Glossary of Pharmacology 

Phase IV Clinical Trial

Phase IV clinical trials are studies for drugs that have been approved by agencies like the FDA. This phase occurs once the drug is approved for public use and is typically seen as the first time a drug is truly tested. These phases can also be a form of post-marketing surveillance. While phase III looks at safety more, this phase also looks at post-marketing effectiveness, evaluating components like new risks and optimal doses. 

Phase IV clinical trials are valuable as their observational nature allows drugs to be evaluated in a natural setting. While it is possible to predict the side effects of a drug by using pharmacological mechanisms, further effects only become apparent after marketing. The benefits of a phase 4 trial include being able to study a drugs effect on a large population, and seeing if there are new effects once the drug is spread to a diverse audience around the world.  

Teaching Tips:  

https://www.youtube.com/watch?v=TE1bdTwUgT4 

Linked terms:  Phase I clinical trial, Phase II clinical trial, Phase III clinical trial, Drug safety, Drug intolerance, Pharmacovigilance, Toxicity, NOAEL (No Observed Adverse Effect Level), LOAEL (Lowest Observed Adverse Effect Level) 

Resources:  

Brunton, L. L., Knollmann, B. C., & Hilal-Dandan, R. (Eds.). (2018).Goodman & Gilman’s the pharmacological basis of therapeutics (Thirteenth edition). McGraw Hill Medical.

Suvarna, V. (2010). Phase IV of Drug Development. Perspectives in Clinical Research, 1(2), 57–60. 

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