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[LOGO OF GILEAD]                              [LOGO OF TRIANGLE PHARMACEUTICALS]

GILEAD CONTACTS:                              TRIANGLE CONTACT:
Susan Hubbard, Investors                      R. Andrew Finkle
(650) 522-5715                                (919) 493-5980

Amy Flood, Media
(650) 522-5643

              GILEAD SCIENCES AND TRIANGLE PHARMACEUTICALS ANNOUNCE
                 EXPIRATION OF HART-SCOTT-RODINO WAITING PERIOD

FOSTER CITY, CA, AND DURHAM, NC, DECEMBER 26, 2002 - Gilead Sciences, Inc.
(Nasdaq: GILD) and Triangle Pharmaceuticals, Inc. (Nasdaq: VIRS) today
announced that the required waiting period under the Hart-Scott-Rodino
Antitrust Improvements Act of 1976 with respect to Gilead's cash tender offer
for Triangle has expired without any request for additional information by
the United States Federal Trade Commission.

The transaction is expected to close in the first quarter of 2003, subject to
customary closing conditions.  This announcement is neither an offer to
purchase nor a solicitation of an offer to sell Triangle shares.  The tender
offer can only be made through an offer to purchase, letter of transmittal
and related tender offer materials.  The tender offer materials, certain
other offer materials, and the solicitation/recommendation statement have
been sent to all stockholders of Triangle and also are available free of
charge at the SEC's website at www.sec.gov.

ABOUT GILEAD SCIENCES
Gilead Sciences is a biopharmaceutical company that discovers, develops and
commercializes therapeutics to advance the care of patients suffering from
life-threatening diseases worldwide.  The company has six marketed products
and focuses its research and clinical programs on anti-infectives.
Headquartered in Foster City, CA, Gilead has operations in the United States,
Europe and Australia.

ABOUT TRIANGLE PHARMACEUTICALS
Triangle Pharmaceuticals, Inc. is a specialty pharmaceutical company engaged
in the development of new antiviral drug candidates, with a particular focus
on therapies for the human immunodeficiency virus (HIV) and the hepatitis B
virus. Triangle's proprietary drug candidates under development for HIV
and/or hepatitis B include Coviracil(R) (emtricitabine), amdoxovir (formerly
DAPD) and clevudine (formerly L-FMAU).

This press release includes forward-looking statements 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.
For example, the ability of the parties to close the transaction by the end
of the first quarter of 2003 will depend on a number of factors outside the
parties' control including the satisfaction of closing conditions.  These
risks are described in Gilead's Report on Form 8-K filed with the U.S.
Securities and Exchange Commission on December 10, 2002.  All forward-looking
statements are based on information currently available, and the parties
assume no obligation to update any such forward-looking statements.

                                      # # #

                         For more information on Gilead,
               please call the Gilead Public Affairs Department at
            1-800-GILEAD-5 (1-800-445-3235) or visit www.gilead.com.

        For more information on Triangle, please visit www.tripharm.com.