Phase 4

A study of a treatment that is already approved and in use.

Learning 

What it means

Phase 4 studies happen after a treatment has been approved. They follow how it performs in everyday practice and watch for effects that only appear in larger numbers or over longer periods.

Why it matters if you take part

The treatment being studied is already available, so the question is usually about long-term use, rarer effects, or how it compares in real-world conditions.

Related terms

Trials recruiting now that are Phase 4

136 recruiting trials in our Canadian corpus are Phase 4.

This explains how clinical research works. It is not medical advice and does not describe any specific condition or treatment. Only a trial site can determine whether someone can take part in a study.