Researchers at City of Hope, a research center based in California, and Griffith University in Australia have collaborated to create a new experimental anti-viral therapy that can treat COVID-19. The therapeutic consists of small interfering RNA (siRNA) molecules encapsulated within lipid nanoparticles. When delivered into the bloodstream, the nanoparticles travel to the lungs. There, the siRNA is released into infected cells and proceeds to bind to and disrupt the genome of the SARS‑CoV‑2 virus.
The COVID-19 pandemic has evolved over the past year, and with the ongoing vaccination campaigns, many people now have a measure of protection against the virus. However, it will still be some time before enough people are vaccinated globally to achieve anything approaching herd immunity. New viral variants are also giving governments around the world sleepless nights, as there is always a risk that the virus will evolve to avoid the protective immunity granted by our current vaccines.
In any case, it looks like we are in this fight for quite a while to come, so new technologies that help us to treat infected patients are very welcome. This latest nanotechnology fits the bill, and is highly specific for the SARS‑CoV‑2 virus. The gene-silencing technology consists of siRNA that is loaded into lipid nanoparticles, intended to shield the siRNA in the bloodstream and deliver it to the lungs where it can enter infected cells.
The siRNA then binds to genetic material from the virus, ultimately resulting in its destruction and breaking the cycle of viral replication. So far, the nanoparticles have been tested in mice. “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 Nigel McMillan, a researcher involved in the study, in a press release. “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.”
Excitingly, the technology may be useful against new variants of the virus, and it is also suitable for long-term storage, a key attribute for widespread use and adoption. “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,” said Kevin Morris, another researcher involved in the study. “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,” added McMillan.
See a video about the technology below.
Study in Molecular Therapy: A SARS-CoV-2 targeted siRNA-nanoparticle therapy for COVID-19
Via: City of Hope