High-Dose Intravenous Immunoglobulin as a Therapeutic Option for Deteriorating Patients With Coronavirus Disease 2019

Cao, Wei; Liu, Xiaosheng; Bai, Tao; Fan, Hongwei; Hong, Ke; Song, Hui; Han, Yang; Lin, Ling; Ruan, Lianguo; Li, Taisheng

As a result, high-dose IVIg at 0.3-0.5 g per kg weight per day for five days was used in our patients as a potent and safe immune modulator. The dose of IVIg was determined based on well-established practice in immune modulation therapy for other diseases, including neuromuscular disorders, autoimmune thrombocytopenic purpura, etc. [6, 7] , with a consideration of potential cardiac or renal impairment in severe COVID-19 patients. None of the 3 patients reported any adverse events. All patients were clinically improved shortly after the administration, with their temperature back to normal in 1-2 days and breathing difficulties alleviating in 3-5 days. Confounding factors did exist, including the use of different antivirals in 2 of the 3 patients at various time points and a short course of steroids in patient 3. Moreover, in patient 2, valsartan, an angiotensin receptor 1 blocker (AT1R), had been used for treating hypertension. As angiotensin-converting enzyme 2 (ACE2) has been identified as the major receptor-binding domain of SARS-CoV-2 [8, 9] , there has been a hypothesis that higher expression of ACE2 after being chronically medicated with AT1R may protect SARS-CoV-2-infected patients against acute lung injury rather than putting them at higher risk, though this currently remains unproven [10] . Nevertheless, from the timeline and patterns of disease course in these 3 patients, it is most probable that high-dose IVIg played the leading role in their recovery.