To evaluate the effect of an interferon inducer on respiratory tract virus infection, poly l.poly C was administered intranasally to volunteers for a seven-day period beginning one day prior to inoculation of rhinovirus 13 or type A2 influenza virus/Hong Kong/68. In three separate trials, toxic effects were not detected and there was a small, but definite, reduction in symptoms of upper-respiratory tract illness associated with drug treatment. However, there was a variable effect on the pattern of virus infection. In only one of the two rhinovirus studies was a reduction of virus shedding observed. Treatment did not decrease the shedding of type A2 influenza virus. The minimal amounts of nasal interferon stimulated by the intranasally administered poly l.poly C may have been responsible for the less-than-optimal results obtained.
Hill DA, Baron S, Perkins JC, Worthington M, Van Kirk JE, Mills J, Kapikian AZ, Chanock RM. Evaluation of an Interferon Inducer in Viral Respiratory Disease. JAMA. 1972;219(9):1179-1184. doi:10.1001/jama.1972.03190350025006