ASTX Astex Pharmaceuticals, Inc. (MM)

UNITED STATES

SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE TO

TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR 13(e)(1) OF THE
SECURITIES EXCHANGE ACT OF 1934

(Amendment No. 4)

ASTEX PHARMACEUTICALS, INC.

(Name of Subject Company)

Autumn Acquisition Corporation

(Offeror)

a wholly owned direct subsidiary of

Otsuka America, Inc.
(Direct Parent of Offeror)
a wholly owned indirect subsidiary of

Otsuka Pharmaceutical Co., Ltd.
(Parent of Offeror)
a wholly owned subsidiary of

Otsuka Holdings Co., Ltd.
(Ultimate Parent of Offeror )

COMMON STOCK, $0.001 PAR VALUE PER SHARE
(Title of Class of Securities)

04624B10
(CUSIP Number of Class of Securities)

Hajime Seki
General Counsel and Director of Legal Affairs Department
Otsuka Holdings Co., Ltd.
Shinagawa Grand Central Tower
2-16-4 Konan, Minato-ku, Tokyo 108-8241, Japan
+81-3-6717-1400

(Name, Address and Telephone Number of Person Authorized to Receive Notices and Communications
on Behalf of Filing Persons)

CALCULATION OF FILING FEE

(1)                Estimated for purposes of calculating the filing fee only. The transaction valuation was calculated by multiplying the offer price of $8.50 per share of common stock of Astex Pharmaceuticals, Inc., par value $0.001 per share, (“Shares”) by 110,656,455 Shares, which is the sum of (i) 95,006,917 Shares issued and outstanding, (ii) 15,464,910 Shares issuable upon or otherwise deliverable in connection with the exercise of outstanding stock options to purchase Shares and (iii) 184,628 Shares issuable upon or otherwise deliverable in connection with the exercise of outstanding warrants.

(2)                The filing fee was calculated in accordance with Rule 0-11 under the Securities Exchange Act of 1934, as amended, and Fee Rate Advisory No. 1 for Fiscal Year 2013, issued August 31, 2012, by multiplying the transaction value by 0.00013640.

x                  Check the box if any part of the fee is offset as provided by Rule 0-11(a)(2) and identify the filing with which the offsetting fee was previously paid. Identify the previous filing by registration statement number, or the Form or Schedule and the date of its filing.

o                    Check the box if the filing relates solely to preliminary communications made before the commencement of a tender offer.

Check the appropriate boxes below to designate any transactions to which the statement relates:

x       Third-party offer subject to Rule 14d-1.

o       Issuer tender offer subject to Rule 13e-4.

o       Going-private transactions subject to Rule 13e-3.

o       Amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the results of the tender offer: x

This Amendment No. 4 (this “Amendment”) amends and supplements the Tender Offer Statement on Schedule TO filed with the Securities and Exchange Commission (“SEC”) on September 13, 2013 (which, together with Amendment No. 1, filed September 16, 2013, Amendment No. 2, filed on September 23, 2013, Amendment No. 3, filed on October 7, 2013, this Amendment and any subsequent amendments and supplements thereto, collectively constitute this “Schedule TO”) by Autumn Acquisition Corporation, a Delaware corporation (“Purchaser”) and a wholly owned indirect subsidiary of Otsuka Pharmaceutical Co., Ltd., a joint stock company organized under the laws of Japan (“Parent”). This Schedule TO relates to the tender offer by Purchaser to purchase all of the outstanding shares of common stock, par value $0.001 per share (the “Shares”), of Astex Pharmaceuticals, Inc., a Delaware corporation (“Astex”), at a purchase price of $8.50 per Share (the “Offer Price”), net to the seller in cash, without interest thereon and less any applicable withholding taxes payable in respect thereof, upon the terms and subject to the conditions set forth in (1) the Offer to Purchase, dated September 13, 2013 (as it may be amended or supplemented from time to time, the “Offer to Purchase”), which is set forth as Exhibit (a)(1)(A) hereto, and in the related Letter of Transmittal (as it may be amended or supplemented from time to time, the “Letter of Transmittal”), which is set forth as Exhibit (a)(1)(B) hereto (which offer, upon such terms and subject to such conditions, as it and they may be amended or supplemented from time to time, constitutes the “Offer”).

Capitalized terms used, but not otherwise defined, in this Amendment shall have the meanings ascribed to them in the Schedule TO.  The information in the Schedule TO is incorporated into this Amendment by reference to all applicable items in the Schedule TO, except that such information is hereby amended and supplemented to the extent specifically provided herein.

Items 1, 4, 8 and 11.

Items 1, 4, 8 and 11 of this Schedule TO are hereby amended and supplemented by the following:

“The Offer and withdrawal rights expired at 12:00 Midnight, New York City time, at the end of Thursday, October 10, 2013. The Depositary has advised that, as of the expiration time, 49,774,483 Shares were validly tendered and not withdrawn, representing approximately 52.3% of the total outstanding Shares. Therefore, the Minimum Condition has been satisfied. All Shares that were validly tendered and not validly withdrawn have been accepted for purchase by the Purchaser. Purchaser will promptly pay for such Shares at the Offer Price.

On October 11, 2013, Parent consummated the Merger pursuant to the terms of the Merger Agreement and in accordance with Section 251(h) of the DGCL.

On October 11, 2013, Otsuka Holdings Co., Ltd. issued a press release announcing the expiration and results of the Offer and the consummation of the Merger.

The full text of the press release issued by Otsuka Holdings Co., Ltd. on October 11, 2013 announcing the expiration and results of the Offer and the consummation of the Merger is filed as Exhibit (a)(5)(B) hereto and is incorporated herein by reference.

Item 12.  Exhibits

Item 12 of this Schedule TO is hereby amended and supplemented by adding the following exhibit:

(a)(5)(B) Press Release issued by Otsuka Holdings Co., Ltd. on October 11, 2013

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SIGNATURE

After due inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated: October 11, 2013

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*      Included in mailing to stockholders.

†      Previously filed.

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