Experimental Spray Cuts Cold Symptoms, Study Says
Researchers for the first time have reduced the severity of the common cold using a nasal spray to block the entry of cold viruses into the body, a finding that could change the way colds are commonly treated.
Eventually, should the drug be approved, a person confronted by a sick child, an infected roommate or a sneezing lover could simply squeeze the experimental nasal spray into his or her nose. It wouldn’t stop that person from catching a cold, but it would cut symptoms by half without the annoying side effects of antihistamines and other cold remedies, researchers told a meeting of the American Society of Microbiology on Tuesday.
The nasal spray has been tested in only 177 people so far, however, and it will be several years before it would be available at the corner drugstore, Dr. Ronald B. Turner of the Medical University of South Carolina said. “I don’t know if I am willing to say that we have a cure for the common cold,” he told the Toronto meeting, “but this technology looks promising. It reduces symptoms dramatically.”
If the drug works as well as he predicts, it could have a major impact on society. Normal people contract 100 colds during their lifetimes. Young children can catch as many as 12 a year. According to the National Health Survey, colds cause 79.5 of every 100 U.S. males and 94.5 of every 100 females to miss at least two days of work or school each year.
Vaccines don’t work for colds because the sneezing, sniffling disorder is caused by as many as 200 different viruses. Blocking all, or even most, of them with one vaccine is simply impossible.
But in the mid-1980s, researchers discovered that as many as half of those viruses enter the body by binding to a single receptor in the nose. In 1989, two different groups, one sponsored by Boehringer Ingleheim Pharmaceuticals and one by Bayer Corp., reported that they had identified and cloned that receptor, a protein molecule called ICAM-1.
The race was on to develop a drug that would bind to ICAM-1 and prevent the virus from attaching to it and entering the body. The first heat of that race was apparently won by Boehringer, which developed the compound that Turner studied.
Turner and Dr. Michael Scheid of the University of Virginia tested the new compound, called BIRR 4, in 177 people. Part of the group was given the drug seven hours before they were exposed to a cold virus, part of it was given the drug 12 hours after the exposure, and the rest received a placebo.
Those receiving the drug either before or after exposure had about 50% fewer symptoms--such as stuffiness, headache, cough, runny noses and sore throats--than those receiving dummy sprays. By comparison, over-the-counter cold remedies reduce symptoms by about a third, and they do so by reducing the body’s own immune response to the virus rather than blocking its entry.
And while antihistamines in such remedies can make the user sleepy or cause other side effects, Turner said BIRR 4 produced few such effects.
Scheid cautioned, however, that it is too early to tell if the treatment would be cost-effective. The company also must test the drug for long-term safety as well as effectiveness.
Scheid said that if the drug works it would probably be most useful in the fall and late spring, when colds caused by rhinoviruses--the group that targets ICAM-1--are most common.
