SEC Form 4

FORM 4		UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934 or Section 30(h) of the Investment Company Act of 1940	OMB APPROVAL OMB Number: 3235-0287 Estimated average burden hours per response: 0.5
	Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

1. Name and Address of Reporting Person* WARBURG PINCUS EQUITY PARTNERS LP (Last) (First) (Middle) 466 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip)	2. Issuer Name and Ticker or Trading Symbol SUNESIS PHARMACEUTICALS INC [ SNSS ]	5. Relationship of Reporting Person(s) to Issuer (Check all applicable) Director X 10% Owner Officer (give title below) Other (specify below)
	3. Date of Earliest Transaction (Month/Day/Year) 03/17/2006
	4. If Amendment, Date of Original Filed (Month/Day/Year)	6. Individual or Joint/Group Filing (Check Applicable Line) Form filed by One Reporting Person X Form filed by More than One Reporting Person

Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	3. Transaction Code (Instr. 8)		4. Securities Acquired (A) or Disposed Of (D) (Instr. 3, 4 and 5)			5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4)	6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
			Code	V	Amount	(A) or (D)	Price
Common Stock	03/17/2006		P		805,153	A	$6.21	3,626,875	D(1)(2)

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. Conversion or Exercise Price of Derivative Security	3. Transaction Date (Month/Day/Year)	3A. Deemed Execution Date, if any (Month/Day/Year)	4. Transaction Code (Instr. 8)		5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5)		6. Date Exercisable and Expiration Date (Month/Day/Year)		7. Title and Amount of Securities Underlying Derivative Security (Instr. 3 and 4)		8. Price of Derivative Security (Instr. 5)	9. Number of derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)	10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
				Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares
Common Stock Warrant	$6.21	03/17/2006		P		241,546		03/17/2006	03/17/2013	Common Stock	241,546	$0.125	241,546	D(1)

1. Name and Address of Reporting Person* WARBURG PINCUS EQUITY PARTNERS LP (Last) (First) (Middle) 466 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* WARBURG PINCUS & CO (Last) (First) (Middle) 466 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* WARBURG PINCUS LLC (Last) (First) (Middle) 466 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

1. Name and Address of Reporting Person* Warburg Pincus Partners LLC (Last) (First) (Middle) 466 LEXINGTON AVENUE (Street) NEW YORK NY 10017 (City) (State) (Zip) Relationship of Reporting Person(s) to Issuer Director X 10% Owner Officer (give title below) Other (specify below)

Explanation of Responses:

1. The shares of Common Stock and the Warrants are held by Warburg Pincus Equity Partners, L.P., a Delaware limited partnership, and two affiliated partnerships, together ("WPEP"). Warburg Pincus Partners LLC, a New York limited liability company ("WP Partners") and a direct subsidiary of Warburg Pincus & Co., a New York general partnership ("WP"), is the general partner of WPEP. WPEP is managed by Warburg Pincus LLC, a New York limited liability company ("WP LLC" and together with WP, WPEP and WP Partners, the "Warburg Entities").

2. WP Partners and WP LLC may be deemed to have an indirect pecuniary interest (within the meaning of Rule 16a-1 under the Securities Exchange Act of 1934) in an indeterminate portion of the shares owned by WPEP. WP Partners and WP LLC disclaim beneficial ownership of all shares held by WPEP. Charles R. Kaye and Joseph P. Landy are Managing General Partners of WP and Managing Members of WP LLC and may be deemed to control the Warburg Entities. Messrs. Kaye and Landy disclaim beneficial ownership of all shares held by the Warburg Entities. The address of the Warburg Entities is 466 Lexington Avenue, New York, New York 10017.

	Warburg, Pincus Equity Partners, L.P. By: Warburg Pincus Partners LLC, its General Partner, By: Warburg Pincus & Co., its Managing Member, By: /s/ Scott A. Arenare, Partner	03/20/2006
	** Signature of Reporting Person	Date
Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
* If the form is filed by more than one reporting person, see Instruction 4 (b)(v).
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