FELINE INTERFERON RESPONSE TO 2-AMINO-5-BROMO-6-METHYL-4-PYRIMIDINOL (U-25, 166)

Abstract

U-25,166, a potential antiviral agent, induced high serum interferon levels in cats at concentrations at least 40 times less than the maximum tolerated dose. Although certain cats responded to U-25,166 by consistently producing higher interferon levels than did other cats, this relationship was not observed if the same animals were injected with Newcastle disease virus or poly I:C. Using a biweekly treatment regimen, cats remained responsive to interferon induction by U-25,166 over an 18 wk period in which 9 of doses of the compound were given. Cats given the compound daily soon became hyporesponsive to interferon induction. Interferon was induced in cats given U-25,166 orally as a suspension or in capsules, but circulating interferon levels were low in cats given the drug by s.c. injection.