Ten-year patterns of women participating in treatment clinical trials for cancer.

e13754 Background: Ensuring adequate participation of women in cancer research is a national priority. Sex contributes to differences in cancer risk, treatment response, and the risk of adverse reactions to anticancer agents. Thus, the NIH issued a policy for the Inclusion of Women and Minorities as Subjects in Clinical Research that became an important review criterion for grants. To understand this policy’s impact in cancer research, we analyzed women's participation in clinical trials at our institution over the last 10 years. Methods: In this retrospective observational study, we determined the proportion of women participating across cancer treatment clinical trials at the Abramson Cancer Center (ACC) at the University of Pennsylvania from 2012 - 2022. Deidentified data was available from > 170,000 participants in ACC human subjects research. We included those aged > = 18 with a confirmed cancer diagnosis or pre-cancerous condition and enrolled in a cancer treatment clinical trial. We excluded cancers that predominantly affect one sex. We compared women participation rates at the ACC to national sex incidence rates for each cancer and to sex incidence rates in our catchment area. Results: From 2012 – 2022, the percentage of women participating in non sex-specific cancer studies at ACC was 54% +/- 5.7% (mean +/- SD, range 43.3% to 66.0%). Among all cancers analyzed across 9 disease areas and over the ten-year period, women participation was similar to national incidence, with three exceptions: ENT and Neurologic (women participated relatively more >5%), and Thyroid (relatively less ≤5%). Compared to the percentage of women with cancer in our catchment area, women participated more in Neurologic and less for Pancreas and Thyroid. Finally, compared to the percentage of patients at the ACC, women participated less only for Liver (Table 1). Conclusions: When subdivided by cancer type, and excluding sex-specific tumors, women were neither over-represented nor under-represented in clinical trials compared to patients cared for at the ACC, in our catchment area, or nationally. Because the percentage of women varies by cancer type, women participation should not necessarily be 50%. Hence, in line with the NIH’s efforts, women at our center were well-represented in treatment clinical trials for cancer, beyond just trials for sex-specific diagnoses such as breast and gynecological cancers. Cancer Type (Grouped) National 2012-2022 (Difference) Catchment Area 2015-2019 (Difference) ACC cancer patients 2022 (Difference) ACC trial participants 2012-2022 ENT 19.9 (+5 ) 28.9 (-4) 26.1 (-1.2) 24.9 GI 45.4 (-0.1) 45.1 (+0.2) 46.3 (-1) 45.3 GU 30.2 (-0.2) 30.6 (-0.6) 31 (-1) 30.0 Liver 28.2 (-4.8) 26.8 (-3.4) 34.3 ( -10.9 ) 23.4 Lung 48.5 (+4.1) 52.6 (0.0) 52.6 (0.0) 52.6 Melanoma 41 (+4.2) 41.1 (+4.1) 43.5 (+1.7) 45.2 Neurologic 43.8 (+6.6 ) 36.2 ( +14.3 ) 50.9 (-0.5) 50.4 Pancreas 48 (-3) 50.3 ( -5.3 ) 49 (-4) 45 Thyroid 75.1 ( -9.1 ) 73.6 (-7.6 ) 69.3 (-3.3) 66