Phase 1

The aim of these trials is to find:

• The best dose
• If the new treatment is safe

Phase 2

These trials give more information about:

• Safety of the treatment
• If it works or not

 Phase 3

If a Phase 2 trial suggests that the treatment is safe and works, then the treatment is tested in a Phase 3 trial. Main aims are:

• To see if the new treatment is better, worse or the same as other options.
• To provide more information about the safety of the treatment.

 Phase 4

These trials are done after the government approves the treatment for use. 

• In Australia, this is monitored by the Therapeutic Goods Administration (TGA).
• Phase 4 trials continue to look at the safety of the new treatment and how well it works.