The efficacy of intranasal interferonα-2a in respiratory syncytial virus infection in volunteers

In a double-blind, placebo-controlled study, self-administered intranasal interferonα-2a or placebo was given both before and after challenge with respiratory syncytial virus. The incidence of colds and the severity of signs and symptoms were reduced in those receiving interferonα-2a as compared with those given placebo. In a further double-blind, placebo-controlled study, self-administered interferonα-2a or placebo was given only to those volunteers who developed colds following challenge with respiratory syncytial virus. There was no evidence that interferonα-2a reduced the severity of the signs and symptoms or shortened the duration of the illness. The similarity of these results to the effect of interferonα-2a in rhinovirus infections in volunteers is discussed.