Please select the eligibility criteria that correspond to the clinical trial below.
Title: Reduced-dosed Rivaroxaban and Standard-dosed Rivaroxaban Versus ASA in the Long-term Prevention of Recurrent Symptomatic Venous Thromboembolism in Patients With Symptomatic Deep-vein Thrombosis and/or Pulmonary Embolism
Brief Summary: This is a multicenter, randomized, double-blind, event-driven, superiority study for efficacy.

Patients with confirmed symptomatic DVT (Deep Vein Thrombosis) or PE (Pulmonary embolism) who completed 6 or 12 months of treatment of anticoagulation are eligible for this trial


Options:
A: Inclusion Criteria:

* Confirmed or probable SARS-CoV-2 infection;
* Presence of acute kidney injury with indication and agreement between ICU and nephrology teams for the introduction of renal continuous venous venous hemodialysis.

Exclusion Criteria:

* Hypersensitivity to any of the substances used in the study (Citric acid dextrosol 2.2% and unfractionated heparin);
* Previous diagnosis of coagulopathy or thrombophilia;
* Contraindication to the use of unfractionated heparin by the assistant team;
* Risk of citrate poisoning - (Lactate\> 30mg / dL, RNI\> 2.5, Total bilirubin\> 15mg / dL);
* Pregnancy
B: Inclusion Criteria:

* Patients with confirmed symptomatic PE and/or DVT who have been treated for 6 to 12 months and did not interrupt anticoagulation for longer than 1 week

Exclusion Criteria:

* Legal lower age limitations (country specific) Indication for therapeutic-dosed anticoagulants Indication for antiplatelet therapy or a conventional non-steroid anti-inflammatory drug (NSAID) Hepatic disease which is associated with coagulopathy leading to a clinically relevant bleeding risk Calculated creatinine clearance \< 30 mL/min
C: Inclusion Criteria:

1. Adults ≥ 18 years old;
2. Evaluated in the emergency unit with probable or confirmed infection by COVID-19;
3. Time between symptoms and inclusion ≤ 07 days \*;
4. Present mild or moderate signs and symptoms, with no clear indication for hospitalization;
5. Present at least 2 risk factors for complication:

   * 65 years
   * Hypertension
   * Diabetes mellitus
   * Asthma
   * Chronic Obstructive Pulmonary Disease (COPD) or other chronic lung diseases
   * Smoking
   * Immunosuppression
   * Obesity (BMI\> 30)
   * History of non-active cancer
   * Bed restriction or reduced mobility (≥50% of the wake time without walking)
   * Previous history of VTE
   * Use of oral hormonal contraceptives

Exclusion Criteria:

1. Patients \<18 years old;
2. Hospitalization indication upon first medical care;
3. Positive test for influenza in the first visit;
4. Any known liver disease associated with coagulopathy; INR (International Normalized Ratio) \> 1.5;
5. Pregnant, lactating or with the possibility of becoming pregnant and without using an adequate contraceptive method;
6. High risk of bleeding; History of bronchiectasis or pulmonary cavitation, Significant bleeding in the last 3 months, Active gastroduodenal ulcer, history of recent bleeding (within 3 months) or a high risk of bleeding;
7. Stroke within 1 month or any history of hemorrhagic or lacunar stroke or any intracranial bleeding or any intracranial neoplasia, brain metastasis, arteriovenous malformation or brain aneurysm;
8. Severe heart failure with left ventricular ejection fraction \<30% (echocardiogram or other validated method previously documented) or symptoms of heart failure class III or IV of the New York Heart Association (NYHA);
9. Estimated glomerular filtration rate (eGFR) \<30 mL / min;
10. Clinical indication for dual antiplatelet therapy or anticoagulation therapy (VTE, atrial fibrillation / flutter, mechanical valve prosthesis);
11. Marked thrombocytopenia (platelets \<50,000 / mm3);
12. Non-cardiovascular disease that is associated with a poor prognosis, for example, active cancer (excluding non-melanoma skin cancer) defined as cancer without remission or requiring active chemotherapy or adjuvant therapies such as immunotherapy or radiation therapy or that increases the risk of an adverse reaction to the evaluated interventions;
13. History of hypersensitivity or known contraindication to rivaroxaban;
14. Systemic treatment with strong inhibitors of Cytochrome P450 3A4 (CYP3A4) and glycoprotein p (Pgp) (for example, systemic azole antimycotics, such as ketoconazole and human immunodeficiency virus \[HIV\] protein inhibitors, such as ritonavir) or strong inducers of CYP 3A4, that is, rifampicin, rifabutin, phenobarbital, phenytoin and carbamazepine;
15. Current treatment being tested;
16. Concomitant participation in another study with experimental drugs in the context of COVID;
17. Use of chloroquine or hydroxychloroquine associated with azithromycin;
18. Active cancer;
19. Other contraindications to rivaroxaban;
D: Inclusion Criteria:

* Symptomatic proximal DVT involving the iliac and/or common femoral vein, confirmed by Duplex Sonography, Angio-CT, Angio-MRI or Phlebography
* Written informed consent

Exclusion Criteria

* Age less than 18 years or greater than 75 years
* Symptom duration \> 14 days for the DVT episode in the index leg (i.e., non-acute DVT).
* In the index leg: established post-thrombotic syndrome (PTS) or previous symptomatic DVT within the last 2 years.
* Limb-threatening circulatory compromise.
* PE with hemodynamic compromise (i.e., hypotension).
* Inability to tolerate catheter procedure due to severe dyspnea or acute systemic illness.
* Allergy, hypersensitivity, or thrombocytopenia from heparin, r-tPA, or iodinated contrast, except for mild-moderate contrast allergies for which steroid pre-medication can be used.
* Known significant bleeding risk, or known coagulation disorder (including vitamin K antagonists with INR \> 2.0 and platelet count \< 100 000/mm3)
* Severe renal impairment (estimated GFR \< 30 ml/min).
* Active bleeding, recent (\< 3 mo) GI bleeding, severe liver dysfunction, bleeding diathesis.
* Recent (\< 3 mo) internal eye surgery or hemorrhagic retinopathy; recent (\< 10 days) major surgery, cataract surgery, trauma, CPR, obstetrical delivery, or other invasive procedure.
* History of stroke or intracranial/intraspinal bleed, tumor, vascular malformation, aneurysm.
* Severe hypertension on repeated readings (systolic \> 180 mmHg or diastolic \> 105 mmHg).
* Pregnant, lactation or parturition within the previous 30 days (positive pregnancy test, women of childbearing age must be tested or use a medically accepted method of birth control).
* Recently (\< 1 mo) had thrombolysis.
* Life expectancy \< 6 months or chronic non-ambulatory status.
* Participating in any other investigational drug or device study or previous enrollment in this study
* Inability to provide informed consent or to comply with study assessments (e.g. due to cognitive impairment or geographic distance).
* Any other condition that the investigator feels would place the patient at increased risk if the investigational therapy is initiated

Answer: B