https://www.fiercebiotech.com/research/melatonin-stem-cells-resea...

https://www.fiercebiotech.com/research/melatonin-stem-cells-researchers-step-up-unconventional-approaches-to-covid-19

The article stated
"Mesoblast has also completed a study of the product in 60 patients with chronic obstructive pulmonary disease, which shares some of the same inflammatory biomarkers with COVID-19, the company said. That study, which has not yet been published, showed “significantly improved pulmonary function” in patients with elevated inflammatory biomarkers, the company said in a statement."

Also Children have much higher levels of Melatonin than adults. I wonder if that is why children are not being affected as much with covid-19 virus.
Interesting if there is a protective factor between melatonin and covid-19.