In vivo antiviral activity of recombinant type alpha interferon A in monkeys with infections due to simian varicella virus.

Recombinant type alpha interferon A (rIFN-alpha-A) administered to African green monkeys (Cercopithecus aethiops) intramuscularly in a dose of 3 X 10(6) units/kg of body weight resulted in substantial blood levels of interferon. Peak levels of greater than 1,000 units/ml of serum appeared at 1 and 2 hr after inoculation and interferon was detectable for as long as 12 hr after inoculation. Injection of rIFN-alpha-A at a dose of 10(6) units/kg twice daily for eight days effectively inhibited simian varicella virus infection of the African green monkey. Antiviral activity was demonstrated in monkeys with prophylactic treatment begun 4 hr prior to virus inoculation or with therapeutic treatment deferred until 44 hr after virus inoculation. No adverse effects of treatment were observed.