Terminated clinical trials: A 5-year global evaluation of trends and underlying causes
Kaviya Manoharan, Juanna Jinson, Dinesh Kumar Chinnadhurai, Melvin GeorgeAbstract:
CONTEXT:
Termination of clinical trials is an inherent part of clinical research that gives rise to scientific, ethical, and financial concerns. ClinicalTrials.gov defines a terminated trial as a study that was halted prematurely and will not resume, and one where participants are no longer being examined or receiving intervention.
AIMS:
This study aimed to identify terminated clinical trial trends and assess the reasons for the same.
SETTINGS AND DESIGN:
Data on clinical trials that were terminated between January 1, 2018 and December 31, 2022 were collected from ClinicalTrials.gov. Trials were sorted based on year of termination, phase, therapeutic area, and population age group.
METHODOLOGY:
Information was manually scrutinized to identify the reasons for termination. Analysis and representation were done using Microsoft Excel. A total of 11,035 trials were terminated during the specified period, and a rising trend was observed. Overall, 25.4% of trials were terminated owing to safety concerns. 12.5% of the trials did not report the reason for termination. Most terminations were in phase 2 (31.91%). The therapeutic area with the largest number of terminated trials was hematology (13.7%), followed by oncology (9.0%). 94.2% and 14.1% of trials were conducted on the adult and pediatric populations, respectively.
CONCLUSIONS:
The rising trend in trial terminations, particularly in phase 2 and within hematology/oncology, underscores the need for better accrual strategies and safety monitoring. Increasing transparency in reporting termination reasons is essential to optimize resource utilization in future clinical research.