Rational Use of Tocilizumab in Critically Ill COVID-19 Patients: A Two-Center Observational Study in the Intensive Care Unit

Abstract

Background: Tocilizumab (TCZ) is a key treatment for severe COVID-19 but poses risks due to immunosuppression and limited evidence. Concerns about misuse and limited supply necessitate a thorough assessment. This study investigates the utilization patterns and appropriateness of tocilizumab use in critically ill COVID-19 patients.

Methods: Over nine months, this prospective, cross-sectional, observational study evaluated TCZ use in adult COVID-19 patients at the intensive care unit (ICU) of two referral hospitals in Isfahan, Iran, from February 2022 to April 2023. Data on TCZ dosing, duration, and concomitant treatments were collected to evaluate the rational use of TCZ as the primary outcome. Clinical outcomes, APACHE scores, inflammatory markers, and adverse effects were monitored on days 3 and 5 post-TCZ administration. We aimed to explore the associations between appropriate TCZ administration and both clinical and laboratory outcomes as secondary endpoints. Statistical analyses were set at P < 0.05.

Results: After excluding 10 patients due to incomplete data from the 118, 108 patients were analyzed for TCZ use. The mean age was 64.3 years, with 58.3% males. Notably, 39.8% of patients did not meet TCZ indication criteria, and only 7.5% received rational use of TCZ according to clinical guidelines regarding indication, dose, and dosing intervals. CRP levels significantly decreased after TCZ treatment (P < 0.001). The rational prescription group had higher APACHE scores five days post-treatment (P = 0.05), and appropriate TCZ use was significantly more common among intubated patients (P = 0.02).

Conclusion: While rational use correlated with higher APACHE scores, no significant differences in other outcomes were observed, possibly due to sample size. Tocilizumab’s mechanism in reducing inflammation and CRP is well-established. Still, limitations include incomplete data on out-of-hospital prescriptions and patients who needed but did not receive TCZ, which necessitate further investigations.