Potential usefulness of pentoxifylline, a non-specific phosphodiesterase inhibitor with anti-inflammatory, anti-thrombotic, antioxidant, and anti-fibrogenic properties, in the treatment of SARS-CoV-2.

Although most patients with coronavirus disease 2019 (COVID-19) have a good prognosis, in some cases, the disease progresses rapidly, and the mortality rate is high. Some evidence suggests that infection with the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) produces a 'cytokine storm', which is related to acute respiratory distress syndrome or multi-organ dysfunction leading to physiological deterioration and death. It is important to highlight the state of hypercoagulability that can be triggered, involving microvascular thrombosis and vascular occlusive events, which are relevant to such poor outcomes. At present, no specific antiviral drug or vaccine is available for SARS-CoV-2 infection, and current research is aimed at preventing and mitigating damage to the target organs, mainly the lungs. In seeking therapies for patients with COVID-19, immunomodulators, cytokine antagonists and early anti-coagulation therapies have been tested in attempts to reduce the mortality rate. Pentoxifylline, a non-specific phosphodiesterase inhibitor widely used to improve the rheological properties of blood, has beneficial anti-inflammatory properties and can significantly reduce the serum levels of pro-inflammatory cytokines such as interleukin (IL)-6, IL-1, tumour necrosis factor-alpha, C-reactive protein and other immunoregulators. It has also been found to exert anti-thrombotic, antioxidant and anti-fibrogenic actions. These properties could help to prevent or mitigate the inflammatory response and hypercoagulability that develop with SARS-CoV-2 infection, decreasing multi-organ dysfunction manifesting primarily as acute lung injury.