Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 23 1 2024 02 11 82 96 Mona Talaschian Department of Internal Medicine, School of Medicine, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Maryam Akhtari Tobacco Prevention and Control Research Center (TPCRC), National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran Mahdi Mahmoudi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran AND Research Center for Chronic Inflammatory Diseases, Tehran University of Medical Sciences, Tehran, Iran Shayan Mostafaei 5 Department of Biostatistics, School of Health, Kermanshah University of Medical Sciences, Kermanshah, Iran Mohamadreza Jafary Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Seyyed Mostafa Jalali Clinical Nutrition and Dietetics Department, Faculty of Nutrition Sciences and Food Technology, Shahid Beheshti University of Medical Sciences, Tehran, Iran Kourosh Sadeghi Department of Clinical Pharmacy, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran Keivan Gohari Moghadam Pulmonary Ward, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Hengameh Ansari Tadi Emergency ICU, Shariati Hospital, Tehran University of Medical Sciences, Tehran, Iran Ahmadreza Jamshidi Rheumatology Research Center, Tehran University of Medical Sciences, Tehran, Iran 2022 09 18 2023 10 17 The severe coronavirus disease 2019 (COVID-19) is associated with increased levels of blood interleukin (IL)-6. Therefore, it is hypothesized that modulating the levels or effects of IL-6  could diminish airway inflammation and alter the course of COVID-19. We conducted a controlled, randomized, double-blind clinical trial on hospitalized patients with severe COVID-19 in Iran. The patients were randomly distributed by block randomization to take either standard-of-care (SOC) plus 1 or 2 doses of tocilizumab 8 mg/kg or SOC alone. The endpoint was defined by clinical improvement and discharge. We enrolled 40 patients (20 patients in each group) from 10 July to 10 December 2020. After randomization, 1 patient in the SOC arm and 3 patients in the tocilizumab arm refused to participate and were eliminated from the study. The mean age of participants was 59.62±15.80 in the tocilizumab group (8 women and 9 men) and 63.52±12.83 years old in the SOC group (9 women and 10 men) groups. The number of patients who recovered did not differ significantly between the tocilizumab and SOC groups (12 [70.6%][70.6%] vs. 15 [78.9%]), respectively). Hospitalization rates were also similar between the groups (Log-rank test, p=0.615; hazard ratio, 0.83; 95% C‎‎I [0.‎39–1.78]). The results show that tocilizumab could not be a beneficial agent for treating severe cases of COVID-19 patients and would not significantly improve clinical outcomes. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/3658 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/3658/2028