Analysis of the reasons for screening failure in phase I clinical trials in China: a retrospective study of the clinical trials screening process

Background: To analyze the main reasons for screening failure in the screening process of healthy subjects in phase I clinical trials and coping strategies. Methods: We retrospectively collected data from the screening process of 1,640 healthy subjects in 12 phase I clinical trials conducted between April 2019 and July 2020 at the First Affiliated Hospital of Bengbu Medical College. The reasons for screening failure were statistically analyzed (chi 2 test), and correlation studies were conducted to explore the main factors associated with screening failure. Results: Among the 1,640 healthy subjects, 632 (38.5%) successfully passed screening, and 1,008 (61.5%) failed screening. Abnormal laboratory test results (43.25%), abnormal vital sign examination results (11.81%), withdrawal of informed consent (10.02%), abnormal height/weight examination results (8.33%), and abnormal electrocardiogram (ECG) examination results (5.66%) accounted for 79.07% of the screening failures. Subjects aged 46-57 years were more likely to fail screening than those aged 18-30 or 31-45 years (158/220 vs. 541/893 vs. 309/527, respectively, P=0.002), and males were more likely than females to fail screening (721/1, 133 vs. 287/507, respectively, P=0.007). However, the distance between the subject's residence and clinical trial institution (P=0.491) was not significantly correlated with screening failure. Conclusions: Before trial screening, healthy subjects should be informed of the clinical trial risks and have sufficient time to consider or discuss participation with their family members. In addition, subjects should be informed that they should eat lightly, have adequate rest, and maintain a relaxed state of mind prior to screening. Regarding fluctuations in the normal range of laboratory indicators and ECG examination reports during the screening process, clinicians should determine the medical decision level (MDL) for each indicator. If no clinical significance is identified, then the subject can be included. In terms of sex and age, this study provides reasonable suggestions to further improve project protocols and improve the healthy subject screening success rate.