Researchers have identified a molecule that can combat the common cold virus by preventing it from hijacking human cells. Early lab-based tests with human cells have shown the molecule’s ability to completely block multiple strains of cold virus, according to the results published in the journal Nature Chemistry. Researchers from the Imperial College London in the UK hope to move to animal and then human trials. The common cold is caused by a family of viruses with hundreds of variants, making it nearly impossible to become immune to or vaccinate against all of them.
The viruses evolve rapidly, meaning they can quickly gain resistance to drugs, researchers said. For these reasons, most cold remedies rely on treating the symptoms of the infection – such as runny nose, sore throat and fever – rather than tackling the virus itself. However, the new molecule targets N-myristoyltransferase (NMT), a protein in human cells.
Viruses ‘hijack’ NMT from human cells to construct the protein ‘shell’, or capsid, which protects the virus genome. All strains of the virus need the same human protein to make new copies of themselves, so the molecule should work against all of them, researchers said. Additionally, the molecule also works against viruses related to the cold virus, such as polio and foot and mouth disease viruses, they said.
The molecule targets a human protein and not the virus itself, making emergence of resistant viruses highly unlikely. “The common cold is an inconvenience for most of us, but can cause serious complications in people with conditions like asthma and COPD,” said Ed Tate, a professor at Imperial. “A drug like this could be extremely beneficial if given early in infection, and we are working on making a version that could be inhaled, so that it gets to the lungs quickly,” Tate said.
“The way the drug works means that we would need to be sure it was being used against the cold virus, and not similar conditions with different causes, to minimise the chance of toxic side effects,” Tate said. The team led by Andy Bell was originally looking for compounds that targeted the protein in malaria parasites.
Screening large libraries of compounds, the researchers found two hits and were surprised to discover that they worked best together. By inventing a novel way to combine the two, they created a molecule, codenamed IMP-1088, which is more than a hundred times more potent than previous molecules targeting the protein in humans.