How clinical trial safety works

Every UK clinical trial has to be reviewed and approved before it can start. A research ethics committee checks that the study is worthwhile and that the people taking part will be properly protected.

Trials are monitored as they run. An independent committee looks at the safety data and can stop a study early if something doesn't look right.

The medicines regulator (the MHRA) also oversees trials of medicines and devices and inspects the teams running them.