Helping you understand the language of clinical trials
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The types of clinical trial and the phases
Clinical trials are being spoken about more than ever before. Yet that can be understandably confusing, often leaving people with many questions. What are the phases? What happens at each stage? What is the difference between a trial and a study? Are there different types of each or are they all the same?
We answer those questions, and others, here. But before we take a deeper dive into clinical trials, let’s make sure we’re all on the same page:
- Clinical trials allow scientists and clinicians to conduct research to assess the safety and tolerability of both existing and investigational treatments, as well as diagnostics.
- Clinical trials should not be confused with preclinical research, which takes place before trials begin.
- There are different types of clinical trials and studies that are each run differently.
- Clinical trials are completed in the same series of steps called phases.
By the end of this blog, we hope that you’ll feel confident in what clinical trials are and how they’re run. If you do have any questions about clinical trials, you can speak to your healthcare provider.
The types of clinical trials
Clinical trials show scientists, clinicians, and regulatory bodies, like the U.S. Food and Drug Administration (FDA) and similar agencies in other countries, if an investigational treatment works better than an existing treatment, what the side effects are, and what happens to the drug in the body. The type of treatment and condition the trial is investigating affects how scientists and doctors run it. There are two main types of trial:
- Interventional trials – patients are put into treatments groups so the research team can compare the results of different treatments.
- Observational studies – the research team observes the participants taking part but doesn’t influence what treatments they have. This means that people taking part in the study receive treatments and healthcare advice from their regular clinicians like normal.
Within these two categories are specific study and trial designs that enable scientists and clinicians to answer a wide range of questions. We won’t go into the details of the different designs here as there are many. The key thing to remember is the distinction between interventional trials versus observational studies.
The phases of clinical trials
Now we’ve covered types of clinical trials, let’s take a look at the different phases. Everyone who takes part in a clinical trial is a volunteer, whether they are healthy volunteer or a patient with a specific condition. So, what are the different phases and how do they differ? Let’s take a look…
Find out more about taking part in a clinical trial
The type of trial and phase you participate in will depend on your condition, the type of treatment being developed and what trials are currently available to you. You’ll likely find that some studies may offer compensation for volunteers, and/or reimbursement for costs associated with any travel that might be required. The compensation can vary by study and by the phase of the study.
One thing that remains consistent is that in whatever trial or study you participate in, the clinicians and researchers involved will closely monitor your health throughout the trial, with your safety being their top focus. You can find out more about importance of clinical trials and the protocols that are followed in our blog, “The significant contribution of clinical trials in bringing the very latest healthcare treatments to humanity.”
If you’re looking to explore alternative treatment options, speak to your clinician to see if you could benefit from participating in a clinical trial to have the chance to receive an investigational treatment.