Clinical trials are an essential part of the development of new interventions and tests that may improve your health care, alleviate the symptoms of your disease or condition or improve the health care of others.
Clinical trials are research investigations in which people volunteer to test new treatments, interventions or tests as a means to prevent, detect, treat or manage various diseases or medical conditions. Some investigations look at how people respond to a new intervention* and what side effects might occur. This helps to determine if a new intervention works, if it is safe, and if it is better than the interventions that are already available.
Clinical trials might also compare existing interventions, test new ways to use or combine existing interventions or observe how people respond to other factors that might affect their health (such as dietary changes).
The World Health Organization (WHO) definition for a clinical trial is
‘any research study that prospectively assigns human participants or groups of humans to one or more health-related interventions to evaluate the effects on health outcomes’.
Clinical trial interventions include but are not restricted to:
- experimental drugs
- cells and other biological products
- medical devices
- surgical and other medical treatments and procedures
- psychotherapeutic and behavioural therapies
- health service changes
- preventive care strategies and
- educational interventions.
Researchers may also conduct clinical trials to evaluate diagnostic or screening tests and new ways to detect and treat disease.
*The word ‘intervention’ will be used to refer to interventions, treatments and tests throughout this website.
How clinical trials work
Researchers may first test new interventions in the laboratory and in animal studies. The most promising experimental interventions are then moved into clinical trials where they are tested in humans. During a clinical trial, more information is gathered about the effectiveness and safety of a new intervention.
In a clinical trial, the new intervention will usually be compared against something else, called a control. The control can be either a placebo (a substance containing no medication) or an established intervention that is already in use.
In Australia, clinical trials are governed by national ethics guidelines and codes of conduct. For further information on requirements, see the National Statement on Ethical Conduct in Human Research (link is external) and the Australian Code for Responsible Conduct of Research.
Clinical trials of unapproved substances and devices also must comply with the requirements of the Therapeutic Goods Administration (link is external) (TGA) and with international guidelines, as adopted by the TGA.
Ethical guidelines and giving consent for a trial:
Clinical trials in Australia are regulated by laws and codes of conduct that aim to protect trial participants and the integrity of the research. All clinical research projects in Australia must be approved by a Human Research Ethics Committee (HREC) (link is external), which checks that the research conforms to the requirements of the National Statement on Ethical Conduct in Human Research.
Anyone taking part in a trial must be fully informed about the objectives of the research, what is expected of them and any risks and potential inconveniences that may be experienced during and after the trial. If you are thinking of being part of a trial, you should be given a participant information and consent form that contains details of the trial and your participation as part of the process of informed consent.
Trials must follow a carefully controlled protocol, which is a plan that describes what researchers will do in the study. As a clinical trial progresses, researchers may report the results of the trial at scientific meetings, to medical journals and to various government agencies. When they do this, the names and personal details of trial participants are kept confidential and are not disclosed.
Who conducts clinical trials?
Researchers conducting clinical trials can be part of hospitals and other medical institutions, specialised research groups, universities, or pharmaceutical, medical device and biotechnology companies, or a combination of these.
A clinical trial team includes doctors and nurses and may also involve other health care professionals, social workers, biostatisticians and trial coordinators and monitors. At the beginning of the trial, the clinical team take initial measurements and a medical history from the participant and give them clear information about what to expect in the trial and what they need to do. During the trial, each participant is monitored carefully by members of the trial team
Who funds clinical trials?
Clinical trials are sponsored or funded by various organisations or individuals, including government departments and agencies, research groups, foundations, charities, and pharmaceutical, medical device and biotechnology companies.
Who can be part of a clinical trial?
Due to the wide variety of trials taking place, almost anyone can take part in a clinical trial. Trials can involve people of all ages, from children to the elderly, and with all types and stages of a disease or condition. Taking part in a trial is completely voluntary and participants can withdraw at any time with no adverse effects on the quality of their medical treatment or relationship with their doctor.
Some trials need healthy participants to test the safety of new interventions or tests, particularly in early stage trials. In these trials, healthy participants can be compared with patient participants. They receive the same test, procedure or drug that the patient group receives and researchers can compare the effects and side effects of the new test, procedure or drug between the two groups.
Many trials need participants who have the disease or condition that the new intervention targets. Patient participants test the new intervention to see what effect it has on their disease or condition.