Clinical Trial Phases, Explained in Plain Language

Every approved medicine in Canada went through the same journey: a sequence of carefully designed research phases, each answering a different question.

Phase 1: Is it safe?

Small groups, healthy volunteers in most cases, and a focus on safety and dosage.

Phase 2: Does it work?

A few hundred participants who have the condition. Researchers look for evidence of benefit and continue to monitor safety.

Phase 3: Is it better?

Hundreds to thousands of participants. The investigational treatment is compared against the current standard of care. Most studies on JoinAStudy.ca are Phase 2 or Phase 3.

At every phase, an independent Research Ethics Board reviews and monitors the study, and participants may leave at any time.