-1

[13,36].

In the present study, the influence of essential hyperten-

sion on circulating Ang-2 level and their association with

inflammation and adhesion molecules have been evalu-

ated. Using a re-evaluation of the EUTOPIA blood

samples, we could prove our hypothesis that arterial

hypertension leads to elevated Ang-2 levels when com-

pared with healthy controls. This finding probably

reflects the endothelial dysfunction leading to permanent

orized reproduction of this article is prohibited.

P<0.0001) as statistically significant. All data are shown as scatterplots with line fitted by simple linear regression. Ang-2, angiopoietin-2;ICAM-1, intercellular adhesion molecule 1; IL-6, interleukin-6; VCAM-1,vascular adhesion molecule 1.

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1646 Journal of Hypertension 2009, Vol 27 No 8

microinflammation and cardiovascular disease. Our result

is well in line with the findings from Nadar et al. [18] who

reported that patients with hypertension have evidence

of changes in plasma angiogenic growth factors that

correlate with the platelet levels of these molecules,

although the interventional effect of ARBs and statins

we focused on in the present work has not been respected

before.

We previously demonstrated the impact of elevated Ang-

2 level to indicate prevalent atherosclerotic burden in

patients with CKD [21]. In the present study, we were

able to confirm our previous results in a larger cohort of

patients with atherosclerosis. The only endogenous

inhibitor of WPB exocytosis is nitric oxide, whose avail-

ability is decreased in CKD. This mechanistic concept of

WPB exocytosis due to a loss of endogenous inhibition

(i.e. nitric oxide) has been discussed to explain acceler-

ated atherosclerosis in CKD. HMG-CoA reductase inhi-

bition has been shown to inhibit WPB exocytosis in

endothelial cell culture experiments [33]. Accordingly,

we hypothesized a lowering effect of statins on WPB-

derived Ang-2 levels in vivo. However, despite promising

experimental results [33], we were not able to demon-

strate such effects in human disease. Neither statin

monotherapy nor cotherapy with an ARB led to a signifi-

cant reduction in Ang-2 level in humans with essential

hypertension.

A second goal of the present study was to identify

whether the anti-inflammatory effects of ARBs represent

Ang-2-dependent processes. With the EUTOPIA study

protocol, we were able to investigate both the effect of

ARB monotherapy and the combination of ARB with

HMG-CoA reductase inhibition. Again, in both settings,

we did not find significant changes in our patients’

elevated Ang-2 levels.

ConclusionCirculating Ang-2 levels are significantly elevated in

hypertensive patients, particularly in those with signs

of atherosclerosis. In addition, Ang-2 levels correlated

with inflammation and adhesion molecules. Despite their

proven in-vivo anti-inflammatory effects, we could not

observe a change in Ang-2 serum levels of patients

treated with an ARB. The results of statin-mediated

inhibition of WPB exocytosis in vitro were also not

confirmed in patients with essential hypertension treated

with pravastatin.

AcknowledgementsThis study was supported by DAIICHI-SANKYO

Pharma and by a European funding ‘Ingenious Hyper-

care’ (LSHM-CT-2006-037093 to Hermann Haller).

The following persons participated as investigators in the

EUTOPIA trial in Poland (in alphabetic order): A.

opyright © Lippincott Williams & Wilkins. Unautho

Doboszynska, J. Gessek, A. Januszewicz, S. Jeka, B.

Kwiatkowska, S. Liszewska-Pfeijfer, F. Monies, S.

Niemczyk, A. Stochmal, A. Wie,cek, A. Witkowski,

and D. Wojciechowski; in the Czech Republic: D. Astl,

R. Cıfkova, Z. Grosman, K. Hrubant, L. Kadlecova, I.

Karen, J. Leso, V. Zemanova, and E. Zıdkova; and in

Germany: K. Buchholz, D. Fliser, H. Haller, A. Hanzlik,

M. Kutemeyer, L. Rehn, and U. Schax.

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