COVID SHIELD is a major collaborative effort led by the Walter and Eliza Hall Institute of Medical Research in partnership with human data science company IQVIA.
The trial is being run through hospitals across the country, including in Victoria, New South Wales, South Australia and the Australian Capital Territory.
The trial's lead investigators are the Institute's joint head of Infectious Diseases and Immune Defence Professor Marc Pellegrini, and Professor Ian Wicks who is joint head of Clinical Translation at the Institute and a rheumatologist at the Royal Melbourne Hospital.
COVID-19 is caused by the newly identified virus SARS-CoV-2. The virus can lead to a severe and progressive respiratory illness, requiring ventilatory support and it can be fatal.
Professor Pellegrini said that in addition to searching for vaccines and treatments, it was important to explore preventative medicines to combat the COVID-19 pandemic.
"COVID SHIELD is gold standard in its design as a multi-centre, randomised, double-blind study," he said.
"The trial is focused on our frontline and allied healthcare workers who are at an increased risk of infection due to repeated exposure caring for sick patients. Our aim is to help people stay safe, well and able to continue in their vital roles."
The trial will enrol 2250 participants through participating hospitals and healthcare providers. Half of the participants will be given hydroxychloroquine, while the other half will receive a placebo tablet - both for the duration of four months.
Professor Wicks said hydroxychloroquine was a well-known prescription medication that had been used for more than 50 years, initially for malaria and subsequently for autoimmune diseases, such as lupus and rheumatoid arthritis.
"Rheumatologists are very comfortable with the drug's safety profile. Like any medication hydroxychloroquine has certain side effects, but fortunately these are well known and quite uncommon.
"The medical specialists conducting COVID SHIELD are highly experienced in using hydroxychloroquine in the clinic. All participants will be screened based on rigorous selection criteria and closely monitored throughout the trial to ensure safety," he said.
Professor Wicks said there were other trials underway assessing the drug's activity as a treatment, but that COVID SHIELD was the first to test the drug as a prophylaxis (prevention) against contracting COVID-19.
"We are hopeful this Australian trial will provide a definitive answer to this question. Hydroxychloroquine has shown promising anti-viral activities, including against SARS-CoV-2, and so this is what we will be exploring further," he said.
Professor Pellegrini said the hydroxychloroquine to be used in the study had been supplied by the manufacturer for that purpose and therefore would not impact patients who routinely required the drug for other conditions.
"COVID SHIELD will not be diverting hydroxychloroquine for routine use from pharmacies, hospitals, or other patient supply chains," he said.
Frontline and allied healthcare workers who wish to participate in the trial can visit https://www.covidshieldtrial.com.au/ from 20 May 2020 to see if they are eligible for the study.
The research is supported by the Australian Government.
About the Institute's COVID-19 response
The Walter and Eliza Hall Institute is leading a number of major research responses to COVID-19 in collaboration with research partners in universities, hospitals and the private sector.
Our researchers are working towards better approaches to diagnose, treat and prevent the spread of coronaviruses, both to address the current COVID-19 global outbreak, as well as in preparedness for future coronaviral disease outbreaks.