C-reactive protein and ferritin levels and length of intensive care unit stay in patients with B-cell lymphomas treated with axicabtagene ciloleucel.

Objective/background: Chimeric antigen receptor (CAR) T-cell is an effective therapy in relapsed/refractory large B-cell lymphomas that, due to its unique toxicities, often requires escalation of care to the intensive care unit (ICU) setting. C-reactive protein (CRP) and ferritin are serum inflammatory markers associated with onset and persistence of CAR T-cell-related toxicity.

Methods: We retrospectively analyzed 34 patients treated with axicabtagene ciloleucel (axi-cel) who were divided into two groups: patients requiring admission to the ICU during initial hospitalization (n = 13, 38%) and those who did not (n = 21, 62%). Primary objective was to examine possible relationships between serum ferritin and/or CRP levels with the need for, and length of, ICU stay between these groups.

Results: All 13 patients admitted to the ICU developed cytokine release syndrome (CRS) and 11 of them also developed neurotoxicity (NT). Of the 21 patients in the non-ICU group, 18 developed CRS and 5 patients developed NT. Grade of CRS and NT were higher in ICU versus non-ICU patients (p = .03 and .001, respectively). There was no correlation between CRP levels at time of ICU admission and length of ICU stay (correlation of 0.41, p = .17). Yet, there was an association between serum ferritin levels and length of ICU stay (R = 0.73) which did not reach statistical significance (correlation of 0.21, p = .49).

Conclusion: Notwithstanding the limitations of the small sample size, our study suggests that an elevated ferritin level at the time of escalation of medical care may be possibly indicative of anticipated prolonged ICU hospitalization in patients treated with axi-cel. A large multicenter study is certainly needed to confirm this observation.