Clinical trials are research studies that test how well new medical approaches work in people. Each study answers scientific questions and tries to find better ways to prevent, screen for, diagnose or treat a disease.
Clinical trials can take years, thousands of dollars and many participants to complete, but they are the most effective way to bring new drugs and therapies to the public.
This is the brainstorming period—a time when researchers develop an idea and refine the therapy they want to test.
Frequently, animal testing is used at this point, to investigate the safety and effectiveness of the treatment.
The research protocol spells out every detail of the study: who can participate, who can’t, the dosage for any drugs involved, how to monitor possible side effects and how the resulting data will be evaluated. It provides the roadmap that will guide the trial over the next several years.
This is the first time the therapy is used on humans—a trial by fire that defeats many studies.
If the translational trial is successful, the official trial begins. It’s broken into three phases: Phase I—Dose-finding, Phase II—Safety and activity, and Phase III—Comparative efficacy.
Phase I, dose-finding, is the process of discovering the best way to deliver the therapy.
The group of participants is kept fairly small, and, depending on the study, test subjects can be healthy or people suffering from life-threatening diseases. Researchers want to see how people react to the treatment and if there are any side effects.
In Phase II—safety and activity—the scope of the study increases. There are now 100 or more participants and the trials take place in several different locations.
Many trials at this point pit their experimental therapy against an accepted treatment plan to see how it compares; this is called a randomized controlled trial.
Participants are divided into a control group and a study group. The control group is given the new treatment and the study group is given either the current accepted treatment or, if one doesn’t exist, no treatment at all.
Both groups are observed closely and any side effects or improvements are noted.
A randomized controlled trial is known as an interventional type of trial. In contrast, there are also trials that are purely observational.
Observational trials concentrate on health issues that affect large groups of people, such as a specific age group or ethnicity. Researchers search for patterns, but no medical intervention is made.
Phase III—comparative efficacy—increases the scope of the testing yet again, this time including thousands of participants around the country or around the world. Side effects are carefully monitored and the dosage is meticulously calibrated.
Throughout all three phases, data on the results of the trial is collected—lots of it. And this stage is when this information is analyzed.
During the data analysis, doctors and biostatisticians review the results of the trial to determine if they are “medically compelling and statistically significant.”
At last, when the data has been analyzed and the therapy is found to be effective and safe, it is sent to the FDA—the Food and Drug Administration—for approval.
This is the last hurdle. With the FDA’s okay, the therapy can now to be released to the world.