The information on this page is accurate, but we are still working on the look and feel of this page.

Here are the answers to frequently asked questions about clinical trials. If you have further questions, please email

What is a clinical trial?

A clinical trial is a rigorously controlled test designed to examine the safety and/or effectiveness of drugs, devices, treatments, or preventive measures in humans. Clinical trials follow a strict protocol to ensure that the testing is completed as quickly and safely as possible and accurately answers the questions being asked. Although the start of a clinical trial is cause for optimism it must be remembered that only 20 percent of all studies are successful and therefore they aren’t a guarantee for a treatment.

What do I do if I want to participate in a clinical trial?

Register your interest in taking part in trials with your doctor and remind him or her regularly.

It is also important to join national registries if they are available for your condition. The two main registries currently available in the UK are for Duchenne muscular dystrophy and spinal muscular atrophy. Patients or their parents can fill out an online form to register. For other neuromuscular conditions, registries are in development or are run by clinicians in other countries. You may be able to register with these registries but you might need your doctor to help with this. Links and contact details for all of the registries can be accessed via the TREAT-NMD website.

Finally, you can also directly contact the centre involved in the clinical study. They will get in touch with your local doctor whose involvement is essential.

What are the different phases of a clinical trial?

Phase I is usually quite small and almost always designed purely to assess the safety of the new treatment and how well it’s tolerated. Often phase I studies are done using healthy volunteers.

Phase II can last up to two years. It tests the effectiveness of a treatment on a larger number of patients. Participants are sometimes divided into groups and the benefit of the drug is compared to a placebo, which could be described as an ‘empty‘ drug. Usually the patients don’t know whether they have been given the real drug or the placebo. The trial is then known as a ‘blinded study’. Phase II trials are sometimes divided into phase IIa and phase IIb.

Phase IIa is specifically designed to determine the best dose of the drug.

Phase IIb is specifically designed to study how well the drug works at the dose determined in the phase IIa study.

Phase III involves a larger number of patients and follows the same process as Phase II. This step can take two to three years. The aim is to gain a more thorough understanding of the effectiveness and benefit of the drug.

Phase IV evaluates the long term risks and benefits of the drug once it’s available on the market.

Why participate in a clinical trial?

People have different reasons. Some want to have a more active role in their own health care or would like to benefit from new research developments before they become more widely available. They should keep in mind that although the start of a clinical trial is a very promising sign, it isn’t a guarantee for a treatment. One other advantage is that people taking part in clinical trials are followed up using even more stringent assessments than usual, even after the trial has finished. This close attention could result in better management of the condition.

Clinical trials inevitably carry a risk though and so it is very important that an informed decision is made. Understanding the details of the clinical trial process and the impact it has on participants and their families is essential before a final commitment is made.

What are the risks and disadvantages of taking part in a trial?

Many patients are understandably eager to get involved in clinical trials. However it is very important that they understand what is involved. They should discuss the study in detail with the trial nurse or doctor before giving their consent to take part.

The main disadvantage is that studies often involve multiple and frequent visits to hospital. This is obviously not always easy or practical. Procedures could be painful, for example injections and biopsies and, of course, there is always the risk of an adverse reaction to the treatment. Participants in a trial also have to keep in mind that the treatment they receive might not provide any direct benefit for them – there is a chance they might be given a very low dose of the drug, or even a placebo.

Who can participate in a clinical trial?

All clinical trials have guidelines about who can take part. The factors that allow someone to participate in a clinical trial are called ‘inclusion criteria’ and those that disallow someone from participating are called ‘exclusion criteria’. These criteria are based on such factors as age, gender, the type and stage of a disease, previous treatment history, and other medical conditions. Before joining a clinical trial, a participant must qualify for the study.

Inclusion and exclusion criteria are not used to reject people personally, instead they:

  • Keep the participants safe, for example another underlying condition could make participation in the trial dangerous.
  • Help ensure that the researchers are able to produce reliable results and therefore get the treatment to market as quickly as possible so that the wider population can benefit.
  • Increase the reliability of the results by ensuring that everyone taking part has similar symptoms at the beginning of the trial. Otherwise it is difficult for the researchers to interpret the results because they won’t know if the reason one patient responded to treatment and another didn’t is due to the drug or differences in their condition to begin with. This is especially helpful in the early phases of a clinical trial when there are only few participants.

In most circumstances, people who wish to participate in a clinical trial will find it easier if they live relatively near the team of people who are conducting the research, because they need to be monitored frequently. The clinical trial organisers will usually reimburse travel costs (within reason).

What do I need to know before I enrol in a clinical trial?

You should know as much as possible about the clinical trial and feel comfortable asking the members of the healthcare team questions about it, the care expected while in a trial, and the cost of the trial.

The following questions might be helpful for the participant to discuss with the healthcare team:

  • What is the purpose of the study?
  • Who is going to be in the study?
  • Why do researchers believe the experimental treatment being tested may be effective?
  • Has it been tested before?
  • What kinds of tests and experimental treatments are involved?
  • How do the possible risks, side effects, and benefits in the study compare with my current treatment?
  • How might this trial affect my daily life?
  • How long will the trial last?
  • Will hospitalisation be required?
  • Who will pay for the experimental treatment?
  • Will I be reimbursed for other expenses?
  • What type of long-term follow up care is part of this study?
  • How will I know that the experimental treatment is working?
  • Will results of the trials be provided to me?
  • Who will be in charge of my care?

Is Muscular Dystrophy UK funding any clinical trials?

We granted funding to a clinical trial led by Dr Rosaline Quinlivan to test a new drug for people with McArdle’s disease.

In the past we funded a clinical trial that looked into the long-term benefit of Vitamin C for people with Charcot-Marie-Tooth disease. Read about the results of this trial.

In addition to the studies funded directly through our research programme, we provide administrative and managerial support for the setting up of clinical trials. We are helping the muscle centres in London and Newcastle with the administrative burden that comes with clinical studies by providing funding for clinical trial coordinators. We also help to facilitate groups of scientists and clinicians to work together – this is essential for larger clinical trials. An example is the ‘MDEX consortium’ which was set up to carry out the UK exon skipping trials – we played a vital role in bringing together the scientists involved and securing the £1.6m funding from the Department of Health for the initial trial.

Keep in touch
- Enter Your Location -
- or -