Abstract Introduction: Clinical trials serve as pivotal sources for evidence-based medicine, wielding substantial influence within the medical and scientific community. In recent years, heightened attention has been directed towards encouraging greater female involvement and advancing their representation across various domains of the medical field. Female oncologists tend to focus more over breast cancer as a subspeciality and focused practice. Consequently, this observational study seeks to assess the present status of gender equity in leading breast cancer clinical trials, with the aim of identifying potential concerns and mitigating future risks of bias. By delving into this analysis, we can shed light on the current landscape and pave the way for improved inclusivity and fairness in breast cancer research. Methodology: To examine the portrayal of female principal investigators (PIs) in breast cancer clinical trials over the past two decades, we conducted a thorough search of breast cancer clinical trials listed on ClinicalTrials.gov. Furthermore, we employed https://gender-api.com to assess the gender of each PI and calculate the experience in the medical field of the PI by subtracting the PI graduation year from the year of conducting the clinical trial. In addition, we gathered pertinent details concerning the PIs and the clinical trials, and subsequently subjected the data to univariate analyses to detect any noteworthy distinctions between male and female PIs. Results: Over the span of the past twenty years, a total of 9,145 cancer clinical trials were conducted, with 1,127 (12.32%) focusing specifically on breast cancer. Through our rigorous efforts, we managed to gather comprehensive information about the principal investigators (PIs) in 788 (69.92%) of these clinical trials. Notably, we discovered that 419 (53.17%) of these trials were led by female investigators. Upon scrutinizing the characteristics of the PIs, we observed several significant distinctions between male and female PIs. Female PIs exhibited a lower median age (57.0 vs. 60.0) and possessed less medical experience (17 vs. 22 years) compared to their male counterparts (P< 0.001). Furthermore, we found a substantial divergence in the funding sources for the clinical trials between the genders. Female-led trials received a lower percentage of industrial funding (13.1% vs. 24.2% for males, P< 0.001) but showcased a significantly higher percentage of university funding (38.7% vs. 28.0% for males, P< 0.001). Most of the clinical trials led by female PIs were categorized as phase 2 trials (82.8% vs. 66.8% for males) and were conducted in single centers (61.2% vs. 52.6% for males), demonstrating a noteworthy statistical difference (P< 0.001) in both cases. However, no statistically significant disparities were found between male and female PIs in terms of termination rates, publication rates, or the type of intervention utilized in the clinical trials. Furthermore, the ratio of females PI wasn’t different throughout the time as the liner regression model estimated effect was -0.009 with P= 0.065. Conclusions: The study shows the great effort done by female researchers, even though they have lower age, experience, and support from the industrial companies and lower opportunity to have bigger multicenter clinical trials, they still manage to have equivalent rate of termination and publication of the clinical trials showing their capability to lead clinical trials and the need to be supported to maintain the gender equity in leading the breast cancer clinical trials. However, female involvement in other cancer sites might be different and needs to be looked at. Citation Format: Abdulrahman Alhajahjeh, Ghayda’ Bader, Basil Abdin, Taima’ Bader, Saji Aweidah, Layla El-Amayreh, Hikmat Abdel-Razeq. Advancing Gender Equity: A Closer Look at Women's Representation in Leading Breast Cancer Clinical Trials [abstract]. In: Proceedings of the 2023 San Antonio Breast Cancer Symposium; 2023 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2024;84(9 Suppl):Abstract nr PO1-10-12.