Roche Seeks to Broaden Tamiflu Treatment Indication with Pediatric Application

Tamiflu™ (oseltamivir phosphate), the number one prescribed antiviral treatment for influenza, shown to treat children 1 year and older

Nutley, NJ -- June 16, 2000

Hoffmann-La Roche Inc. and Gilead Sciences, Inc. (Nasdaq: GILD) today announced that Roche has submitted an application to the U.S. Food and Drug Administration (FDA) for a new indication for its influenza antiviral Tamiflu™ (oseltamivir phosphate) for the treatment of acute illness due to influenza in children 1 year and older. Tamiflu, the first pill to treat most common strains of influenza, types A and B, received government approval in October 1999, for the treatment of uncomplicated acute illness due to influenza infection in adults.

Last month, Roche submitted a new Tamiflu indication for the prevention of naturally occurring influenza in adults and adolescents 13 years and older.

The pediatric application is supported by clinical trial data which showed that Tamiflu reduced the duration of influenza by 26 percent in children aged 1-12 when given within two days of onset of symptoms. Additionally, the proportion of patients developing acute otitis media was reduced by 40 percent in children receiving Tamiflu versus those receiving placebo. Children were administered Tamiflu in a tutti fruitti flavored oral suspension formulation.

“Children have a very high incidence of influenza, contracting the disease at a significantly higher rate than adults. However, up until now, influenza has not been adequately treated in this patient population,” said Keith Reisinger, M.D., Pittsburgh Pediatric Research and investigator in the pediatric trials of Tamiflu. “Children readily spread the influenza virus and are very susceptible to secondary complications associated with the disease, such as acute otitis media. Given Tamiflu's convenient mode of administration and good safety profile, it will be of great use to pediatricians, especially in treating children as young as 12 months of age."

Pediatric Studies
The new application is supported by findings from Phase III randomized, double-blind placebo-controlled clinical trials involving 1,029 children aged 1-12 years, including 695 otherwise healthy children aged 1-12 and 334 asthmatic children aged 6-12. In the study involving otherwise healthy children, 69 percent of patients were infected with influenza A and 31 percent with influenza B. In total, 515 patients received the Tamiflu oral suspension formulation.

In the study involving otherwise healthy children, Tamiflu reduced the duration of influenza by 26 percent. Duration of influenza was defined as time to alleviation of cough, nasal congestion, resolution of fever, and return to normal health and activity. This study showed that children receiving Tamiflu returned to normal health and activity almost two days earlier than those receiving placebo.

Tamiflu was well tolerated. The most common adverse event in the pediatric studies was vomiting (approximately 5 percent higher than the placebo group).

"The benefit of Tamiflu in children is consistent with what is seen in the adult population, and is particularly exciting because it meets an unmet medical need for the millions of children who suffer from influenza every season," said Dr. Dominick Iacuzio, Medical Director, Hoffmann-La Roche. "This new indication will allow us to bring a safe and convenient antiviral medication to the entire family."

About Tamiflu
Tamiflu, co-developed by Gilead Sciences of Foster City, California, is a systemic treatment for all common strains of influenza (types A & B). The medication targets one of the two major surface structures of the influenza virus, the neuraminidase protein. The neuraminidase site is virtually the same in all common strains of influenza. If neuraminidase is inhibited, the virus is not able to infect new cells.

In its first season of availability for treatment, Tamiflu has amassed more than 58 percent of the market share within the new class of antivirals called neuraminidase inhibitors, and garnered more than 30 percent of the overall influenza antiviral market.

About Hoffmann-La Roche and Gilead Sciences
Hoffmann-La Roche Inc. (Roche), based in Nutley, N.J., is the U.S. prescription drug unit of the Roche Group, a leading research-based health care enterprise that ranks among the world’s leaders in pharmaceuticals, diagnostics and vitamins.

Roche discovers, develops, manufactures and markets numerous important prescription drugs that enhance people's health, well-being and quality of life. Among the company’s areas of therapeutic interest are: virology, including HIV/AIDS and hepatitis C; infectious diseases, including influenza; cardiology; neurology; oncology; transplantation; dermatology; and metabolic diseases, including obesity and diabetes.

For more information on the Roche pharmaceuticals business in the United States, visit the company’s web site at: http://www.rocheusa.com

Gilead Sciences, Inc., headquartered in Foster City, CA, is an independent biopharmaceutical company that seeks to provide accelerated solutions for patients and the people who care for them. Gilead discovers, develops, manufactures and commercializes proprietary therapeutics for challenging infectious diseases (viral, fungal and bacterial infections) and cancer. Gilead maintains research, development or manufacturing facilities in Foster City, CA; Boulder, CO; San Dimas, CA; Cambridge, UK and Dublin, Ireland and sales and marketing organizations in the United States, Europe and Australia. For more information about Gilead, please visit www.gilead.com.