IL6 and COVID-19: Since the JAK-STAT pathway mediates the effect of several cytokines, including IL-6, which are raised in severe COVID-19, JAK inhibitors have been proposed as a potential therapeutic option for severe COVID-19.8, 9 Baricitinib also has moderate inhibitory activity against TYK2 and genetic data support a causal link between high TYK2 expression and life-threatening COVID-19.10