The purpose of this study is to determine whether a higher dose of low molecular weight heparin (enoxaparin 40 mg b.i.d.) is superior than the standard prophylaxis dose (enoxaparin 40 mg o.d.) in reducing thromboembolic events in COVID-19 patients.

Coronavirus disease-19 (COVID-19 ), which is caused by SARS-CoV-2 infection, are apparently at high risk of venous thromboembolism (VTE), as a consequence of activation of the hemostatic system which, in the most severe cases, can also be associated with the formation of microthrombi and clinically relevant disseminated intravascular coagulation. Concerns about the efficacy of thromboprophylaxis with standard doses of low-molecular-weight heparin (LMWH) has been raised. Therefore, LMWH at higher doses than those recommended for thromboprophylaxis is used in some hospitals, although no evidence exists yet of higher efficacy of high doses compared to standard prophylactic doses. This practice might as well increase the risk of major bleeding. The investigators designed a randomized trial comparing standard prophylactic dose of subcutaneous enoxaparin (40 mg o.d.) with higher dose (40 mg b.i.d) with the aim of testing whether high-dose thromboprophylaxis is more effective than standard dose in preventing VTE in COVID-19 patients.

Inclusion Criteria:

• All-comers patients aged >=18 years and admitted to hospital with laboratory-confirmed SARS-CoV-2 infection

Exclusion Criteria:

• Patients admitted directly to an intensive care unit;
• Estimated creatinine clearance <15 ml/min/1.73m2;
• Patients needing anticoagulant for prior indication;
• Participants involved in other clinical trials;
• Any other significant disease or disorder which, in the opinion of the investigator, may either put the participants at risk because of participation in the trial, or may influence the result of the trial, or the participant's ability to participate in the trial.

Open label