A randomized pilot study using calcitriol in hospitalized COVID-19 patients.

The systemic illness associated with SARS-CoV-2 infection results in hospitalization rate of 380.3 hospitalizations per 100,000 population, overwhelming health care systems. Vitamin D regulates expression of approximately 11,000 genes spanning many physiologic functions that include regulation of both innate and adaptive immune function. We investigate potential benefit of calcitriol therapy given to patients hospitalized with COVID-19. This was an open label, randomized clinical trial of calcitriol or no treatment given to hospitalized adult patients with COVID-19. Subjects were randomly assigned treatment with calcitriol 0.5 μg daily for 14 days or hospital discharge; or no treatment (1:1) at time of enrollment. We enrolled 50 consecutive patients, 25 per trial arm. The change in peripheral arterial oxygen saturation to the inspired fraction of oxygen (SaO2/FIO2 ratio) was calculated on admission and discharge between the groups. The control group had an average increase of +13.2 (±127.7) on discharge and the calcitriol group had an increase of +91.04 (±119.08) (p = .0305), suggesting an improvement in oxygenation among subjects who received calcitriol. Additionally, 12 patients in the control group required oxygen supplementation on admission and 21 of them were discharged on room air. 14 subjects needed oxygen supplementation in the calcitriol group on admission while all 25 were discharged on room air. Other clinical markers showed the average length of stay was 9.24 (±9.4) in the control group compared to 5.5 (±3.9) days in the calcitriol group (p = .14). The need for ICU transfer was 8 in the control group and 5 in the calcitriol group. There were 3 deaths and 4 readmissions in the control group and 0 deaths and 2 readmissions in the calcitriol group. This pilot study illustrates improvement in oxygenation among hospitalized patients with COVID-19 treated with calcitriol and suggests the need for a larger randomized trial.