Clinical trials are a type of research studies that may be testing a new treatment approach or new drugs. In oncology, they are the best way to develop new treatments to treat cancer, and often are comparing a new approach to current standard treatments or testing a new treatment when there is no current beneficial treatment. They also provide the opportunity to access the newest treatment for cancer, often long before it becomes widely available, but possibly before it’s benefit has been proven.
The suitability of a clinical trial for each patient depends on the cancer type and stage, prior treatments given, their other health problems, the overall potential for risks and side effects compared to potential benefits, and patient preferences. If you want to know more about clinical trials in your particular circumstances, talk to you doctor or health professional.
Clinical trials must be approved by a regulatory authority in the country in which they are being conducted. In Australia, that overarching authority that guides the ethical review and approval of clinical trials is the National Health and Medical Research Council. All clinical trials in Australia must conform with international Good Clinical Practice Guidelines and ethical principles enshrined in the Declaration of Helsinki.
Each trial has its own clinical trial team led by a doctor and including other medical professionals, such as nurses, pharmacists and other specialists. Clinical trials may be conducted in at only one site, at a small number of sites, or across many sites nationally and internationally.
Clinical trial phases
Broadly, there are four types or ‘levels’ of clinical trials:
Phase I clinical trials is all about checking the safety of a proposed treatment, ways in which it can be administered and appropriate dosage levels. It generally involves a relatively small number of participants, and close monitoring of the participants is required. These are often referred to as ‘first-in-human’ studies.
Phase II trials generally aim is to confirm/check the safety and effectiveness of the new treatment, and generally involves a small number of participants who are closely supervised by specialists in that condition.
Phase II trials typically involve a much larger group of participants than phase I or II. The aim is to determine whether there is a 'clinical benefit' to the new treatment over and above current treatments. Side effects or potential side effects continue to be investigated during this phase.
In phases III trials (and sometimes in phase II studies), not all participants will necessarily receive the proposed new medicine. A 'control' or 'reference' will be given either the normal treatment or a placebo (dummy medicine with no active ingredient) while other participants will receive the new treatment. This is referred to as a placebo-controlled trial' where it is common that neither the participants nor the specialists and researchers know who is receiving the treatment and who is receiving the placebo. This ensures a meaningful result.
During any experimental treatment approach, and when there is a serious or unexpected side effect for any participant, or where the treatment is clearly not effective, a participant on a trial will be discontinued so that any necessary medical attention can be provided, and alternative treatment options are considered.
Phase IV studies, often referred to as ‘post-marketing’ studies, involve checking whether the proposed treatment is effective in the 'ordinary clinical setting' of the condition, as opposed to the more restricted settings of phase I-III studies.
Participation advantages and disadvantages
The benefits of participating in a clinical trial include:
- Early access to new treatments.
- New treatment is provided at no cost during the trial.
- Extensive medical care during the trial.
- Helping in the process of identifying potentially life-saving medicines.
There are also some disadvantages:
- Possible side effects which can sometimes be unexpected.
- The treatment may not be effective.
- You may receive the placebo, not the new treatment.
- You may need to spend more time in the hospital or the doctor's surgery.
Visit the NHMRC website for a list of current clinical trials in Australia.