Comparative Effectiveness of Baricitinib Versus Tocilizumab in Hospitalized Patients With COVID-19: A Retrospective Cohort Study of the National Covid Collaborative

COVID-19 treatment guidelines recommend baricitinib or tocilizumab for the management of hospitalized patients with COVID-19. We compared the effectiveness of baricitinib vs. tocilizumab on mortality and clinical outcomes among hospitalized patients with COVID-19. Multicenter, retrospective, propensity-weighted cohort study using a target trial emulation approach. The National COVID Cohort Collaborative (N3C), which is the largest electronic health records data on COVID-19 in the United States. The setting included 75 hospitals. Adults who were hospitalized for COVID-19. Newly initiated on baricitinib or tocilizumab. Our primary outcome was 28-day mortality. We used propensity scores with inverse probability of treatment weights (IPTWs) to control bias and confounding while comparing treatments. Among 10,661 individuals included in the study, 6,229 (58.4%) received baricitinib and 4,432 (41.6%) tocilizumab. Overall, the mean age of the cohort was 60.0 ± 15.1 years, 6429 (60.3%) were male, and 19.2% received invasive mechanical ventilation. After IPTW adjustment, baricitinib use was associated with lower 28-day mortality (odds ratio [OR], 0.91; 95% CI, 0.85-0.98) and hospital (OR, 0.88; 95% CI, 0.82-0.94) mortality compared with tocilizumab. Baricitinib was also associated with shorter hospital length of stay (incident rate ratio, 0.92; 95% CI, 0.90-0.94) and lower rates of hospital-acquired infections (OR, 0.86; 95% CI, 0.75-0.99), although no difference in ICU length of stay was noted between the two groups. In this large, diverse cohort of U.S. hospitalized adults with COVID-19, baricitinib was associated with significantly lower 28-day mortality, hospital mortality, shorter hospital length of stay, and less hospital-acquired infections compared with tocilizumab.