An international team of scientists from the Menzies Health Institute Queensland (MHIQ) at Griffith University and from City of Hope, a research and treatment center for cancer, diabetes and other life-threatening diseases in the U.S., have developed an experimental direct-acting antiviral therapy to treat COVID-19.
Traditional antivirals reduce symptoms and help people recover earlier. Examples include Tamiflu®, zanamivir and remdesivir.
This next-generation antiviral approach used gene-silencing RNA technology called siRNA (small-interfering RNA) to attack the virus’ genome directly, which stops the virus from replicating, as well as lipid nanoparticles designed at Griffith University and City of Hope to deliver the siRNA to the lungs, the critical site of infection.
“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 Nigel McMillan, Ph.D., professor and director of the Infectious Diseases & Immunology Program at 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,’’ McMillan said.
Kevin Morris, Ph.D., professor and associate director of the Center for Gene Therapy at City of Hope and 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 ultra-conserved regions in the virus’ genome.”
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.”
The results suggest 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’ genome directly.
“These nanoparticles are scalable and relatively cost-effective to produce in bulk,” Professor Morris said.
“This work was funded as an urgent call by Medical Research Futures Fund and is the type of RNA medicine that can be manufactured locally in Australia,’’ McMillan said.
The research has been published in Molecular Therapy. A video is available on YouTube.
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About City of Hope
City of Hope is an independent biomedical research and treatment center for cancer, diabetes and other life-threatening diseases. Founded in 1913, City of Hope is a leader in bone marrow transplantation and immunotherapy such as CAR T cell therapy. City of Hope’s translational research and personalized treatment protocols advance care throughout the world. Human synthetic insulin, monoclonal antibodies, and numerous breakthrough cancer drugs are based on technology developed at the institution. Translational Genomics Research Institute (TGen) became a part of City of Hope in 2016. AccessHopeTM, a wholly owned subsidiary, was launched in 2019, dedicated to serving employers and their health care partners by providing access to City of Hope’s exceptional cancer expertise. A National Cancer Institute-designated comprehensive cancer center and a founding member of the National Comprehensive Cancer Network, City of Hope is ranked among the nation’s “Best Hospitals” in cancer by U.S. News & World Report. Its main campus is located near Los Angeles, with additional locations throughout Southern California and in Arizona. For more information about City of Hope, follow us on Facebook, Twitter, YouTube or Instagram.
About Griffith University
Griffith University is a comprehensive research-intensive university ranked in the top 2 percent of universities globally with 50000 students spanning six campuses in South East Queensland, Australia. Its research excellence, innovative teaching and learning practices and strong industry ties makes it one of the leading providers of higher education in the Asia–Pacific.