<PAGE>

     AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON October 31, 1996
                                          REGISTRATION NO. 333-___________

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------


                          SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C. 20549

                                ---------------------


                                       FORM S-8
                                REGISTRATION STATEMENT
                                        UNDER
                              THE SECURITIES ACT OF 1933

                            TRIANGLE PHARMACEUTICALS, INC.
                  (Exact name of issuer as specified in its charter)

             DELAWARE                                    56-1930728             
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
incorporation or organization)

                      4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE
                             DURHAM, NORTH CAROLINA 27707
                  (Address of Principal Executive Office) (Zip Code)
                                ----------------------
                              1996 STOCK INCENTIVE PLAN
                             EMPLOYEE STOCK PURCHASE PLAN
                              (Full title of the plans)
                                ----------------------
                                  DR. DAVID W. BARRY
                         Chairman and Chief Executive Officer
                            TRIANGLE PHARMACEUTICALS, INC.
                      4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE
                     DURHAM, NORTH CAROLINA 27707  (919) 493-5980
(Name, address and telephone number, including area code, of agent for service)
                                ----------------------
                                      Copies to:
                               John A. Denniston, Esq.
                                  John R. Cook, Esq.
                           BROBECK, PHLEGER & HARRISON LLP
                            550 West C Street, Suite 1300
                             San Diego, California  92101
                                    (619) 234-1966
                                ----------------------
            This Registration Statement shall become effective immediately
               upon filing with the Securities and Exchange Commission
              and sales of the registered securities will begin as soon
                 as reasonably practicable after such effective date.
                                ---------------------

                           CALCULATION OF REGISTRATION FEE
 

<TABLE>
<CAPTION>
------------------------------------------------------------------------------------------
                                            Proposed       Proposed                    
                                             maximum       maximum                     
Title of                                     offering     aggregate          Amount of 
securities to           Amount to be          price        offering        registration
be registered            registered         per share       price               fee    
------------------------------------------------------------------------------------------
<S>                     <C>                 <C>         <C>                <C>         
Common Stock, $0.001    1,882,667(1)         $9.50(2)   $17,885,337(2)           $5,420
par value per share                                                                    
(under 1996                                                                            
Stock Incentive Plan)                                                                  

Common Stock, $0.001      300,000(1)         $9.50(2)    $2,850,000(2)             $864
par values per share                                                                   
(under Employee                                                                   
Stock Purchase Plan)                                                                   

</TABLE>
 

--------------------
(1)  This Registration Statement shall also cover any additional shares of
Common Stock which become issuable under the 1996 Stock Incentive Plan and
the Employee Stock Purchase Plan by reason of any stock dividend, stock split,
recapitalization or other similar transaction effected without  the receipt of
consideration which results in an increase in the number of the Company's
outstanding shares of Common Stock.
(2)  Estimated solely for the purposes of computing the amount of registration
fee in accordance with Rule 457(c) under the Securities Act of 1933, as amended.

<PAGE>

                                       PART II

                  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.
    
    Triangle Pharmaceuticals, Inc. (the "Registrant" or "Company") hereby
incorporates by reference into this Registration Statement the following
document previously filed with the Securities and Exchange Commission (the
"Commission"):

    (a)  the Registrant's Prospectus filed September 11, 1996 with the
    Registrant's Registration Statement No. 333-11793 on Form S-1, as amended,
    under the Securities Act of 1933, as amended (the "Securities Act"), in
    which there is set forth the Registrant's audited financial statements for
    the period from the Registrant's inception (July 12, 1995) to December 31,
    1995.

    (b)  the Registrant's Registration Statement on Form 8-A filed October 18,
    1996, with the Commission pursuant to Section 12 of the Securities Exchange
    Act of 1934, as amended (the "Exchange Act"), in which there is described
    the terms, rights and provisions applicable to the Registrant's outstanding
    Common Stock. 

    All documents filed by Registrant pursuant to Section 13(a), 13(c), 14 or
15(d) of the Exchange Act after the date of this Registration Statement and
prior to the filing of a post-effective amendment which indicates that all
securities offered hereby have been sold or which deregisters all securities
then remaining unsold, shall be deemed to be incorporated by reference into this
Registration Statement and to be a part hereof from the date of filing of such
documents.

Item 4.  DESCRIPTION OF SECURITIES

         Not applicable.

Item 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

    The validity of the Common Stock offered hereby will be passed upon for the
Company by Brobeck, Phleger & Harrison LLP, San Diego, California.  A member of
such firm owns a total of 13,333 shares of the Company's Common Stock.

Item 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

    Section 145 of the Delaware General Corporation Law permits indemnification
of officers and directors of the Company under certain conditions and subject to
certain limitations.  Section 145 of the Delaware General Corporation Law also
provides that a corporation has the power to purchase and maintain insurance on
behalf of its officers and directors against any liability asserted against such
person and incurred by him or her in such capacity, or arising out of his or her
status as such, whether or not the corporation would have the power to indemnify
him or her against such liability under the provisions of Section 145 of the
Delaware General Corporation Law.

    Article VII, Section (i) of the Restated Bylaws of the Company provides
that the Company shall indemnify its directors and executive officers to the
fullest extent not prohibited by the Delaware General Corporation Law. The
rights to indemnity thereunder continue as to a person who has ceased to be a
director, officer, employee or agent and inure to the benefit of the heirs,
executors and administrators of the person.  In addition, expenses incurred by a
director or officer in defending any civil, criminal, administrative


                                         II-1

<PAGE>

or investigative action, suit or proceeding by reason of the fact that he or
she is or was a director or officer of the Company (or was serving at the
Company's request as a director or officer of another corporation), shall be
paid by the Company in advance of the final disposition of such action, suit or
proceeding upon receipt of an undertaking by or on behalf of such director or
officer to repay such amount if it shall ultimately be determined that he or she
is not entitled to be indemnified by the Company as authorized by the relevant
section of the Delaware General Corporation Law.

    As permitted by Section 102(b)(7) of the Delaware General Corporation Law,
Article 5, Section (a) of the Company's Second Restated Certificate of
Incorporation provides that a director of the Company shall not be personally
liable for monetary damages for breach of fiduciary duty as a director, except
for liability (i) for any breach of the director's duty of loyalty to the
Company or its stockholders, (ii) for acts or omissions not in good faith or
acts or omissions that involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the Delaware General Corporation Law or (iv) for
any transaction from which the director derived any improper personal benefit.

    The Company has entered into indemnification agreements with each of its
officers and directors.  Generally, the indemnification agreements attempt to
provide the maximum protection permitted by Delaware law as it may be amended
from time to time.  Under such additional indemnification provisions, however,
an individual will not receive indemnification for judgments, settlements or
expenses if he or she is found liable to the Company (except to the extent the
court determines he or she is fairly and reasonably entitled to indemnity for
expenses), for settlements not approved by the Company or for settlement and
expenses if the settlement is not approved by the court.  The indemnification
agreements provide for the Company to advance to the individual any and all
reasonable expenses (including legal fees and expenses) incurred in
investigating or defending any such action, suit or proceeding.  In order to
receive an advance of expenses, the individual must submit to the Company copies
of invoices presented to him or her for such expenses.  Also, the individual
must repay such advances upon a final judicial decision that he or she is not
entitled to indemnification.

    The Company has also purchased directors' and officers' liability 
insurance.

Item 7.  EXEMPTION FROM REGISTRATION CLAIMED

         Not Applicable.

                                         II-2

<PAGE>
Item 8.  EXHIBITS

Exhibit Number        Exhibit
--------------        -------

     *4.1        Second Restated Certificate of Incorporation of the Company   
                 (Exhibit 3.2).
     *4.2        Restated Bylaws of the Company (Exhibit 3.4).
     +4.3        Form of Certificate for Common Stock (Exhibit 4.1).
      5.1        Opinion and consent of Brobeck, Phleger & Harrison LLP.
     23.1        Consent of Brobeck, Phleger & Harrison LLP (contained in 
                 Exhibit 5.1).
     23.2        Consent of Independent Accountants, Price Waterhouse LLP.
    *99.1        1996 Stock Incentive Plan (Exhibit 10.35).
    *99.2        1996 Stock Incentive Plan Form of Notice of Grant (Exhibit 
                 10.36).
    *99.3        1996 Stock Incentive Plan Form of Stock Option Agreement 
                 (Exhibit  10.37).
    *99.4        Employee Stock Purchase Plan (Exhibit 10.38).

-------------------

*   These exhibits were previously filed as part of, and are hereby
    incorporated by reference to, the same numbered exhibit (except as
    otherwise noted) filed with the Company's Registration Statement on Form 
    S-1 (Commission No. 333-11793) filed on September 11, 1996.

+   These exhibits were previously filed as part of, and are hereby 
    incorporated by reference to, the same numbered exhibit (except as 
    otherwise noted) filed with the Company's Amendment No. 2 to Registration 
    Statement on Form S-1 (Commission No. 333-11793) filed on October 23, 1996.




Item 9.  UNDERTAKINGS

         A.  The undersigned Registrant hereby undertakes:  (1) to file, during
any period in which offers or sales are being made, a post-effective amendment
to this Registration Statement (i) to include any prospectus required by
Section 10(a)(3) of the Securities Act of 1933, (ii) to reflect in the
prospectus any facts or events arising after the effective date of this
Registration Statement (or the most recent post-effective amendment thereof)
which, individually or in the aggregate, represent a fundamental change in the
information set forth in this Registration Statement, and (iii) to include any
material information with respect to the plan of distribution not previously
disclosed in this Registration Statement or any material change to such
information in this Registration Statement; PROVIDED, HOWEVER, that
clauses (1)(i) and (1)(ii) shall not apply if the information required to be
included in a post-effective amendment by those clauses is contained in periodic
reports filed by the Registrant pursuant to Section 13 or Section 15(d) of the
Securities Exchange Act of 1934 that are incorporated by reference into this
Registration Statement; (2) that for the purpose of determining any liability
under the Securities Act of 1933, each such post-effective amendment shall be
deemed to be a new registration statement relating to the securities offered
therein and the offering of such securities at that time shall be deemed to be
the initial BONA FIDE offering thereof; and (3) to remove from registration by
means of a post-effective amendment any of the securities being registered which
remain unsold upon the termination of the offering.

         B.  The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (and, where applicable, each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of
1934) that is incorporated by reference in the registration statement shall be
deemed to be a new registration statement relating to the securities offered
therein, and the offering of such securities at that time shall be deemed to be
the initial BONA FIDE offering thereof.

         C.  Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers or controlling
persons of the Registrant pursuant to the indemnity provisions incorporated by
reference in Item 6, or otherwise, the Registrant has been informed that in the
opinion of

                                         II-3

<PAGE>

the Securities and Exchange Commission such indemnification is against public
policy as expressed in the 1933 Act and is, therefore, unenforceable.  In the
event that a claim for indemnification against such liabilities (other than the
payment by the Registrant of expenses incurred or paid by a director, officer or
controlling person of the Registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the Registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the 1933 Act
and will be governed by the final adjudication of such issue.
 
                                         II-4

<PAGE>
                                      SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8, and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Durham, State of North Carolina, on this 
31st day of October, 1996.

                                       TRIANGLE PHARMACEUTICALS, INC.


                                       By  /s/ David W. Barry
                                          ------------------------------------
                                          DAVID W. BARRY
                                          Chairman and Chief Executive Officer 


                                  POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS:

         That the undersigned officers and directors of Triangle
Pharmaceuticals, Inc. a Delaware corporation, do hereby constitute and appoint
David W. Barry and James A. Klein, Jr., and each of them, the lawful attorneys-
in-fact and agents with full power and authority to do any and all acts and
things and to execute any and all instruments which said attorneys and agents,
and either one of them, determine may be necessary or advisable or required to
enable said corporation to comply with the Securities Act of 1933, as amended,
and any rules or regulations or requirements of the Securities and Exchange
Commission in connection with this Registration Statement.  Without limiting the
generality of the foregoing power and authority, the powers granted include the
power and authority to sign the names of the undersigned officers and directors
in the capacities indicated below to this Registration Statement, to any and all
amendments, both pre-effective and post-effective, and supplements to this
Registration Statement, and to any and all instruments or documents filed as
part of or in conjunction with this Registration Statement or amendments or
supplements thereof, and each of the undersigned hereby ratifies and confirms
that all said attorneys and agents, or either of them, shall do or cause to be
done by virtue hereof.  This Power of Attorney may be signed in several
counterparts.

         IN WITNESS WHEREOF, each of the undersigned has executed this Power of
Attorney as of the date indicated.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons in the
capacities and on the dates indicated.

Signature                    Title                              Date
---------                    -----                              ----

/s/ David W. Barry           Chairman of the Board and Chief   October 31, 1996
-------------------------    Executive Officer (Principal 
David W. Barry               Executive Officer)
                   

/s/ James A. Klein, Jr.      Chief Financial Officer           October 31, 1996
-------------------------    and Treasurer
James A. Klein, Jr.          (Principal Financial
                             and Accounting Officer)

                                         II-5

<PAGE>


/s/ M. Nixon Ellis           Director, President and           October 31, 1996
-------------------------    Chief Operating Officer
M. Nixon Ellis  


/s/ Anthony B. Evnin         Director                          October 31, 1996
-------------------------
Anthony B. Evnin


/s/ Standish M. Fleming      Director                          October 31, 1996
-------------------------
Standish M. Fleming


/s/ Karl Y. Hostetler        Director                          October 31, 1996
-------------------------
Karl Y. Hostetler


/s/ George McFadden          Director                          October 31, 1996
-------------------------
George McFadden


/s/ Peter McPartland         Director                          October 31, 1996
-------------------------
Peter McPartland

                                         II-6

<PAGE>

                          SECURITIES AND EXCHANGE COMMISSION

                                   WASHINGTON, D.C.



                                       EXHIBITS

                                          TO

                                       FORM S-8

                                        UNDER

                                SECURITIES ACT OF 1933


                            TRIANGLE PHARMACEUTICALS, INC.



<PAGE>
                                    EXHIBIT INDEX


Exhibit
Number   Exhibit
-------  -------

 *4.1    Second Restated Certificate of Incorporation of the Company 
         (Exhibit 3.2).
 *4.2    Restated Bylaws of the Company (Exhibit 3.4).
 +4.3    Form of Certificate for Common Stock (Exhibit 4.1).
  5.1    Opinion and consent of Brobeck, Phleger & Harrison LLP.
 23.1    Consent of Brobeck, Phleger & Harrison LLP (contained in Exhibit 5.1).
 23.2    Consent of Independent Accountants, Price Waterhouse LLP.
*99.1    1996 Stock Incentive Plan (Exhibit 10.35).
*99.2    1996 Stock Incentive Plan Form of Notice of Grant (Exhibit 10.36).
*99.3    1996 Stock Incentive Plan Form of Stock Option Agreement (Exhibit 
         10.37).
*99.4    Employee Stock Purchase Plan (Exhibit 10.38).

--------------------

*   These exhibits were previously filed as part of, and are hereby
    incorporated by reference to, the same numbered exhibit (except as
    otherwise noted) filed with the Company's Registration Statement on Form 
    S-1 (Commission No. 333-11793) filed on September 11, 1996.

+   These exhibits were previously filed as part of, and are hereby 
    incorporated by reference to, the same numbered exhibit (except as 
    otherwise noted) filed with the Company's Amendment No. 2 to Registration 
    Statement on Form S-1 (Commission No. 333-11793) filed on October 23, 1996.
[{"type": "S-8", "sequence": "1", "description": "S-8", "secsgml_size_bytes": 21879}]
{"company-data": {"conformed-name": "TRIANGLE PHARMACEUTICALS INC", "cik": "0001022622", "assigned-sic": "2834", "irs-number": "561930728", "state-of-incorporation": "DE", "fiscal-year-end": "1231"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-15187", "film-number": "96651140"}, "business-address": {"street1": "4 UNIVERSITY PLACE", "street2": "4611 UNIVERSITY DRIVE", "city": "DURHAM", "state": "NC", "zip": "27707", "phone": "9194935980"}, "mail-address": {"street1": "4 UNIVERSITY PLACE", "street2": "4611 UNIVERSITY DRIVE", "city": "DURHAM", "state": "NC", "zip": "27707"}}
AS FILED WITH THE SECURITIES AND EXCHANGE COMMISSION ON October 31, 1996
                                          REGISTRATION NO. 333-___________

--------------------------------------------------------------------------------
--------------------------------------------------------------------------------

                          SECURITIES AND EXCHANGE COMMISSION
                                WASHINGTON, D.C. 20549

                                ---------------------

                                       FORM S-8
                                REGISTRATION STATEMENT
                                        UNDER
                              THE SECURITIES ACT OF 1933

                            TRIANGLE PHARMACEUTICALS, INC.
                  (Exact name of issuer as specified in its charter)

             DELAWARE                                    56-1930728             
(State or other jurisdiction of             (I.R.S. Employer Identification No.)
incorporation or organization)

                      4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE
                             DURHAM, NORTH CAROLINA 27707
                  (Address of Principal Executive Office) (Zip Code)
                                ----------------------
                              1996 STOCK INCENTIVE PLAN
                             EMPLOYEE STOCK PURCHASE PLAN
                              (Full title of the plans)
                                ----------------------
                                  DR. DAVID W. BARRY
                         Chairman and Chief Executive Officer
                            TRIANGLE PHARMACEUTICALS, INC.
                      4 UNIVERSITY PLACE, 4611 UNIVERSITY DRIVE
                     DURHAM, NORTH CAROLINA 27707  (919) 493-5980
(Name, address and telephone number, including area code, of agent for service)
                                ----------------------
                                      Copies to:
                               John A. Denniston, Esq.
                                  John R. Cook, Esq.
                           BROBECK, PHLEGER & HARRISON LLP
                            550 West C Street, Suite 1300
                             San Diego, California  92101
                                    (619) 234-1966
                                ----------------------
            This Registration Statement shall become effective immediately
               upon filing with the Securities and Exchange Commission
              and sales of the registered securities will begin as soon
                 as reasonably practicable after such effective date.
                                ---------------------

                           CALCULATION OF REGISTRATION FEE
------------------------------------------------------------------------------------------
                                            Proposed       Proposed                    
                                             maximum       maximum                     
Title of                                     offering     aggregate          Amount of 
securities to           Amount to be          price        offering        registration
be registered            registered         per share       price               fee    
------------------------------------------------------------------------------------------
Common Stock, $0.001    1,882,667(1)         $9.50(2)   $17,885,337(2)           $5,420
par value per share                                                                    
(under 1996                                                                            
Stock Incentive Plan)                                                                  

Common Stock, $0.001      300,000(1)         $9.50(2)    $2,850,000(2)             $864
par values per share                                                                   
(under Employee                                                                   
Stock Purchase Plan)
--------------------
(1)  This Registration Statement shall also cover any additional shares of
Common Stock which become issuable under the 1996 Stock Incentive Plan and
the Employee Stock Purchase Plan by reason of any stock dividend, stock split,
recapitalization or other similar transaction effected without  the receipt of
consideration which results in an increase in the number of the Company's
outstanding shares of Common Stock.
(2)  Estimated solely for the purposes of computing the amount of registration
fee in accordance with Rule 457(c) under the Securities Act of 1933, as amended.
PART II

                  INFORMATION REQUIRED IN THE REGISTRATION STATEMENT

Item 3.  INCORPORATION OF DOCUMENTS BY REFERENCE.
    
    Triangle Pharmaceuticals, Inc. (the "Registrant" or "Company") hereby
incorporates by reference into this Registration Statement the following
document previously filed with the Securities and Exchange Commission (the
"Commission"):

    (a)  the Registrant's Prospectus filed September 11, 1996 with the
    Registrant's Registration Statement No. 333-11793 on Form S-1, as amended,
    under the Securities Act of 1933, as amended (the "Securities Act"), in
    which there is set forth the Registrant's audited financial statements for
    the period from the Registrant's inception (July 12, 1995) to December 31,
    1995.

    (b)  the Registrant's Registration Statement on Form 8-A filed October 18,
    1996, with the Commission pursuant to Section 12 of the Securities Exchange
    Act of 1934, as amended (the "Exchange Act"), in which there is described
    the terms, rights and provisions applicable to the Registrant's outstanding
    Common Stock. 

    All documents filed by Registrant pursuant to Section 13(a), 13(c), 14 or
15(d) of the Exchange Act after the date of this Registration Statement and
prior to the filing of a post-effective amendment which indicates that all
securities offered hereby have been sold or which deregisters all securities
then remaining unsold, shall be deemed to be incorporated by reference into this
Registration Statement and to be a part hereof from the date of filing of such
documents.

Item 4.  DESCRIPTION OF SECURITIES

         Not applicable.

Item 5.  INTERESTS OF NAMED EXPERTS AND COUNSEL

    The validity of the Common Stock offered hereby will be passed upon for the
Company by Brobeck, Phleger & Harrison LLP, San Diego, California.  A member of
such firm owns a total of 13,333 shares of the Company's Common Stock.

Item 6.  INDEMNIFICATION OF DIRECTORS AND OFFICERS

    Section 145 of the Delaware General Corporation Law permits indemnification
of officers and directors of the Company under certain conditions and subject to
certain limitations.  Section 145 of the Delaware General Corporation Law also
provides that a corporation has the power to purchase and maintain insurance on
behalf of its officers and directors against any liability asserted against such
person and incurred by him or her in such capacity, or arising out of his or her
status as such, whether or not the corporation would have the power to indemnify
him or her against such liability under the provisions of Section 145 of the
Delaware General Corporation Law.

    Article VII, Section (i) of the Restated Bylaws of the Company provides
that the Company shall indemnify its directors and executive officers to the
fullest extent not prohibited by the Delaware General Corporation Law. The
rights to indemnity thereunder continue as to a person who has ceased to be a
director, officer, employee or agent and inure to the benefit of the heirs,
executors and administrators of the person.  In addition, expenses incurred by a
director or officer in defending any civil, criminal, administrative

                                         II-1
or investigative action, suit or proceeding by reason of the fact that he or
she is or was a director or officer of the Company (or was serving at the
Company's request as a director or officer of another corporation), shall be
paid by the Company in advance of the final disposition of such action, suit or
proceeding upon receipt of an undertaking by or on behalf of such director or
officer to repay such amount if it shall ultimately be determined that he or she
is not entitled to be indemnified by the Company as authorized by the relevant
section of the Delaware General Corporation Law.

    As permitted by Section 102(b)(7) of the Delaware General Corporation Law,
Article 5, Section (a) of the Company's Second Restated Certificate of
Incorporation provides that a director of the Company shall not be personally
liable for monetary damages for breach of fiduciary duty as a director, except
for liability (i) for any breach of the director's duty of loyalty to the
Company or its stockholders, (ii) for acts or omissions not in good faith or
acts or omissions that involve intentional misconduct or a knowing violation of
law, (iii) under Section 174 of the Delaware General Corporation Law or (iv) for
any transaction from which the director derived any improper personal benefit.

    The Company has entered into indemnification agreements with each of its
officers and directors.  Generally, the indemnification agreements attempt to
provide the maximum protection permitted by Delaware law as it may be amended
from time to time.  Under such additional indemnification provisions, however,
an individual will not receive indemnification for judgments, settlements or
expenses if he or she is found liable to the Company (except to the extent the
court determines he or she is fairly and reasonably entitled to indemnity for
expenses), for settlements not approved by the Company or for settlement and
expenses if the settlement is not approved by the court.  The indemnification
agreements provide for the Company to advance to the individual any and all
reasonable expenses (including legal fees and expenses) incurred in
investigating or defending any such action, suit or proceeding.  In order to
receive an advance of expenses, the individual must submit to the Company copies
of invoices presented to him or her for such expenses.  Also, the individual
must repay such advances upon a final judicial decision that he or she is not
entitled to indemnification.

    The Company has also purchased directors' and officers' liability 
insurance.

Item 7.  EXEMPTION FROM REGISTRATION CLAIMED

         Not Applicable.

                                         II-2
Item 8.  EXHIBITS

Exhibit Number        Exhibit
--------------        -------

     *4.1        Second Restated Certificate of Incorporation of the Company   
                 (Exhibit 3.2).
     *4.2        Restated Bylaws of the Company (Exhibit 3.4).
     +4.3        Form of Certificate for Common Stock (Exhibit 4.1).
      5.1        Opinion and consent of Brobeck, Phleger & Harrison LLP.
     23.1        Consent of Brobeck, Phleger & Harrison LLP (contained in 
                 Exhibit 5.1).
     23.2        Consent of Independent Accountants, Price Waterhouse LLP.
    *99.1        1996 Stock Incentive Plan (Exhibit 10.35).
    *99.2        1996 Stock Incentive Plan Form of Notice of Grant (Exhibit 
                 10.36).
    *99.3        1996 Stock Incentive Plan Form of Stock Option Agreement 
                 (Exhibit  10.37).
    *99.4        Employee Stock Purchase Plan (Exhibit 10.38).

-------------------

*   These exhibits were previously filed as part of, and are hereby
    incorporated by reference to, the same numbered exhibit (except as
    otherwise noted) filed with the Company's Registration Statement on Form 
    S-1 (Commission No. 333-11793) filed on September 11, 1996.

+   These exhibits were previously filed as part of, and are hereby 
    incorporated by reference to, the same numbered exhibit (except as 
    otherwise noted) filed with the Company's Amendment No. 2 to Registration 
    Statement on Form S-1 (Commission No. 333-11793) filed on October 23, 1996.

Item 9.  UNDERTAKINGS

         A.  The undersigned Registrant hereby undertakes:  (1) to file, during
any period in which offers or sales are being made, a post-effective amendment
to this Registration Statement (i) to include any prospectus required by
Section 10(a)(3) of the Securities Act of 1933, (ii) to reflect in the
prospectus any facts or events arising after the effective date of this
Registration Statement (or the most recent post-effective amendment thereof)
which, individually or in the aggregate, represent a fundamental change in the
information set forth in this Registration Statement, and (iii) to include any
material information with respect to the plan of distribution not previously
disclosed in this Registration Statement or any material change to such
information in this Registration Statement; PROVIDED, HOWEVER, that
clauses (1)(i) and (1)(ii) shall not apply if the information required to be
included in a post-effective amendment by those clauses is contained in periodic
reports filed by the Registrant pursuant to Section 13 or Section 15(d) of the
Securities Exchange Act of 1934 that are incorporated by reference into this
Registration Statement; (2) that for the purpose of determining any liability
under the Securities Act of 1933, each such post-effective amendment shall be
deemed to be a new registration statement relating to the securities offered
therein and the offering of such securities at that time shall be deemed to be
the initial BONA FIDE offering thereof; and (3) to remove from registration by
means of a post-effective amendment any of the securities being registered which
remain unsold upon the termination of the offering.

         B.  The undersigned registrant hereby undertakes that, for purposes of
determining any liability under the Securities Act of 1933, each filing of the
registrant's annual report pursuant to Section 13(a) or 15(d) of the Securities
Exchange Act of 1934 (and, where applicable, each filing of an employee benefit
plan's annual report pursuant to Section 15(d) of the Securities Exchange Act of
1934) that is incorporated by reference in the registration statement shall be
deemed to be a new registration statement relating to the securities offered
therein, and the offering of such securities at that time shall be deemed to be
the initial BONA FIDE offering thereof.

         C.  Insofar as indemnification for liabilities arising under the
Securities Act of 1933 may be permitted to directors, officers or controlling
persons of the Registrant pursuant to the indemnity provisions incorporated by
reference in Item 6, or otherwise, the Registrant has been informed that in the
opinion of

                                         II-3
the Securities and Exchange Commission such indemnification is against public
policy as expressed in the 1933 Act and is, therefore, unenforceable.  In the
event that a claim for indemnification against such liabilities (other than the
payment by the Registrant of expenses incurred or paid by a director, officer or
controlling person of the Registrant in the successful defense of any action,
suit or proceeding) is asserted by such director, officer or controlling person
in connection with the securities being registered, the Registrant will, unless
in the opinion of its counsel the matter has been settled by controlling
precedent, submit to a court of appropriate jurisdiction the question whether
such indemnification by it is against public policy as expressed in the 1933 Act
and will be governed by the final adjudication of such issue.
 
                                         II-4
SIGNATURES

         Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets all
of the requirements for filing on Form S-8, and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Durham, State of North Carolina, on this 
31st day of October, 1996.

                                       TRIANGLE PHARMACEUTICALS, INC.

                                       By  /s/ David W. Barry
                                          ------------------------------------
                                          DAVID W. BARRY
                                          Chairman and Chief Executive Officer 

                                  POWER OF ATTORNEY

KNOW ALL PERSONS BY THESE PRESENTS:

         That the undersigned officers and directors of Triangle
Pharmaceuticals, Inc. a Delaware corporation, do hereby constitute and appoint
David W. Barry and James A. Klein, Jr., and each of them, the lawful attorneys-
in-fact and agents with full power and authority to do any and all acts and
things and to execute any and all instruments which said attorneys and agents,
and either one of them, determine may be necessary or advisable or required to
enable said corporation to comply with the Securities Act of 1933, as amended,
and any rules or regulations or requirements of the Securities and Exchange
Commission in connection with this Registration Statement.  Without limiting the
generality of the foregoing power and authority, the powers granted include the
power and authority to sign the names of the undersigned officers and directors
in the capacities indicated below to this Registration Statement, to any and all
amendments, both pre-effective and post-effective, and supplements to this
Registration Statement, and to any and all instruments or documents filed as
part of or in conjunction with this Registration Statement or amendments or
supplements thereof, and each of the undersigned hereby ratifies and confirms
that all said attorneys and agents, or either of them, shall do or cause to be
done by virtue hereof.  This Power of Attorney may be signed in several
counterparts.

         IN WITNESS WHEREOF, each of the undersigned has executed this Power of
Attorney as of the date indicated.

         Pursuant to the requirements of the Securities Act of 1933, this
Registration Statement has been signed below by the following persons in the
capacities and on the dates indicated.

Signature                    Title                              Date
---------                    -----                              ----

/s/ David W. Barry           Chairman of the Board and Chief   October 31, 1996
-------------------------    Executive Officer (Principal 
David W. Barry               Executive Officer)
                   

/s/ James A. Klein, Jr.      Chief Financial Officer           October 31, 1996
-------------------------    and Treasurer
James A. Klein, Jr.          (Principal Financial
                             and Accounting Officer)

                                         II-5
/s/ M. Nixon Ellis           Director, President and           October 31, 1996
-------------------------    Chief Operating Officer
M. Nixon Ellis  

/s/ Anthony B. Evnin         Director                          October 31, 1996
-------------------------
Anthony B. Evnin

/s/ Standish M. Fleming      Director                          October 31, 1996
-------------------------
Standish M. Fleming

/s/ Karl Y. Hostetler        Director                          October 31, 1996
-------------------------
Karl Y. Hostetler

/s/ George McFadden          Director                          October 31, 1996
-------------------------
George McFadden

/s/ Peter McPartland         Director                          October 31, 1996
-------------------------
Peter McPartland

                                         II-6
SECURITIES AND EXCHANGE COMMISSION

                                   WASHINGTON, D.C.

                                       EXHIBITS

                                          TO

                                       FORM S-8

                                        UNDER

                                SECURITIES ACT OF 1933

                            TRIANGLE PHARMACEUTICALS, INC.
EXHIBIT INDEX

Exhibit
Number   Exhibit
-------  -------

 *4.1    Second Restated Certificate of Incorporation of the Company 
         (Exhibit 3.2).
 *4.2    Restated Bylaws of the Company (Exhibit 3.4).
 +4.3    Form of Certificate for Common Stock (Exhibit 4.1).
  5.1    Opinion and consent of Brobeck, Phleger & Harrison LLP.
 23.1    Consent of Brobeck, Phleger & Harrison LLP (contained in Exhibit 5.1).
 23.2    Consent of Independent Accountants, Price Waterhouse LLP.
*99.1    1996 Stock Incentive Plan (Exhibit 10.35).
*99.2    1996 Stock Incentive Plan Form of Notice of Grant (Exhibit 10.36).
*99.3    1996 Stock Incentive Plan Form of Stock Option Agreement (Exhibit 
         10.37).
*99.4    Employee Stock Purchase Plan (Exhibit 10.38).

--------------------

*   These exhibits were previously filed as part of, and are hereby
    incorporated by reference to, the same numbered exhibit (except as
    otherwise noted) filed with the Company's Registration Statement on Form 
    S-1 (Commission No. 333-11793) filed on September 11, 1996.

+   These exhibits were previously filed as part of, and are hereby 
    incorporated by reference to, the same numbered exhibit (except as 
    otherwise noted) filed with the Company's Amendment No. 2 to Registration 
    Statement on Form S-1 (Commission No. 333-11793) filed on October 23, 1996.