With the advent and development of new and novel therapeutics, more and more questions arise about clinical trials. What are they exactly? What types of trials are there? How many phases are there? What happens in each phase?
While the topic is more complex and involved that we can fully cover here, the hope is that this can answer some of the more basic questions.
So, what are Clinical Trials? In short, they are voluntary research studies that are conducted in people and designed to answer various questions about the safety and/or efficacy of drugs, vaccines, or other therapies.
We are all probably familiar with the idea of there being different phases in Clinical Trials. We will often hear the terms Phase I or Phase II for example. But before we get to that, did you know there are also different types of trials?
Let’s review those now.
- Preventative Trials: These are for testing new medications and vaccines. This type of trial is used to determine if the medication or vaccine in question can lower someone’s risk of disease.
- Screening Trials: These trials focus on finding ways to detect and diagnose diseases before patients experience the symptoms of those diseases. Typically the point here is to see if earlier detection will lower the risk of disease.
- Diagnostic Trials: These are similar to Screening Trials but they focus on detection and diagnosis after the patient begins to experience symptoms
- Treatment Trials: The are the trials that most of us probably think of when it comes to trials. These test new medications, medical devices, and other therapies in order to collect and determine safety and effectiveness.
- Genetic Studies: These are done to learn new ways to predict various genetic disorders earlier.
Now, let’s move on to the different phases of a trial.
Phase One: I should point out that prior to entering into a Phase One Trial, you should have collected enough laboratory data to indicate that your product is worth investigating further. During Phase I a small group of participants that represent those that would be ideal patients for your product (a medication or therapy) actually use the product and report any results including side effects or other symptoms back to you. All information must be recorded.
Phase Two: If the results from Phase One show that your product was safe for use, you can now test it on a larger number of patients. If the product is a medication for example, appropriate dosage should have been determined in Phase One. If, after Phase Two, you have tested the product on a large enough group and the FDA is reasonably sure that it can be effective on a larger scale, you can move the Phase Three.
Phase Three: In this phase your product is tested on larger groups of people and you will monitor the side effects and efficacy for each patient. If your product is a medication, you can utilize placebos which act as a control. Essentially, they help reduce the effects of any perception or expectations that your patients may have.
Phase Four: If you’ve made it this far, congratulations! Your product, be it a medication, therapy, surgery, or medical device has received FDA approval. Studies done during this phase focus on the longer-term effects of your product and gathering more data.
Again, this is a very simplified overview. Any intention to take a product into trials requires a lot of work, years in many cases, and huge amounts of research. This is in no way a definitive guide. I do hope it helps explain the differences in the types of trials and the basics of the trial phases.
Written by Sean
Senior Scientific Support Specialist, Lonza Pharma-Bioscience Solutions at Lonza
