In association with the approval of the first chimeric antigen receptor (CAR) T-cell therapy, on August 30, 2017, the FDA also accelerated the approval of a new indication as an orphan drug for tocilizumab (Actemra; Genentech), a humanized interleukin-6 receptor antagonist, for the treatment of patients aged ≥2 years with CAR T-cell–induced severe or life-threatening cytokine release syndrome (CRS).
This new indication for tocilizumab was based on a retrospective analysis of data from clinical trials evaluating the efficacy of the drug in 45 adults and pediatric patients who received tocilizumab with or without high-dose corticosteroids, for the treatment of severe or life-threatening CRS. Overall, 31 (69%) patients achieved a response, which was defined as the resolution of CRS within 14 days of the first tocilizumab dose. No more than 2 doses of tocilizumab were used in the trial. No tocilizumab-related adverse events were reported in the study. The results from a second trial of 15 patients with CAR T-cell–induced CRS were used to confirm the resolution of CRS within 14 days of tocilizumab therapy.
The common side effects associated with tocilizumab include upper respiratory tract infections, headache, hypertension, and injection-site reactions. Serious side effects include an increased risk for serious infections and certain cancer types, tears in the stomach, thrombocytopenia, neutropenia, hepatitis B infection, serious allergic reactions, and central nervous system problems.