Impact of age on clinical trial availability for AYAs with cancer: A time-trend analysis.

1534 Background: Low participation of adolescents and young adults (AYAs, age 15-39 yrs at diagnosis) in cancer clinical trials (CCT) limits their access to novel therapies and hinders the ability to study disease biology and age-specific toxicities. Patient age may be an important barrier as younger and older AYAs may be excluded depending on the trial’s focus. In 2017, the American Society of Clinical Oncology and Friends of Cancer Research issued a joint statement encouraging removal of age as a CCT eligibility criterion unless there is specific biological rationale. To evaluate the impact of this statement, we undertook this analysis of CCT availability for AYAs. Our primary objective was to compare the number of CCT available for AYAs, overall and by tumor types, from 2019-2023 vs previously published data from 2007-2018. The availability of early phase trials and study sponsor was also assessed. Methods: We identified CCT registered on ClinicalTrials.gov from January 2019 to July 2023 enrolling patients with 10 malignancies relevant for AYAs (Hodgkin lymphoma, anaplastic large cell lymphoma, melanoma, extracranial germ cell tumors GCT, medulloblastoma, thyroid cancer, Ewing sarcoma, osteosarcoma, rhabdomyosarcoma RMS, and synovial sarcoma). Trials were categorized as adult (≥18 yrs), transitional (patients < or ≥18 yrs), or pediatric (<18 yrs). Transitional trials with an age range 12-18 to <40 yrs were defined as AYA specific trials. Early phase included phase 1 and 1/2 trials; late phase included phase 2/3 and 3 trials. Trial availability from 2007-2018 was identified from a prior analysis by deRojas et al in 2019 (PMID:32337483). The proportion of trials in each category was compared between 2007-2018 and 2019-2023 using z-tests. Results: There were 1071 eligible trials registered on Clinicaltrials.gov: 840 (78%) adult, 226 (21%) transitional, and 5 (0.5%) pediatric. Four trials were AYA-specific. Compared to the prior 10 years, the proportion of transitional trials did not change overall (19% vs 21%, p=0.24) or within any disease. Whereas the proportion of trials available at age 17 has not significantly changed overall (20% vs 21%; p=0.48) or within any disease, the proportion of trials available at age 18 significantly increased (95% vs 98%; p<0.001) in aggregate and specifically for Ewing sarcoma (93% vs 100%; p=0.003), GCT (96% vs 99%; p=0.002), medulloblastoma (86% vs 98%; p=0.006), RMS (87% vs 98%; p=0.007) and thyroid cancer (92% vs 98%; p=0.01). Time trends for transitional trials by phase and sponsor are summarized (Table). Conclusions: Availability of transitional trials for AYAs has not increased, particularly for those <18 yrs. The 18-yr-old age limit continues to be an obstacle in CCT availability and enrollment. Table: see text