Clinical trials are an important part of our health system and we answer some frequently asked questions about what happens during a clinical trial.

What Is A Clinical Trial?

Clinical trials are an important part of our health system and are necessary to find out if new treatments are more effective than those currently accepted as the best available standard of care. They are designed to answer a scientific question and compare whether a new treatment is better than the current treatment. In fact, the current treatments that are saving lives today are typically only available because clinical trials have shown that they are beneficial.

All new breast cancer treatments or prevention strategies must be rigorously tested through the clinical trials process before they are made widely available to the community. This includes chemotherapy and hormone treatments to prevent recurrence and save lives, mammograms and breast cancer surgeries.

Who Participates In A Clinical Trial?

People who participate in a clinical trial volunteer to do so. In terms of breast cancer clinical trials, participants have been diagnosed with breast cancer or in regard to prevention trials, are at higher than average risk of being diagnosed with breast cancer.

Participants in any clinical trials need to understand what is going to be involved. This is the process of informed consent, before signing onto a trial. The treating physician and clinical trial coordinator will go through this information with the potential participant. This will include an explanation of the trial protocol and provision of written participant information and consent forms. They will discuss the trials aims, potential side effects and what kind of trial it is. Potential participants are given time to read about it, ask questions, discuss with their friends, family and other health professionals before deciding to enter the trial.

Is It Safe To Participate In A Clinical Trial?


The health and safety of clinical trial participants is the first priority in the trials process. By the time a treatment is used in a clinical trial, it has already gone through exhaustive testing. It will then be used very carefully in a trial with a small number of volunteers to ensure safety, before larger trials are done to find out if it effective against cancer. These trials are designed by doctors and researchers who are highly respected leaders in their field, with the support of rigorous scientific evidence.

As with any medical treatment, there is the possibility of side effects. However, the treatments are developed and tested so that the doses used are not expected to lead to excessive side effects, and that those possible side effects have treatment strategies available. The potential side effects are explained to the person before they choose to enter into the trial, to ensure that they are making an informed decision.

The research is overseen by independent people who are not involved in the initial trial development process. This is done by checking through the clinical trial protocol, which outlines the reason for doing the study, who may participate, the treatments and tests involved, when these will be done and why. This independent panel of scientists, medical professionals and consumers is called an ethics committee. The progress of the clinical trial and the safety of clinical trial participants is carefully reviewed and monitored by an Independent Data and Safety Monitoring Committee and by the ethics committee responsible for approving the clinical trial.

Before joining a clinical trial, potential participants must understand why the clinical trial is being conducted, the potential risks and benefits and what their involvement would include. The decision to participate is made on the basis of information provided to the patient by their treating doctor.

A trial participant can choose to remove themselves from the clinical trial at any time. A patient’s treating doctor can also choose to take the participant off the trial if they believe they are having an adverse reaction to a treatment. If a treatment or intervention being tested in a clinical trial is showing no benefit to participants, then the researchers conducting the study will decide if all participants should be taken off the treatment or intervention being trialled.

What Phases Are Involved During A Clinical Trial?

Clinical trials are generally conducted in four phases. Each phase is designed to answer certain scientific questions.

Phase One Clinical Trial

Phase 1 clinical trials are conducted to test a new biomedical intervention (treatment) for the first time in a small group of people (around 20 to 50 people) to evaluate the safety and side effects of the new treatment or intervention. Phase 1 trials are not usually randomised.

Phase Two Clinical Trial

If the treatment or intervention is proven successful in phase one, it is moved to a phase 2 study and tested in a larger group of people (generally several hundred) to give an indication of how effective it is and to further evaluate its safety.

Phase Three Clinical Trial

Phase 3 clinical trials compare new treatments with the best currently available treatment (standard treatment). Phase 3 clinical trials study the efficacy of a treatment or intervention in large groups of people (several hundred to several thousand). They look at which treatments work best for the disease, how the treatment affects quality of life and learns more about side effects. A phase 3 clinical trial could compare the standard treatment with a new treatment, a different dose of the same treatment or a different way of giving the same treatment. These are usually randomised, meaning that participants are allocated to one of two or more treatment options at random, and neither they or their doctors get to choose which treatment. Determined This helps to remove any biases that could lead to false conclusions being made about the effectiveness of the new treatment. Importantly, with this type of trial, participants are given the current standard of care at a minimum, and the new treatment is hoped to be better than that standard care (or at the minimum, no worse).

Phase Four Clinical Trial

A phase 4 clinical trial is conducted after the new treatment or intervention has been approved and entered routine clinical practice. A phase 4 clinical trial aims to learn more about the side effects and safety of the new treatment, the long-term risks and benefits of the new treatment and how effective the treatment is when used in the general population over a longer period of time.

How Long Do Clinical Trials Take?

The length of a clinical trial is dependent on what kind of trial and treatment is being tested. This means each clinical trial timeline is different and we cannot say definitively how long each phase of a clinical trial will last. If you are considering signing on to a clinical trial, this information will be communicated to you by your treating doctor and the clinical trial coordinator. The following information is intended only as a guide and may not be relevant to your individual situation:

Phase 1 trials may last less than a year as these trials are testing in small groups and evaluate the safety of a new treatment or drug. However, if the patient is benefiting from the treatment, the patient may continue on the clinical trial and treatment for longer. This is dependent on individual circumstances.

Phase 2 trials may be longer than phase 1 trials as there are more participants, which means recruitment may take longer. Though recruitment may take longer, patients may be on the treatment for a similar time to those on a phase one trial.

Phase 3 trials, the most common phase trials, may take longer than phase 1 and 2 clinical trials, but the duration depends on the size of the clinical trial, what stage of cancer is being treated and what the determined end points for the clinical trials. For example, the large adjuvant clinical trials SOFT and TEXT have been going on for around a decade, with follow-up still occurring. This does not mean patients are still receiving active treatment, but it does mean researchers are still examining the benefit of the treatment patients received through follow-up consultations.

Phase 4 trials can last for a few years to more than a decade as it is testing the long-term risks and benefits of a new treatment in a larger population, over a longer period of time.

What Happens When A Clinical Trial Ends?

When a clinical trial has reached its determined end point, the researchers involved in the study will evaluate all the information collected. An analysis is also usually conducted during the clinical trial. All this information collected during and post- trial will help to determine if the treatment or intervention should continue to the next phase of the clinical trial, or if the treatment or intervention should be approved for use in the clinic by the relevant health authorities. Once a new treatment has been proven in a clinical trial, the addition of this treatment to the Pharmaceutical Benefits Scheme (PBS) in Australia and PHARMAC in New Zealand, is a separate process and can take several years.

There are a lot of factors that determine how long it will take for a safe and effective treatment to be approved for use in the clinic. Larger trials that have had thousands of participants will take longer to evaluate than smaller trials. This can take a number of years.

Participants are also usually involved in follow-up for years after their involvement in the active treatment part of a clinical trial. This means they are monitored for many years after their active involvement has finished, including when they have finished taking the treatment tested in the clinical trial. This follow-up could include filling in a survey each year or receiving check-ups with your treating doctor. This helps researchers study the long-term effects and efficiency of the treatment or intervention studied.

If you have participated in a clinical trial, the researchers should make the results of the study available to you directly when they become available. Results are generally presented in reports or published in scientific journals.

Can I Participate In Two Clinical Trials At Once?

Generally, researchers prefer clinical trial participants to be involved in only one clinical trial at a time. This is so they can clearly attribute the risks and benefits of each treatment or intervention to the clinical trial. There are exceptions; however, clinical trial participants can be involved in a therapeutic trial and a tumour banking trial, a quality of life or lifestyle intervention trial simultaneously. Your treating doctor will advise on what trials you can participate in.

Can I Discuss The Clinical Trial With My Family And Friends?


Your doctor and clinical trial team will encourage you to discuss your participation in clinical trials with trusted loved ones so you can feel confident in your choice to participate. Additionally, the more people who are aware of and understand clinical trials the better. This helps to increase participation in clinical trials which helps to further breast cancer research and help to find new and better treatments and prevention strategies for the disease. You may also wish to discuss the trial with other health professionals such as your GP prior to participation.

Will My Details Be Published To The Public?


Patient privacy is of the utmost importance is the clinical trials process. Once you consent to take part in a clinical trial, your information will form part of the clinical trials records and be processed in line with the applicable laws that control clinical trials. This means that identifying information such as name, date of birth and address are removed from your information, and replaced with a code, so that the researchers analysing the information cannot identify you as an individual. In any case, the trial information is generally only meaningful when it is analysed as a group, not from any one participant on their own.

When participating in a Breast Cancer Trials clinical trial, your confidential health information will only be accessed by people involved in the clinical trial, including health care professionals and Breast Cancer Trials research staff who are all dedicated to upholding the rights of trial participants to privacy. Any identifying details are removed by your treating doctor or clinical trial coordinator prior to the data being send to the data repository, for example the Breast Cancer Trials database.

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