However, and despite not being statistically significant results, the frequency and severity of ICANS found in the group that received siltuximab, either as treatment for tocilizumab refractory CRS, or as first-line treatment, could be more closely related to patient’s characteristics, TB, CRS grade and CAR T-cell product used (tandem CD19/CD22), rather than to the administration of the drug itself. This evidence concerns the gene CD19 and tuberculosis.