https://www.scientificamerican.com/article/coronavirus-vaccine-u-k-trial-restarts-but-scientists-question-lack-of-transparency/

The UK trial of a leading coronavirus vaccine, which was abruptly halted last week because of safety concerns, restarted on Saturday after the university conducting the trial said an independent committee found that it was safe to do so.

The University of Oxford and pharmaceutical company AstraZeneca paused enrolment in the global trials of their vaccine candidate on 6 September, after a person participating in the UK trial experienced an adverse reaction.