Double-blind, Randomized, Placebo-controlled Trial With N-acetylcysteine for Treatment of Severe Acute Respiratory Syndrome Caused by Coronavirus Disease 2019 (COVID-19)

Abstract

Abstract Background A local increase in angiotensin 2 after inactivation of angiotensin-converting enzyme 2 by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) may induce a redox imbalance in alveolar epithelium cells, causing apoptosis, increased inflammation and, consequently, impaired gas exchange. We hypothesized that N-acetylcysteine (NAC) administration could restore this redox homeostasis and suppress unfavorable evolution in patients with coronavirus disease 2019 (COVID-19). Methods This was a double-blind, randomized, placebo-controlled, single-center trial conducted at the Emergency Department of Hospital das Clínicas, São Paulo, Brazil, to determine whether NAC in high doses can avoid respiratory failure in patients with COVID-19. We enrolled 135 patients with severe COVID-19 (confirmed or suspected), with an oxyhemoglobin saturation <94% or respiratory rate >24 breaths/minute. Patients were randomized to receive NAC 21 g (~300 mg/kg) for 20 hours or dextrose 5%. The primary endpoint was the need for mechanical ventilation. Secondary endpoints were time of mechanical ventilation, admission to the intensive care unit (ICU), time in ICU, and mortality. Results Baseline characteristics were similar between the 2 groups, with no significant differences in age, sex, comorbidities, medicines taken, and disease severity. Also, groups were similar in laboratory tests and chest computed tomography scan findings. Sixteen patients (23.9%) in the placebo group received endotracheal intubation and mechanical ventilation, compared with 14 patients (20.6%) in the NAC group (P = .675). No difference was observed in secondary endpoints. Conclusions Administration of NAC in high doses did not affect the evolution of severe COVID-19. Clinical Trials Registration Brazilian Registry of Clinical Trials (REBEC): U1111-1250-356 (http://www.ensaiosclinicos.gov.br/rg/RBR-8969zg/).