IL6 and congenital rubella syndrome: Tocilizumab and steroid-refractory ICANS and CRS remain key barriers to the optimal management of patients with CAR T. Additionally, although steroids have shown efficacy in the management of ICANS, some reports suggest that tocilizumab may precipitate ICANS in high-risk patients due to its inability to penetrate the blood–brain barrier and transient increase in systemic and CNS IL-6 levels following tocilizumab administration.2 4 10–12 Therefore, corticosteroids remain a key element for the management of ICANS.