APEX Study: Effects of Allopurinol on Coronary and Peripheral Endothelial Function in Patients With Cardiac Syndrome X (APEX)

This study has been completed.
Information provided by:
University of Dundee
ClinicalTrials.gov Identifier:
First received: August 6, 2007
Last updated: June 25, 2010
Last verified: February 2009
Morbidity of patients with cardiac syndrome X (typical anginal-like chest pain and normal coronary arteriograms) is high with continuing episodes of chest pain and frequent hospital readmissions. Management of this syndrome represents a major challenge to the treating physician. Evidence for the important role of endothelial dysfunction and oxidative stress in the pathogenesis of cardiac syndrome X has been recently strengthened by the finding that basal superoxide production predicts future cardiovascular events in this patient group. The investigators have recently shown that high-dose allopurinol abolishes vascular oxidative stress and improves endothelial function in patients with chronic heart failure, which makes allopurinol a prime candidate to reduce oxidative stress in syndrome X. The hypothesis to be tested in this study is whether allopurinol offers dual benefits of improving vascular function and reducing myocardial ischaemia in patients with cardiac syndrome X. This study may discover a novel way to improve endothelial function and anginal symptoms which are often debilitating in these patients.

Condition Intervention Phase
Syndrome X
Drug: allopurinol
Drug: placebo
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Endpoint Classification: Efficacy Study
Intervention Model: Crossover Assignment
Masking: Double Blind (Subject, Investigator)
Primary Purpose: Treatment
Official Title: APEX Study: Effects of Allopurinol on Coronary and Peripheral Endothelial Function in Patients With Cardiac Syndrome X

Resource links provided by NLM:

Further study details as provided by University of Dundee:

Primary Outcome Measures:
  • The primary objective of this study is to investigate the effects of allopurinol on coronary and peripheral microvascular and endothelial function in patients with cardiac syndrome X [ Time Frame: 3-5 years ] [ Designated as safety issue: Yes ]

Secondary Outcome Measures:
  • The secondary objectives of this study are to assess the effects of allopurinol on chest pain incidence, maximal ST-segment depression and Duke's score [ Time Frame: 3- 5years ] [ Designated as safety issue: Yes ]

Estimated Enrollment: 40
Study Start Date: June 2008
Study Completion Date: June 2010
Primary Completion Date: June 2010 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: 1 Drug: allopurinol
allopurinol 300mg twice a day
Placebo Comparator: 2 Drug: placebo


Ages Eligible for Study:   18 Years to 75 Years
Genders Eligible for Study:   Both
Accepts Healthy Volunteers:   Yes

Inclusion Criteria:

  • Typical history of angina
  • Positive exercise treadmill test and normal coronary angiogram

Exclusion Criteria:

  • Significant valvular heart disease or left ventricular hypertrophy
  • Age <18 years
  Contacts and Locations
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Please refer to this study by its ClinicalTrials.gov identifier: NCT00512057

United Kingdom
University of Dundee
Dundee, United Kingdom, dd1 3sy
Sponsors and Collaborators
University of Dundee
Principal Investigator: Chim Lang University of Dundee
  More Information

No publications provided

Responsible Party: Chim Lang, University of Dundee
ClinicalTrials.gov Identifier: NCT00512057     History of Changes
Other Study ID Numbers: apex001 version6 
Study First Received: August 6, 2007
Last Updated: June 25, 2010
Health Authority: United Kingdom: Research Ethics Committee
United Kingdom: Medicines and Healthcare Products Regulatory Agency

Keywords provided by University of Dundee:
cardiac syndrome X
endothelial function

Additional relevant MeSH terms:
Microvascular Angina
Angina Pectoris
Cardiovascular Diseases
Heart Diseases
Myocardial Ischemia
Pathologic Processes
Vascular Diseases
Antirheumatic Agents
Enzyme Inhibitors
Free Radical Scavengers
Gout Suppressants
Molecular Mechanisms of Pharmacological Action
Pharmacologic Actions
Physiological Effects of Drugs
Protective Agents
Therapeutic Uses

ClinicalTrials.gov processed this record on February 11, 2016