Table 4.

Post-CAR-T-cell infusion factors and risk for first infection within 28 days using Cox proportional hazards regression

Post-CAR–T-cell infusion variables	Unadjusted HR* (95% CI)	P
CAR–T-cell dose level, cells per kg
2 × 107 vs 2 × 105	3.19 (1.07-9.51)	.038
2 × 107 vs 2 × 106	3.15 (1.24-8.01)	.016
ANC < 500 cells per mm3 on day of infection	2.04 (0.85-4.89)	.11
CRS grade
0 vs 1-3 vs 4-5†	3.38 (1.99-5.73)	<.001
Neurotoxicity grade
0 vs 1-2 vs 3-5‡	1.76 (1.11-2.78)	.015
Tocilizumab use§	3.45 (1.23-9.67)	.019
Corticosteroid use§	1.50 (0.43-5.23)	.5
ICU admission	4.35 (1.78-10.65)	.001

HR, hazard ratio.

^*Data shown are from the univariate model only. CRS was the only significant variable in a stepwise multivariable model. Other baseline characteristics with P < .1 but not significant at the P < .05 level included prior antitumor treatment regimens ≥4. There was collinearity between CAR–T-cell dose level, CRS grade, neurotoxicity grade, tocilizumab use, corticosteroid use, and ICU admission.

^†For each increase in CRS severity category from 0 (none) to grades 1-3 to grades 4-5, there was a 3.38 increase in the hazard of infection.

^‡For each increase in neurotoxicity severity category from 0 (none) to grades 1-2 to grades 3-5, there was a 1.76 increase in the hazard of infection.

^§These were analyzed as dichotomous variables (ie, yes vs no).