NEW YORK, May 18 (Reuters Health) -- Tremacamra, an experimental treatment sprayed into the nose, reduces symptoms of the common cold, such as nasal congestion, cough, sneezing, sore throat and headache, US researchers report.
Tremacamra works by binding to the same sites that rhinoviruses use on cell surfaces, preventing the viruses from spreading.
When sprayed into the nose six times a day, tremacamra greatly improved the symptoms caused by one rhinovirus, according to a report in the May 19th issue of The Journal of the American Medical Association.
Dr. Ronald B. Turner and colleagues from the Medical University of South Carolina in Charleston, and the University of Virginia in Charlottesville, gave tremacamra or a placebo (inactive drug) to 90 healthy volunteers, starting 7 hours after exposing them to a rhinovirus commonly used in cold studies. They gave another 106 volunteers tremacamra or placebo beginning 12 hours after rhinovirus exposure.
Rhinovirus infections occurred in most volunteers, whether or not they received tremacamra.
Even though they got infected, volunteers who received tremacamra suffered only about half the total symptoms and three-quarters of the clinically obvious colds experienced by the group that received a placebo.
In an interview with Reuters Health, Turner compared tremacamra's benefits to those of existing treatments. "The magnitude of its effect on symptoms is somewhat better than what's out there," he said. "For example, antihistamines in this model give only about a 25% improvement in runny nose symptoms. Tremacamra gave about twice that."
An editorial by Dr. Kenneth McIntosh of Children's Hospital in Boston, Massachusetts, cautioned against mistaking these early results as evidence of a cure.
"Previous antiviral drugs have faltered when used for treatment," he wrote, "and it remains to be seen whether tremacamra will have effects when given after symptoms have started, particularly in naturally occurring colds."
Turner echoed McIntosh's caution, but offered hope. "It's hard to give a take-home message the first time you put something into humans. While these results are interesting, we're very early in the game. But the good news is," he added, "we're making progress."
SOURCE: The Journal of the American Medical Association 1999;281:1797-1804, 1844-1845.
