COVID-19 antiviral treatment developed in Qld

Australian and US researchers have developed an experimental direct-acting antiviral therapy to treat COVID-19.

The international team from the Menzies Health Institute Queensland (MHIQ) at Griffith University and City of Hope, a research and treatment centre for cancer, diabetes and other life-threatening diseases in the US, used gene-silencing RNA technology called siRNA (small-interfering RNA) to attack the virus’s genome directly, which stops the virus from replicating. Lipid nanoparticles designed at Griffith University and City of Hope were used to deliver the siRNA to the lungs — the critical site of infection.

Funded as an urgent call by the Medical Research Futures Fund, the research, published in Molecular Therapy, was conducted in SARS-CoV-2-infected mice, but suggests that siRNA-nanoparticle formulations can be developed as a therapy to treat COVID-19 patients, as well as used for future coronavirus infections by targeting the virus’s genome directly.

“Treatment with virus-specific siRNA reduces viral load by 99.9%. These stealth nanoparticles can be delivered to a wide range of lung cells and silence viral genes,” said co-lead researcher Professor Nigel McMillan, from MHIQ.

“Treatment with the therapy in SARS-CoV-2-infected mice improved survival and loss of disease. Remarkably, in treated survivors, no virus could be detected in the lungs,” Professor McMillan said.

Professor Kevin Morris, co-lead researcher from both City of Hope and Griffith University, said, “This treatment is designed to work on all betacoronaviruses, such as the original SARS virus (SARS-CoV-1) as well as SARS-CoV-2 and any new variants that may arise in the future, because it targets ultraconserved regions in the virus’s genome.”

Professor McMillan added, “We have also shown that these nanoparticles are stable at 4°C for 12 months and at room temperature for greater than one month, meaning this agent could be used in low-resource settings to treat infected patients.”

“These nanoparticles are scalable and relatively cost-effective to produce in bulk,” Professor Morris said.

Image caption: The Griffith University COVID-19 antiviral research team of Professor Kevin Morris, Dr Adi Idris, Professor Nigel McMillan, Dr Arron Supramanin and Yusif Idres. Image ©Griffith University.