A clinical trial is a research study to answer specific questions about vaccines or new therapies or new ways of using known treatments. Clinical trials (also called medical research and research studies) are used to determine whether new drugs or treatments are both safe and effective. Carefully conducted clinical trials are the fastest and safest way to find treatments that work. Ideas for clinical trials usually come from researchers. Once researchers test new therapies or procedures in the laboratory and get promising results, they begin planning Phase 1 Clinical Trials. New therapies are tested on people ONLY after laboratory and animal studies show promising results.
What is a protocol?
All clinical trials are based on a set of rules called a protocol. A protocol describes what type of people may participate in the trial; the schedule of test, procedures, medications, and dosages; and the length of the study.
What are clinical trial phases?
Clinical trials of experimental drugs usually proceed through four phases:
- In Phase I Clinical Trials, researchers test a new drug or treatment in a small group of people (20 to 80) for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
- In Phase II Clinical Trials, the study drug or treatment is given to a larger group of people (100 to 300) to see if it is effective and to further evaluate its safety.
- In Phase III studies, the study drug or treatment is given to large groups of people (1000 to 3000) to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
- Phase IV studies are done after the drug or treatment has been marketed. These studies continue testing the study drug or treatment to collect information about their effect in various populations and any side effects associated with long term use.
In the case of Enzyme Replacement Therapy (ERT) for Fabry disease, the numbers of involved patients is much less. Due to the nature of rare diseases under Orphan Drug Status, requirements for testing with large numbers of patients is often not possible. Protocols are written to adjust for these smaller patient populations.
What protections are there for people who participate in clinical trials?
The Government has strict guidelines and safeguards to protect people who choose to participate in clinical trials. Every clinical trial in Australia must be approved and monitored by an ethics committee to make sure the risks are as low as possible and are worth any potential benefits. An ethics committee is an independent committee of physicians, statisticians, community advocates, and others that ensures that the clinical trial is ethical and the rights of study participants are protected. All institutions that conduct or support biomedical research involving people must, by Federal Regulation, have an ethics committee that initially approves and periodically reviews the research.
Who can participate in a clinical trial?
All clinical trials have guidelines about who can get into the program. Guidelines are based on factors such as age, type of disease, medical history and current medical condition. Before you join a clinical trial, you must qualify for the study. Some research studies seek volunteers with illnesses or conditions to be studied in the clinical trial, while others need healthy volunteers. Healthy volunteers participate in Phase I trials, vaccine studies, and trials on research on preventive care for children or adults.
The factors that allow you to participate in a clinical trial are called inclusion criteria and the factors that keep you from participating are called exclusion criteria. It is important to note that inclusion and exclusion criteria are not used to reject people personally. Instead, the criteria are used to identify appropriate participants and keep them safe. The criteria help ensure that researchers will be able to answer the questions they plan to study.
With ERT for Fabry disease, affected trial participants were needed in all phases. The type and degree of disease involvement for participation was determined by trial protocols to ensure both the safety of participants and the success of the trial. With a disease such as Fabry, it is often not possible to include all willing participants due to the nature of complications presented by this rare condition.
Who sponsors clinical trials?
Clinical trials are sponsored by government agencies, such as the National Health (NH); pharmaceutical companies; individual physician-investigators; health care institutions such as health maintenance organisations; and organisations that develop medical devices or equipment. Trials can take place in a variety of locations such as hospitals, universities, doctor's offices, or community clinics. In the case of Enzyme Replacement Therapy for Fabry disease, the clinical trials have been sponsored by two separate pharmaceutical companies: Genzyme Corporation and Transkaryotic Therapies Inc. (later purchased by Shire).
What happens during a clinical trial?
The clinical trial process depends on the kind of trial you participate in. The team will include doctors and nurses as well as social workers and other healthcare professionals. They will check your health at the beginning of the trial, give you specific instructions for participating in the trial, monitor you carefully during the trial, and stay in touch with you after the study. Some clinical trials involve more tests and doctor visits than you would normally have for your illness or condition.
For all types of trials, you will work with a research team. Your participation will be most successful if you follow the protocol carefully and stay in contact with the research staff. Some terms that will help you understand what happens in a trial are defined below.
What is a placebo?
A placebo is an inactive pill, liquid or powder that has no treatment value. In clinical trials, experimental treatments are often compared with placebos to assess the treatment effectiveness. In some studies, the participants in the control group will receive a placebo instead of an active drug or treatment.
What is a control or control group?
A control is the standard by which experimental observations are evaluated. In many clinical trials, one group of patients will be given an experimental drug or treatment, while the control group is given either a standard treatment for the illness or a placebo.
What is a double-blind or double-masked study?
A double-blind or double-masked study is one in which neither the participants nor the study staff know which participants are receiving experimental treatment and which ones are getting either a standard treatment or a placebo. These studies are performed so neither the patients' nor the doctors' expectations about the experimental drug can influence the outcome.
What is an open-label trial?
An open-label trial is a study in which both researchers and participants know what drug a person is taking and at what dose.
What are side effects and adverse reactions?
Side effects are any undesired actions or effects of drug or treatment. Negative or adverse effects may include headache, nausea, hair loss, skin irritation, or other physical problems. Experimental treatments must be evaluated by both immediate and long-term side effects.
What are the benefits and risks associated with clinical trials?
There are both benefits and risks associated with clinical trials. By participating in a clinical trial, you can;
- Take an active role in your own healthcare
- Gain access to new treatments that are not available to the public
- Obtain expert medical care at leading healthcare facilities during the trial.
- Help others by contributing to medical research.
Clinical trials have risks;
- There may be side effects or adverse reactions to medications or treatments.
- The treatment may not be effective for you
- The protocol may require a lot of your time for trips to the study site, treatments, hospital stays, or complex dosage requirements.
What should I know before I join a clinical trial?
You should know as much as possible about the research study. It is important for you to feel very comfortable asking questions and the staff should answer them in a way that you can understand. Everything should be fully explained to you, but it is a good idea to write questions down before speaking to a study co-ordinator or physician because it is easy to forget when you actually meet.