Oral Acyclovir

Acyclovir is one of the most common treatments for the treatment of genital herpes. Genital herpes is an infection caused by the herpes simplex virus or HSV. HSV is a lifelong infection that is incurable. Many patients suffer from recurrent outbreaks provoked by various environmental and patient-specific factors.

Emisphere's Eligen^® Technology has been used to improve the absorption and bioavailability in humans of small molecules. As a result of these successes, Emisphere has initiated a program to develop an improved oral formulation of the antiviral compound, acyclovir, while using less of the drug.

Acyclovir alone is poorly and irreproducibility absorbed when dosed orally. The published bioavailability is between 10 and 20%. Emisphere has generated preclinical data which show that the Eligen^® Technology can increase the bioavailability of Acyclovir by a factor of five.

Emisphere has entered into a research collaboration for Acyclovir with a pharmaceutical Company based outside the United States. This Company funded several Phase I clinical studies during 2006 and 2007 and continues to support product development of an improved oral Acyclovir using Emisphere's Eligen^® Technology. An Acyclovir study will generate data that Emisphere and its partner will review prior to drawing conclusions.