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                                                              EXHIBIT (a)(8)

THIS ANNOUNCEMENT IS NEITHER AN OFFER TO PURCHASE NOR A SOLICITATION OF AN OFFER
TO SELL SHARES OF TRIANGLE PHARMACEUTICALS, INC. COMMON STOCK. THE OFFER (AS
DEFINED BELOW) DESCRIBED HEREIN IS MADE SOLELY BY THE OFFER TO PURCHASE DATED
DECEMBER 16, 2002, AND THE RELATED LETTER OF TRANSMITTAL AND ANY AMENDMENTS OR
SUPPLEMENTS THERETO, EACH OF WHICH IS BEING DELIVERED TO HOLDERS OF TRIANGLE
COMMON STOCK. THE OFFER IS NOT BEING MADE TO (NOR WILL TENDERS BE ACCEPTED FROM
OR ON BEHALF OF) HOLDERS OF SHARES OF TRIANGLE COMMON STOCK IN ANY JURISDICTION
IN WHICH THE MAKING OF THE OFFER OR THE ACCEPTANCE THEREOF WOULD NOT BE IN
COMPLIANCE WITH THE LAWS OF SUCH JURISDICTION OR ANY ADMINISTRATIVE OR JUDICIAL
ACTION PURSUANT THERETO. THE PURCHASER (AS DEFINED BELOW) MAY, IN ITS
DISCRETION, TAKE SUCH ACTION AS IT MAY DEEM NECESSARY TO MAKE THE OFFER IN ANY
JURISDICTION AND EXTEND THE OFFER TO HOLDERS OF SHARES OF TRIANGLE COMMON STOCK
IN SUCH JURISDICTION. IN THOSE JURISDICTIONS WHERE SECURITIES, BLUE SKY OR OTHER
LAWS REQUIRE THE OFFER TO BE MADE BY A LICENSED BROKER OR DEALER, THE OFFER WILL
BE DEEMED TO BE MADE ON BEHALF OF THE PURCHASER BY GOLDMAN, SACHS & CO., THE
DEALER MANAGER FOR THE OFFER, OR BY ONE OR MORE REGISTERED BROKERS OR DEALERS
LICENSED UNDER THE LAWS OF SUCH JURISDICTION TO BE DESIGNATED BY THE PURCHASER.

                      NOTICE OF OFFER TO PURCHASE FOR CASH
                     ALL OUTSTANDING SHARES OF COMMON STOCK
                                       OF
                         TRIANGLE PHARMACEUTICALS, INC.
                                       BY
                         SIMBOLO ACQUISITION SUB, INC.,
                          A WHOLLY OWNED SUBSIDIARY OF
                              GILEAD SCIENCES, INC.
                                       AT
                               $6.00 NET PER SHARE

Simbolo Acquisition Sub, Inc., a Delaware corporation (the "Purchaser") and a
wholly owned subsidiary of Gilead Sciences, Inc., a Delaware corporation
("Gilead"), is offering to purchase all of the outstanding shares of common
stock, par value $0.001 per share, of Triangle Pharmaceuticals, Inc., a
Delaware corporation ("Triangle"), at a price of $6.00 per share, net to the
seller in cash, without interest thereon (the "Offer Price"), upon the terms
and subject to the conditions set forth in the Offer to Purchase, dated
December 16, 2002 (the "Offer to Purchase"), and the related Letter of
Transmittal which, together with any amendments or supplements thereto,
collectively constitute the "Offer" described herein. Tendering Triangle
stockholders whose shares of Triangle common stock are registered in their
own names and who tender their shares directly to Mellon Investor Services
LLC (the "Depositary") will not be obligated to pay brokerage fees or
commissions in connection with the Offer or, except as set forth in
Instruction 6 of the Letter of Transmittal, transfer taxes on the sale of
shares in the Offer. Stockholders of Triangle who hold their shares of
Triangle common stock through brokers, dealers, banks, trust companies or
other nominees should consult with such institutions to determine whether
they will charge any service fees for tendering such stockholder's shares to
the Purchaser in the Offer. The Purchaser is offering to acquire all of the
shares of Triangle common stock as a first step in Gilead acquiring the
entire equity interest in, and thus control of, Triangle. Following the
purchase of shares of Triangle common stock in the Offer, the Purchaser
intends to complete the Merger described below to enable Gilead to acquire
all of the outstanding shares of Triangle common stock that are not tendered
to and accepted for payment by the Purchaser in the Offer.

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   THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK
        CITY TIME, ON JANUARY 15, 2003, UNLESS THE OFFER IS EXTENDED.

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The Offer is conditioned upon, among other things, there being validly tendered
and not withdrawn in accordance with the terms of the Offer prior to the
Expiration Date (as defined below) of the Offer shares of Triangle common stock
that, together with any shares of Triangle common stock then owned by Gilead or
any wholly owned subsidiary of Gilead (including the Purchaser), represent a
majority of the "Adjusted Outstanding Share Number", which is defined in the
Merger Agreement as the sum of all then-outstanding shares of Triangle common
stock, plus, at the election of Gilead, an additional number of shares of
Triangle common stock up to but not exceeding the aggregate number of shares of
Triangle common stock issuable upon the exercise of any outstanding option that
is vested or is expected to become vested (other than by reason of the Merger)
on or before June 1, 2003, or any warrant or other right to acquire capital
stock of Triangle, or upon the conversion of any convertible security. The
foregoing condition is referred to as the "Minimum Condition" in this Offer to
Purchase. Certain of Triangle's directors and certain additional stockholders
of Triangle have entered into stockholder agreements with Gilead and the
Purchaser pursuant to which they have agreed, in their respective capacities as
stockholders of Triangle, to tender all of their shares of Triangle common
stock, as well as any additional shares of Triangle common stock which they may
acquire (pursuant to Triangle stock options or otherwise), to the Purchaser in
the Offer. The parties to certain of those stockholder agreements have also
agreed to vote all of their shares of Triangle common stock in favor of the
Merger, the execution and delivery by Triangle of the Merger Agreement and the
adoption and approval of the Merger Agreement. As of December 3, 2002, the
stockholders who executed stockholder agreements held in the aggregate
31,574,469 shares of Triangle common stock, which represented approximately 41%
of the outstanding


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shares of Triangle common stock as of that date. The stockholder agreements
provide that they terminate upon any termination of the Merger Agreement.

The Offer is being made pursuant to an Agreement and Plan of Merger, dated as
of December 3, 2002, by and among Gilead, the Purchaser and Triangle (the
"Merger Agreement"), pursuant to which, following the purchase of shares of
Triangle common stock in the Offer and the satisfaction or waiver of certain
conditions, the Purchaser will be merged with and into Triangle (the
"Merger"), with Triangle surviving the Merger as a wholly owned subsidiary of
Gilead. Upon the completion of the Merger, each outstanding share of Triangle
common stock (other than shares owned by Gilead, the Purchaser, Triangle or
any wholly owned subsidiary of Gilead or Triangle, or by any stockholder of
Triangle who is entitled to and properly exercises appraisal rights under
Delaware law) will be converted into the right to receive the price per share
paid in the Offer in cash, without interest thereon.

TRIANGLE'S BOARD OF DIRECTORS HAS, AT A MEETING HELD ON DECEMBER 3, 2002, BY
THE UNANIMOUS VOTE OF ALL DIRECTORS OF TRIANGLE, (i) DETERMINED THAT THE
MERGER AGREEMENT AND THE TRANSACTIONS CONTEMPLATED THEREBY, INCLUDING THE
OFFER AND THE MERGER, ARE IN THE BEST INTERESTS OF TRIANGLE AND ITS
STOCKHOLDERS, (ii) APPROVED THE MERGER AGREEMENT AND THE TRANSACTIONS
CONTEMPLATED THEREBY, INCLUDING THE OFFER AND THE MERGER AND (iii) DECLARED
THAT THE MERGER AGREEMENT IS ADVISABLE. ACCORDINGLY, TRIANGLE'S BOARD OF
DIRECTORS UNANIMOUSLY RECOMMENDS THAT THE STOCKHOLDERS OF TRIANGLE ACCEPT THE
OFFER AND TENDER THEIR SHARES OF TRIANGLE COMMON STOCK TO THE PURCHASER IN
THE OFFER AND, IF REQUIRED, VOTE TO ADOPT THE MERGER AGREEMENT.

On the terms of and subject to the conditions to the Offer, promptly after
the Expiration Date of the Offer, the Purchaser will accept for payment, and
pay for, all shares of Triangle common stock validly tendered to the
Purchaser in the Offer and not withdrawn prior to the Expiration Date of the
Offer. The Purchaser will be deemed to have accepted for payment, and thereby
purchased, shares of Triangle common stock that are validly tendered in the
Offer and not withdrawn prior to the Expiration Date of the Offer as, if and
when the Purchaser gives oral or written notice to the Depositary of the
Purchaser's acceptance for payment of such shares. Payment for shares of
Triangle common stock that are accepted for payment in the Offer will be made
by deposit of the purchase price therefor with the Depositary, which will act
as agent for stockholders tendering shares in the Offer for the purpose of
receiving payment from the Purchaser and transmitting payment to such
stockholders whose shares of Triangle common stock have been accepted for
payment in the Offer. For a stockholder to validly tender shares of Triangle
common stock in the Offer (i) the certificate(s) representing the tendered
shares, together with the Letter of Transmittal, properly completed and duly
executed, together with any required signature guarantees and any other
required documents, must be received by the Depositary prior to the
Expiration Date of the Offer, (ii) in the case of a tender effected pursuant
to the book-entry transfer procedures (a) either a Letter of Transmittal,
properly completed and duly executed, together with any required signature
guarantees, or an Agent's Message (as defined in Section 2 of the Offer to
Purchase), and any other required documents, must be received by the
Depositary prior to the Expiration Date of the Offer and (b) the shares to be
tendered must be delivered pursuant to the book-entry transfer procedures
described in the Offer to Purchase and a Book-Entry Confirmation (as defined
in Section 2 of the Offer to Purchase) must be received by the Depositary
prior to the Expiration Date of the Offer or (iii) the tendering stockholder
must comply with the guaranteed delivery procedures described in the Offer to
Purchase prior to the Expiration Date of the Offer.

UNDER NO CIRCUMSTANCES WILL INTEREST BE PAID ON THE OFFER PRICE FOR SHARES OF
TRIANGLE COMMON STOCK THAT ARE TENDERED IN THE OFFER, REGARDLESS OF ANY
EXTENSION OF, OR AMENDMENT TO, THE OFFER OR ANY DELAY IN PAYING FOR SUCH
SHARES.

For purposes of the Offer and as used herein and in the Offer to Purchase,
the term "Expiration Date" means 12:00 midnight, New York City time, on
January 15, 2003, unless and until the Purchaser extends the period of time
during which the Offer is open in accordance with the terms of the Merger
Agreement, in which event the term "Expiration Date" will mean the latest
time at which the Offer, as so extended by the Purchaser, will expire. Under
the terms of the Merger Agreement, upon the written request of Triangle prior
to January 15, 2003, the Purchaser is obligated to extend the Offer, by
giving oral or written notice of such extension to the Depositary, for such
period of time (not more than 15 business days) as Triangle reasonably
requests if the Minimum Condition or any other condition provided for in the
Merger Agreement (the "Offer Conditions") has not been satisfied or waived by
12:00 midnight, Eastern Standard Time, on January 15, 2003, the initial
Expiration Date of the Offer. In addition, if on any subsequent date as of
which the Offer is scheduled to expire, any of the Offer Conditions has not
been satisfied or waived, the Purchaser shall, if Triangle so requests in
writing prior to the then-scheduled Expiration Date of the Offer, extend the
Offer from time to time for such period of time (but in each case not more
than 15 business days) as Triangle reasonably requests.

If the Purchaser extends the Offer, the Purchaser will inform the Depositary
of that fact and will make a public announcement of the extension not later
than 9:00 a.m., Eastern Standard Time, on the next business day after the
previously scheduled Expiration Date of the Offer. During any such extension,
all shares of Triangle common stock previously tendered and not withdrawn
will remain subject to the Offer, subject to the right of a tendering
stockholder to withdraw such shares. Shares of Triangle common stock that are
tendered in the Offer may be withdrawn pursuant to the procedures described
in the Offer to Purchase at any time prior to the Expiration Date of the
Offer, and shares that are tendered may also be withdrawn at any time after
February 14, 2003 unless accepted for payment on or before that date. In the
event that the Purchaser provides for a subsequent offering period following
the successful completion of the Offer, (i) no withdrawal rights will apply
to shares tendered during such subsequent offering period and (ii) no
withdrawal rights will apply to shares that were previously tendered in the
Offer and accepted for payment.

For a withdrawal of shares of Triangle common stock previously tendered in
the Offer to be effective, a written or facsimile transmission notice of
withdrawal must be timely received by the Depositary at one of its addresses
listed on the back cover of the Offer to Purchase, specifying the name of the
person having tendered the shares to be withdrawn, the number of shares to be
withdrawn and the name of the registered holder of the shares to be
withdrawn, if different from the name of the person who tendered the shares.
If certificates for shares have been delivered or otherwise identified to the
Depositary, then, prior to the physical release of such certificates, the
serial numbers shown on such certificates must be submitted to the



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Depositary and, unless such shares have been tendered by a financial
institution (including most banks, savings and loan associations and
brokerage houses) that is a participant in the Security Transfer Agent's
Medallion Program, Nasdaq Stock Market Medallion Signature Guarantee Program
or the Stock Exchange Medallion Program (each an "Eligible Institution"), any
and all signatures on the notice of withdrawal must be guaranteed by an
Eligible Institution. If shares have been tendered pursuant to the book-entry
transfer procedures described in Section 2 of the Offer to Purchase, any
notice of withdrawal must also specify the name and number of the account at
the Book-Entry Transfer Facility (as defined in Section 2 of the Offer to
Purchase) to be credited with the withdrawn shares and otherwise comply with
the Book-Entry Transfer Facility's procedures. Withdrawals of tenders of
shares may not be rescinded, and any shares withdrawn will thereafter be
deemed not validly tendered for purposes of the Offer. Withdrawn shares may
be re-tendered in the Offer, however, by following one of the procedures
described in Section 2 of the Offer to Purchase at any time prior to the
Expiration Date of the Offer. All questions as to the form and validity
(including time of receipt) of any notice of withdrawal will be determined by
the Purchaser in its sole discretion, which determination will be final and
binding. None of the Purchaser, Gilead, Triangle, Goldman, Sachs & Co., the
dealer manager for the Offer (the "Dealer Manager"), the Depositary,
Georgeson Shareholder Communciations Inc., the information agent for the
Offer (the "Information Agent"), or any other person will be under any duty
to give notification of any defects or irregularities in any notice of
withdrawal or incur any liability for failure to give any such notification.

Under Rule 14d-11 of the Securities Exchange Act of 1934, as amended, and
subject to conditions described in the Offer to Purchase, the Purchaser may
elect to provide for a subsequent offering period, immediately following the
Expiration Date of the Offer, of not less than three business days nor more
than twenty business days in length. If provided, a subsequent offering
period would be an additional period of time, following the Expiration Date
of the Offer and the acceptance for payment of, and the payment for, any
shares of Triangle common stock that are validly tendered in the Offer and
not withdrawn prior to the Expiration Date of the Offer, during which holders
of shares of Triangle common stock that were not previously tendered in the
Offer may tender such shares to the Purchaser in exchange for the Offer Price
on the same terms that applied to the Offer. A subsequent offering period is
not the same as an extension of the Offer, which will have been previously
completed if a subsequent offering period is provided. The Purchaser will
accept for payment, and pay for, any shares of Triangle common stock that are
validly tendered to the Purchaser during a subsequent offering period, if
provided, as promptly as practicable after any such shares are validly
tendered to the Purchaser during such subsequent offering period, for the
same price paid to holders of shares of Triangle common stock that were
validly tendered in the Offer and not withdrawn prior to the Expiration Date
of the Offer, net to the holders thereof in cash. Holders of shares of
Triangle common stock that are validly tendered to the Purchaser during a
subsequent offering period, if provided, will not have the right to withdraw
such tendered shares.

Triangle has provided the Purchaser with a list, and security position
listings, of Triangle's stockholders for the purpose of disseminating the
Offer to holders of shares of Triangle common stock. The Offer to Purchase,
and the Letter of Transmittal and other materials related to the Offer will
be mailed to record holders of shares of Triangle common stock, and will be
furnished to brokers, dealers, banks, trust companies and other nominees
whose names, or the names of whose nominees, appear on the list of Triangle's
stockholders, or, if applicable, who are listed as participants in a clearing
agency's security position listing, for subsequent transmittal to beneficial
owners of shares of Triangle common stock.

The receipt of cash in the Offer or the Merger will be a taxable transaction
for United States federal income tax purposes under the Internal Revenue Code
of 1986, as amended, and may also be a taxable transaction under applicable
state, local or foreign income or other tax laws. Generally, for U.S. federal
income tax purposes, a U.S. stockholder tendering shares of Triangle common
stock in the Offer will recognize gain or loss equal to the difference
between the amount of cash received by the stockholder in the Offer or the
Merger and the stockholder's aggregate adjusted tax basis in the shares
tendered by the stockholder and accepted for payment in the Offer or
converted into cash in the Merger, as the case may be. If shares of Triangle
common stock that are tendered in the Offer are held by a tendering U.S.
stockholder as capital assets, gain or loss recognized by such stockholder
will be capital gain or loss, which will be long-term capital gain or loss if
such stockholder's holding period for such shares exceeds one year. All
stockholders should consult with their own tax advisors as to the particular
tax consequences of the Offer and the Merger to them, including the
applicability and effect of the alternative minimum tax and any state, local
or foreign income and other tax laws and of changes in such tax laws. For a
more complete description of certain U.S. federal income tax consequences of
the Offer and the Merger, see Section 5 of the Offer to Purchase.

The Purchaser expressly reserves the right (but shall not be obligated), at
any time and from time to time, to increase the Offer Price or to make any
other changes in the terms of and conditions to the Offer, subject to the
terms of the Merger Agreement, which provides that certain conditions may not
be waived and certain modifications may not be made without the consent of
Triangle.

The information required to be disclosed by paragraph (d)(1) of Rule 14d-6 of
the General Rules and Regulations under the Securities Exchange Act of 1934,
as amended, is contained in the Offer to Purchase and is incorporated herein
by reference.

THE OFFER TO PURCHASE AND LETTER OF TRANSMITTAL CONTAIN IMPORTANT INFORMATION
AND SHOULD BE READ CAREFULLY AND IN THEIR ENTIRETY BEFORE ANY DECISION IS
MADE WITH RESPECT TO THE OFFER.

Questions regarding the Offer, and requests for assistance in connection with
the Offer, may be directed to the Dealer Manager or the Information Agent as
set forth below. Requests for copies of the Offer to Purchase, the Letter of
Transmittal and all other materials related to the Offer may be directed to
the Information Agent or the Dealer Manager, as set forth below, or brokers,
dealers, banks, trust companies or other nominees, and copies will be
furnished promptly at the Purchaser's expense. No fees or commissions will be
payable to brokers, dealers or other persons (other than the Dealer Manager
and Information Agent, as described in the Offer to Purchase) for soliciting
tenders of shares of Triangle common stock in the Offer.

                     THE INFORMATION AGENT FOR THE OFFER IS:



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                    GEORGESON SHAREHOLDER COMMUNICATIONS INC.
                           17 STATE STREET, 10TH FLOOR
                               NEW YORK, NY 10004

                 BANKS AND BROKERS CALL COLLECT: (212) 440-9800
                    ALL OTHERS CALL TOLL FREE: (866) 295-4328

                      THE DEALER MANAGER FOR THE OFFER IS:

                              GOLDMAN, SACHS & CO.
                                 85 BROAD STREET
                            NEW YORK, NEW YORK 10004

                          CALL COLLECT: (212) 902-1000
                         CALL TOLL FREE: (800) 323-5678

December 16, 2002

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