April 16, 2025

Australia’s first human challenge trials centre opens

Australia’s first clinical trial unit specifically commissioned to conduct human challenge trials, or controlled human infection model (CHIM), Doherty Clinical Trials (DCT) Ltd, was recently opened in Melbourne. 

This type of research involves purposely infecting participants with a pathogen to study the effects of the infection. At the moment, the comfortable 25-bed facility is located in a repurposed building in East Melbourne. In 2027 it will move to a larger site. 

As Professor Sharon Lewin said, “The COVID-19 pandemic highlighted the need to accelerate how new vaccines and treatments are developed. This will help us all to get lifesaving medicines more rapidly in future pandemics. While human challenge trials have been used to develop new medicines and vaccines globally for decades, our purpose-built facility is the first of its kind in the southern Hemisphere, and will build capabilities right here in Victoria enabling rapid research translation.”

Studying human immune response is necessary, as it may improve future vaccines’ effectiveness. In infectious diseases research, human challenge trials have yielded significant results, like Vaxchora, an FDA-approved oral vaccine for cholera. DCT will conduct human challenge trials targeting illnesses like influenza, Streptococcus pyogenes (Strep A), gonorrhoea, and malaria. These studies will be performed in collaboration with other research groups in Australia and elsewhere.

These studies are highly controversial. As in all clinical trials, researchers must recruit volunteers to participate in human challenge studies. Will there be sufficient ethical safeguards for the volunteers? Can infecting volunteers with a virus to develop a vaccine ever be ethical? 

There are critical ethical issues for researchers planning vaccine development research. Questions like whether reasonable care has been provided to maximise the benefits of the study and minimise the risks of harm to the subjects. Is the informed consent process for these participants rigorous enough? 

Only young and healthy participants should be recruited in such an experiment. Rigorous conditions must be observed; only younger populations between 18 and 30 years in excellent health can enrol in the trials. But even younger research subjects can suffer adverse effects or even die. In 1999 18-year-old Jesse Gelsinger, who passed away in a gene therapy trial run by the University of Pennsylvania. After his death, all gene therapy trials in the US stopped for a while. It was a severe setback for gene therapy and a sobering reminder of the risks involved.  

Like all research involving humans, high-quality informed consent is crucial. While taking part in studies is entirely voluntary, it is essential to ensure participant comprehension of the studies and their various risks at the study’s outset. This could be facilitated by requiring the participants to sit for a test on vital study information. 

Moreover, on-going informed consent is critical as new developments may emerge occasionally, such as greater knowledge of the virus and its different transmission methods. Furthermore, long-term monitoring and follow-up of the participants is crucial. After discharge, follow-up appointments must be made.

As enrolling participants in research can be difficult, in some studies volunteers will be paid, sometimes thousands of dollars. Fairness calls for offering participants compensation for their time, inconvenience, discomfort, etc. DCT will pay $23.23 per hour, the minimum wage. Participants are often university students or backpackers, says the CEO of the Melbourne challenge trial centre, Andrew Brockway. 

As Keller Scholl, a 29-year-old student who participated in a US challenge study last year, said: “I want to make the world a better place. This was something I could do, and we don’t have enough volunteers.” But he also said that he “wouldn’t have been able to do it without the pay”, which was about $7,500 for nine days.

What is most concerning is that the money offered to them may induce them to participate in the study, which could compromise genuine informed consent. The compensation should be modest.

While there are arguments against these types of experiments, including the risk of harm to participants, the danger of developing an ineffective vaccine, and the lack of rigour of a volunteer’s informed consent, these concerns are being addressed with strict regulation. Important national guidelines to be observed include the National Statement on Ethical Conduct in Human Research (2023) (the National Statement). This sets down that a Human Research Ethics Committee must approve all research before a study is conducted.

Dr Patrick Foong is a senior law lecturer at Western Sydney University. His research interest lies in bioethics and health law.

Grace Borsellino is a Lecturer in Law at Western Sydney University and the Chair of the School of Law Equity and Diversity Working Party. Her research interests are Corporate Law and Governance focussed exploring the role of corporations in society.

Patrick Foong