Clinical evidence supports a direct correlation between IL-6 levels and the severity of CRS in patients receiving CAR-T cell therapy.399,402 An anti-IL-6 receptor antagonist, tocilizumab, has demonstrated significant efficacy in controlling CRS and was approved by the FDA for this purpose in 2017.416–420 In addition, corticosteroids have proven effective in managing treatment-related toxicities.416 For patients who show an inadequate response to IL-6 receptor blockade, prompt administration of corticosteroids is recommended. This evidence concerns the gene IL6 and congenital rubella syndrome.