To investigate the status of clinical trials registered on ClinicalTrials.gov on diseases in the list of rare diseases in China and analyze the registration characteristics.

All clinical trials involved in the list of rare diseases in China were searched on ClinicalTrials.gov from inception to April 5th, 2022. The relevant information of clinical trial registration was collected, and WPS Office was used for data analysis.

A total of 12 904 rare disease-related clinical trials were screened out, and the overall trend was increasing year by year. The information of clinical trial stages was missing a lot, and the sample size was mainly 0~100 cases. The types of trials were mainly interventional studies (9 042 trials, 70.1%) and observational studies (3 760 trials, 29.1%). There were three main statuses of trials: completed (6 467 trials, 50.1%), recruiting (2 388 trials, 18.5%), and unknown status (1 207 trials, 9.4%). The number of drug therapy trials was the largest (5 992 trials, 46.3%). The countries/regions participating in clinical trials were mainly developed countries in Europe and the United States. All of the top three single/multi-center rare disease-related clinical trials were conducted in European and American countries. There were a small percentage of clinical trials conducted in China (460 trials, 3.6%), but the proportion of single center-clinical trials was the highest (260 trials, 56.5%). The research institutions were mainly universities and medical institutions, and in China they were mainly medical institutions (358 trials, 77.8%). The sponsoring institutions were mainly European and American countries. The design of rare disease-related clinical trials was mainly non-randomized, open label and parallel allocation of therapeutic regimens. The outcome indicators were mainly related to safety and efficacy.

The development of clinical trials of rare diseases in China is on the rise, but there is a big gap with European and American countries. We should establish a systematic research and development incentive mechanism and introduce relevant laws and regulations as soon as possible to promote the high-quality development of clinical trials of rare diseases.