A neuroscientist and biochemist's antiviral lightbulb moment

While studying how certain processes work inside the human brain, an Australian scientist observed a disruption in a pathway viruses rely on to spread cell to cell.

Dr Merja Joensuu, a University of Queensland (UQ) neuroscientist and biochemist, believes a new treatment for deadly infectious diseases including COVID‑19, pneumonia in infants and children, or viral infections caused by Ebola and hantavirus, could be made possible thanks to an unexpected observation made while working on unrelated research.

“We were studying how certain processes work inside the human brain when I noticed a disruption in a pathway that numerous human viruses rely on to spread from one cell to the next,” said Joensuu from UQ’s Australian Institute for Bioengineering and Nanotechnology. “That was the lightbulb moment,” Joensuu added. “We realised that if we interfere with that pathway, we might be able to stop viruses from forming properly.”

Along with collaborator Professor Giuseppe Balistreri from the University of Helsinki, the research team searched for a compound that could inhibit this pathway and found one currently being trialled as a cancer treatment. The compound’s target was human enzyme N‑myristoyltransferase 1 (NMT1), which helps direct where proteins are located and how they function within human cells.

“Viruses can’t reproduce on their own, so they hijack human cells to make new copies,” Balistreri said. “This drug disrupts how the cell functions, causing new viruses to be assembled incorrectly.” Balistreri added: “The virus doesn’t know this and keeps making and releasing less effective versions of itself, which would give the immune system time to clean up the infection.”

By testing the drug in laboratory studies against a range of viruses in cell cultures — including SARS‑CoV‑2 (which causes COVID‑19), respiratory syncytial virus, a major cause of pneumonia in infants, and vesicular stomatitis virus, which causes disease in cattle, horses and occasionally humans — it was found that infection levels dropped by about half after one day, and by up to 90% after two days.

“The reduction is quite striking,” Joensuu said. “The study also suggests this strategy could potentially work on viruses with high mortality rates and long incubation time like Ebola and hantavirus.

“All viruses rely on exploiting host cell processes to replicate and spread,” Joensuu added. “Because we are interfering with the host cell instead of directly targeting the virus, there is less chance of it mutating and building resistance to the drug.”

Joensuu said it showed a lot of promise. “You can imagine that this could be a very effective antiviral, for example with treating respiratory conditions, used in the form of a nasal spray or an inhaler.” The drug is not approved for use and further studies are needed to confirm safety and effectiveness, the researchers emphasised.

The study was published open access in Nature Communications and you can read it at doi.org/10.1038/s41467-026-72938-z.

Image: Dr Merja Joensuu (R) and a colleague look at cells through a microscope. Credit: The University of Queensland