Atrial FibrillationNCT03199521
Assessment of The Effect of Apixaban in AF
An observational study of Atrial Fibrillation and Embolism Thrombosis, run by East and North Hertfordshire NHS Trust at 1 site in United Kingdom.
Trial summary
This study will assess the effect of apixaban on thrombotic status in patients with atrial fibrillation.In addition it will compare apixaban to aspirin and warfarin on their effect on endogenous fibrinolysis. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Atrial Fibrillation, Embolism Thrombosis
- What is being tested?
- Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)
- How many people
- 240 participants
- Where
- 1 siteUnited Kingdom
- Study dates
- 1 Jun 2017to 2 Jan 2019
- Phase
- Observational
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Patients with non-valvular atrial fibrillation. Participants will be recruited via inpatient and outpatient clinical areas.
Who may be able to join
- Age >18 years
- Diagnosis of NVAF (nonvalvular atrial fibrillation)
- Requiring anticoagulation or antiplatelet therapy for thromboprophylaxis of stroke and systemic embolism
- No contra-indications to apixaban (except for those patients taking part in baseline cross-sectional study where this inclusion criterion does not apply)
- Patient does not meet any of the exclusion criteria below
Who cannot join
- Patient unwilling or unable to give informed consent
- Patient already taking antiplatelet or anticoagulant therapy (except for those patients taking part in baseline cross-sectional study, where this exclusion criterion does not apply)
- Patient who, in the opinion of the investigator, has significant hepatic or renal impairment likely to cause a bleeding diathesis
- Patient needing systemic high dose steroids or immunosuppression that may impact on platelet function
- Patient with ongoing active alcohol or substance abuse or demonstrates signs or clinical features of active substance abuse
- Patient with any major bleeding diathesis or blood dyscrasia at baseline (platelets<70 x 109/l, Hb<80 g/l, INR >1.4 (international normalized ratio), APTT (activated partial thromboplastin time ) > x 2UNL (upper normal limit) , leucocyte count< 3.5x 109/l, neutrophil count<1x 109/l).
- Patient currently involved in another investigational trial of a medicine or medical device
Trial locations and contacts
1 site in 1 country.
United Kingdom1 site
Hertfordshire Cardiology Centre, East and North Hertfordshire NHS Trust
Stevenage, SG14AB
About this study
Official title: Assessing The Effect of Apixaban on Endogenous Fibrinolysis in Patients With Non-Valvular Atrial Fibrillation
This study will assess the effect of apixaban on thrombotic status in patients with atrial fibrillation.In addition it will compare apixaban to aspirin and warfarin on their effect on endogenous fibrinolysis.
Read the detailed description
Patients with an irregular heart rhythm called atrial fibrillation (AF) have an increased risk of forming blood clots inside the heart, that can then fragment and break off, travelling through the circulation to the brain, where it can cause blockage of the small blood vessels resulting in a stroke. Most patients with AF are prescribed blood thinning medications in an attempt to prevent such clot formation. The body has the ability through enzymes circulating in blood, to dissolve a clot once formed, such that even if a clot is formed, it is rapidly dissolved and no lasting damage is sustained. This is known as endogenous fibrinolysis. If this defence system is faulty or suboptimal, there is an increased risk of clot formation, resulting in stroke or heart attack. Currently, there are no available tablets to favourably modify this defence system of endogenous fibrinolysis. The investigators will assess how this defence system functions in patients with AF who are on different blood thinners. Then the investigators will also assess a group of patients before and during treatment with a relatively new blood thinner called apixaban, to assess the effect of this on the stickiness of blood and the ability of the blood to dissolve clots (endogenous fibrinolysis). All the blood thinners will be prescribed for clinical indications, not as part of the research. The research aspect of the study is that we will perform a blood test to assess endogenous fibrinolysis.
Understanding the effect of apixaban on endogenous fibrinolysis raises the possibility that apixaban, rather than other blood thinners, may be of particular use in patients with impaired fibrinolysis who are at particularly high risk of clots due to inefficient endogenous fibrinolysis.
- Conditions
- Atrial Fibrillation, Embolism Thrombosis
- Being tested
- Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)
- Keywords
- apixaban, endogenous fibrinolysis, warfarin, aspirin, thrombotic status
- Medical subject headings
- Atrial Fibrillation, Embolism and Thrombosis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)Other
Global Thrombosis Test (GTT): assesses formation of the blood clot and how easily can this be broken down once formed) Thromboelastography (TEG) :assesses the properties of a blood clot and how easily can be broken down Thrombin generation assays: assesses the formation of a blood clot and the potential of thrombolysis via the introduction of different buffer solutions
| Study group | Role | What they receive |
|---|---|---|
| Atrial Fibrillation newly diagnosed, starting apixaban | Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays before and after stabilisation(4 weeks) of their anticoagulation. This will allow to compare the effect of apixaban on endogenous fibrinolysis before and after treatment. Receives: Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT) | |
| Atrial fibrillation on stable warfarin treatment | Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays on stable anticoagulation treatment. This will allow to compare the effect of apixaban against warfarin on endogenous fibrinolysis on stable treatment. Receives: Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT) | |
| Atrial Fibrillation on stable aspirin treatment | Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays on stable anticoagulation treatment. This will allow to compare the effect of apixaban against aspirin on endogenous fibrinolysis on stable treatment. Receives: Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT) |
What is being measured
The primary outcome is the main question the study is designed to answer.
Assessing the effect of apixaban on endogenous fibrinolysis in patients wth atrial fibrillation
Measuring endogenous fibrinolysis before and after apixaban
Measured: Change of endogenous fibrinolysis from baseline at 4 weeks
Secondary outcomes (1)
Comparing the effect of apixaban to warfarin and aspirin on endogenous fibrinolysis in patients with atrial fibrillation
Compare the effect on endogenous fibrinolysis as measured by occlusion time and lysis time (seconds) of stable apixaban, warfarin and aspirin treatment in patients with atrial fibrillation with the GTT,TEG,thrombin generation assays
Measured: 12 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted27 Jun 2017
- Study start1 Jun 2017
- Primary completion2 Jan 2019
- Study completion2 Jan 2019
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Atrial FibrillationStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 240 participants (actual)
Sponsor and investigators
- Lead sponsor
- East and North Hertfordshire NHS Trust
- Sponsor type
- Other government
- Collaborators
- University of Hertfordshire
- Responsible party
- Principal investigator, Prof Diana Gorog, East and North Hertfordshire NHS Trust
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT03199521
- Sponsor's protocol ID
- No 1.1 Apr 2017
- Other IDs
- CV185-622, RD2017-03
- Status last verified
- Feb 2019
- First submitted
- 13 Jun 2017
- Last updated
- 7 Feb 2019
- Results posted
- No
- Data monitoring committee
- Yes
- Individual data sharing
- Yes
Study at a glance
From the registry record, last updated by the sponsor on 7 Feb 2019. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Assessing The Effect of Apixaban on Endogenous Fibrinolysis in Patients With Non-Valvular Atrial Fibrillation
- ClinicalTrials.gov ID
- NCT03199521
- Acronym / sponsor ID
- No 1.1 Apr 2017
- Conditions
- Atrial Fibrillation, Embolism Thrombosis
- Keywords
- apixaban, endogenous fibrinolysis, warfarin, aspirin, thrombotic status
- Study type
- Observational
- Recruitment status
- Completed
- Enrolment
- 240 participants (actual)
- Lead sponsor
- East and North Hertfordshire NHS TrustOther government
- Collaborators
- University of Hertfordshire
- Study start
- 1 Jun 2017 (actual)
- Primary completion
- 2 Jan 2019 (actual)
- Study completion
- 2 Jan 2019 (actual)
- First posted
- 27 Jun 2017 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study will assess the effect of apixaban on thrombotic status in patients with atrial fibrillation.In addition it will compare apixaban to aspirin and warfarin on their effect on endogenous fibrinolysis.
Detailed description
Patients with an irregular heart rhythm called atrial fibrillation (AF) have an increased risk of forming blood clots inside the heart, that can then fragment and break off, travelling through the circulation to the brain, where it can cause blockage of the small blood vessels resulting in a stroke. Most patients with AF are prescribed blood thinning medications in an attempt to prevent such clot formation. The body has the ability through enzymes circulating in blood, to dissolve a clot once formed, such that even if a clot is formed, it is rapidly dissolved and no lasting damage is sustained. This is known as endogenous fibrinolysis. If this defence system is faulty or suboptimal, there is an increased risk of clot formation, resulting in stroke or heart attack. Currently, there are no available tablets to favourably modify this defence system of endogenous fibrinolysis. The investigators will assess how this defence system functions in patients with AF who are on different blood thinners. Then the investigators will also assess a group of patients before and during treatment with a relatively new blood thinner called apixaban, to assess the effect of this on the stickiness of blood and the ability of the blood to dissolve clots (endogenous fibrinolysis). All the blood thinners will be prescribed for clinical indications, not as part of the research. The research aspect of the study is that we will perform a blood test to assess endogenous fibrinolysis.
Understanding the effect of apixaban on endogenous fibrinolysis raises the possibility that apixaban, rather than other blood thinners, may be of particular use in patients with impaired fibrinolysis who are at particularly high risk of clots due to inefficient endogenous fibrinolysis.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| Atrial Fibrillation newly diagnosed, starting apixaban | – | Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays before and after stabilisation(4 weeks) of their anticoagulation. This will allow to compare the effect of apixaban on endogenous fibrinolysis before and after treatment. |
| Atrial fibrillation on stable warfarin treatment | – | Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays on stable anticoagulation treatment. This will allow to compare the effect of apixaban against warfarin on endogenous fibrinolysis on stable treatment. |
| Atrial Fibrillation on stable aspirin treatment | – | Other: Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)Patients will undergo the global thrombosis test (GTT), thromboelastography (TEG) and thrombin generation assays on stable anticoagulation treatment. This will allow to compare the effect of apixaban against aspirin on endogenous fibrinolysis on stable treatment. |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Patients with non-valvular atrial fibrillation. Participants will be recruited via inpatient and outpatient clinical areas.
Key inclusion criteria (5 listed)
- Age >18 years
- Diagnosis of NVAF (nonvalvular atrial fibrillation)
- Requiring anticoagulation or antiplatelet therapy for thromboprophylaxis of stroke and systemic embolism
- No contra-indications to apixaban (except for those patients taking part in baseline cross-sectional study where this inclusion criterion does not apply)
- Patient does not meet any of the exclusion criteria below
Key exclusion criteria (7 listed)
- Patient unwilling or unable to give informed consent
- Patient already taking antiplatelet or anticoagulant therapy (except for those patients taking part in baseline cross-sectional study, where this exclusion criterion does not apply)
- Patient who, in the opinion of the investigator, has significant hepatic or renal impairment likely to cause a bleeding diathesis
- Patient needing systemic high dose steroids or immunosuppression that may impact on platelet function
- Patient with ongoing active alcohol or substance abuse or demonstrates signs or clinical features of active substance abuse
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Thrombin generation assays, Thromboelastography (TEG), and Global Thrombosis Test (GTT)Global Thrombosis Test (GTT): assesses formation of the blood clot and how easily can this be broken down once formed) Thromboelastography (TEG) :assesses the properties of a blood clot and how easily can be broken down Thrombin generation assays: assesses the formation of a blood clot and the potential of thrombolysis via the introduction of different buffer solutions | Other | Atrial Fibrillation newly diagnosed, starting apixaban, Atrial Fibrillation on stable aspirin treatment, Atrial fibrillation on stable warfarin treatment |
Primary outcome
Assessing the effect of apixaban on endogenous fibrinolysis in patients wth atrial fibrillation
Time frame: Change of endogenous fibrinolysis from baseline at 4 weeks
Measuring endogenous fibrinolysis before and after apixaban
1 secondary outcome
Comparing the effect of apixaban to warfarin and aspirin on endogenous fibrinolysis in patients with atrial fibrillation
Time frame: 12 months
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 7 Feb 2019.
- Individual participant dataSharing planned: Yes
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
The record lists no contact. Use the official record to reach the sponsor.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of Atrial Fibrillation and Embolism Thrombosis, run by East and North Hertfordshire NHS Trust at 1 site in United Kingdom.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 5 inclusion and 7 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 7 Feb 2019. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United Kingdom. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Assessing the effect of apixaban on endogenous fibrinolysis in patients wth atrial fibrillation (time frame: Change of endogenous fibrinolysis from baseline at 4 weeks). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 7 Feb 2019.