I want to learn about clinical trials

Clinical trials are a type of research. They involve people and test health-related “interventions” to see how they work (see the next paragraphs for more on interventions). Clinical trials often answer questions like: Is the intervention safe? Does the intervention improve or cure disease, or help people live longer with disease than other treatments? Does the intervention help people feel better?

There are many types of interventions tested in clinical trials. While we often think about clinical trials being done to test drugs, they also test devices, genetic therapies, natural health products, psychotherapies, lifestyle and preventive care interventions, and many other things.

The interventions studied in clinical trials can be very experimental, with little to no evidence about how they might work in people (e.g. new drugs). Or they may already be commonly used by people but more evidence is needed about how they work.

Clinical trials are carefully designed and planned to make sure that risks to the people participating are minimized to the extent possible, and that the questions asked about the intervention(s) can be answered when the trial is finished.

Clinical trials study different treatments or interventions on their own or in combination with others and might include drugs, devices, surgery, radiation therapy, diagnostic procedures, diet and lifestyle.

Clinical trials are done to provide research data, or evidence, about the intervention(s) tested. This evidence helps in deciding what therapies or other interventions might work best for people. Ultimately the goal is to improve medical treatments and peoples’ health and well-being.

The evidence, or results, from clinical trials can be used in many ways. With very new or experimental therapies, clinical trials can provide information about an intervention’s safety and inform decisions about whether to keep testing the intervention. The results of clinical trials are also used by companies as they develop new therapies, by doctors and other health care professionals in their daily practices, and by regulatory agencies (e.g. Health Canada) to decide which drugs and devices are safe and effective for Canadians. Clinical trial results can also help decision-makers decide on how healthcare and healthcare resources or healthcare dollars should be allocated.

Clinical trials are done at many different places. Some examples are hospitals, private companies, doctors’ offices, community clinics and dental offices.

There are some things that you should look for in helping you determine if a clinical trial is a reputable or credible clinical trial:

• If you are asked to pay to participate in a clinical trial. While you may be required to pay for expenses such as travelling to your appointments, parking, etc., you should not be asked to pay to participate in the clinical trial.
• The qualifications of the clinical trial team. Often people on the clinical trial team have worked in or studied the area of the clinical trial or have an affiliation with an academic institution such as a university.
• If the clinical trial application was reviewed by a regulatory agency. Examples of regulatory agencies are Health Canada and the US Food and Drug Administration. Health Canada’s role is to ensure Canadians have access to safe and effective drugs and health products, and they review all clinical trial applications.
• If the clinical trial was reviewed and approved by a research ethics board (also called “REB” for short). The REB reviews proposed clinical trials with an aim to make sure they are acceptable from a Research Ethics Board perspective.
• If the clinical trial was reviewed and approved by the institution or organization (e.g. hospital) where the clinical trial is taking place.

If the clinical trial is being offered in another country, this list of things will still be helpful for you to consider.

In the two videos below, Ms. Sharon Frietag talks about the research ethics process and why it exists. She introduces the research ethics board, including its role and composition.

Clinical trials are designed to answer specific questions about an intervention. They are usually designed by a group of people that can include researchers, doctors, scientists, statisticians, sponsors, and – more and more often – patients and/or caregivers.

There are different types or designs for clinical trials. The design will depend on many things, including what is already known about the intervention(s) and what questions need to be answered.

We provide here a summary of the different types of trials by phase, although there can be differences in design depending on the disease or health condition being studied.

Phase 1: These trials are also sometimes called ‘first in humans’ because it is usually the first time the intervention is tested in people. These trials aim to establish the safety, dose and side effect information of the intervention in a small number of participants (usually 20-80 people).

Phase 2: These trials aim to ensure the intervention does what it is supposed to do and to determine if the dose should be changed, and to continue to learn about potential side effects. This phase is carried out in a larger number of participants (about 100-300 people).

Phase 3: These trials are ‘randomized clinical trials’ and test how long the effects of an intervention last, and continue to learn about potential side effects. There are a large number of participants in this phase (usually 1000s of people). You can read more about randomization below.

Phase 4: These trials are also called post-marketing surveillance because they involve monitoring an intervention after it is being sold (that is, on the market). This phase studies long term effects and any side effects on a very large group of people.

In this video, Ms. Sharon Frietag talks about types of clinical trials and provides information about the different phases of therapeutic trials, their goals and how they work.

A common type of clinical trial is a “randomized” clinical trial. These are typically called “phase 3 trials”. In randomized trials two or more interventions (or treatment arms) are being compared to each other. When a trial is randomized, participants are assigned by chance to one of the interventions (or treatment arms). This helps to ensure the result of the trial is not biased.

There are other types of trials that are not randomized and participants know what intervention or treatment they will get if they participate. These are typically phase 1 or 2 trials and are done with treatments that are still in early testing for safety and effectiveness. Or they may be phase 4 trials that usually happen after a treatment is in widespread use.

Participation in a clinical trial is voluntary.  If you are thinking about participating in a clinical trial it is important that you are provided with enough information to make an informed decision, an opportunity to ask questions and talk to others you may choose to (e.g. your family or friends) and the time to make a decision that is right for you.

A key part of the informed consent processes for most clinical trials is a document called the ‘informed consent form’ or ‘consent form’.   This document should provide all relevant information about the clinical trial and be written in a way that is understandable to you.  You should be given enough time to read it and ask any questions you may have. If you agree to participate, you may be asked to sign the consent form and should be provided with a copy of the form for your own keeping.

Informed consent is an ongoing process throughout a clinical trial. You can withdraw your consent to participate at any time.  If you are in a clinical trial and your doctor or study team learn new information that might affect your willingness to continue to participate (e.g., new safety information about the intervention), you should be provided with this information.

A clinical trial protocol contains detailed documents with information on why the trial is being done, how the trial will be done, how the results will be gathered, analyzed and shared, and who is involved. The typical parts of a protocol include the following information about a clinical trial:

• scientific and medication justification
• key measurements or endpoints of the trial
• who can and can’t be in the clinical trial also called the eligibility and ineligibility criteria
• the assessments that will be undertaken, including what kind, when, and the type of assessment (for example, blood tests, doctors visits, questionnaires, etc.)
• a sample informed consent form
• the number of participants needed and why
• how results will be analyzed and shared
• safety reporting information
• what treatments will be used and how, and how or if any adjustments to treatment will be made
• data that will be collected.