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                                                                    EXHIBIT 99.1

CONTACT:

Mr. Robert Amundsen                           Mr. Chris Rallis
I. Executive Vice President, Chief            President, Chief Operating Officer
Financial Officer

Triangle Pharmaceuticals, Inc.                Triangle Pharmaceuticals, Inc.
(919) 493-5980                                (919) 493-5980

WWW.TRIPHARM.COM                              WWW.TRIPHARM.COM

FOR IMMEDIATE RELEASE:

Triangle Pharmaceuticals Plans 3rd Quarter 2002 NDA Submission for Coviracil(R)
(emtricitabine) and Discontinues Development of Coactinon(R)(emivirine)

DURHAM, N.C., JANUARY 17, 2002. -- Triangle Pharmaceuticals, Inc. (Nasdaq: VIRS)
today provided updated information on the development of two of its HIV
compounds, Coviracil and Coactinon.

Following recent discussions with the FDA, Triangle now plans to submit a New
Drug Application (NDA) early this fall for Coviracil in the treatment of HIV.
The Company expects Coviracil to become its first product for which an NDA is
submitted, marking a critical milestone in the Company's history.

Triangle further intends to terminate development of Coactinon, another of its
HIV compounds. The Company recently completed a planned interim analysis of
24-week data from study MKC-401. Although the results of this interim analysis
did not trigger the pre-defined criteria for stopping the study, the interim
analysis indicated that Coactinon was not performing as well as its comparator
drug, abacavir, across the full study population. Therefore, Triangle has
elected to discontinue development of Coactinon and allocate the Company's
personnel and other resources to more promising drug candidates within its
portfolio. Those drug candidates include: (1) Coviracil, for which a 3rd quarter
NDA submission is planned for the treatment of HIV disease and a pivotal trial
is ongoing in the treatment of hepatitis B infection; (2) amdoxovir (DAPD), for
which the Company plans to initiate several Phase II trials in HIV during 2002;
and (3) clevudine (L-FMAU), which is currently in an ongoing Phase I/II study in
the treatment of hepatitis-B infection and for which a Phase II program is
planned to be commenced during 2002. Triangle will provide a full update on
these programs and the Company's 2002 financial and operating plans in
conjunction with its earnings release scheduled for early February 2002.

"We are very pleased to be in a position to submit the Coviracil NDA in the
third quarter of this year," stated Dr. David Barry, Chairman and CEO of
Triangle. Dr. Barry
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continued, "With the expected Coviracil NDA submission now only two quarters
away, we must prioritize our efforts and resources to ensure that this timeline
is met, and to advance the most promising programs in our pipeline as
aggressively as possible."

Triangle stands to receive potential reimbursement milestones from Abbott
Laboratories of up to $85 million upon obtaining regulatory approval and the
launch of Coviracil for the treatment of HIV in the U.S. and Europe. In
addition, despite the termination of the Coactinon program, Triangle stands to
receive additional potential reimbursement milestones of up to $35 million upon
obtaining regulatory approvals of amdoxovir and clevudine in the U.S. Under a
1999 agreement, Triangle and Abbott have joint rights to commercialize
Coviracil, amdoxovir, and clevudine in the U.S. Outside the U.S., Abbott will
have exclusive commercialization rights for these drug candidates.

The Company will hold a conference call on Friday, January 18, 2002 at 11:30
a.m. EST. Interested parties in the U.S. may join the call by dialing toll free
877-679-9055. International callers may dial 952-556-2808. The confirmation
number is 5788516 and the moderator is Dr. David Barry. The call will be Webcast
on the Triangle Pharmaceuticals Web site at WWW.TRIPHARM.COM and archived for
replay on the site for one week after the call.

Triangle Pharmaceuticals is engaged in the development of new antiviral drug
candidates, with a particular focus on therapies for the human immunodeficiency
virus (HIV) and hepatitis. Triangle's proprietary drug candidates under
development for HIV and/or hepatitis include Coviracil(R) (emtricitabine),
amdoxovir and clevudine. Triangle is also developing immunotherapies for HIV and
hepatitis in collaboration with Dynavax Technology Corporation utilizing
Dynavax' ImmunoStimulatory Sequence (ISS) technology. More information about
Triangle's portfolio, management and product development strategy is available
on Triangle's website at: WWW.TRIPHARM.COM.

Statements in this press release that are not historical facts are
forward-looking statements and are subject to numerous risks and uncertainties,
including the fact that clinical trials for our drug candidates may not proceed
as planned and regulatory submissions for our drug candidates may be delayed.
Additionally, other risks include the fact that the Company may be unable to
successfully complete pivotal clinical trials or that its trials could be halted
or terminated by regulatory authorities, the Company may be unable to
commercialize Coviracil, DAPD and ISS-based therapies due to patent rights held
by third parties, that cash usage targets may not be met for a number of
reasons, including the risk that changes in our drug development strategies or
unpredictable events may impact the timing and degree of actual spending, the
Company's ability to obtain additional funding (including contingent contractual
milestone payments), patent protection and required regulatory approvals for its
drug
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candidates, the development of competitive products by others, the cost of
coactive therapy and the extent to which coactive therapy achieves market
acceptance, the Company's success in identifying new drug candidates, acquiring
rights to the candidates on favorable terms and developing any candidates to
which the Company acquires any rights, and that the Company's collaborations
with third parties may not prove successful. These and other risks are discussed
in detail from time to time in the Company's filings with the Securities and
Exchange Commission. As a result of these and other risks and uncertainties,
actual results may differ materially from those predicted in this press release.
The Company disclaims any obligations to update any forward-looking statements
in this press release.