Objective: Abnormal immune responses play a fundamental role in coronavirus disease 2019 (COVID-19). Overexpression of proinflammatory cytokines, especially tumor necrosis factor-alpha (TNF-α), is considered as one of the important factors in the development of the disease. Several monoclonal antibodies have been proposed to inhibit the function of TNF-α. Therefore, this study investigated the possible effects of a biosimilar Adalimumab named CinnoRA ®, a TNF-α inhibitor, on patients with severe COVID-19.

Materials and Methods: This randomized clinical trial was conducted on 80 patients infected with severe COVID-19. After confirming the disease, patients were selected with simple random sampling and divided into two groups, including patients receiving subcutaneous injections of 80 mg of adalimumab and standard treatments (case group) and those only treated with standard treatments (control group). The demographic features, clinical symptoms, laboratory findings, and other information were recorded during hospitalization.

Results: No patients in the case group required ventilatory support and only one case died due to COVID-19, whereas three cases of the control group needed ventilatory support and died during hospitalization. Although there were differences in the values of peripheral blood oxygen saturation (SpO2), erythrocyte sediment rate (ESR), C-reactive protein (CRP), and hospitalization duration between subjects treated with and without adalimumab, these alterations were not statistically significant.

Conclusion: The treatment with adalimumab failed to exert significant changes in clinical and laboratory parameters participating in the recovery and outcome of COVID-19.