FOR IMMEDIATE RELEASE

Landmark Study Shows Suppressive Antiviral Therapy with Valtrex® (valacyclovir HCl) Caplets Reduced Sexual Transmission of Genital Herpes

118 Canadian Couples at Six Centres Participate in Study

TORONTO, Ontario (September 30, 2002) -- Once-daily suppressive therapy with Valtrex® (valacyclovir hydrochloride) caplets reduced transmission of symptomatic genital herpes (genital herpes with active symptoms) by 77 per cent versus the placebo group, according to data presented at the 42nd Interscience Conference on Antimicrobial Agents and Chemotherapy (ICAAC) annual meeting. In addition, suppressive therapy reduced the overall transmission of the virus that causes genital herpes by 50 per cent.

Valtrex is the only product that has been studied for the reduction of the transmission of genital herpes in heterosexual monogamous couples, and is currently indicated by Health Canada for the suppression of genital herpes outbreaks.

"Suppression with valacyclovir 500 mg once daily provides a brand new tool in herpes transmission prevention," said Dr. Stephen Sacks, infectious disease physician and professor of Pharmacology and Therapeutics at the University of British Columbia. "People with genital herpes will want to have an honest herpes discussion with their sexual partner, consider a type-specific blood test for the partner to determine if he or she is susceptible, and use, as we recommended in this study, safer sex as the third principle in prevention. Suppressive therapy adds a novel fourth tool which is very effective." Dr. Sacks went on to caution, "Even with all of these prevention tools in place, it remains possible to transmit genital herpes to a susceptible partner, but valacyclovir suppression significantly reduces the overall risk."

SUPPRESSIVE THERAPY WITH VALTREX® CAPLETS REDUCED TRANSMISSION OF GENITAL HERPES/2

Experts estimate that genital herpes, which can be transmitted by intimate contact during active episodes and is a lifelong infection, affects up to one-in-five adults. There are two varieties of the herpes simplex virus. Herpes simplex virus type 1 (HSV-1) generally establishes infections in the mouth, causing the common cold sore, but can also cause genital herpes when transmitted by saliva to the genital region and by genital-to-genital transmission. Herpes simplex virus type 2 (HSV-2) is the major cause of genital herpes. The virus passes from person to person through sexual contact and although the disease is most contagious during an outbreak, symptoms do not have to be present to infect another individual.

ABOUT THE STUDY

This study compared Valtrex and placebo for the prevention of transmission of genital herpes, HSV-2, in heterosexual monogamous couples where one partner had genital herpes (source partner) and the other did not (susceptible partner).

A total of 1,484 couples (743 valacyclovir, 741 placebo), including 118 Canadian couples in six study sites (Vancouver, Edmonton, Ottawa, Montreal, and two sites in Quebec City), were included in the study population. The source partner was randomized in a 1:1 ratio to receive valacyclovir 500 mg once daily or placebo for eight months. The susceptible partner was monitored monthly for acquisition of HSV-2 during the eight-month study period, and was told to visit the clinic at the first sign of an outbreak. Throughout the study, couples were offered condoms and counselled on safer sexual behaviour at all visits. There were no differences in adverse events between the groups.

SUPPRESSIVE THERAPY WITH VALTREX® CAPLETS REDUCED TRANSMISSION OF GENITAL HERPES/3

ABOUT GENITAL HERPES

More than 86 million people worldwide are infected with the herpes simplex virus that causes genital herpes, and eight out of 10 people who are infected with HSV-2 are not even aware of their condition. The virus never leaves the body, making it a lifelong infection that can recur at various times with or without symptoms. Symptoms of genital herpes may include a cluster of blisters, bumps or rashes in the genital area, or on the thighs or buttocks. To help prevent spreading the disease to others, sexual contact should be avoided during outbreaks and latex condoms should be used at all times.

Health Canada has not yet approved Valtrex for the prevention of transmission.

This study was sponsored by GlaxoSmithKline Inc., a leader in the treatment of herpes infections. GlaxoSmithKline - one of the world's leading research-based pharmaceutical and healthcare companies - is committed to improving the quality of human life by enabling people to do more, feel better and live longer. In Canada, GlaxoSmithKline employs approximately 1,800 people and is a top 25 investor in Canadian research and development, contributing more than $100 million annually. The company is also one of the top 10 corporate charitable donors, investing more than $6.5 million annually and is recognized as one of the 50 best companies to work for in Canada.

NOTE: English and French physicians are available for interviews.

English and French B-roll will run consecutively via satellite on Monday, September 30, 2002.

TIME OF FEED: 14:00 - 14:30 (2:00 - 2:30 p.m.) Eastern

COORDINATES: ANIK E2C, Transponder 6B, Audio Channels 6.8 & 6.2.

For further information about this news release, please contact:

Sherry Zarins/Jessica Matkowsky

Edelman Public Relations Canada

Tel.: (416) 979-1120

Carlo Mastrangelo/Catherine Jackson

GlaxoSmithKline Inc.

Tel.: (905) 819-3000

Valtrex® is a registered trademark, used under license by GlaxoSmithKline Inc.