Clinical efficacy of intravenous immunoglobulin therapy in critical ill patients with COVID-19: a multicenter retrospective cohort study

ObjectiveCoronavirus disease 2019 (COVID-19) outbreak is a major challenge all over the world, without acknowledged treatment. Intravenous immunoglobulin (IVIG) has been recommended to treat critical coronavirus disease 2019 (COVID-19) patients in a few reviews, but the clinical study evidence on its efficacy in COVID-19 patients was lacking. Methods325 patients with laboratory-confirmed critical COVID-19 were enrolled from 4 government-designated COVID-19 treatment centres in southern China from December 2019 to March 2020. The primary outcomes were 28- and 60-day mortality, and the secondary outcomes were the total length of in-hospital and the total duration of the disease. Subgroup analysis was carried out according to clinical classification of COVID-19, IVIG dosage and timing. ResultsIn the enrolled 325 patients, 174 cases used IVIG and 151 cases did not. The 28-day mortality was improved with IVIG after adjusting confounding in overall cohort (P = 0.0014), and the in-hospital and the total duration of disease were longer in the IVIG group (P < 0.001). Subgroup analysis showed that only in patients with critical type, IVIG could significantly reduce the 28-day mortality, decrease the inflammatory response and improve some organ functions (all P < 0.05); the application of IVIG in the early stage (admission <= 7 days) with a high dose (> 15 g per day) exhibited significant reduction in 60-day mortality in the critical-type patients. ConclusionEarly administration of IVIG with high dose improves the prognosis of critical-type patients with COVID-19. This study provides important information on clinical application of IVIG in the treatment of SARS-CoV-2 infection, including patient selection and administration dosage and timing.