Registration No. 333-42778

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

POST-EFFECTIVE AMENDMENT NO. 2
TO

FORM S-4

REGISTRATION STATEMENT
UNDER
THE SECURITIES ACT OF 1933

MILLENNIUM PHARMACEUTICALS, INC.

(Exact name of registrant as specified in its charter)

Delaware		8731		04-3177038
(State or other jurisdiction of incorporation or organization)		(Primary Standard Industrial Classification Code Number)		(I.R.S. Employer Identification Number)

40 Landsdowne Street

Cambridge, Massachusetts 02139

(617) 679-7000

(Address Including Zip Code, and Telephone Number,

Including Area Code, of Registrant’s Principal Executive Offices)

Joel S. Goldberg, Esq.		Copy to:
Vice President and Secretary		Matthew J. Gardella, Esq.
Millennium Pharmaceuticals, Inc.		Edwards Angell Palmer & Dodge LLP
40 Landsdowne Street		111 Huntington Avenue
Cambridge, Massachusetts 02139		Boston, Massachusetts 02199
Telephone: (617) 679-7000		Tel: (617) 239-0100
Telecopy: (617) 374-0074		Fax: (617) 227-4420

Telephone Number, Including Area Code, Of Agent For Service

Approximate date of commencement of proposed sale to the public:

Not Applicable. Deregistration of unsold securities

If the securities being registered on this Form are being offered in connection with the formation of a holding company and there is compliance with General Instruction G, check the following box. o

If this Form is filed to register additional securities for an offering pursuant to Rule 462(b) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. o

If this Form is a post-effective amendment filed pursuant to Rule 462(d) under the Securities Act, check the following box and list the Securities Act registration statement number of the earlier effective registration statement for the same offering. ¨

Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer, or a smaller reporting company. See the definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act. (Check one):

Large accelerated filer x		Accelerated filer o		Non accelerated filer o		Smaller reporting company o
				(Do not check if a smaller reporting company)

DEREGISTRATION OF SECURITIES

On August 1, 2000, Millennium Pharmaceuticals, Inc., a Delaware corporation (the “Company”) filed a registration statement on Form S-4, Registration No. 333-42778 (as subsequently amended by Post-Effective Amendment No. 1, filed October 2, 2000, this “Registration Statement”), with respect to 10,240,000 shares of the Company’s common stock, par value $0.001 per share, for issuance from time to time in acquisitions.

On May 14, 2008 (the “Effective Date”), the Company consummated the transactions contemplated by its Agreement and Plan of Merger (the “Merger Agreement”), dated as of April 10, 2008, by and among Takeda America Holdings, Inc., a New York corporation (“Parent”), Mahogany Acquisition Corp., a Delaware corporation and wholly owned subsidiary of Parent (“Merger Sub”), and the Company. Pursuant to the terms of the Merger Agreement, Merger Sub merged with and into the Company, with the Company continuing as the surviving corporation and a wholly owned subsidiary of Parent. In accordance with the Merger Agreement, the Company’s prior common stock, par value $0.001 per share (the “Common Stock”), has been canceled and is no longer outstanding. On May 14, 2008, the Company filed a certification and notice of termination on Form 15 with respect to the Company’s shares of Common Stock.

As a result of the consummation of the transactions contemplated by the Merger Agreement, the Company has terminated all offerings of the Company’s securities pursuant to this Registration Statement. Accordingly, pursuant to the undertakings contained in such Registration Statement to remove from registration, by means of a Post-Effective Amendment, any of the securities being registered which remain unsold at the termination of the offering, the Company is filing this Post-Effective Amendment to this Registration Statement to deregister any shares of the Company’s Common Stock registered and reserved for issuance under such Registration Statement which remained unissued as of the Effective Date.

SIGNATURES

Pursuant to the requirements of the Securities Act of 1933, the registrant has duly caused this Post-Effective Amendment No. 2 to the Registration Statement to be signed on its behalf by the undersigned, thereunto duly authorized, on this 6^th day of June, 2008.

	MILLENNIUM PHARMACEUTICALS, INC.


	By:	/s/ Joel S. Goldberg, Esq.
		Joel S. Goldberg, Esq., Vice President and Secretary

Pursuant to the requirements of the Securities Act of 1933, this Post-Effective Amendment No. 2 to the Registration Statement has been signed by the following persons in the capacities and on the date indicated.

Name	Title	Date

*	Director, President and Chief Executive Officer	June 6, 2008
Deborah Dunsire	(Principal Executive Officer)

*	Senior Vice President and Chief Financial Officer	June 6, 2008
Marsha H. Fanucci	(Principal Financial and Accounting Officer)

*	Director	June 6, 2008
Kiyoshi Kitazawa

*	Director	June 6, 2008
Masumitsu Inoue

The undersigned, by signing his name hereto, does hereby sign and execute this Post-Effective Amendment No. 2 to the Registration Statement on behalf of the above-named officers and directors of Millennium Pharmaceuticals, Inc. on this 6^th day of June, 2008, pursuant to the powers of attorney executed by such officers and directors, which powers of attorney are filed with the Securities and Exchange Commission as an exhibit to this Post-Effective Amendment No. 2 to the Registration Statement.

	*By:	/s/ Joel S. Goldberg, Esq.
		Joel S. Goldberg, Esq.
		Attorney-in-Fact

INDEX TO EXHIBITS

Exhibit Number		Description of Exhibit
24.1		Powers of Attorney