Endotracheal application of ultraviolet A light in critically ill severe acute respiratory syndrome coronavirus-2 patients: A first-in-human study

Background Promising preclinical experiments show that, under specific and monitored conditions, ultraviolet-A (UVA) exposure reduces certain bacteria, fungi, and viruses including coronavirus-229E without harming mammalian columnar epithelial cells. We aimed to evaluate the safety and effects of UVA therapy administered by a novel device via endotracheal tube in critically ill subjects with SARS-CoV-2 infection. Methods Five newly intubated mechanically ventilated adults with SARS-CoV-2 infection, with an endotracheal tube size 7.5mm or greater, were treated with UVA for 20 minutes daily for 5 days, and followed for 30 days. Results Five subjects were enrolled (mean age 56.6yrs, 3 male). At baseline, all subjects scored 9/10 on the WHO clinical severity scale (10=death) with predicted mortality ranging from 21 to 95%. Average log changes in endotracheal viral load from baseline to day 5 and day 6 were -2.41 (range -1.16 to -4.54; Friedman P=0.002) and -3.20 (range -1.20 to -6.77; Friedman P<0.001), respectively. There were no treatment-emergent adverse events. One subject died 17 days after enrollment due to intracranial hemorrhagic complications of anticoagulation while receiving extracorporeal membrane oxygenation. The remaining subjects clinically improved and scored 2, 4, 5, and 7 on the WHO scale at day 30. In these subjects, the slope of viral load reduction during UVA treatment correlated with the slope of improvement in clinical WHO severity score over time (Spearman rho=1, P<0.001). Conclusion In this first-in-human study, endotracheal UVA therapy under specific and monitored settings, was safe with a significant reduction in respiratory SARS-CoV-2 viral burden over the treatment period. Trial Registration ClinicalTrials.gov # NCT04572399 . Key Messages What is the key question? Can endotracheal narrow-band UVA therapy be a safe and effective treatment for severe SARS-CoV-2 infection? What is the bottom line? Under specific and monitored settings, endotracheal UVA light therapy may be an effective treatment for SARS-CoV-2 infection. Endotracheal UVA light therapy appears to be well tolerated in critically ill patients with SARS-CoV-2 infection. Why read on? This is the fist-in-human trial of internal UVA therapy using a alternative novel approach to combat COVID-19.