Ranieri VM, Pettila V, Karvonen MK, et al. - The intent of this study was to ascertain the efficacy and adverse events of IFN-β-1a in patients with moderate to severe ARDS. A multicenter, randomized, double-blind, parallel-group was performed at 74 intensive care units in 8 European countries recruiting a total of 301 adults with moderate to severe acute respiratory distress syndrome (ARDS) according to the Berlin definition between December 2015 and December 2017. Individuals were assigned randomly to receive an intravenous injection of 10 μg of IFN-β-1a (144 patients) or placebo (152 patients) once daily for 6 days. Compared with placebo, intravenous IFN-β-1a administered for 6 days resulted in no significant difference in a composite score that included death and the number of ventilator-free days over 28 days among adults with moderate or severe ARDS. In the management of ARDS, these effects do not support the use of IFN-β-1a.