Experimental drug offers hope of inhaler cold cure
A long-awaited cure for the common cold may be in sight after scientists successfully stripped the virus of its armour.
Laboratory tests showed how an experimental drug stopped the rhinovirus hijacking a human protein to build the protective shell, or "capsid".
Without the protein shield, the virus's genetic heart of RNA is exposed and vulnerable - and the virus cannot replicate.
Because all strains of the cold virus use the same mechanism, the research raises the possibility of a universally effective treatment.
In addition, the early tests suggest that the drug causes no harm to host cells.
Scientists hope the new molecule, code-named IMP-1088, can be administered simply using an inhaler.
Lead researcher Professor Ed Tate, from the Department of Chemistry at Imperial College London, said: "The common cold is an inconvenience for most of us, but can cause serious complications in people with conditions like asthma and COPD (chronic obstructive pulmonary disease).
"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."
As well as conquering the common cold, the drug may also work against other related viruses, including those responsible for polio and foot-and-mouth disease, say the scientists.
Most current common cold treatments do no more than alleviate symptoms such as runny nose, sore throat and fever.
The rhinovirus family has more than a hundred variants, providing numerous different targets that have thwarted attempts to develop a common cold vaccine.
The viruses also evolve quickly to become resistant to anti-viral drugs.
But the new approach could be more successful because it does not target the virus directly. Instead it suppresses a human enzyme, N-myristoyltransferase (NMT), that the virus relies on to construct its capsid shell.
The scientists found they were able to block replication of several strains of the virus without human cells being affected.
However, further studies are needed to ensure that the drug is not toxic in the body.
Dr Peter Barlow, from Edinburgh Napier University and the British Society for Immunology, said: "There are currently no drugs or vaccines for rhinovirus that have been licensed for use in humans.
"This is mainly because there are around 160 different types of this virus, so creating a vaccine that is effective against all these types is extremely challenging. The development of new drug treatments for this virus is therefore urgently needed.
"While this study was conducted entirely in vitro, ie using cells to model rhinovirus infection in the laboratory, it shows great promise in terms of eventually developing a drug treatment to combat the effects of this virus in patients."
The findings are reported in the journal Nature Chemistry.