FORM 4

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

    Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP

Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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Filed By Romeo & Dye's Instant Form 4 Filer
www.section16.net

1. Name and Address of Reporting Person*

Amundsen, Jr. Robert F.

2. Issuer Name and Ticker or Trading Symbol
Triangle Pharmaceuticals, Inc. (VIRS)

6. Relationship of Reporting Person(s)
to Issuer (Check all applicable)
    Director                                       10% Owner
X Officer (give title below)          Other (specify below)

Executive VP & Chief Financial Officer        

(Last)      (First)     (Middle)

c/o Triangle Pharmaceuticals, Inc.
4611 University Drive, 4 University Place

3. I.R.S. Identification Number
of Reporting Person,
if an entity (voluntary)

(Street)

Durham, NC 27707

(City)     (State)     (Zip)

Table I — Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1. Title of Security
(Instr. 3)

2. Trans-
action
Date
(Month/ Day/
Year)

2A. Deemed
Execution
Date,
if any
(Month/Day/
Year)

3. Trans-
action Code
(Instr. 8)

4. Securities Acquired (A) or Disposed of (D)
(Instr. 3, 4 & 5)

5. Amount of
Securities
Beneficially
Owned Follow-
ing Reported Transactions(s)
(Instr. 3 & 4)

6. Owner-
ship Form:
Direct (D)
or Indirect (I)
(Instr. 4)

7. Nature of Indirect
Beneficial Ownership
(Instr. 4)

Code

V

Amount

(A)
or
(D)

Price

Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security

(Instr. 3)

2. Conver-
sion or
Exercise
Price of Derivative Security

3. Trans-
action Date

(Month/
Day/
Year)

4. Trans-
action
Code

(Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D)

(Instr. 3, 4 & 5)

6. Date Exercisable
and Expiration
Date
(Month/Day/
Year)

7. Title and Amount of Underlying Securities
(Instr. 3 & 4)

8. Price of Derivative Security
(Instr. 5)

9. Number of
Derivative
Securities
Beneficially
Owned
Following
Reported Transaction(s)
(Instr. 4)

10. Owner-
ship Form
of Deriv-
ative
Security:
Direct (D)
or Indirect (I)
(Instr. 4)

11. Nature of Indirect Beneficial Ownership
(Instr. 4)

Code

V

(A)

(D)

Date Exer-cisable

Expira-
tion
Date

Title

Amount or Number of
Shares

Stock Options (rights to buy)

$5.14

2/27/02

A

V

150,000

 ⁽¹⁾

2/26/12

Common Stock

150,000

Stock Options (rights to buy)

$2.92

8/5/02

A

V

100,000

 ⁽²⁾

8/4/12

Common Stock

100,000

Stock Options (rights to buy)

$2.92

9/20/02

A

150,000

 ⁽³⁾

8/4/12

Common Stock

150,000

555,000

D

Explanation of Responses:

(1) The options vest and become exercisable as follows: 25% become exercisable after the completion of one year of service measured from the date of grant and the remainder become exercisable in equal monthly installments for thirty-six months thereafter (the "Standard Vesting Schedule"); provided, however: (i) upon the filing (i.e., acceptance for review by the FDA) of an NDA (application for marketing approval in the US) for Coviracil® (emtricitabine) for the treatment of HIV on or before December 31, 2002, 25% of the Options shall automatically accelerate and become fully exercisable as of the date of the acceptance of the NDA for review by the FDA; and (ii) upon the approval of the NDA for Coviracil® (emtricitabine) for the treatment of HIV on or before December 31, 2003, an additional 25% of the Options shall automatically accelerate and become fully exercisable as of the date of marketing approval, if such options had not already become exercisable under the Standard Vesting Schedule.
(2) The options vest and become exercisable as follows: 25% on the first anniversary of the date of grant, and the remaining 75% thereafter in a series of 36 equal monthly installments.
(3) The options vest and become exercisable as follows: 25% on August 5, 2003, and the remaining 75% thereafter in a series of 36 equal monthly installments.

**Intentional misstatements or omissions of facts constitute Federal Criminal Violations.
See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).

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