What is a clinical trial?

Some people with inherited retinal diseases may choose to participate in clinical trials.  For example, in about 2014 three people participated in a proof of concept study for the bionic eye made by Bionic Vision Technologies in Melbourne.  They were given implants to test the safety of the bionic eye and for the purpose of study in the laboratory. In 2018, four people commenced trialling a newer version of that bionic eye.

Clinical trials are medical research studies in which people volunteer to participate. Carefully conducted clinical trials are the safest and fastest way to find treatments that work in people. A clinical trial is used to evaluate the safety and effectiveness of a new procedure, medication or device to prevent, diagnose or treat an eye disease or disorder.

There are four different phases to a clinical trial. The time from a phase one to a phase four trial can take many years.

What are the different phases of a clinical trial?

Phase 1 Trial
These are the earliest trials in the life of a new drug or treatment. They are usually small trials, recruiting up to about 30 patients. Phase one trials are undertaken to determine the safety of a potential treatment. People recruited to phase one trials often have advanced eye disease. This work has to be completed first, as safety is the most important issue to resolve before wider testing of the potential new treatment.

Phase 2 Trial
This type of trial tests the potential new treatment in a larger number of volunteers to learn more about how the body responds to the treatment, the optimal dose of the treatment and how the treatment affects a certain eye condition. If the results of phase two trials show that a new treatment may be as good as existing treatment or better, they move to Phase three. Determining the safety of the drug is a large component of phase two testing and sometimes phase one and phase two trials are run at the same time.

Phase 3 Trial
Treatments only move into a phase three clinical trial if phases one and two suggest that a substance might actually be useful and safe in ways that patients would regard as important. Phase three trials are usually much larger than phase one or two, sometimes involving hundreds or thousands of patients in many different settings. Phase three trials are usually randomised. This means the researchers put the people taking part into two or more groups at random. One group gets the new treatment and the other the standard treatment or a placebo (non-active) treatment.

Phase 4 Trial
Phase four trials are performed after a drug has been shown to work and has been granted a licence. They are performed in order to understand more about the treatment, by evaluating its safety and effectiveness in larger numbers of patients, subgroups of patients, and by comparing it to or combining it with other available treatments. The time from a phase one to a phase four trial can take many years.

 Are there clinical trials ongoing in Australia?

There are a large number of clinical trials that are already at phase one and two stage worldwide for inherited retinal diseases, especially in the area of gene therapy. The aim of these trials is to determine the best dose that is safe to give to an individual. If these trials are successful, they may progress to phase three trials that will test the new therapy on larger numbers of people across many countries, which may include Australia.

To participate in a trial, a candidate must meet a set of ‘entry criteria’. In the case of inherited retinal diseases, candidates may have to have the exact gene that is faulty.

This is why the work of the Australian Inherited Retinal Disease Register & DNA Bank is so important. Please refer to the information below.

How can I find out more information about clinical trials?

The Australian Government, National Health and Medical Research Council provide an excellent source of information about clinical trials on their clinical trials website . Clinical trials that are currently being conducted worldwide can be found on the database maintained by the US National Institutes of Health and can be searched by condition and trial location.

Clinical trials are extremely important. Doctors, other healthcare professionals and patients need evidence from clinical trials to know which treatments work best. Some patients may benefit from participating in a clinical trial. However there are no guarantees that a study participant will receive any direct benefit from participation in a clinical trial.

By volunteering to participate in clinical trials, participants help advance our knowledge about medical interventions. In doing so, clinical trial participants can play an important role in the approval of new drugs and devices for treating other patients.


What happens if I agree to enter a trial but then change my mind?

You are free to leave a trial at any time without having to explain why.

The Australian Inherited Retinal Disease Register and DNA Bank

The Australian Inherited Retinal Disease Register and DNA Bank (AIRDR) was established as a national resource in 2009. It contains clinical and family history information for over 6,800 participants affected with an IRD or their family members. It also contains DNA collected from over 4,900 of those participants. The results of genetic analysis of that DNA (which may include the specific genetic mutation causing a participant’s IRD) are also recorded in this resource, as they become available. As the molecular mechanisms leading to inherited retinal disease become more clearly understood, novel therapies are being developed which will in time prevent or ameliorate loss of sight and improve visual function.

Ultimately, the AIRDR aims to identify the exact genetic profile of the estimated 12,000 people affected by an inherited retinal disease in Australia.  If you have a condition such as retinitis pigmentosa, Choroideremia, Leber congenital amaurosis, Usher syndrome, Stargardt disease, cone/rod dystrophy or others, you can get involved by contacting the AIRDR.

The national register which the AIRDR has established is essential for the progress of genetics research and the enablement of clinical trials. It will also strengthen Australia’s position as a potential location for clinical trials.

The early establishment of an affected person’s genetic status is vital if he or she is to have the opportunity to take full advantage of these emerging therapies. The AIRDR is actively used by clinicians and researchers to identify participants who may be suitable for emerging gene-specific clinical trials, to improve our understanding and treatment of inherited retinal diseases, and to facilitate clinical counselling of patients.

To contact the AIRDR phone: (08) 6457 2866 or Email: The website is: