Tocilizumab Use and Outcomes in Hospitalized COVID-19 Patients During the Initial Pandemic Peak in Peru: A Real-World Retrospective Study

Background: Tocilizumab was used as emergency treatment for COVID-19 in Peru during 2020, before randomized clinical trial evidence supporting its use became available. Documenting real-world experiences of its implementation in resource-constrained health systems provides relevant insights for pandemic preparedness. Methods: Retrospective cohort study of 242 patients hospitalized with COVID-19 who received tocilizumab at seven sites in Peru (March–September 2020). Clinical characteristics, tocilizumab use, and adverse events were described (primary objective). A Cox proportional-hazards model was used as a secondary analysis to explore the association between tocilizumab initiation within the first 3 days of hospitalization (days 1–3) vs. later and all-cause mortality. Results: 79.8% (n = 193) patients were male; mean age was 59.0 years (SD: 13.0); 43.0% died. The median cumulative tocilizumab dose was 400 mg (IQR: 400–600 mg), lower than the currently recommended weight-based regimen (8 mg/kg; maximum 800 mg per infusion); 86.4% received a single dose. In the adjusted Cox model, early tocilizumab use was not significantly associated with mortality (HR: 1.09; 95%CI: 0.67–1.75; p = 0.72). The proportional-hazards assumption was met globally. Adverse events of any cause (not assessed for causality) were recorded during hospitalization in 56 (23.1%) patients; the most frequent MedDRA category was respiratory, thoracic, and mediastinal disorders (n = 16). Conclusions: This Peruvian cohort documents how tocilizumab was used, in terms of timing and dose, during the first pandemic wave in a resource-constrained setting. In the absence of an untreated comparator, these data do not allow inferences on the contribution of tocilizumab to mortality, ICU admission, or adverse events.