Abstract: The invention relates to agents for the treatment, therapy and inhibition of Flaviviridae virus infections, which agents comprise proteasome inhibitors as the active component. The agents which are used for inhibiting the release, maturation and replication of Flaviviridae comprise, as the active component in pharmaceutical preparations, substance classes which share the common property of inhibiting the 26S proteasome in cells. These substance classes include, in particular, proteasome inhibitors which affect the activities of the ubiquitin/proteasome pathway, in particular the enzymic activities of the 26S and the 20S proteasome complex. The application of the invention lies in the antiviral therapy of Flaviviridae infections, especially in preventing the establishment and maintenance of a chronic hepatitis C virus infection and a hepatopathogenesis which is associated therewith.