ABSTRACT
Objective: The purpose of this study was to characterize real-world studies (RWSs) registered at ClinicalTrials.gov to help investigators better conduct relevant research in clinical practice. Methods: A retrospective analysis of 944 studies was performed on February 28, 2023. Results: A total of 944 studies were included. The included studies involved a total of 48 countries. China was the leading country in terms of the total number of registered studies (37.9%, 358), followed by the United States (19.7%, 186). Regarding intervention type, 42.4% (400) of the studies involved drugs, and only 9.1% (86) of the studies involved devices. Only 8.5% (80) of the studies mentioned both the detailed study design type and data source in the "Brief Summary". A total of 49.4% (466) of studies had a sample size of 500 participants and above. Overall, 63% (595) of the studies were single-center studies. A total of 213 conditions were covered in the included studies. One-third of the studies (32.7%, 309) involved neoplasms (or tumors). China and the United States were very different regarding the study of different conditions. Conclusion: Although the pandemic has provided new opportunities for RWSs, the rigor of scientific research still needs to be emphasized. Special attention needs to be given to the correct and comprehensive description of the study design in the Brief Summary of registered studies, thereby promoting communication and understanding. In addition, deficiencies in ClinicalTrials.gov registration data remain prominent.
ABSTRACT
OBJECTIVE: This study aims to comprehensively evaluate the characteristics of clinical drug trials to facilitate the collection of evidence for COVID-19 drug treatments. METHODS: A retrospective analysis of 910 trials retrieved on August 7, 2020. RESULTS: A total of 910 registered clinical trials with at least one drug intervention were evaluated. The number of registrations (32.4%, 295) from the United States accounted for nearly one-third of the total and far exceeded that of other countries individually. Furthermore, the peak number of trials were registered in April (34.3%, 312). Over half of the trials (51.2%, 466) are in the recruitment phase, and only 4.2% (38) of the trials have been completed. The median (interquartile range) estimated enrollment is 127 (59, 365). In 39% (355) of trials, the estimated enrollment is less than 100 participants. A total of 94.5% (790) of the trials use randomization in the allocation, 82.7% (753) use a parallel intervention mode, and 52.2% (475) use masking. A total of 287 drug names have been standardized and mapped. "Hydroxychloroquine" is the leading drug among the registered trials (7.47%, 68). Among the main countries contributing to investigations on "hydroxychloroquine", the United States ranks first with 36.76% (25) of the trials. CONCLUSION: The designs of COVID-19 clinical drug trials have greatly improved in terms of the implementation of randomization and, particularly, blinding methods. In terms of drug reuse, the number of drug types has greatly increased, and hundreds of drugs have been used for efficacy screening. The emergence of large-sample registration trials is expected to address the uncertainty regarding the current clinical efficacy of some drugs.