In spite of an earlier assumption that intravenous immunoglobulins (IVIG) could improve outcomes by reducing inflammation-mediated lung injury, a latest clinical trial showed no such effect. According to the results of a randomised, placebo-controlled, phase-3 trial done in 146 patients at 43 centres in France between April and October published in The Lancet Respiratory Medicine on November 11, IVIG did not significantly reduce ventilator-free days at day 28 in patients admitted to the intensive care unit for COVID-19 linked moderate-to-severe acute respiratory distress syndrome ARDS. 

The lead authors of the report stated that across the whole population — including patients older than 65 years, patients who were obese (body-mass index ≥30 kg/m2), and those who had received corticosteroid — IVIG had no effect on the duration of invasive mechanical ventilation and mortality.