• SARS-CoV-2 test (by local evaluation) positive - Symptom severity and general risk of decompensation warrants, in the opinion of the treating clinician, admission to/care in an intensive care unit setting - Patient or legally authorized representative (LAR) able and willing to provide written informed consent - No contraindication to receiving anticoagulation - At least one D-dimer value ≥2 times local ULN (within 72 hours of hospital admission)

Patients who meet ANY of the following criteria are not eligible for inclusion: - Moribund patient not expected to survive 24 hours - ICU length of stay > 24 hours prior to initiation of frunexian infusion - Existing venous thromboembolism - Known immune compromise (HIV/AIDS, chemotherapy, chronic corticosteroid therapy, transplant patient, etc.) - Active cancer diagnosis - Pregnant, lactating, or parturient woman - bodyweight <40kg - hemoglobin <8.0 g/L in the last 72 hours - platelet count <50 x 109/L in the last 72 hours - known fibrinogen <1.5 g/L (if testing deemed clinically indicated by the treating physician prior to the initiation of anticoagulation) - known INR >1.8 (if testing deemed clinically indicated by the treating physician prior to the initiation of anticoagulation) - patient already on therapeutic anticoagulation at the time of screening (low or high dose nomogram UFH, LMWH, warfarin, or any regular dose of a direct oral anticoagulant) - patient on dual antiplatelet therapy, when at least one of the agents cannot be stopped safely - history of spontaneous intracranial bleeding; gastrointestinal bleeding requiring hospitalization and/or transfusion within prior 3 months - major surgery within prior 30 days - known bleeding within the last 30 days requiring emergency department presentation or hospitalization - known history of a bleeding disorder of an inherited or active acquired bleeding disorder - recent (<48 hours) or planned spinal or epidural anesthesia or puncture - anticipated transfer to another hospital that is not a study site within 72 hours - enrollment in other trials related to anticoagulation or antiplatelet therapy - use of pneumatic compression devices for thromboprophylaxis - Failure to meet ALL Inclusion Criteria