From the sniffling and sneezing to the stuffiness and overall ickiness, the common cold is often just annoying. But researchers have been trying to find a cure for centuries simply because this irritating malady is so prevalent.
What makes a cure so elusive is that the most common cause of a cold — rhinovirus — comes in many forms and can evolve quickly. That makes it nearly impossible to develop an immunity or to create a vaccine to protect against all strains.
Now, a team of scientists from Imperial College London believe they've made progress. They've developed a molecule that will block several strains of rhinovirus. The molecule targets a protein in cells called N-myristoyltransferase (NMT), that viruses "hijack" to form a protective shell, which allows them to multiply.
Every strain of the common cold needs the same protein to replicate, so this molecule could have the ability to fight all of them, the researchers say. The molecule targets a human protein and not the virus itself, making it highly unlikely that the viruses would become resistant.
"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," lead researcher Ed Tate, professor of chemical biology at Imperial College London, said in a statement.
Tate emphasized that although a cold can be an annoyance for many people, it can be quite serious for people with asthma and chronic obstructive pulmonary disease (COPD). The molecule also works against viruses related to the cold virus, such as polio and foot and mouth disease viruses.
"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 minimize the chance of toxic side effects," Tate said.
The scientists' work was published in the journal Nature Chemistry.
A long way to go
Although researchers say their work is promising, they believe a cure is still a long way off. So far, the only human tests have involved cells in a dish.
"We haven’t done any animal studies, and we obviously haven’t done any studies in humans, so I can't tell you formally what the animal toxicity of this compound is," study co-author Roberto Solari, visiting professor at the National Heart and Lung Institute, Imperial College London, told The Guardian.
Although the molecule appears to prevent the virus from replicating, the tests were completed one hour before, one hour after, or at the same time the cells were infected. And they stayed effective for as long as three hours after infection.
Solari said researchers are unclear whether this approach will work by the time cold symptoms appear, which is typically a few days (not hours) after a person has been infected.
"There is a still a long way before this becomes a medicine," he said.