An Evaluation of the Effect of an Angiotensin-converting Enzyme (ACE) Inhibitor on the Growth Rate of Small Abdominal Aortic Aneurysms.
Phase: PHASE2
Conditions: Abdominal Aortic Aneurysm
Sponsor: Imperial College London

AARDVARK 
Short summary 
final version 1
 
 
29/07/2010 
Title: An evaluation of the effect of an angiotensin-converting enzyme 
(ACE) inhibitor on the growth rate of small abdominal aortic aneurysms 
 
AARDVARK Aortic Aneurysmal Regression of Dilation : Value of Ace-inhibition on Ris K  
 
Objectives:  
1.  To investigate the hypothesis that an ACE-inhibitor reduces abdominal aortic aneurysm 
(AAA) growth rate. In a pilot 3-arm randomised controlled trial: The three interventions are 
ACE-inhibition with perindopril versus equivalent blood pressure reduction with amlodipine (a 
calcium channel blocker) versus placebo. By comparing the effects in the perindopril and 
amlodipine arms, this design will permit an evaluation of any blood pressure independent 
effects of perindopril. 
2.  Pending results of the pilot trial, to work with the local and National Aneurysm Screening 
programme to conduct a larger, definitive 3-arm randomised controlled trial, to investigate 
the hypothesis that blood pressure reduction with an ACE-inhibitor slows the rate of small 
AAA growth preferentially compared with other antihypertensive agents.  Aneurysm-related 
mortality, morbidity and quality of life will be the major secondary end-points. 
 
The pilot trial will recruit approximately 225 patients from aortic aneurysm screening sites in 
or near to London.  They will be seen and assessed with an ultrasound examination every 
three months for a period of 24 months. 
 
(i) 
Inclusion criteria 
(ii) 
All men or women, aged OVER 60 years, with AAA between 3.0 and 5.5 cm and 
with a systolic BP <150mmHg will be eligible for inclusion in the trial unless they 
are routinely already receiving an ACE-inhibitor or amlodipine 10mg daily. For 
patients whose systolic BP is >150mmHg, a 6 week course of the diuretic 
indapamide SR (1.5mg daily) will be given, with re-evaluation of  BP in the 6th 
week:  If the SBP falls to <150mmHg on this medication subjects would then be 
eligible for inclusion into the study. If this diuretic treatment is not appropriate 
then 5mgs of amlodipine could be prescribed by the patients GP if not already 
taking this drug.  This would be followed by a six week re-evaluation as above. 
. 
(ii) 
Exclusion criteria  
 
1. 
Patients who cannot be converted to diuretic therapy and/or lower doses of amlodipine 
or patients already taking an angiotensin II antagonist (ARB) for the treatment of blood 
pressue. 
2. 
those with known renal artery stenosis (>50%), or with a serum creatinine > 180umol/L 
on routine testing. 
3. 
those unable to give informed consent   
4. 
those too frail to travel for 3-monthly surveillance will be excluded. 
5. 
Any clinically significant medical condition which, in the opinion of the investigator, 
may interfere with the study results; 
6. 
Participation in another trial of an investigational product or device within the previous 
30 days; 
7. 
Known allergy or sensitivity to perindopril or amlodipine 
8. 
Unable or unwilling to comply with the requirements of the study, in the opinion of the 
investigator. 
 

AARDVARK 
Short summary 
final version 1
 
 
29/07/2010 
 
Project Timetable and Milestones 
 
   Set up  
 
Recruitment 
 
         =24 months   
      
Close out 
┴────────┴─────────────┴──────────────────┴────────┴ 
 0 
 
6 
 
 
18 
 
 
 
36 
 
42 
 
 
 
Total trial length = 42 months. 
 
 
 
 
 
Local sceening  
centre staff   
Screen & 
Consent 
Project co-
ordinator 
And medical 
investigator 
 
Randomisation 
Project co-ordinator 
 
Treatment 
Project co-ordinator 
 
 
 
Visit  
-2 
Suitable 
patients 
identified and 
contacted 
-1 
 
AAA 3.0-5.4cm? 
SBP<150mmHg
? 
 
1 
(Baseline) 
Either 1 week after blood 
test or 6 weeks after starting 
indapamide 
2 
3 
4 
5 
6 
7 
8 
9 
Months 
 
-2 to 0.25 
0 
3 
6 
9 
12 
15 
18 
21 
24 
Inclusion & 
exclusion 
criteria  
 
X 
check 
 
 
 
 
 
 
 
 
 Informed 
consent 
 
X 
check 
 
 
 
 
 
 
 
 
Demography 
 
X 
 
 
 
 
 
 
 
 
 
Past medical 
history  
 
X 
 
 
 
 
 
 
 
 
 
Current medical 
therapies 
 
X 
check 
X 
X 
X 
X 
X 
X 
X 
X 
Ultrasound of 
AAA 
AAA 3.0-5.4cm? 
 
review 
X 
 
X 
X 
X 
X 
X 
X 
X 
X 
Blood pressure 
 
X 
X 
X 
X 
X 
X 
X 
X 
X 
X 
Adverse events 
 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
Pill count 
 
 
 
X 
X 
X 
X 
X 
X 
X 
X 
Blood for 
creatinine and 
electrolytes 
 
X 
review 
X 
 
 
X 
 
 
 
X 
Blood for lipid 
profile 
 
X 
review 
check lipid lowing 
prescribed 
 
 
 
 
 
 
 
 
 
EuroQoL, health 
resource 
questionnaire 
 
 
 
 
 
 
X 
 
 
 
X 
Time  
(months) 
          ↑ 
Start of trial 
          ↑ 
End of trial