Please select the eligibility criteria that correspond to the clinical trial below.
Title: Dabigatran Following Transient Ischemic Attack and Minor Stroke
Brief Summary: Rationale: To date, anticoagulant therapy in acute stroke has also been limited by excess hemorrhagic events. The oral anticoagulant dabigatran is a novel agent, which has been shown to be associated with much lower intracranial hemorrhage rates. It has been suggested that this agent may provide the superior benefits of anticoagulation in acute stroke, without the concomitant increase in hemorrhage risk associated with heparin/LMWH or warfarin.

Study Design: DATAS II is a randomized, open label blinded endpoint trial. Participants (n=300) with TIA or ischemic stroke (NIHSS score \<9) will be enrolled within 48 hours of symptom onset from approximately four (4) health care centres across Canada. All participants will have an MRI with DWI lesion volume \< 25 ml. Participants will be randomized 1:1 to treatment with dabigatran for 30 days or ASA 81 mg daily (current standard of care). All stroke patients will initially be screened with a non-contrast CT scan of the brain. The first MRI will be performed within 48 hours of symptom onset. Imaging studies will be repeated at day 30. All patients will be assessed clinically at Day 30 and Day 90.

Study Aims:

1. Establish the safety of early anticoagulation with the novel oral anticoagulant dabigatran in acute cerebrovascular syndrome patients.
2. Identify the rate of both symptomatic and asymptomatic hemorrhagic transformation (HT) associated with these treatments.
3. Identify predictors of HT associated with acute dabigatran treatment.

Hypothesis: The Investigators hypothesize that symptomatic HT rates in dabigatran and ASA treated patients will not be significantly different.

Study outcomes: The primary outcome is the rate of symptomatic hemorrhagic transformation (HT), defined as a parenchymal hematoma, which is \>30% of the infarcted area on DWI, with substantial space- occupying effect, associated with clinical worsening (≥4 point increase in National Institutes of Health Stroke Scale (NIHSS) score) within 5 weeks of treatment initiation. The major secondary outcome the rate of asymtomatic HT see on day 30 MRI sequence.


Options:
A: Inclusion Criteria:

1. Male or female patients
2. Must be \>18 years of age
3. Must have TIA or ischemic stroke (NIHSS score \<9 - see section 2.7 for further clarification)
4. Symptom onset is \< 72 hours prior to enrollment or Study therapy must initiated within 48 hours of symptom onset (in case where onset time cannot be established, it will be considered to be the time when the patient was lst know to be well
5. Informed consent must be obtained from either the patient or substitute decision maker (according to local REB policy) prior to any study related procedures being performed
6. All patients will have a MRI including DWI prior to randomization
7. DWI lesion volume must be \<25ml
8. Patients without DWI lesions, but a clinical history considered consistent with TIA, determined by the attending physician, can be included

Exclusion Criteria:

1. Patients with stroke mimics - such as seizures, migraine etc
2. Patients with contraindications to MRI including metallic implants
3. Patients with any past sensitivity to gadolinium contrast media will be eligible, but will not undergo PWI or contrast enhanced MRA (both optional sequences)
4. Patients with renal failure defined as Glomerular Filtration Rate (GFR) \< 30 ml/min
5. Patients deemed, as attending stroke physician, to have any ongoing bleeding risks or unsuitable for dabigatran therapy
6. Patients with MRI demonstrated additional pathology including arteriovenous malformations, intracranial aneurysms, tumors or abscess, which potentially increase the rise of bleed. Individuals with small incidental leasions, at low risk of bleed such as meningiomas may be included at the discretion of the investigator.
7. Patients with an acute DWI lesion volume of \>25 ml (DWI volume to be estimated using the ABC/2 technique 110)\*\*
8. Age \<18 years
9. Pregnant or breast feeding women.
10. Severe dysphagia necessitating naso-gastric (NG) feeding (dabigatran can not be delivered via NG tube)
11. Planned thrombolysis or endovascular intervention for the index event
12. Thrombolysis for ischemic stroke within the preceding 7 days
13. Planned carotid endarterectomy/carotid artery stent within 30 days Note: Carotid Investigations will be completed prior to enrolment. Patients with symptomatic stenoses and a planned carotid procedure will be excluded.
14. Any history of spontaneous intracranial bleeding
15. Clear indication for anticoagulation, including atrial fibrillation, mechanical cardiac valves, deep venous thrombosis, pulmonary embolism or known hypercoagulable state
16. Co-morbid illness with expected life expectancy of \<90 days
B: Inclusion Criteria:

1. Signed Written Informed Consent
2. Males and Females over 18 years of age.
3. History of Nonvalvular Atrial Fibrillation (NVAF) by documentation in the medical history or newly diagnosed nonvalvular Atrial Fibrillation at time of study randomization by ECG, device or telemetry .
4. Diagnosis of TIA or small or medium ischemic stroke 0 to 48 hours from signs or symptoms.
5. Women of child-bearing potential must use a reliable method of contraception and must provide a negative pregnancy test at entry into the study and within 24 hours of study treatment initiation.
6. WOCBP must agree to follow instructions for method(s) of contraception for the duration of treatment with study drug Apixaban plus 5 half-lives (approximately 3 days) plus 30 days (duration of ovulatory cycle) for a total of 33 days post-treatment completion.
7. Males who are sexually active with WOCBP must agree to follow instructions for method(s) of contraception for the duration of treatment with Apixaban plus 5 half-lives (approximately 3 days) plus 90 days (duration of sperm turnover) for a total of 93 days post-treatment completion.
8. Azoospermic males and WOCBP who are continuously not heterosexually active are exempt from contraceptive requirements. However they must still undergo pregnancy testing as described in this section.

Investigators shall counsel WOCBP and male subjects who are sexually active with WOCBP on the importance of pregnancy prevention and the implications of an unexpected pregnancy Investigators shall advise WOCBP and male subjects who are sexually active with WOCBP on the use of highly effective methods of contraception. Highly effective methods of contraception have a failure rate of \< 1% when used consistently and correctly.

At a minimum, subjects must agree to the use of one method of highly effective contraception as listed below:

HIGHLY EFFECTIVE METHODS OF CONTRACEPTION

* Male condoms with spermicide
* Hormonal methods of contraception including combined oral contraceptive pills, vaginal ring, injectables, implants and intrauterine devices (IUDs) such as Mirena by WOCBP subject or male subject's WOCBP partner. Female partners of male subjects participating in the study may use hormone based contraceptives as one of the acceptable methods of contraception since they will not be receiving study drug
* IUDs, such as ParaGard™
* Tubal ligation
* Vasectomy.
* Complete Abstinence

Exclusion Criteria:

1. Hemorrhagic stroke
2. Large ischemic stroke
3. History of major bleeding within the last 6 months from time of subject enrollment (e.g. GI bleed).
4. History of intracranial bleed

   a. Traumatic intracranial bleed within one year of randomization. (Traumatic ICH greater than one year of randomization is not an exclusion).
5. Current or history of bleeding disorders (e.g. blood dycrasias)
6. Blood Pressure of 180/100 mmHg on hypertensive therapy day of randomization per PI discretion 20.
7. Current illicit drug use and/or chronic alcohol use per PI discretion.
8. Severe liver disease (AST/ALT 2x upper limit).
9. Patients with kidney disease meeting criteria to take 2.5 mg twice daily who are taking strong dual inhibitors of CYP3A4 and P-glycoprotein (e.g. ketoconazole, itraconazole, ritonavir, clarithromycin) .
10. Any other suspected etiology for stroke (e.g. ipsilateral carotid disease).
11. Greater than 3 Cerebral Micro-bleeds (CMB) on gradient recovery echo (GRE) or evidence of intracranial hemorrhage on CT at time of randomization. (SWI sequencing may be used if GRE sequencing is not obtainable)
12. Therapeutically anti-coagulated at time of admission (INR at admission greater than 2.0 on warfarin or took two consecutive doses of NOAC).
13. Absolute indication for use of warfarin only.( e.g. Mechanical Valve)
14. Absolute indication for anticoagulation prior to randomization window. (e.g. DVT)
15. Hemoglobin less than 9 gm/dl and/or platelet count less than 100 K/uL.
16. Requires dual antiplatelet therapy.
17. Daily use of NSAIDS
18. Pregnancy or lactation.
19. Any use of an investigational product within the past 30 days.
20. Prisoners or subjects who are involuntarily incarcerated.
21. Subjects who are compulsorily detained for treatment of either a psychiatric or physical (eg, infectious disease) illness.
22. Concurrent participation in another clinical study where use of an investigational product is used
C: Inclusion Criteria:

1. Provision of signed informed consent prior to any study-specific procedure
2. ≥40 years of age
3. Acute onset of cerebral ischaemia due to

   1. AIS with NIHSS ≤5. AIS is defined as acute onset of neurological deficit attributed to focal brain ischaemia, and either of the following:

      * Persistent signs or symptoms of the ischaemic event at the time o randomisation, OR
      * Acute ischaemic brain lesion documented before randomisation by computed tomography (CT) scan or magnetic resonance imaging (MRI) (diffusion-weighted imaging) and that could account for the clinical presentation
   2. High-risk TIA, defined as neurological deficit of acute onset attributed to focal ischaemia of the brain by history or examination with complete resolution of the deficit, and at least one of the following:

      * ABCD2 score ≥6 and TIA symptoms not limited to isolated numbness, isolated visual changes, or isolated dizziness/vertigo
      * Symptomatic intracranial arterial occlusive disease that could account for the clinical presentation, documented by transcranial Doppler or vascular imaging and defined as at least 50% narrowing in the diameter of the vessel lumen
      * Internal carotid arterial occlusive disease that could account for the clinical presentation, documented by Doppler, ultrasound, or vascular imaging and defined as at least 50% narrowing in diameter of the vessel lumen
4. Randomisation occurring within 24 hours after onset of symptoms; for wake-up strokes (when the time of symptom onset is not known), within 24 hours from the time point at which the patient was reported to be in their normal condition
5. CT or MRI performed after symptom onset ruling out intracranial haemorrhage or other pathology, such as vascular malformation, tumour, or abscess that according

to the Investigator could explain symptoms or contraindicate study treatment

Exclusion Criteria:

1. Need for or an anticipated need for any of the following:

   1. Dual antiplatelet therapy with ASA and P2Y12 inhibitors (including patients with carotid artery stenting and percutaneous coronary intervention)
   2. Antiplatelets other than ASA (eg, GPIIb/IIIa inhibitors, clopidogrel, ticlopidine, prasugrel, dipyridamole, ozagrel, cilostazol, ticagrelor) and other antithrombotic agents with antiplatelet effects, including traditional/herbal medicine agents
   3. Anticoagulants (eg, warfarin, oral thrombin and factor Xa inhibitors, bivalirudin, hirudin, argatroban, fondaparinux, or unfractionated heparin and long-term treatment with low-molecular weight heparins). Short-term treatment (≤7 days) with low-dose low-molecular weight heparin may be used in immobilised patients at the discretion of the Investigator
2. Any history of atrial fibrillation/flutter, ventricular aneurysm, or suspicion of other cardioembolic pathology for TIA or stroke
3. Patients who should receive or have received any intravenous or intra-arterial thrombolysis or mechanical thrombectomy within 24 hours prior to randomisation
4. Planned carotid endarterectomy that requires halting investigational product within 3 days of randomisation or is expected to require unblinding of investigational product (planned carotid endarterectomy is in itself not an exclusion criterion)
5. History of previous intracranial haemorrhage at any time (asymptomatic microbleeds do not qualify), gastrointestinal haemorrhage within the past 6 months, or major surgery within 30 days
6. Patients considered to be at risk of bradycardic events (eg, known sick sinus syndrome or second- or third-degree atrioventricular block) unless already treated with a permanent pacemaker
7. Inability of the patient to understand and/or comply with study procedures and/or follow-up, in the opinion of the Investigator
8. Known hypersensitivity to ticagrelor or ASA
9. Need for or an anticipated need for oral or intravenous therapy with any of the following:

   1. Strong cytochrome P450 3A (CYP3A4) inhibitors (eg, ketoconazole, clarithromycin \[but not erythromycin or azithromycin\], nefazadone, ritonavir, atazanavir) that cannot be stopped for the course of the study
   2. Long-term (\>7 days) non-steroidal anti-inflammatory drugs
10. Known bleeding diathesis or coagulation disorder (eg, thrombotic thrombocytopenic purpura)
11. Known severe liver disease (eg, ascites or signs of coagulopathy)
12. Renal failure requiring dialysis
13. Pregnancy or breastfeeding. Women of child-bearing potential who are not willing to use a medically accepted method of contraception that is considered reliable in the judgment of the Investigator
14. Involvement in the planning and/or conduct of the study (applies to both AstraZeneca staff and/or staff at the study site)
15. Previous enrolment or randomisation in the present study
16. Participation in another clinical study with an investigational product at any time during the 30 days prior to randomisation (regardless of when treatment with the investigational product was discontinued)
D: Inclusion Criteria:

* ischemic stroke
* female or male gender
* mRS (modified Rankin Scale) 0-1 (min one month before the event)
* NIHSS ≥ 6 and ≤ 25
* Age: 18-80 years
* initiation of therapy in the interval from 4.5 to 24 hours from onset of symptoms of ischemic stroke
* focal neurological deficit of at least 30 min, which was significantly obviously does not disappear before treatment
* patient will participate voluntarily and signed informed consent. Informed consent will be obtained from each patient, guardian or close relative
* patients who are unable to sign, but who are able to understand what means to participate in the study, may give informed consent through eyewitness
* willingness and ability to comply with the protocol

Exclusion Criteria:

* intracranial hemorrhage confirmed by CT scan
* CT image heavy and extensive focal cerebral ischemia
* lacunar syndrome
* epileptic seizure at the beginning of ischemic stroke
* previous or planned treatment with intravenous, intra-arterial thrombolysis, mechanical recanalization or ultrasound assisted thrombolysis
* stroke, myocardial infarction, head trauma in the last 3 months
* tromboctov count below 100 000/mm ³
* therapeutically uncontrolled blood pressure: systolic blood pressure\> 185 mmHg or diastolic blood pressure\> 110 mmHg
* therapeutically uncontrolled blood glucose ˂ 2.77 or\> 22.15 mmol / l
* Known bleeding diathesis, other coagulopathies, severe hepatopathy, severe nephropathy
* patients receiving oral anticoagulants
* current or previous life-threatening bleeding
* major surgery less than 2 weeks ago
* known malignancy
* active TB
* pregnancy
* allergy to Heparin or Fraxiparine
* known alcohol abuse and / or drugs
* active participation in another clinical study

Answer: A