The present invention relates to field of intravaginally applicable devices that release antiviral compounds. In particular, the present invention relates to vaginal rings comprising a matrix releasing at least one antivirally active compound, in particular anti-herpetic compound N-[5-(aminosulfonyl)-4-methyl-1,3-thiazol-2-yl]-N-methyl-2-[4-(2-pyridinyl)-phenyl]-acetamide (in the following also referred to as “Pritelivir”) or salts thereof. The present invention therefore relates to the treatment and prevention of herpes infections.