TOcilizumab and Covid-19 : Risk of Severe INfection

SARS-CoV2 is responsible for a pandemic that has been evolving for approximately 18 months. The virus' capacity for dissemination and its virulence are responsible for significant morbidity and mortality. The initial lack of knowledge of the pathogen and of the pathophysiology underlying the potential severity of the disease, particularly in the respiratory tract, led to numerous therapeutic attempts in this emergency context, centered on the control of an obviously exaggerated inflammatory response. A large number of studies remained of insufficient quality to lead to relevant and applicable conclusions. Secondly, the benefit of corticosteroid therapy has been demonstrated in two trials. Although Dexamethasone remains the only corticosteroid to improve survival, these results have reinforced the hypothesis of the interest of treatments reducing the inflammatory response, particularly cytokine. The widespread use, in the absence of scientific data, of interleukin-6 receptor inhibitors (Sarilumab and Tocilizumab) has been structured around studies whose results remain uncertain to this day because of the heterogeneity of the population treated and the results observed. A possible survival benefit seems to emerge for resuscitation patients who have not yet required invasive ventilation, the other situations being probably associated with the absence of effect or even the potential danger of this treatment. Tocilizumab is notably associated in the literature with the risk of secondary infections and mucosal healing abnormalities, favoring bleeding complications and digestive perforations. The objective of this study is to evaluate the risk of digestive complications (hemorrhage, perforation, diverticulitis) and infectious complications related to the use of Tocilizumab according to the severity of the patients.