Transparency shortcomings can undermine confidence in the safety and efficacy of vaccines. This study assesses the publication status of 95 clinical trials of 3 COVID-19 vaccines developed by Chinese companies that received a World Health Organization Emergency Use Listing (EUL) and have been marketed globally. We searched trial registries and the scientific literature to assess current trial status and the public availability of results. After excluding 2 withdrawn trials, we found that at least 62/93 trials (67%) involving 307,933 patients had verifiably been completed or terminated. Only 44 of those 62 trials (71%) had published results in a peer-reviewed journal; none had tabular summary results available on a trial registry. The results of 18/62 (29%) verifiably completed or terminated trials remained unpublished. The trial status information stated in trial registries was often incorrect. Our findings reveal a substantial gap between the disclosure practices of the 3 Chinese companies and global best practice benchmarks. Transparency and global public trust in Chinese biopharmaceutical products could be improved by aligning Chinese legal disclosure requirements with those prevalent in more mature markets, or by the voluntary adoption of stronger transparency practices by Chinese companies.

The authors have declared no competing interest.

https://osf.io/4f9k7

This study did not receive any funding

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