New therapeutic approaches to the alphaherpesvirus infections

The character of diseases caused by alphaherpesviruses has changed over the last decade. The severity of disease and the frequency of acyclovir resistance has increased with the increase in the number of immunocompromised patients. Compounding the trend towards more virulent herpes disease is the current emphasis towards outpatient management of many diseases. Much of the current antiviral research focuses on providing drugs with (i) improved oral bioavailability and pharmacokinetics which permit less frequent oral or topical dosing for suppressive treatment of herpes simplex virus (HSV) infections, (ii) different mechanisms of action for synergic effects in treating resistant HSV infections in the immunocompromised host and (iii) improved efficacy. Future antiviral agents will probably target enzymes or viral factors essential for infection or will inhibit other steps in the viral infection cycle, such as viral entry, protein synthesis or capsid assembly. Medications that augment the immune response constitute another pathway for combating herpes viral infections. Many of the newer experimental agents target essential processes unique to herpesvirus replication and, therefore, potentially have high selectivity.