New Voices for Research: Clinical Research Trials

Tuesday, January 5, 2010

Clinical Research Trials

Getty Images: Mallory Cecil, 2009 NCAA Division I Women's Singles Tennis Champion

When I was in high school, I played tennis competitively. I loved to win, as all athletes do, but it was the games that I lost that taught me the most. Through defeat, I could see what strategies worked, and more importantly, which didn’t. Taking that one step further, I’d ask why that strategy failed, come up with a new and improved way to work that strategy, and try it at the next competition. If it worked, perfect. If it failed, the process repeated, but eventually I won the game. The scientific process works the same way.

Basic research can take years to develop a therapy that shows promise for humans. However, one of the great things about research is that even a failure is a success. Everything we do teaches us something, and advances our understanding of the field we’re interested in.

Once that strategy is perfected at the level of basic research, it’s time to test it on humans. Clinical research trials are exactly that: taking a basic research finding and applying it to a human population while asking a very specific health related question.

There are two types of clinical research trials: observational and interventional. Observational trials are just how they sound; you observe a population and ask a question about them without giving them anything. For example, one might ask what percentage of military veterans are afflicted with post-traumatic stress disorder.

Interventional trials are experiments in which the researcher intervenes with the population, giving them a drug or therapy to test its effectiveness. For example, a researcher might want to test if a new drug designed to decrease panic attacks could be helpful to military veterans with PTSD.

Before a drug can be available to the entire population, it needs to undergo interventional clinical research trials to test both its safety and efficacy. The clinical research paradigm is set up so that this is accomplished in three steps, called Phase I, II, and III.

Each phase has a slightly different question in mind, building on the findings from the previous study. The overall goal is to determine the usefulness and safety of the drug, while determining the proper dose and expected side effects. At the end of the three phases, the collected data is sent to the FDA so they can decide if the drug is safe enough.

Once the drug is approved by the FDA, trials may continue into Phase IV. It is during these trials (often observational) that researchers examine longer-term effects of the drug, as well as its cost effectiveness as compared to other approved treatments (commonly referred to as comparative effectiveness research).

Here's a simple chart that summarizes the differences between these phases: