Conclusions
In this prematurely stopped trial, we did not reach a conclusion for the primary endpoint due to lack of statistical power. In sensitivity analyses censoring observations after rescue therapy with tocilizumab or increased dose of corticosteroids, the point estimate is comparable with previous trials. We observed a significant interaction between vaccination status and treatment group on occurrence of SAEs, although this is based on a post hoc analysis and should be interpreted with caution. This potential safety signal should be explored in other trials and real-world studies, before influencing treatment decisions.