Significance of Antibodies to Heparin/Platelet Factor 4 Complex in Vein Graft Patency and Potential Role of Argatroban for Prevention of Vein Graft Occlusion

October 16, 2017 updated by: Ik-Kyung Jang, MD, PhD, Massachusetts General Hospital
Heparin/Platelet Factor 4 (PF4) antibody testing will be performed in subjects who have just undergone coronary artery bypass grafting (CABG) surgery. 30 subjects with a positive antibody result and no signs or symptoms of Heparin Induced Thrombocytopenia (HIT) will be randomized to receive argatroban and warfarin. 30 subjects with a positive antibody result and no signs or symptoms of HIT will be randomized to receive no treatment. 30 subjects with a negative antibody result will also be followed in the study. All subjects will have a cardiac CT scan at about 30 days post surgery to measure the patency of their coronary artery bypass vein grafts. This study will evaluate if treating patients who have heparin PF4 antibodies post-CABG with argatroban and warfarin has any effect on the short-term patency of coronary artery bypass vein grafts.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Terminated

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This is a prospective, randomized, single center study. Patients scheduled for CABG will be screened and enrolled. Subjects positive for heparin/PF4 antibody within 24 h after CABG and without clinical suspicion of HIT will be randomized into one of two groups. An additional 30 patients with negative antibody titers will serve as a control group.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
9

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 4

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

  • United States
    • Massachusetts
      • Boston, Massachusetts, United States, 02474
        • Massachusetts General Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

14 years and older (Adult, Older Adult)

Accepts Healthy Volunteers

No

Genders Eligible for Study

All

Description

Inclusion Criteria:

  1. Patients scheduled for CABG (males or non-pregnant females)
  2. > 18 years old with at least one vein graft planned
  3. Able to provide written informed consent

Exclusion Criteria:

  1. Patients who, in the investigator's or attending surgeon's opinion, are unsuitable for anticoagulation due to their clinical status
  2. Documented history of allergy to iodinated contrast media, warfarin, or argatroban
  3. Chronic renal impairment with CrCl<60 ml/min
  4. Recent bleeding episode
  5. Congestive Heart Failure (EF< 30%)
  6. Bleeding diathesis or known thrombophilic disorder
  7. Atrial fibrillation or other condition requiring anticoagulation at the time of enrollment
  8. Documented history of heparin induced thrombocytopenia
  9. Clinical suspicion of HIT at the time of randomization, defined as 50% decrease in Platelet count from last heparin exposure or Platelet count <100,000/ml
  10. Hepatic dysfunction (defined as LFTs > 3 times the upper limit of normal)
  11. Patients with a history of bleeding complications post-CABG
  12. Hemorrhagic stroke
  13. Gastrointestinal bleeding
  14. Requirement for fresh frozen plasma
  15. Recent central nervous system or ophthalmic surgery
  16. Aneurysm
  17. History of psychosis or senility
  18. Malignant hypertension
  19. Clinically significant pericarditis or pericardial effusion
  20. Bacterial endocarditis
  21. Hematocrit < 24%
  22. Valve replacement or repair at time of CABG
  23. Subjects with signs or symptoms of possible Transient Ischemic Attack or stroke

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Other
  • Allocation: Randomized
  • Interventional Model: Factorial Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: Heparin PF4 antibody positive -Drug (argatroban and warfarin)
Post-CABG heparin PF4 antibody positive with no signs or symptoms of HIT randomized to receive argatroban and warfarin
Drug: Argatroban and warfarin
Subjects with the presence of heparin PF4 antibodies without signs or symptoms of HIT post CABG will be randomized to receive argatroban and warfarin or no drug for one month.
No Intervention: Heparin PF4 antibody positive no drug
Post-CABG heparin PF4 antibody positive with no signs or symptoms of HIT randomized to receive no medication
No Intervention: Heparin PF4 antibody negative
Post-CABG heparin PF4 antibody negative with no signs or symptoms of HIT randomized to receive no medication

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Coronary Artery Bypass Vein Graft Patency
Time Frame: Approximately 30 Days post CABG
Vein graft patency as measured by computed tomography
Approximately 30 Days post CABG

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Major Bleeding Events.
Time Frame: At 2weeks post CABG
Intracranial bleed or any clinically overt sign of hemorrhage that is associated with a fall in hemoglobin > 5 g/dL.
At 2weeks post CABG

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Massachusetts General Hospital

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
GlaxoSmithKline

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
November 1, 2010

Primary Completion (Actual)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
July 1, 2011

Study Completion (Actual)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
July 1, 2011

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
November 17, 2010

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
November 19, 2010

First Posted (Estimate)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
November 23, 2010

Study Record Updates

Last Update Posted (Actual)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
November 17, 2017

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
October 16, 2017

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
October 1, 2017

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • 2010P001386

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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