Overview

The goal of this clinical trial is to learn if troxerutin works to prevent thrombotic events in mild or severe COVID-19 patients. It will also learn about the safety of troxerutin. The main questions it aims to answer are:

• Does troxerutin lower the number of thrombotic events in participants?
• What medical problems do participants have when taking troxerutin? Researchers will compare troxerutin to a placebo (a look-alike substance that contains no drug) to see if troxerutin works to prevent thrombotic events in COVID-19 patients.

Participants will:

• Take troxerutin or a placebo every day for 7 days.
• Visit the clinic at the first, fourth, seventh and 28th days after enrollment for checkups and tests
• Keep a diary of their symptoms and the number of times of thrombotic events, bleeding events and type II HIT-related thrombocytopenia

Eligibility

Inclusion Criteria:

        As long as the patient meets all of the following conditions, adult patients aged 18 and
        above are eligible for admission:
        ► COVID-19 patients, defined as: positive RT-PCR (upper respiratory tract or lower
        respiratory tract) for SARS-CoV-2.
        Mild COVID-19 patients are defined as:
        Symptomatic patients meeting the case definition for COVID-19 without evidence of hypoxia
        or pneumonia. Common symptoms include fever, cough, fatigue, anorexia, dyspnea, and
        myalgia. Other nonspecific symptoms include sore throat, nasal congestion, headache,
        diarrhea, nausea/vomiting, and loss of smell/taste.
        Severe COVID-19 patients are defined as:
        Adolescents or adults with clinical signs of pneumonia (i.e., fever, cough, dyspnea,
        tachypnea) plus one of the following:
          1. Respiratory rate ≥30 breaths/min
          2. Severe respiratory distress
          3. Oxygen saturation (SpO₂) ≤90% in room air
          4. Progressive deterioration of clinical symptoms with lung imaging showing significant
             progression of lesions (>50%) within 24 to 48 hours.
               -  Written informed consent provided according to Chinese law (by the patient, legal
                  guardian, or deferred consent in emergencies).
        Exclusion Criteria:
        Patients with any of the following conditions will be excluded from the study:
          -  Pregnant or lactating women.
          -  Postpartum (within 6 weeks).
          -  Extreme weight (100 kilograms).
          -  Clinical need for heparin therapy.
          -  Bleeding related to coagulation disorders, acute clinically significant bleeding,
             active gastrointestinal ulcers, or any organic lesions with high bleeding risk.
          -  Platelet count <50 x 10^9/L.
          -  Surgery within the last 15 days, or within 24 hours after spinal or epidural
             anesthesia.
          -  History of intracranial hemorrhage, large ischemic stroke, known intracranial
             malformation or tumor, acute infective endocarditis.
          -  Severe renal impairment (creatinine clearance <30 mL/min).
          -  Iodine allergy.
          -  Long-term use of oxygen supplementation.
          -  Moribund patients or those expected to die during the current hospitalization due to
             underlying disease.
          -  Patients deprived of freedom and those undergoing institutional psychiatric care.
          -  Ward of the state or under guardianship.
          -  Participation in other anticoagulant intervention studies.