Determining the Effect of Abacavir on Platelet Activation

This study has been completed.
Information provided by (Responsible Party):
Bayside Health Identifier:
First received: June 24, 2013
Last updated: May 21, 2015
Last verified: May 2015

HIV positive patients have a two fold increased risk of developing cardiovascular disease (such as heart attacks and strokes). Cardiovascular disease appears to be due in part to both HIV and the side effects from anti-HIV medications.

Abacavir (an important component of current HIV treatment regimens) is one medication shown to be associated with an increase the risk of heart attacks in some studies. The mechanism by which abacavir does this is unknown.

We hypothesise that abacavir is leading to heart disease by interacting with platelets, which then form blood clots within the arteries supplying the heart, the subsequent blockage of the artery causing a heart attack.

This study aims to determine if abacavir increases the activity (or "stickiness") of platelets, and thus provide evidence as to how it may be promoting heart attacks.

It will consist of 23 HIV positive men who currently have well controlled HIV. Participants will take abacavir for 15 days in addition to their usual anti-HIV medications. A blood sample to assess platelet activity will be taken at baseline, following the 15 days of therapy (i.e. at the time of maximal abacavir effect) and again after a 28 day washout period (to determine if any effects are reversible).

Condition Intervention Phase
Cardiovascular Disease
Drug: Abacavir
Phase 4

Study Type: Interventional
Study Design: Endpoint Classification: Pharmacodynamics Study
Intervention Model: Single Group Assignment
Masking: Open Label
Primary Purpose: Treatment
Official Title: Determining the Effect of Abacavir on Platelet Activation in Virologically Suppressed HIV Positive Men: an Open Label Interventional Study

Resource links provided by NLM:

Further study details as provided by Bayside Health:

Primary Outcome Measures:
  • Change in Phosphorylated Vasodilator Stimulated Phosphoprotein (P-VASP) assay [ Time Frame: Baseline, day 15 and day 48 ] [ Designated as safety issue: No ]

Secondary Outcome Measures:
  • Platelet aggregation [ Time Frame: Baseline, Day 15 and day 48 ] [ Designated as safety issue: No ]
    Measurement of the degree of platelet aggregation in response to collagen related peptide and thrombin receptor-agonist peptide

  • Platelet specific collagen receptor glycoprotein VI (GPVI) [ Time Frame: Baseline, Day 15 and Day 48 ] [ Designated as safety issue: No ]
    Measurement of the expression and shedding of platelet specific collagen receptor GPVI

Enrollment: 23
Study Start Date: August 2013
Study Completion Date: October 2014
Primary Completion Date: June 2014 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Abacavir
Abacavir 600mg (as two 300mg tablets) once daily for 15 days
Drug: Abacavir
Other Name: Ziagen


Ages Eligible for Study:   18 Years and older
Genders Eligible for Study:   Male
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • > 18 years of age
  • Male
  • HIV positive
  • Stable non-abacavir containing anti-retroviral regimen
  • Undetectable HIV Viral load

Exclusion Criteria:

  • HLA-B*57*01 allele positivity
  • Previous allergy to abacavir
  • Known cardiovascular disease
  • High Baseline cardiovascular risk (Framingham risk score > 20%)
  • Current or recent antiplatelet therapy
  • Pre-existing platelet or bleeding disorder (i.e. Thrombophilia, Thrombocytopenia, Von willebrands disease, Haemophilia)
  • Significant Chronic liver disease
  • Current Methadone use
  Contacts and Locations
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Please refer to this study by its identifier: NCT01886638

Australia, Victoria
Alfred Health
Melbourne, Victoria, Australia, 3004
Sponsors and Collaborators
Bayside Health
Principal Investigator: Jennifer Hoy, MBBS FRACP Alfred health, Monash University
Principal Investigator: Janine Trevillyan, MBBS FRACP Alfred Health, Monash university
  More Information

No publications provided

Responsible Party: Bayside Health Identifier: NCT01886638     History of Changes
Other Study ID Numbers: 248-13, ACTRN12613000570785
Study First Received: June 24, 2013
Last Updated: May 21, 2015
Health Authority: Australia: Department of Health and Ageing Therapeutic Goods Administration
Australia: Human Research Ethics Committee

Keywords provided by Bayside Health:
Cardiovascular disease
Acute myocardial infarction

Additional relevant MeSH terms:
Cardiovascular Diseases
Anti-HIV Agents
Anti-Infective Agents
Anti-Retroviral Agents
Antiviral Agents
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Nucleic Acid Synthesis Inhibitors
Pharmacologic Actions
Reverse Transcriptase Inhibitors
Therapeutic Uses processed this record on November 24, 2015