Studies on the Antiviral Effect of Rifampicin in Volunteers

Abstract

RIFAMPICIN¹ is a clinically useful, orally active antibiotic², synthesized from rifamycin SV(ref. 3), a product of Streptomyces mediterraneans. This antibiotic is effective in the treatment of a number of bacterial infections, especially in tuberculosis^2,4; it has also been shown to inhibit the replication of poxviruses in tissue cultures^5–9. Further studies have indicated that the antiviral effect of rifampicin is selective in that it does not affect uptake into cells of some precursors, and also in that viruses other than poxviruses can replicate in the presence of the drug^5,10. The mechanism by which the selective antiviral effect is mediated seems to involve an inhibition of late viral protein synthesis¹¹, virion assembly¹² and possibly also the de novo synthesized viral polymerase¹³. More recent experiments (to be published) have shown that rifampicin inhibits the formation of lesions resulting from infection with vaccinia virus on the chorioallantoic membrane of embryonated eggs, and on the skin of rabbits, when the drug is locally applied.