Immune dysregulation in COVID-19 infection includes suppression of adaptive but hyperactivation of innate immune system.

Hypercoagulability combined with endotheliitis and hyperinflammation results in significant incidence of pulmonary microvascular thrombosis.

Aggressive prophylactic anticoagulation strategy is likely to be effective in sick patients in preventing thrombosis and improving outcome.

Clinical and laboratory biomarker of disease severity will help to identify who will benefit from combination of antiviral, anti inflammatory and anticoagulation drugs.

Urgent international collaboration is necessary to run large trials to find which drugs and in what combination will be most effective in treating COVID-19 patients.