Resistance of Herpesviruses to Antiviral Agents

Abstract

Acyclovir is the prototype of a series of antivirals which are effective against herpesviruses. However, resistance to this class of drugs can occur and is being seen mainly in immunocompromised patients with herpes simplex virus (HSV) and varicella-zoster virus (VZV) infections. Clinical use of intravenous ganciclovir began in 1984 for the treatment of life-threatening and sight-threatening human cytomegalovirus (HCMV) infections in immunocompromised patients. A few years later, emergence of ganciclovir-resistant HCMV strains was reported in AIDS patients with HCMV retinitis and, thereafter, in organ or bone marrow transplant recipients. Foscarnet and cidofovir became available subsequently, and resistance to these agents has also been described.