Additional identifiers
EudraCT number
2008-005432-32
ClinicalTrials.gov number
Protocol/serial number
6830
Study information
Scientific title
Effects of an angiotensin receptor antagonist candesartan versus a calcium channel blocker amlodipine on microvascular rarefaction, endothelial dysfunction, and microalbuminuria in essential hypertension
Acronym
CAMIRA
Study hypothesis
Many abnormalities are known to occur in the microcirculation in essential hypertension including reduction in vascular density or rarefaction. Capillary rarefaction is not confined to the skin but represents a widespread phenomenon affecting several tissues in hypertensive individuals including the myocardium, the kidneys and the brain resulting in reducing coronary blood flow reserve, and precipitating heart failure in cardiac hypertrophy. In this study we aim to investigate, in a double-blind randomised design, the effects of treating hypertension with an angiotensin receptor blocker versus a calcium antagonist on the reversibility of capillary rarefaction.
On 19/11/2013 the anticipated end date was changed from 01/10/2011 to 01/10/2014.
Ethics approval
London-Surrey Borders Research Ethics Committee, 19/11/2008, ref: 08/H0806/72
Study design
Single centre randomised interventional treatment trial
Primary study design
Interventional
Secondary study design
Randomised controlled trial
Trial setting
GP practices
Trial type
Treatment
Patient information sheet
Not available in web format, please use the contact details below to request a patient information sheet
Condition
Topic: Cardiovascular; Subtopic: Cardiovascular (all Subtopics); Disease: Cardiovascular
Intervention
After a 2-week single-blind placebo run-in period, patients will be randomised to 8 weeks treatment with either candesartan 8 mg once daily orally (with forced titration to 16 mg once daily orally after 2 weeks) or amlodpine 5 mg once daily orally (with forced titration to 10 mg once daily orally after 2 wks).
Study entry: single randomisation only
Intervention type
Drug
Phase
Phase IV
Drug names
Candesartan, amlodipine
Primary outcome measures
The increase in maximal capillary density at the end of 8 weeks treatment.
Secondary outcome measures
1. Change in aortic augmentation index at 8 weeks
2. Change in basal capillary density at 8 weeks
3. Reduction in microalbuminuria at 8 weeks
4. Improvement in pulse wave velocity at 8 weeks
Overall trial start date
01/02/2010
Overall trial end date
01/10/2014
Reason abandoned
Eligibility
Participant inclusion criteria
1. Male and female, aged 18 years or older
2. Uncomplicated mild-to-moderate essential hypertension, i.e., sitting diastolic blood pressure (BP) greater than or equal to 90 to less than 110 mmHg and/or systolic BP greater than or equal to 140 to less than 180 mmHg)
3. Not previously treated for their high blood pressure
4. Caucasian and light-coloured Asians only, this is due to the technical difficulty of performing capillaroscopy in dark-skinned individuals
Participant type
Patient
Age group
Adult
Gender
Both
Target number of participants
Planned sample size: 46
Participant exclusion criteria
1. Malignant or accelerated hypertension
2. Serum creatinine greater than 180 µmol/L
3. Ischaemic heart disease
4. Cerebrovascular disease
5. Impaired liver functions
6. Diabetes mellitus
7. Pregnancy or risk of pregnancy
8. Lactation
9. History of alcoholism, drug abuse or other problems that are likely to invalidate the informed consent
10. Dark-skinned individuals (capillary microscopy can't be performed)
Recruitment start date
01/02/2010
Recruitment end date
01/10/2014
Locations
Countries of recruitment
United Kingdom
Trial participating centre
Blood Presure Unit
Blood Presure Unit
St George's University
Cranmer Terrace
London
SW17 0RE
United Kingdom
Sponsor information
Organisation
St George's, University of London (UK)
Sponsor details
Cranmer Terrace
London
SW17 0RE
United Kingdom
Sponsor type
University/education
Website
Funders
Funder type
Industry
Funder name
Takeda UK Limited (UK)
Alternative name(s)
Funding Body Type
Funding Body Subtype
Location
Results and Publications
Publication and dissemination plan
Not provided at time of registration
Intention to publish date
Participant level data
Not provided at time of registration
Results - basic reporting
Publication summary