FAILURE OF INTERFERON FOR PREVENTION OF THE COMMON COLD.

Nasal sprays of recombinant interferon-alpha_2b have been shown to be effective in the prophylaxis of the common cold, but they cause excessive nasal irritation. Sperber and colleagues report on two randomized, double- blind clinical trials using nasal drops of recombinant interferon-beta_serine to prevent colds. In the first study, the 139 patients given interferon and the 157 given placebo had comparable rates of respiratory illness, but the interferon group had briefer illness with milder symptoms.

Encouraged by these results, the investigators undertook a second study one year later, using higher daily doses, but observed none of the beneficial effects seen in the first study: frequency of illness, symptom severity, and recovery of rhinovi…