%0 Clinical Trial, Phase II %T Absolute neutrophil count clinical trial eligibility criteria for pediatric oncology phase I and phase I/II trials by sponsorship. %A Ruiz J %A Kelly RK %A Aplenc R %A Laetsch TW %A Seif AE %J Pediatr Blood Cancer %V 71 %N 5 %D 2024 May 26 %M 38409529 %F 3.838 %R 10.1002/pbc.30925 %X Normal absolute neutrophil count (ANC) variations, as seen with Duffy-null associated neutrophil count (DANC), are not accounted for in trial eligibility, which may contribute to racial enrollment disparities. We describe ANC eligibility for pediatric oncology phase I/II clinical trials according to primary sponsorship from 2010 to 2023 using ClinicalTrials.gov. Out of 438 trials, 20% were industry-sponsored. Total 17% of trials required ANC ≥1500 cells/μL for enrollment; however, industry-sponsored trials were significantly more likely to require ANC ≥1500 cells/μL than non-industry-sponsored trials (odds ratio 2.53, 95% confidence interval: 1.39-4.62; p < .001). These data suggest laboratory exclusion criteria are one possible mechanism for pediatric clinical trial enrollment disparities.