Influence of age, sex and tumor type in the likelihood of inclusion in early clinical trials

e15193 Background: Inclusivity in early drug development is essential for achieving consistent and accurate results. Sex-specific differences in biology and pharmacology should be explored as early as possible during clinical development. Lack of inclusion of elderly patients underestimates the risk of toxicity due to comorbidities and polypharmacy, but adolescents and young adult patients (AYAs) are even less represented in clinical trials, leading to slower improvements in survival. Methods: Patients referred for a first consultation to Vall de Hebron Institute of Oncology Early Drug Development Unit between 2019-2021 were analyzed. Clinical variables included: age, sex, primary tumor location, clinical trial inclusion and type of clinical trial. Results: On a total of 1218 pts, a total of 580 (48.53%) were included in at least 1 early clinical trial. The median age of the overall population was 61 y(ranging from 22 to 92), with no differences in pts included (62y) or not(60y) in clinical trials. Elderly patients ( > 75y) were 9.1% of the population referred and achieved a similar rate of inclusion (46.90% vs 49.44%) while AYAs(18 to 29-year-old) represented only 1.47% of pts referred and were only matched to a clinical trial in 33.33% of cases. (Fisher’s p-value = 0.06). Equal proportion of males and females were referred to clinical trials, with the exception of elderly patients (60.17% male) and AYAs(61.11%). the overall population). In the overall population the most common primary tumor locations were colorrectal (24.38%), other gastrointestinal tumors (18.14%) and breast cancer (10.91%). The most common primary tumor location in patients > 75y was colorectal(28.82%), other gastrointestinal tumors(19.81%) and head and neck(14.41%) vs sarcoma(38.88%), CNS(27.77%) and other gastrointestinal(11.1%) in AYA patients. Inclusion rates depending on the type of tumor ranged from 63% to 23%. Patients with genitourinary and gynecologic cancers had a statistically significant higher likelihood of being included in a clinical trial whereas sarcoma and primary CNS tumors had lower chances of being included in a clinical trial. In a binomial multivariant model the only factor predictive of inclusion in a early clinical trial was tumor type, whereas, sex, age group and availability of molecular profiling, was not statistically significant. Conclusions: Elderly patients with cancer and AYAs were referred less frequently to our unit that the overall prevalence of cancer in those populations and in the case of AYA pts the rate of inclusion lagged behind, driven mainly by the tumor types more common in each population.