The development of an investigational treatment is divided into steps called ‘phases’. The investigational treatment generally passes through each phase successfully before it can continue on to the next.
PHASE 1 3-50 people
Usually healthy volunteers but can be people with the disease
Safety and how the body breaks down the study treatment
PHASE 1/2 OR 2 10-60 people
People with the disease
Safety and effectiveness (the ability of a study treatment to produce a beneficial change)
PHASE 3 12-150 people
People with the disease
Long-term safety and effectiveness compared to current standard of care or a placebo (a sugar pill)
Once the studies are complete, the study information along with other information on the drug is submitted to and reviewed by a government agency (e.g., the United States Food and Drug Administration, or FDA). If the data shows the study treatment is safe and effective, it may be approved for use by prescription.