New antiviral drugs that target herpesvirus helicase primase enzymes.

Herpesviruses have infected the majority of the world's population and the associated diseases have plagued humanity since ancient times. Nine causative human herpesviruses have been identified so far. The first antiviral drug was launched in 1962, and since then several drugs for treating herpesvirus infections, which work via different mechanisms, have been developed. Current treatments abrogate or suppress disease symptoms but are not curative. A vaccine based on the OKA strain of varicella zoster virus is being marketed, but to date no therapeutic or prophylactic herpes vaccinations that can treat or stop spread of other herpes diseases are available. Herpes simplex virus causes mucocutaneous infections such as herpes genitalis (genital herpes) and herpes labialis (cold sores), the potentially sight-impairing herpetic eye disease, and life-threatening herpes encephalitis or disseminated disease. Recently, reports of helicase primase inhibitors, the first non-nucleosidic antiviral compounds, which are superior in pre-clinical profile to current herpes simplex virus medication, have been published. This review summarizes the data on helicase primase inhibitors and compares their pre-clinical profile with the established medical standard.