Clinical trial

How it is used

Trials run in phases: Phase I, small and often in healthy volunteers, for safety; Phase II for effect and dose; Phase III, in large patient groups, to confirm benefit; Phase IV after approval. People enrol in or take part in a trial. Hospital pharmacists often manage trial medicines.

Example sentences

1. She is taking part in a clinical trial of a new diabetes drug.

2. The clinical trial was stopped early because the benefit was so clear.

Common collocations

• take part in a clinical trial
• run a clinical trial
• Phase III clinical trial
• clinical trial results

Related terms

• placeboA dummy treatment that looks like the real medicine but contains no active ingredient, used in clinical trials for comparison with the drug being tested.
• double-blindDescribes a trial in which neither the participants nor the researchers know who is receiving the real treatment and who is receiving a placebo or comparator.
• randomized controlled trialA study in which participants are put into groups by chance, one receiving the treatment being tested and another a placebo or standard treatment, so results can be fairly compared.
• informed consentA person's voluntary agreement to take part in research or to have a treatment, given after the purpose, risks, benefits and alternatives have been clearly explained.
• endpointThe main outcome a clinical trial measures to decide whether a treatment works, such as survival, the number of heart attacks or a change in blood pressure.

More terms: Clinical Trials and Drug Development

• preclinical