July 11, 2002

48-Week Data Demonstrate Ability of Viread to Suppress Viral Load in Patients With Multiple Treatment-Resistant HIV Mutations

Results of Genotypic and Phenotypic Analyses from Two Studies Presented at International AIDS Conference in Barcelona

These data, which further characterize the resistance profile of Viread, were described in an oral presentation (#1390) by Michael Miller, PhD, Director of Clinical Virology, Gilead Sciences, at the XIV International AIDS Conference in Barcelona. This presentation is one of 16 Viread abstracts to be featured at the conference.

"Resistance to available antiretrovirals is among the most serious treatment challenges facing physicians and their patients," commented Dr. Miller. "We have extensively evaluated the resistance profile of Viread, and will continue to invest in this important research to provide treating physicians with additional information that will help them to construct optimal regimens for their HIV patients."

    HIV Resistance Analysis

Patients with no TAMs who received the Viread-containing regimen experienced a significant reduction in mean HIV RNA level of 0.80 log10 copies/mL at 24 weeks (p less than 0.001; n=68). In patients with one to two TAMs, the mean HIV RNA level was reduced by a level comparable to that of the overall Viread treatment population at 24 weeks (reduction of 0.66 log10 copies/mL, p less than 0.001; n=55). Patients with three or more TAMs not including M41L or L210W experienced a mean reduction in HIV RNA level of 0.67 log10 copies/mL at 24 weeks, consistent with the overall Viread treatment population and significantly superior to placebo (p less than 0.001; n=42). In patients with three or more TAMs that included M41L or L210W, the susceptibility of HIV to Viread combination treatment was less, with a demonstrated mean HIV RNA level reduction of 0.21 log10 copies/mL at 24 weeks. This result was statistically significantly superior to the response in patients receiving placebo in addition to their existing combination therapy (p=0.013; n=57).

           HIV RNA Response at Week 24 by Number and Type of
     Baseline Thymidine Analogue Mutations in Studies 902 and 907
                         (Intent-To-Treat)(1)
Number of baseline               VIREAD                P-value
thymidine analogue         Change in HIV RNA(3)(N)   versus Placebo
mutations(2)
None                            -0.80 (68)           p less than 0.001
1 - 2                           -0.66 (55)           p less than 0.001
greater than or
 equal to 3 without
 M41L or L210W                  -0.67 (42)           p less than 0.001
greater than or
 equal to 3 including
 M41L or L210W                  -0.21 (57)           p=0.013
1.  Genotypic testing performed by Virco Laboratories and Visible
    Genetics TruGene(TM) technology
2.  M41L, D67N, K70R, L210W, T215Y/F or K219Q/E/N in RT
3.  Average HIV RNA change from baseline through week 24 (DAVG24) in
    log10 copies/mL
    About HIV Drug Resistance
    About Study 902
    About Study 907

Upon entry, patients were randomized (2:1) to receive Viread or placebo in addition to their existing antiretroviral therapy. After 24 weeks of blinded, placebo-controlled dosing, all patients were switched to receive open-label Viread for the remainder of the 48-week study period.

Forty-eight week efficacy and safety results from Study 907 were discussed yesterday in an oral presentation (#1266) by Anton Pozniak, MD, Chelsea and Westminster Hospital, London, United Kingdom.

    About Viread

In the United States, Viread is indicated for use in combination with other antiretroviral agents for the treatment of HIV-1 infection. This indication is based on analyses of plasma HIV-1 RNA levels and CD4 cell counts in a controlled study of Viread of 24 weeks duration and in a controlled, dose-ranging study of Viread of 48 weeks duration. Both studies were conducted in treatment-experienced adults with evidence of HIV-1 viral replication despite ongoing antiretroviral therapy. Studies in antiretroviral-naive patients are ongoing; consequently, the risk-benefit ratio for this population has yet to be determined.

Viread is approved in Europe for use in combination with other antiretroviral agents for the treatment of HIV infection in patients who are experiencing early virological failure.

    Resistance Profile
    Safety Profile

The most common adverse events in patients receiving Viread were mild to moderate gastrointestinal events, such as nausea, diarrhea, vomiting and flatulence. Laboratory abnormalities observed in clinical studies occurred with similar frequency in the Viread and placebo-treated groups. Lactic acidosis and severe hepatomegaly with steatosis, including fatal cases, have been reported with the use of nucleoside analogues alone or in combination with other antiretrovirals.

    Ongoing Clinical Studies
    About HIV/AIDS
    About Gilead Sciences

This press release includes forward-looking statements, within the meaning of the Private Securities Litigation Reform Act of 1995 that are subject to risks, uncertainties and other factors that could cause actual results to differ materially from those referred to in the forward-looking statements. Such risks and uncertainties include the risk that these data will not be observed through longer treatment periods. The reader is cautioned not to rely on these forward-looking statements. These and other risks are described in detail in the Gilead Annual Report on Form 10-K for the year ended December 31, 2001 and in Gilead's Quarterly Reports on Form 10-Q, all of which are on file with the U.S. Securities and Exchange Commission. All forward-looking statements are based on information currently available to Gilead and Gilead assumes no obligation to update any such forward-looking statements.

    For complete prescribing information, please visit www.viread.com.

For more information on Gilead Sciences, please visit the company's web site at www.gilead.com or call the Gilead Corporate Communications Department at 1-800-GILEAD-5 or 1-650-574-3000.

CONTACT:          Gilead Sciences, Inc.                        
                  Susan Hubbard, 650/522-5715 (Investors)      
                  Amy Flood, 44-7715-809-567 (Media)           

URL:              http://www.businesswire.com
Today's News On The Net - Business Wire's full file on the Internet
with Hyperlinks to your home page.
Copyright (C) 2002 Business Wire.  All rights reserved.

Other News

Some of the content on this page is not intended for users outside the U.S.