Phases of a Clinical Trial

• ​​In Phase I trials, researchers test a new drug or treatment in a small group of people (20-80) for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
• In Phase II trials, the study drug or treatment is given to a larger group of people (100-300) to see if it is effective and to further evaluate its safety.
• In Phase III trials, the study drug or treatment is given to large groups of people (1,000-3,000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.

Benefits of participation

How do clinical trials work?

Informed Consent
Informed consent is the process of providing potential participants with the key facts about a clinical trial before they decide whether to participate. The process of informed consent continues throughout the study. To help someone decide whether or not to participate, members of the research team explain the details of the study.

Placebo
Typically, clinical trials compare a new product or therapy with another that already exists to determine if the new one is as successful as, or better than, the existing one. In some studies, participants may be assigned to receive a placebo (an inactive product that resembles the test product, but without its treatment value). Comparing a new product with a placebo can be the fastest and most reliable way to demonstrate the new product’s therapeutic effectiveness.

Randomization
Randomization is the process by which two or more alternative treatments are assigned to volunteers by chance rather than by choice. This is done to avoid any bias with investigators assigning volunteers to one group or another.  The results of each treatment are compared at specific points during a trial, which may last for years. When one treatment is found superior, the trial is stopped so that the fewest volunteers receive the less beneficial treatment.

Single-or double-Blind Studies
​In single-or double-blind studies, also called single- or double-masked studies, the participants do not know which medicine is being used, so they can describe what happens without bias. “Blind” (or “masked”) studies are designed to prevent members of the research team or study participants from influencing the results. This allows scientifically accurate conclusions. In single-blind (“single-masked”) studies, only the patient is not told what is being administered. In a double-blind study, only the pharmacist knows; members of the research team are not told which patients are getting which medication, so that their observations will not be biased. If medically necessary, however, it is always possible to find out what the patient is taking.