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Tenofovir Abacavir Platelet Activation Study (TAPAS)

This study is ongoing, but not recruiting participants.
Sponsor:
ClinicalTrials.gov Identifier:
NCT02093585
First Posted: March 21, 2014
Last Update Posted: May 12, 2017
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details.
Information provided by (Responsible Party):
Jan Gerstoft, Rigshospitalet, Denmark
  Purpose
Some but not all observational studies have found that current exposure to abacavir is associated with increased risk of cardiovascular events such as myocardial infarction, stroke and cardiovascular death. This study aim to investigate possible adverse effect of abacavir on platelet reactivity, coagulation and endothelial activation in HIV-1 infected patients. The study is an open-labeled cross-over trial, where patients receiving antiretroviral therapy containing abacavir switch treatment to a regimen containing tenofovir and vice versa for a period of 90 days.

Condition Intervention Phase
HIV Drug: abacavir (600 mg QD) Drug: tenofovir (245 mg QD) Phase 4

Study Type: Interventional
Study Design: Allocation: Non-Randomized
Intervention Model: Crossover Assignment
Masking: None (Open Label)
Primary Purpose: Other
Official Title: Changes in Coagulation and Platelet Reactivity in HIV-1 Infected Patients Switching Between Abacavir and Tenofovir Containing Antiretroviral Regimens

Resource links provided by NLM:


Further study details as provided by Jan Gerstoft, Rigshospitalet, Denmark:

Primary Outcome Measures:
  • Differences in platelet aggregation (Multiplate) before and after switching between abacavir and tenofovir. [ Time Frame: before and after 90 days intervention ]
  • Differences in clot formation kinetics (thromboelastography) before and after switching between abacavir and tenofovir. [ Time Frame: before and after 90 days intervention ]

Secondary Outcome Measures:
  • Concentration of plasma lipids [ Time Frame: Before and after 90 days intervention ]
  • activated partial thromboplastin time (APTT) [ Time Frame: 90 days ]
  • international normalized ratio (INR)/Factor II, VII, X [ Time Frame: Before and after 90 days intervention ]
  • Platelet count [ Time Frame: Before and after 90 days intervention ]
  • Fibrinogen [ Time Frame: Before and after 90 days intervention ]
  • D-dimer [ Time Frame: Before and after 90 days intervention ]
  • Antithrombine [ Time Frame: Before and after 90 days intervention ]
  • Interleukin 6 (IL-6) [ Time Frame: Before and after 90 days intervention ]
  • High sensitivity C reactive protein (HS-CRP) [ Time Frame: Before and after 90 days intervention ]
  • Soluble P-Selectin [ Time Frame: Before and after 90 days intervention ]
  • soluble CD40 ligand (sCD40L) [ Time Frame: Before and after 90 days intervention ]
  • Syndecan-1 [ Time Frame: Before and after 90 days intervention ]
  • Soluble E-selectin [ Time Frame: Before and after 90 days intervention ]
  • Tissue plasminogen activator [ Time Frame: Before and after 90 days intervention ]

Estimated Enrollment: 100
Study Start Date: January 2014
Estimated Study Completion Date: June 2017
Primary Completion Date: April 2016 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Experimental: Tenofovir to abacavir
Patients switching from tenofovir (245 mg QD) to abacavir (600 mg QD)
Drug: abacavir (600 mg QD)
Experimental: Abacavir to tenofovir
Patients switching from abacavir (600 mg QD) to tenofovir (245 mg QD)
Drug: tenofovir (245 mg QD)

  Eligibility

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Ages Eligible for Study:   35 Years to 70 Years   (Adult, Senior)
Sexes Eligible for Study:   Male
Accepts Healthy Volunteers:   No
Criteria

Inclusion Criteria:

  • HIV-1 infected
  • Can understand and sign written informed consent
  • Received one of the above mentioned antiretroviral regimens continuously ≥ 6 months
  • HIV RNA < 400 copies/mL for ≥ 6 months

Exclusion Criteria:

  • Receiving anticoagulant therapy, adenosine diphosphate (ADP) receptor inhibitors, aspirin or nonsteroidal antiinflammatory drugs (NSAIDs)
  • Previous ischemic heart disease, peripheral atherosclerotic disease or stroke
  • Coagulation disorder (e.g. hemophilia, factor V Leiden mutation)
  • Platelet count < 150 x 109/L during the past 6 months from inclusion
  • Estimated glomerular filtration rate (eGFR) <70 during the past 6 months from inclusion
  • Humane leukocyte antigen (HLA)-B*57:01 positive genotype
  • Hepatitis B or C positive during the past year from inclusion
  • Hypersensitivity to the active substances or to any of the excipients
  Contacts and Locations
Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02093585


Locations
Denmark
Rigshospitalet, Klinik for Infektionsmedicin og Reumatologi, 8622
Copenhagen Ø, Copenhagen, Denmark, 2100
Sponsors and Collaborators
Jan Gerstoft
Investigators
Principal Investigator: Jan Gerstoft, MD, DMSc Rigshospitalet, Denmark
  More Information

Responsible Party: Jan Gerstoft, MD, DMSc, Professor, Rigshospitalet, Denmark
ClinicalTrials.gov Identifier: NCT02093585     History of Changes
Other Study ID Numbers: 2013-001685-42
First Submitted: March 18, 2014
First Posted: March 21, 2014
Last Update Posted: May 12, 2017
Last Verified: May 2017

Keywords provided by Jan Gerstoft, Rigshospitalet, Denmark:
HIV-1
Abacavir
Platelet activation
Thromboelastography
Coagulation

Additional relevant MeSH terms:
Tenofovir
Abacavir
Dideoxynucleosides
Antiviral Agents
Anti-Infective Agents
Reverse Transcriptase Inhibitors
Nucleic Acid Synthesis Inhibitors
Enzyme Inhibitors
Molecular Mechanisms of Pharmacological Action
Anti-Retroviral Agents
Anti-HIV Agents
Antimetabolites