SEC FORM 4

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

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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^*

HEN STEWART

(Last)

(First)

(Middle)

WARBURG PINCUS PRIVATE EQUITY VIII, L.P.

466 LEXINGTON AVENUE

(Street)

NEW YORK

10017

(City)

(State)

(Zip)

2. Issuer Name and Ticker or Trading Symbol
Altus Pharmaceuticals Inc. [ ALTU ]

5. Relationship of Reporting Person(s) to Issuer
(Check all applicable)

X	Director	X	10% Owner
	Officer (give title below)		Other (specify below)

3. Date of Earliest Transaction (Month/Day/Year)
01/31/2006

4. If Amendment, Date of Original Filed (Month/Day/Year)

6. Individual or Joint/Group Filing (Check Applicable Line)

X	Form filed by One Reporting Person
	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)
1. Title of Security (Instr. 3)	2. Transaction Date (Month/Day/Year)	2A. Deemed Execution Date, if any (Month/Day/Year)	Code	V	Amount	(A) or (D)	Price		6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	7. Nature of Indirect Beneficial Ownership (Instr. 4)
Common Stock	01/31/2006⁽¹⁾		C		3,589,246⁽²⁾⁽³⁾	A	⁽³⁾	3,589,246⁽²⁾⁽³⁾	I	Shares held by Warburg Pincus Private Equity VIII, L.P.⁽⁴⁾

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)
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)	Code	V	(A)	(D)	Date Exercisable	Expiration Date	Title	Amount or Number of Shares	8. Price of Derivative Security (Instr. 5)		10. Ownership Form: Direct (D) or Indirect (I) (Instr. 4)	11. Nature of Indirect Beneficial Ownership (Instr. 4)
Series C Convertible Preferred Stock	⁽³⁾	01/31/2006⁽¹⁾		C			3,589,246⁽²⁾⁽³⁾	05/21/2004	01/31/2006⁽¹⁾	Common Stock	3,589,246⁽²⁾⁽³⁾	$0.00	0	I	Shares held by Warburg Pincus Private Equity VIII, L.P.⁽⁴⁾
Warrant	$9.802	01/31/2006⁽¹⁾		C		717,917⁽⁵⁾		05/21/2004	05/21/2011	Common Stock	717,917⁽⁵⁾	$9.802	717,917⁽⁵⁾	I	Shares held by Warburg Pincus Private Equity VIII, L.P.⁽⁴⁾

Explanation of Responses:

1. This is the date of the closing of the Issuer's initial public offering.

2. Includes dividends that had been accruing on the Series C Convertible Preferred Stock and which were paid out in 325,995 shares of common stock as of the date of the closing of the Issuer's intial public offering.

3. All outstanding shares of the Issuer's Series C Convertible Preferred Stock converted to common stock at a rate of .4401933369 - to- 1 upon the completion of the Issuer's initial public offering.

4. The stockholder is Warburg Pincus Private Equity VIII, L.P. ("WP VIII"). Warburg Pincus Partners, LLC ("WPP LLC"), a subsidiary of Warburg Pincus & Co. ("WP"), is the sole general partner of WP VIII. WP VIII is managed by Warburg Pincus LLC ("WP LLC"). Mr. Hen is a general partner of WP and managing director and member of WP LLC. All shares indicated as owned by Mr. Hen are included because of his affiliation with the Warburg Pincus entities. Mr. Hen disclaims beneficial ownership of all shares held by the Warburg Pincus entities.

5. Warrants were automatically adjusted on a basis of .4401933369 - to- 1 upon closing of the Issuer's public offering. The number of adjusted warrants reported are exercisable for common stock on a 1 for 1 basis.

Remarks:

	/s/ Marianne Staniunas, Attorney in Fact	02/01/2006
	** 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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