Effect of Amlodipine on Anti-platelet Drug Effect in Patients With Coronary Artery Disease

NCT01203696 | Completed Phase 4

• 1 other identifier: Aml-Clo-protocol-v1
• Study Type: interventional
• Target: 97
• Locations: 1 country
• Sites: 1

Brief Summary

Clopidogrel can reduce risk of cardiovascular disease by inhibiting platelet aggregation. It is metabolized to an active drug by a liver enzyme. Its efficacy may be measured by blood sampling for platelet activity, analyzed by VerifyNow device. Calcium Channel blocker (CCB) is also commonly used for blood pressure and anginal control in these patients. Dihydropyridine group of calcium channel blocker (e.g. amlodipine) inhibits this enzyme. There are observational studies reporting dihydropyridine CCB reducing clopidogrel effect, but the clinical implication is unclear. This study test the hypothesis that there is no significant effect of dihydropyridines CCB on clopidogrel response compared with control. After giving consent, patients with suboptimal blood pressure or anginal control will be randomized to receive either dihydropyridine CCB or non-CCB as placebo. These patient will be follow-up in 1 month.

Conditions

Ischemic Heart Disease

Keywords

Clopidogrel; Platelet reactivity; Amlodipine

Outcome Measures

Primary Outcomes (1)

• Platelet reactivity unit

  Platelet reactivity unit as measured by VerifyNow system

  baseline and 4 th week

Secondary Outcomes (1)

• Percentage inhibition of platelet activity

  baseline and 4th week

Study Arms (2)

non-amlodipine

ACTIVE COMPARATOR

For patient with suboptimal angina control: anti-anginal agent excluding calcium channel blocker

Drug: Amlodipine

non - amlodipine

ACTIVE COMPARATOR

For patient with suboptimal BP control: anti-hypertensive agent excluding calcium channel blocker

Drug: Amlodipine

Interventions

Amlodipine DRUG

For patient with suboptimal angina control: oral 2.5-10mg daily

Also known as: Norvasc

non-amlodipine

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• ischemic heart disease patient, and
• given loading or maintenance dose of clopidogrel and in need of it for 1 or more month
• and in need of additional drug for optimal BP control (aim blood pressure \<130/90) or angina control.

You may not qualify if:

• existing use of amlodipine
• thrombocytopenia
• end stage renal failure
• allergy to clopidogrel/ amlodipine
• pregnancy/ lactation
• strong inhibitor or inducer of cytochrome P450 3A4 enzyme within 7 days before start of the study.

Sponsors & Collaborators

• Ruttonjee Hospital: lead

Study Sites (1)

Ruttonjee Hospital

Hong Kong SAR, China

Location

Related Publications (1)

• Li AY, Ng FH, Chan FK, Tunggal P, Chan K, Lau YK. Effect of amlodipine on platelet inhibition by clopidogrel in patients with ischaemic heart disease: a randomised, controlled trial. Heart. 2013 Apr;99(7):468-73. doi: 10.1136/heartjnl-2012-302801. Epub 2012 Oct 31.

  PMID: 23118347 DERIVED

MeSH Terms

Conditions

Myocardial Ischemia

Interventions

Amlodipine

Condition Hierarchy (Ancestors)

Heart Diseases; Cardiovascular Diseases; Vascular Diseases

Intervention Hierarchy (Ancestors)

Dihydropyridines; Pyridines; Heterocyclic Compounds, 1-Ring; Heterocyclic Compounds

Study Officials

• Andrew YW Li, MB

  Ruttonjee Hospital

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: PARALLEL
• Sponsor Type: OTHER
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: September 15, 2010
• First Posted: September 16, 2010
• Study Start: July 1, 2010
• Primary Completion: April 1, 2011
• Study Completion: April 1, 2011
• Last Updated: June 6, 2012

Record last verified: 2012-06

Locations

CN (1)