Study Enrollment and Demographics
In total, 25 sites have participated in the Registry, with 23 currently active sites who have IRB approval in reliance with subject enrollment under the CHOP IRB. Site activation was staggered ranging from 2016 to 2022 after completion of regulatory requirements. All sites are academic medical centers, and the number of enrolled subjects per site ranges from 1 to 135 (Figure 1 ). Specific enrolling sites are listed in Figure 1 legend and includes sites across 15 states. As of December 1, 2022, a total of 717 subjects are enrolled. As the Registry’s ongoing open enrollment format allows for temporarily incomplete data, here we report the 683 subjects with the minimum required dataset entered at time of data lock for this analysis. Table 1 summarizes the cohort demographics. The median reported age at diagnosis was 22 months (interquartile range (IQR) 5, 86 months).