Biologic response (antiviral) to recombinant human interferon alpha 2a as a function of dose and route of administration in healthy volunteers

The kinetics of the antiviral effect of intramuscular and intravenous injections of recombinant human interferon α_2a were investigated in healthy volunteers. Cohorts of eight to 11 subjects received single intramuscular injections of either 0.3 × 10⁶, 3 × 10⁶, or 18 × 10⁶ U or an intravenous infusion of 18 × 10⁶ U over 30 minutes. Serial samples of peripheral blood mononuclear cells were analyzed for antiviral effects including both (2′-5′) oligoadenylate synthetase activity and resistance to vesicular stomatitis virus infection in vitro. A dose-response relationship was established between recombinant human interferon a2, dose and both vesicular stomatitis virus resistance and (2′-5′) oligoadenylate synthetase activity. At the 0.3 x 106U dose an antiviral effect occurred without clinical side effects. The presence of clinical side effects is not necessary for an antiviral effect.