Eligibility and what to expect

Understanding clinical trial eligibility

Eligibility criteria can be broken down into:

• inclusion criteria - the features a person needs to have to join a research study
• exclusion criteria - the features that stop someone from taking part

Eligibility criteria can also help keep people safe by considering things that might make the trial too risky for them. For example, you may be excluded from a trial if you are pregnant, have high blood pressure, or have some other condition that increases the risks of the the treatment.

The criteria are unique to each trial, and are often very long and complex. Your doctor is the best person to help you decide whether or not you meet the eligibility criteria for a particular clinical trial.

Other eligibility considerations

Contraception and birth control

People of childbearing age and ability are often requested to utilise effective means of contraceptions. This is because some trials include new or experimental treatments that have unknown or harmful effects that may affect a developing foetus.

Minimum time periods since surgery, radiation therapy, and certain drugs

Past treatments may impact your ability to join particular cancer clinical trials. The inclusion and exclusion criteria will be very specific about which types of surgery, radiation therapy, or drug treatment you may have had and the time that needs to have passed since you had these treatments. Speak with your doctor about whether your treatment history matches the trial's eligibility criteria.

Allergies

Some allergies may exclude you from participating in some clinical trials. This is to ensure the safety of all patients participating in the clinical trial. If you have allergies of some kind, you should speak with your doctor.

Genetic testing

Some clinical trials will require you to undergo genetic testing. You should discuss what this means with your doctor and how this might impact you and your family.

Biospecimens and biopsy availability

Some clinical trials will want to use a sample of your fancer for scientific testing. This is so the researchers can understand your cancer better. They may ask to access a sample that has already been taken through a procedure (e.g. biopsy, blood tests, FNA etc) or request that you undergo a new one.

Ability to read, write and understand English

Some clinical trials may have a requirement that you can read, write and understand English before joining. This can be important to help you understand the study requirements, give informed consent, and safely follow instructions.

However, guidelines for conducting clinical trials in Australia encourage researchers to promote fair access and avoid unnecessary exclusion. This means that if you have limited English, you may be still able to take part if support is available (such as translated documents or professional interpreters) to help you fully understand and participate safely. Ask your treatment team about whether this is available.

What to expect during eligibility checks

Before joining a clinical trial, you will go through eligibility checks to make sure the study is appropriate and safe for you.

This usually involves answering questions about your medical history, having a physical examination, and completing any required tests, such as CT scans and blood tests, to check that the trial is suitable for you. This process is known as screening.

What if I'm not eligible?

It can feel disappointing if you don't meet the criteria for a clinical trial. Not being eligible for one trial does not mean other trials won't be suitable. Each study has its own criteria so you may still be eligible for future trials. 

Importantly, not being eligible for a clinical trial does not mean you are excluded from treatment altogether. There may still be standard treatments or other options that are appropriate for your situation. Your doctor can talk with you about the treatments and supports available to help you make informed decisions about your care.

Who decides on the eligibility criteria for a clinical trial?

In Australia, eligibility criteria for cancer clinical trials are developed by the trial sponsor as part of the study protocol, with input from clinical experts. These criteria are then reviewed and approved by a Human Research Ethics Committee (HREC), which ensures they are ethical, scientifically valid, and consistent with national guidelines before the trial can proceed.