STATISTICS OF PAPERS PRESENTED AT ASCO: WHAT ARE THE CHARACTERISTICS OF PHASE 2 AND PHASE 3 TRIALS IN BREAST CANCER PRESENTED AT ASCO IN THE PAST 5 YEARS?

Introduction: The ASCO Annual Meeting is the largest and most important clinical oncology conference in the world. Each year, more than 30,000 healthcare professionals attend and an average of 4,200 abstracts are presented, providing a source of publications and knowledge for the oncology community. GOALS: Analyse the characteristics of phase 2 and phase 3 breast cancer trials presented at ASCO Annual Meeting from 2018 to 2022 to assess potential bias in their selection. Methods: We performed a retrospective and descriptive analysis of all phase 2 and phase 3 breast cancer trials presented in ASCO Annual Meeting from 2018 to 2022. We analyzed characteristics such as first author country of origin, multinationality, primary endpoint sought, proportion of positive and negative studies, and proportion of original trials versus post-hoc/exploratory analyzes in the papers shown. Results: From 2018 to 2022, a total of 21,985 abstracts were presented at ASCO Annual Meeting, including 1,871 on breast cancer, with 169 phase 2 and 3 clinical trials. Of the 169 trials, 65 (38.5%) first authors were from the United States, 44 (26.03%) were from the European Union, and 31 (18.34%) were from China. 60 studies (35.5%) were multinational. 50.3% of the trials were phase 2 and 49.7% were phase 3. The primary endpoints most frequently targeted in the phase 3 trials were progression-free survival or disease-free survival (66 trials – 39.05%), followed by pathologic complete response (26 trials – 15.4%), followed by overall survival (16 trials – 9.5%). We found that among phase 3 studies, a higher proportion of studies had a positive outcome (p with statistical significance) with a ratio of 60.71% positive to 39.3% negative. 40.5% of the phase 3 studies were exploratory analyzes or post-hoc analyzes of original studies. Conclusion: The northern hemisphere predominates in the publication of phase 2 and phase 3 studies. The surrogate endpoints of disease-free survival and progression-free survival are most frequently sought. Finally, we found a higher proportion of positive studies, which raises the hypothesis that there is a bias in the selection of papers.