Clinical trials rely on the participation of volunteers. Some studies require healthy volunteers and others require people with the condition for which a potential new treatment or adjunct therapy is being explored eg people clinically diagnosed with coeliac disease.
Each trial will have its own set of inclusion and exclusion criteria for recruitment. This may include, but is not limited to geographical location, age, gender, length of diagnosis, severity of reaction to gluten, other medical conditions.
There are several steps that must be taken before a new drug can be licensed. The first stage is to obtain an understanding of the disease process and to identify a target. On average it takes three to five years of laboratory work to produce a potential drug that can be tested in humans. In some cases a drug that has already been licensed for one disease is tested for any benefits and any side effects in another disease.
Following the identification of a drug there can be a further eight to ten years of clinical trials:
- Phase I: Checking for side effects and testing the dosage. Usually about 30 people
- Phase II: Does it work in the people with the condition? The drug is tested against a placebo (non treatment). Usually about 200 people
- Phase III: How effective is it? The drug is tested in hundreds or thousands of people and can then be licensed for medical use.
- Phase IV: How does the drug perform in the long term? This involves following people over a series of years.
In total, it can take an estimated 15-20 years to develop, test and license a new drug.
If you take part in a trial you may be given a new treatment or placebo (non treatment) and most often you and the investigator will not know which you have been given. This is called carrying out the study ‘blind’ and is to prevent the results being affected by knowledge and an expectation to react in a certain way.
Clinical trials for people with coeliac disease will usually involve eating gluten for a short period of time to cause an immune response. Consuming gluten for a short time may make participants feel unwell but it’s unlikely to cause lasting damage. People who have very severe reactions when they eat gluten are often excluded.
Before a clinical trial can go ahead there are legal obligations which must be met.
Participation in a clinical trial is voluntary and Coeliac UK neither promotes participation or non-participation, it is an individual’s decision.
We encourage anyone considering taking part in a clinical trial to not be afraid to ask questions of the investigators and to ensure these have been fully answered to their satisfaction before consenting to take part.
Further general information on clinical trials can be found on the NHS Choices website.