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How clinical trials work

A clinical trial is a rigorously controlled test designed to examine the safety and/or effectiveness of medicines, devices, treatments, or preventive measures in humans. Clinical trials follow a strict protocol which describes the aims, design and organisation of the trial. The protocol also provides information on the background and reasons for a trial, and outlines the study plan. The plan must be carefully designed to ensure safety of the participants, as well as to answer specific research question(s). The clinical trial protocol describes:

  • the type of participant for the trial
  • the schedule of tests
  • what procedures will be involved in the trial
  • medications and dosages
  • the duration of the trial

It must be remembered that only about 20 percent of all clinical trials are successful, and therefore they aren’t a guarantee that a treatment will become available.

What are the different phases of a clinical trial?

Phase I – aims to test the safety of a new treatment and see how well it’s tolerated. Often phase I studies are done on a small number of volunteers (usually healthy).

Phase II – tests how well a treatment works on a larger number of patients.

Phase III – involves a larger number of patients and follows the same process as phase II. The aim is to gain a more in-depth understanding of how effective and beneficial the treatment is.

Phase IV – takes place once the new treatment has passed all the previous phases and has been given a marketing licence. A marketing licence means the medicine can be made available on prescription. The safety, side effects and effectiveness of the medicine continue to be studied while it’s being used in practice.

How to participate in a trial?

Speak to your doctor to let them know that you are interested in taking part in trials.

When planning a clinical trial, it is very important that suitable participants can be identified and contacted quickly. The MTM and CNM Patient Registry makes it easier and faster to find patients who are potentially eligible for clinical research and trials.  Patients (or parents of patients under the age of 18) can join the registry online.

You can also directly contact the centre involved in the clinical trial, if you know it. They will then get in touch with your local doctor whose involvement is essential.

To find out about the current clinical trials in Myotubular or Centronuclear Myopathy, use the search box at:

Why do people participate in clinical trials?

Different people have different reasons for taking part in a clinical trial.

There is currently no cure for Myotubular or Centronuclear Myopathy, but research is being carried out into possible treatments and many people want to have a more active role in this, with the additional hope of benefiting from new research developments as soon as possible. It is important to be aware that although the start of a clinical trial is a very promising sign, it can be a long process and it isn’t a guarantee for a treatment at the end of it.

Another potential 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.

It is important to remember that clinical trials can carry risks as well. It is crucial to be well informed before making a decision to take part in a clinical trial.

It is essential to understand the details of the clinical trial process and the impact it has on participants and their families before a final commitment is made.

What are the risks of taking part in a trial?

Many patients are very willing to get involved in clinical trials, however it is very important to understand what is involved. Before committing to take part, they should have a very detailed discussion about the study with the trial nurse or doctor.

The main disadvantage is that studies often involve multiple and frequent visits to hospital, which may not always be easy or practical. Some of the procedures could be painful, for example injections and biopsies, and there is always a risk of adverse reactions 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 (a treatment that has no therapeutic effect, used as a control in clinical trials).

All of these aspects should be discussed in detail with the trial nurse or doctor before committing and giving consent to take part in a trial.

Who can participate in a clinical trial?

All clinical trials have guidelines about who can take part – these are called ‘eligibility’ or ‘inclusion’ criteria and they are listed in the clinical trial protocol.

‘Inclusion criteria’ are factors that allow someone to participate in a clinical trial. ‘Exclusion criteria’ are factors that disqualify someone from participating. These criteria are usually very strict and are based on factors such as age, gender, 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 guaranteed to keep the participants safe. For example, some underlying but unknown conditions could make participation in the trial dangerous. They are used to enable the researchers to produce reliable results, which is essential for the treatment to get to market as quickly as possible so that the wider population can benefit.

Inclusion criteria also increase the reliability of the results by ensuring that everyone taking part has similar symptoms at the beginning of the trial. Without the criteria it would be difficult (if not impossible) for the researchers to interpret the results, because if one patient responded to treatment and another didn’t, they wouldn’t know if was due to the drug or whether it was a result of differences in their condition to begin with. This is especially helpful in the early phases of a clinical trial when there are often only a 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 is informed consent?

Informed consent is when researchers provide potential participants with information about a clinical trial, to help them decide if they want to take part in the trial.

The informed consent process is intended to protect participants and should provide enough information for them to understand the risks of, potential benefits of, and alternatives to the study. In addition to the informed consent document, the process may involve information materials, verbal instructions, question-and-answer sessions, and activities to measure participant understanding.

In general, a person must sign an informed consent document before joining a clinical trial to show that they were provided with the information about the risks, potential benefits, and alternatives, and to show that they understand it. Signing the document and providing consent is not a contract; participants may withdraw from a study at any time, even if the study is not over.

How long does a clinical trial last?

The length of a clinical trial varies depending on what is being tested and on the protocol. Participants are told how long the trial will last before they enroll.

What is important to know before enrolling in a clinical trial?

It is essential to know as much as possible about the clinical trial before giving consent to take part. You should feel comfortable asking the members of the healthcare team as many questions as you need to about the trial. Below you can find examples of questions that people can find helpful to discuss with the clinical trial healthcare team:

  • What is the purpose of the study?
  • Who is going to be in the study?
  • Why do researchers believe this experimental treatment may be effective?
  • Has this treatment been tested before?
  • What kinds of tests, procedures or treatments are involved in the trial?
  • What will I have to do?
  • What are the possible risks, side effects, and benefits of the study?
  • How might this trial affect my daily life? What effect may it have on my family?
  • How long will the trial last?
  • Where does the trial take place?
  • Will I need to stay in the hospital?
  • How often will I have to visit the hospital or clinic?
  • Who will pay for the experimental treatment?
  • Will I be reimbursed for other expenses such as travel?
  • What type of long-term follow up care is part of this study?
  • How will I know whether the experimental treatment is working?
  • Will the results of the trial be provided to me?
  • Who will be in charge of my care?