Parent willingness to enroll children with acute lymphoblastic leukemia in escalation and de-escalation clinical trials.

12098 Background: Patient and parent willingness to participate in clinical trials has and will continue to be essential to improve care for children with acute lymphoblastic leukemia (ALL). Clinical trials for ALL can involve escalation of therapy (i.e., addition or intensification of chemotherapy or immunotherapy) or in subgroups with excellent prognosis, de-escalation of therapy (i.e., removal of agents or blocks of therapy with aim of minimizing toxicity). Understanding parents’ decision making for trial participation is particularly important in de-escalation trials. We aimed to characterize parent willingness to enroll children with ALL in escalation and de-escalation clinical trials, identify sociodemographic and clinical determinants of willingness, and delineate decision making information needs. Methods: Parents of children currently or previously treated for ALL who are members of the Momcology support and advocacy organization completed an investigator-developed, parent-piloted online survey. Parents were presented with theoretical escalation and de-escalation trial scenarios and completed items about willingness to enroll their child and associated informational needs. Quantitative data were summarized descriptively and Spearman correlations examined associations with sociodemographic and clinical determinants. Qualitative data were analyzed using content analysis. Results: A total of 456 parents responded. Mean child age at diagnosis was 5.5 years [SD = 0.2, range 0-19]; 79% (369) had B-ALL and 17% (78) had T-ALL; and 65% (297) had completed therapy and were alive at the time of survey. Results showed that 22% (99) of parents would consider enrolling their child in a de-escalation clinical trial, 47% (216) would not, and 31% (141) were unsure. Responses for escalation trials (N = 423) were similar, with 21% (90) yes, 42% (179) no, and 36% (154) unsure. There was a significant negative correlation between both parent education level (rho = -0.12, p = 0.013) and annual household income (rho = -0.10, p = 0.047) with willingness to consider de-escalation, but not escalation, trial enrollment. Child age at diagnosis, current treatment status and distance from treatment center were not correlated with willingness. Parent decision making information needs clustered into three overarching domains:1) impact on likelihood of relapse, survival outcome, and late effects, 2) evidence credibility, and 3) applicability to their child’s individual risk profile. Conclusions: Across a large parent sample, substantial hesitation to enroll children with ALL in both escalation and de-escalation trials exists. Sociodemographic factors were associated with de-escalation decision making. Further research is needed to incorporate evidence-based parent decision making support in future ALL trials and to evaluate decision making and correlates in real world scenarios.