Clinical trials for cancer treatments aim to find new and better treatments and help to improve outcomes in cancer patients. Cancer clinical trials look at how cancer is diagnosed and treated. They look at the drugs used, how those drugs affect people and how they affect their cancer.

Some clinical trials use new drugs or treatments to treat the cancer.  Some clinical trials look at what happens when existing drugs or treatments are used in new combinations.

Some trials don’t use drugs or treatments at all but focus on the quality of life of someone in cancer treatment or look at the scans and tests used to find more information about their cancer.

Clinical trials look at how cancer is diagnosed and treated. They look at the drugs used, how those drugs affect people and how they affect their cancer.

Some clinical trials use new drugs or treatments to treat the cancer. For example, a trial may look at a new immunotherapy treatment.

Some clinical trials look at what happens when existing drugs or treatments are used in new combinations. For example, giving radiotherapy along with chemotherapy. Or combining chemotherapy with newer drugs like targeted therapies.

Others don’t use drugs or treatments at all but focus on the quality of life of someone in cancer treatment, or the scans and tests used to find more information about their cancer.

Clinical trials can also compare a new treatment to the current, standard treatment. If the early stages of research suggest that the new treatment might be more effective than the standard one, a clinical trial can get evidence about how well the new treatment works.

In Ireland, all medicines must go through a clinical trial before they are given a licence. The standard medical treatments we use for cancer now have all been tested in clinical trials. 

If we did not have clinical trials, we could not develop new and better treatments. Many cancers have been cured and many patients live longer because of treatments tested in clinical trials. If a clinical trial has shown that a treatment works on some people, more trials can then be carried out to see if there are better ways of using it. For example, using different doses or combining a particular treatment with other treatments.

The doctors and nurses who run the trial check throughout the trial that new treatments and their side effects are safe. The consent form you are asked to read and sign if you want to join the trial will explain expected side effects or problems.

Your doctor will also discuss any risks with you. If you decide to take part in the trial, you will receive the best possible care. Your trial doctor and nurse will check you very closely throughout the trial. If the new treatment is not working as well as the standard medical treatment, you will be moved back on to the standard medical treatment.

When a drug is being used in a clinical trial it has already been carefully tested to make sure it is safe to use in a clinical trial, though there may still be serious side effects. Potential side effects will be discussed with you, but are not always predictable. 

All clinical trials are totally confidential. The information collected on the effects of the treatment will be shared with doctors and researchers, but your personal details will be protected. During the trial, you will be identified by a unique patient number. Only the researchers will know your personal details.

There are lots of laws and regulations that say how clinical trials must be carried out. Every clinical trial involving patients in Ireland must be approved by the Health Products Regulatory Authority (HPRA) and a recognised ethical committee. Once the trial has started it will be checked regularly to make sure the regulations are being followed and everything is being done correctly. Every clinical trial is covered by an approved policy of insurance to cover the hospital, its employees, and the patient in case of any injuries as a result of being in the trial.

Speak to your doctor if you have a cancer diagnosis and are interested in taking part in a clinical trial. Your doctor is the best person to give you information about any trials that might be available and suitable for you and your cancer.  It’s not just trials initiated in Ireland that you can participate in - it may also be possible to take part in an international trial.

You may be offered a clinical trial as part of your treatment plan or consultation, if there are any trials that are suitable.  

Your doctor may arrange for you to talk to a research nurse who is part of the team in charge of the clinical trial. The nurse can give you more information about the trial.

Not all trials are suitable for all patients with a particular type of cancer. Trials often need patients who are similar in certain ways. These might include age, gender, cancer type, stage of cancer, whether you have had previous cancer treatment and other medical conditions. For this reason, trials have very strict rules. This means that some people can be included in the trial, while others will not be eligible.  

After your doctor determines your initial suitability for a trial, you may be asked to undergo further screening tests for example, a blood test or scan. This is because new treatments are often targeting very specific subgroups of people and if you are not part of this subgroup, the treatment is unlikely to work. It is only after this screening process that your medical team will know if you are eligible. Unfortunately, it can happen that a person appears to be suitable for a trial initially but on detailed assessment, the person does not meet a key requirement and cannot take part. 

Having strict rules about how patients are picked helps to make the trial safer. It also means the results will be more reliable by making sure that the patients receiving the new treatment are medically suitable and that a fair comparison can be made between similar patients.

You can withdraw from a clinical trial at any time. If the doctor or nurse feels that the trial would benefit you or your cancer long term, they will discuss this with you and make it clear – but the choice is yours.

If you decide you don’t want to be part of the trial any longer, you will be offered the standard treatment instead.

If your doctor has determined your eligibility and you have passed the screening test for the trial, you will be enrolled. The clinical trial team will explain the study in detail and ask you to consent to take part. This consent is yours to give freely and can be withdrawn at any stage without question. 

You may be offered the standard treatment for your cancer or you may also be offered a trial treatment. Remember, you will only be offered a trial treatment if your doctor believes it is at least as good as the standard treatment. You may not know which treatment you are receiving and your doctor may not know either. This is to ensure that the effect of any new treatment is actually down to the intervention and not other factors.

Deciding whether to join a clinical trial can be complex. Usually there are pros and cons to taking part in a trial. If you have any questions about the benefits and any possible disadvantages, talk to your doctor or the clinical trial team.  

If the trial involves a new or additional treatment, you will only be given a choice between the standard treatment and the trial if your doctor believes that both treatments could be equally useful for you. No matter what treatment you have, remember that every patient is different and there is no way of knowing if a treatment is going to work for you before you start it. Your doctors can only give you advice based on what they have learnt from other patients with a disease like yours, so make your decision based on what you feel is best for you.

Here are some questions you might like to ask your doctor:

• What does the trial hope to find out?
• What treatment will I get?
• What is the difference between the trial treatment and standard treatment?
• What are the potential side effects of the trial treatment?
• What are the benefits of taking part?
• What are the risks of taking part?
• How many patients are taking part in this trial?
• What is expected of me during the trial?
• Will any expenses I have for taking part be refunded?
• How long will my treatment take?
• Will I have many extra visits in comparison to the standard treatment?
• Where will I get my treatment? Will I be in the same hospital and have the same doctors?
• When will the trial results be available?
• What will happen if I want to stop the trial treatment?
• What treatment will I have if I do not want to take part in the trial?

Giving consent means that you understand the trial process and agree to take part of your own free will. You cannot be part of a clinical trial if you have not given your consent. If you want to take part, you will be asked to read detailed information sheets and sign a consent form. You will be guided through this process with the clinical trial team and given time to consider your options and ask questions. 

The information sheet explains:

• Why the trial is being run
• What it hopes to achieve
• What the possible side effects and risks are
• Why you have been invited to take part

It is important that you understand everything about the trial before you agree to take part. This is called informed consent. If you want to take part, you will fill in and sign the consent form. This can involve a lot of paperwork, but your doctor and nurse will go through it with you. You can still change your mind at any time, even after you have signed the consent form or started your trial treatment.

Yes. You can withdraw from the clinical trial at any time.

If the doctor or nurse feels that the trial benefits you or your cancer long term, they will discuss this with you and make it clear – but the choice is yours. If you decide you no longer want to be part of the trial, you will be offered the standard treatment instead.

If you leave the trial, you will still get the best possible care.

If you have any concerns about a trial you are taking part in, or you are considering withdrawing, please discuss this with your medical team. 

Each patient starts their treatment at a different time and will be monitored during and after their treatment. Once you have finished your treatment, your doctor will monitor your progress and continue to report back to the researchers. 

As part of the clinical trial, you may be asked to come back for appointments after you have finished your treatment or discuss your health over the phone. It is important that you attend these appointments to help the researchers understand the results of the trial. Sometimes, these check-ins can happen for a number of years after the study and this allows the researchers to determine the long term impact of the trial on participants. 

The results of clinical trials are published in medical journals, but your personal information is not. Your doctor can tell you what the results of the trial are once they have been published. If a trial treatment is shown to have better results than the standard treatment, it will be licensed and become the new standard treatment.

The following terms are used to describe different types of trials. Your doctor or nurse will explain which of these terms is relevant to you. 

• Controlled trials
• Blind and double-blind trials
• Randomised trial
• Placebo

There are 4 main ‘phases’ in the clinical trial process. A new treatment must pass each phase before moving on to the next phase. Each phase is necessary to make sure that the treatment is safe, and is working, and to see how well it’s working. 

Phase I 

Phase 1 is the first stage during which a new treatment is used on people. Before this, the trial is carried out on cancer cells in a test tube or petri dish in a laboratory. Phase 1 trials involve small numbers of people, usually less than 50 and sometimes as few as 10. The purpose of a phase 1 trial is:

• To find a safe dose for the new treatment
• To decide how the new treatment should be given (e.g. tablets/into a vein)
• To see how the new treatment affects the human body

Phase 2

A phase 2 trial also involves a small number of patients, usually less than 100. The purpose of a phase 2 trial is: 

• To find out if the new treatment is particularly useful for certain cancers
• To see how the new treatment affects the body and what are the side effects
• To see if the new treatment is suitable for a phase 3 trial

Phase 3

Phase 3 trials involve much larger numbers of patients, often from many different hospitals and in many different countries. A phase 3 trial might need hundreds or thousands of patients. The purpose of a phase 3 trial is:

• To compare the new treatment with the standard treatment 
• To provide more information on the side effects of the treatment

Phase 4

If a phase 3 trial shows that a new treatment is working, the treatment is licensed, and doctors will begin using it on their patients. Phase 4 trial is the long term monitoring of the safety, effectiveness, and side effects of the treatment.

Clinical trials can take many years to complete. Often, thousands of people will be involved in one cancer trial over several years. The same clinical trial can be taking place all over the world at the same time. This is because the researchers want to be sure that a new treatment or new way of giving a treatment is better than the standard treatment. Even though your treatment as part of the trial is complete, the results of the whole trial might not be known for a long time afterwards. This can be frustrating for patients, doctors, and researchers. However, trials must run for long enough to recruit enough patients and then have the results analysed to make sure that they are reliable.

Sometimes, even though many people are involved in a trial, and it takes years to complete, the improvements in treatment may be small or there may be no improvement at all. However, some trials bring significant changes to cancer treatments and have resulted in significant improvements in survival in recent years. This is why researchers continue to design new trials and patients agree to take part.

Cancer clinical trials are taking place across Ireland within hospitals. Some trials originate from academic researchers and some from pharmaceutical companies. 

In Ireland, Cancer Trials Ireland are the centralised organising body for cancer trials. Disease Specific Sub-Groups (DSSGs) exist within Cancer Trials Ireland to focus on clinical trials within specific target areas, such as breast cancer or haematological cancers. You can find out about trial that are occurring nationally at (opens in a new window)www.cancertrials.ie. However, it's important to note that not all trials are coordinated through Cancer Trials Ireland. 

Additionally, the Health Research Board (HRB) provides millions of euro of funding each year to eight national cancer trial clusters, of which the UCD Cancer Trials Cluster is one. Each cluster is funded co-operatively by the HRB in partnership with the associated university and hospital site. Other clusters include the University College Cork Cancer Trials Group and the Irish Research Radiation Oncology Group

It is generally accepted that participation in cancer clinical trials is low in Ireland. A key goal of the National Cancer Strategy and the UCD Cancer Trials Cluster is to improve enrollment rates into clinical trials. Greater awareness among clinicians is very important in addressing this. It is equally important that patients are aware of the potential of clinical trials and have the confidence to ask about it, particularly around time of diagnosis. We hope that the information provided here will empower patients to ask.