Randomized Controlled Clinical Trial to Investigate Effects of Vitamin K2 in COVID-19

Coronavirus disease 2019 (COVID-19) is caused by the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). While the majority of people recover after mild symptoms, a portion of COVID-19 patients develops respiratory failure. Coagulopathy and thromboembolism are prevalent in severe COVID-19, and these factors are associated with decreased survival. Coagulation is an intricate balance between clot promoting and dissolving processes in which vitamin K plays an essential role. Elastin is a major component of dynamic tissues such as lungs and arteries, and elastin calcification stimulates elastin degradation and vice versa. The vitamin K-dependent Matrix Gla Protein (MGP) protects elastin from both calcification and degradation. Although technically feasible, direct quantification of blood vitamin K levels is not an appropriate method to assess overall vitamin K status due to differences in bioavailability and half-life time between the two naturally occurring vitamin K forms (vitamin K1 and K2). Measuring inactive levels of vitamin K-dependent proteins in the circulation is the method recommended by most experts, as it represents the systemic availability of both vitamin K1 and K2. Dp-uc (dephospho uncarboxylated, i.e. inactive) MGP and proteins induced by vitamin K absence (PIVKA-II) both inversely correlate with vitamin K status and can be used as surrogate markers of total vitamin K status. Recently, we found a severely reduced vitamin K status (as quantified by dp-ucMGP) in COVID-19 patients compared to controls. In COVID-19 patients, low vitamin K status was also associated with poor outcome (defined as the need for invasive ventilation or death), accelerated elastin degradation (quantified by plasma (iso)desmosine (DES) a byproduct of elastin degradation). Based on these finding and previous studies, we hypothesize that improving vitamin K-status by vitamin K supplementation could have favorable effects on pulmonary damage and coagulopathy in COVID-19.