Title: Clinical trial availability and receipt of guideline concordant care among adolescents and young adults (AYAs) with acute lymphoblastic leukemia

Abstract

Abstract BACKGROUND: Adolescents and young adults (AYA: 15-39y) with acute lymphoblastic leukemia (ALL) face poor survival with minimal historical improvement compared to younger patients, prompting National Comprehensive Cancer Network (NCCN) treatment guidelines for ALL to include AYA-specific recommendations. Our team previously revealed that guideline adherence at NCI Community Oncology Research Program (NCORP) practices was influenced by the model of care delivery (adult, pediatric, mixed) but not by annual AYA ALL volume (Wolfson, JNCI-CS, 2025). Receipt of guideline-concordant care (GCC), however, has not been investigated in the setting of clinical trial availability. Earlier hypothesis-generating work documented superior AYA ALL survival at specialized cancer centers (Wolfson, CEBP, 2017); this was theorized to be driven partly by a clinical trials-oriented culture, but that phenomenon has not been examined. We investigated trial availability among AYAs with ALL at NCORP practices and its association with GCC and facility-level factors. METHODS: We utilized recently reported data from a cross-research base, AYA-specific Cancer Care Delivery study (ACCL16N1CD) to assemble a retrospective cohort of newly diagnosed AYAs with ALL treated at participating NCORP practices between 2012-2016. Methods were reported previously. In brief, NCORP sites abstracted patient data and completed facility-level questionnaires for each “clinical facility” (CF: study-defined entity). A central review committee assessed treatment concordance with NCCN AYA ALL guidelines. Therapeutic clinical trials open at participating NCORP practices (including study dates and locations) were identified via Clinical Trials Support Unit (and ClinicalTrials.gov). We summarized clinical trial availability, enrollment, and GCC by facility and patient characteristics. Using logistic regression, we modeled the odds of trial availability and enrollment (adjusting for facility characteristics and provider specialty) and receipt of GCC (adjusting for trial availability and CF volume). RESULTS: Among 227 AYAs (cohort details: PMID: 40238217), 172 (76%) were eligible for at least one trial at their institution. Trial Availability: A trial for AYA ALL was available at all (100%) pediatric, most (91%) mixed, and half (52%) of adult CFs. The proportion of AYAs eligible for an available trial was higher at pediatric (93%) or mixed (82%) than at adult (51%) CFs (p<0.0001). Trial availability did not differ significantly by diagnosis (T-cell, Ph-negative, Ph-positive; p=0.9) or average annual AYA ALL volume (p=0.5). For the subset of AYAs eligible for an available trial, all trials at pediatric and mixed CFs were cooperative group trials, while at adult CFs 97% of this subgroup were eligible for cooperative group trials and 26% for pharma trials. Most patients at mixed CFs with trials available were observed to be treated by pediatric (72%) rather than adult (28%) oncologists. In multivariable analysis, AYAs had higher odds of having a trial available if they were at pediatric (OR=11.0, 95%CI 4.0-35.5) or mixed (OR=4.0, 95%CI 1.8-9.1) rather than adult CFs, but AYA volume was not statistically significant. Enrollment: Among AYAs with trials available, 48% were enrolled. When they were eligible for an available trial, AYAs had higher odds of enrolling if they were treated by pediatric rather than adult oncologists (OR=22.5, 95%CI 8.5-73.4), while annual volume at the CF was not statistically significant. GCC: Although most (86%) AYAs received GCC, GCC was more common among AYAs who did (92%) vs. did not (67%, p<0.0001) have any trials available. We observed higher odds of GCC if any ALL trials were available at the treating CF both in univariable (OR=7.2, 95%CI 2.8-17.9) and multivariable (OR=4.4, 95%CI 1.2-15.6) analyses adjusting for model and volume. CONCLUSIONS: AYAs with ALL are at higher odds of receiving GCC if there are clinical trials available at the treating facility, regardless of whether they are eligible for a trial. AYAs with ALL at NCORPs have higher odds of having a trial available if treated at a pediatric or mixed (vs. adult) practice and of enrolling on a trial if treated by pediatric (vs. adult) oncology. Strategies to improve GCC for AYAs with ALL should include optimizing clinical trial availability (and by extension disease expertise) across facility models. Next steps will further examine the low enrollment among AYAs with available trials.