OTSKF / Otsuka Holdings Co., Ltd. - Pengajuan SECLaporan Tahunan, Pernyataan Proksi

Otsuka Pharmaceutical Completes Acquisition of Avanir Pharmaceuticals

EX-99.A.5.G Exhibit (a)(5)(G) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Yuji Kogure Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Pharmaceutical Completes Acquisition of Avanir Pharmaceuticals Tokyo, Japan –

OTSKY / Otsuka Holdings Co. Ltd. SC TO-T/A - - SC TO-T/A

SC TO-T/A 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) AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary

CREDIT AGREEMENT

EX-99.B.2 Exhibit (b)(2) CREDIT AGREEMENT This CREDIT AGREEMENT (this “Agreement”) is dated as of January 6, 2015, and is by and between OTSUKA AMERICA, INC. (the “Borrower”), a corporation duly organized and validly existing under the laws of the State of Delaware, and THE BANK OF TOKYO-MITSUBISHI UFJ, LTD., a Japanese banking corporation (the “Bank”). The Borrower desires the Bank to lend certai

OTSKY / Otsuka Holdings Co. Ltd. SC TO-T/A - - SC TO-T/A

SC TO-T/A 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. 3) AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary

Otsuka Holdings Announces Expiration of HSR Waiting Period for Avanir Tender Offer

EX-(a)(5)(F) Exhibit (a)(5)(F) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co.

OTSKY / Otsuka Holdings Co. Ltd. SC TO-T/A - - SC TO-T/A

SC TO-T/A 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. 2) AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary

OTSKY / Otsuka Holdings Co. Ltd. SC TO-T/A - - SC TO-T/A

SC TO-T/A 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. 1) AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary

OTSKY / Otsuka Holdings Co. Ltd. SC TO-T - - SC TO-T

SC TO-T 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 AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary of Otsuka Pharmaceut

Offer to Purchase for Cash All Outstanding Shares of Common Stock AVANIR PHARMACEUTICALS, INC. $17.00 NET PER SHARE BIGARADE CORPORATION a wholly owned indirect subsidiary of OTSUKA PHARMACEUTICAL CO., LTD. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE

EX-99.A.1.A Exhibit (a)(1)(A) Offer to Purchase for Cash All Outstanding Shares of Common Stock of AVANIR PHARMACEUTICALS, INC. at $17.00 NET PER SHARE by BIGARADE CORPORATION a wholly owned indirect subsidiary of OTSUKA PHARMACEUTICAL CO., LTD. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGHT, NEW YORK CITY TIME, AT THE END OF JANUARY 12, 2015, UNLESS THE OFFER IS EXTENDED (SUCH DATE

EX-99.A.1.E

EX-99.A.1.E Exhibit (a)(1)(E) Letter to Clients with Respect to Offer to Purchase All Outstanding Shares of Common Stock of Avanir Pharmaceuticals, Inc. at $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 by Bigarade Corporation an indirect wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGH

Letter to Brokers and Dealers with Respect to Offer to Purchase All Outstanding Shares of Common Stock Avanir Pharmaceuticals, Inc. $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 Bigarade Corporation an indir

EX-99.A.1.D Exhibit (a)(1)(D) Letter to Brokers and Dealers with Respect to Offer to Purchase All Outstanding Shares of Common Stock of Avanir Pharmaceuticals, Inc. at $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 by Bigarade Corporation an indirect wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 1

MUTUAL NON-DISCLOSURE AGREEMENT

EX-99.D.2 Exhibit (d)(2) MUTUAL NON-DISCLOSURE AGREEMENT MUTUAL NON-DISCLOSURE AGREEMENT THIS MUTUAL NON-DISCLOSURE AGREEMENT (this “Agreement”), entered into as of MAY 13, 2013 (the “Effective Date”), governs the disclosure of information by and between AVANIR PHARMACEUTICALS, INC., a Delaware corporation, with offices located at 20 Enterprise, Suite 200, Aliso Viejo, California, 92656, and OTSUK

Commitment Letter concerning USD3,540,000,000 Credit Facility

EX-99.B.1 Exhibit (b)(1) December 9, 2014 Otsuka Holdings Co., Ltd. 2-9 Kanda-Tsukasamachi, Chiyoda-ku, Tokyo 101-0048 Attn: Mr. Atsumasa Makise Otsuka America, Inc. One Embarcadero Center, Suite 2020, San Francisco, CA 94111, U.S.A. Attn: Ms. Noriko Tojo Dear Sirs, Commitment Letter concerning USD3,540,000,000 Credit Facility We (“us” or the “Bank”) refer to the contemplated debt financing reques

FIRST AMENDMENT NON-DISCLOSURE AGREEMENT

EX-99.D.3 Exhibit (d)(3) FIRST AMENDMENT TO NON-DISCLOSURE AGREEMENT THIS FIRST AMENDMENT to the Non-Disclosure Agreement (“Amendment”) is effective as of JULY 16, 2013, by and between AVANIR PHARMACEUTICALS, INC. (“Avanir”) and OTSUKA PHARMACEUTICAL CO. LTD. (“Company”). Hereafter, each of Avanir and Company may also be referred to as a “party” and sometimes collectively referred to as the “parti

Notice of Guaranteed Delivery Offer to Purchase All Outstanding Shares of Common Stock Avanir Pharmaceuticals, Inc. $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 Bigarade Corporation an indirect wholly owned

EX-99.A.1.C Exhibit (a)(1)(C) Notice of Guaranteed Delivery for Offer to Purchase All Outstanding Shares of Common Stock of Avanir Pharmaceuticals, Inc. at $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 by Bigarade Corporation an indirect wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT 12:00 MIDNIGH

Request for Taxpayer Identification Number and Certification

EX-99.A.1.F Exhibit (a)(1)(F) Form W-9 (Rev. August 2013) Department of the Treasury Internal Revenue Service Request for Taxpayer Identification Number and Certification Give Form to the requester. Do not send to the IRS. Name (as shown on your income tax return) Business name/disregarded entity name, if different from above Check appropriate box for federal tax classification: Exemptions (see in

SECOND AMENDMENT NON-DISCLOSURE AGREEMENT

EX-99.D.4 Exhibit (d)(4) EXECUTION VERSION SECOND AMENDMENT TO NON-DISCLOSURE AGREEMENT THIS SECOND AMENDMENT to the Non-Disclosure Agreement (“Amendment”) is effective as of SEPTEMBER 2, 2014, by and between AVANIR PHARMACEUTICALS, INC. (“Avanir”) and OTSUKA PHARMACEUTICAL CO. LTD. (“Company”). Hereafter, each of Avanir and Company may also be referred to as a “party” and sometimes collectively r

THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION Letter of Transmittal To Tender Shares of Common Stock Avanir Pharmaceuticals, Inc. $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 Bigarade Cor

EX-99.A.1.B Exhibit (a)(1)(B) THIS DOCUMENT IS IMPORTANT AND REQUIRES YOUR IMMEDIATE ATTENTION Letter of Transmittal To Tender Shares of Common Stock of Avanir Pharmaceuticals, Inc. at $17.00 Per Share, Net in Cash, Pursuant to the Offer to Purchase dated December 12, 2014 by Bigarade Corporation an indirect wholly owned subsidiary of Otsuka Pharmaceutical Co., Ltd. THE OFFER AND WITHDRAWAL RIGHTS

Notice of Offer to Purchase for Cash All Outstanding Shares of Common Stock AVANIR PHARMACEUTICALS, INC. $17.00 NET PER SHARE BIGARADE CORPORATION a wholly owned indirect subsidiary OTSUKA PHARMACEUTICAL CO., LTD.

EX-99.A.1.G Exhibit (a)(1)(G) This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below). The Offer (as defined below) is made only by the Offer to Purchase, dated December 12, 2014, and the related Letter of Transmittal and any amendments or supplements thereto, and is being made to all holders of Shares. The Offer is not being made to (nor

Otsuka Pharmaceutical Commences Tender Offer to Acquire All Outstanding Shares of Avanir Pharmaceuticals

EX-99.A.5.E Exhibit (a)(5)(E) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Yuji Kogure Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Pharmaceutical Commences Tender Offer to Acquire All Outstanding Shares of Ava

xCover sheet

EX-99.A.5.D Exhibit (a)(5)(D) xCover sheet Document title: Extraordinary Report Filing to: Director-General of the Kanto Local Finance Bureau Filing date: December 10, 2014 Company name: Otsuka Holdings Co., Ltd. Title and name of representative: Tatsuo Higuchi President and Representative Director, CEO Registered address: 2-9, Kanda Tsukasa-machi, Chiyoda-ku, Tokyo 101-8535, Japan Telephone numbe

OTSKY / Otsuka Holdings Co. Ltd. SC TO-C - - SC TO-C

SC TO-C 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 AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary of Otsuka Pharmaceut

English Translation of Press Release of Otsuka Holdings Co., Ltd. filed with the Tokyo Stock Exchange and dated December 2, 2014

AVANIR PHARMACEUTICALS, INC. SC TO-C Exhibit (a)(5)(A) December 2, 2014 Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Yuji Kogure Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Pharmaceutical to Acquire Avanir Pharmaceuticals Full-scal

Press Release of Otsuka Pharmaceutical Co., Ltd. dated December 2, 2014

AVANIR PHARMACEUTICALS, INC. SC TO-C Exhibit (a)(5)(B) OTSUKA PHARMACEUTICAL TO ACQUIRE AVANIR PHARMACEUTICALS Full-scale entry to neurologic diseases area widens core business presence in CNS Tokyo, Japan – December 2, 2014 – Otsuka Pharmaceutical Co., Ltd. is pleased to announce an agreement with Avanir Pharmaceuticals, Inc. (“Avanir”) in which Otsuka America, Inc., a US subsidiary, acquires Ava

OTSKY / Otsuka Holdings Co. Ltd. SC TO-C - - TENDER OFFER STATEMENT

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 AVANIR PHARMACEUTICALS, INC. (Name of Subject Company) Bigarade Corporation (Offeror) a wholly owned direct subsidiary of Otsuka America, Inc. (Direct Parent of Offeror) a wholly owned indirect subsidiary of Otsuka Pharmaceutical Co.

English Translation of Investor Presentation of Otsuka Holdings Co., Ltd. dated December 2, 2014

AVANIR PHARMACEUTICALS, INC. SC TO-C Exhibit (a)(5)(C) Acquisition of Avanir Pharmaceuticals Tatsuo Higuchi President & Representative Director, CEO Otsuka Holdings Co., Ltd. 2 Dec, 2014 1 Note to Investors The tender offer to purchase shares of Avanir common stock referenced in this presentation has not yet commenced, and this presentation is neither an offer to purchase, nor a solicitation of an

- SC TO-T/A

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 indirec

Otsuka Pharmaceutical Completes Acquisition of Astex Pharmaceuticals

Exhibit (a)(5)(B) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Takuma Kimura Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Pharmaceutical Completes Acquisition of Astex Pharmaceuticals Tokyo, Japan — October 11,

- SC TO-T/A

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. 3) 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 indirec

Otsuka Holdings Announces Expiration of HSR Waiting Period for Astex Tender Offer

Exhibit (a)(5)(A) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Takuma Kimura Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Holdings Announces Expiration of HSR Waiting Period for Astex Tender Offer Tokyo, Japan

- SC TO-T/A

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. 2) 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 o

- OTSUKA HOLDINGS CO., LTD. TENDER OFFER

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. 1) 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 o

Notice of Offer to Purchase for Cash All Outstanding Shares of Common Stock ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary of OTSUKA PHARMACEUTICAL CO., LTD.

Exhibit (a)(1)(F) This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below).

LETTER OF TRANSMITTAL To Tender Shares of Common Stock of ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE Pursuant to the Offer to Purchase dated September 13, 2013 by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary of OTSUKA PHA

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(B) LETTER OF TRANSMITTAL To Tender Shares of Common Stock of ASTEX PHARMACEUTICALS, INC.

Otsuka Pharmaceutical Commences Tender Offer to Acquire All Outstanding Shares of Astex Pharmaceuticals

Exhibit 99.(a)(1)(G) FOR IMMEDIATE RELEASE Company name: Otsuka Holdings Co., Ltd. Representative name: Tatsuo Higuchi President and Representative Director, CEO Stock ticker: 4578, Tokyo Stock Exchange, First Section Contact: Takuma Kimura Director, Investor Relations Department Telephone: +81-3-6361-7411 Otsuka Pharmaceutical Commences Tender Offer to Acquire All Outstanding Shares of Astex Phar

Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary of OTSUKA PHARMACEUTICAL CO., LTD.

Use these links to rapidly review the document TABLE OF CONTENTS Table of Contents Exhibit (a)(1)(A) Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC.

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Exhibit (d)(3) CONFIDENTIAL August 5, 2013 Otsuka Pharmaceutical Co., Ltd. Shinagawa Grand Central Tower 2-16-4 Konan, Minato-ku Tokyo 108-8242 Ladies and Gentlemen: Reference is made to that certain letter agreement between Otsuka Pharmaceutical Co., Ltd. and Astex Pharmaceuticals, Inc. dated July 3, 2013 (the “Original Agreement”). This letter agreement is to confirm our agreement with respect t

Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE Pursuant to the Offer to Purchase dated September 13, 2013 by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary of

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(D) Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC.

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Exhibit (d)(2) CONFIDENTIAL July 3, 2013 Otsuka Pharmaceutical Co., Ltd. Shinagawa Grand Central Tower 2-16-4 Konan, Minato-ku Tokyo 108-8242 Ladies and Gentlemen: In connection with the possible interest of Otsuka Pharmaceutical Co., Ltd. (“you” or “your”) in a negotiated transaction (a “Transaction”) involving Astex Pharmaceuticals, Inc. and its subsidiaries (collectively, the “Company”), the Co

AGREEMENT AND PLAN OF MERGER by and among OTSUKA PHARMACEUTICAL CO., LTD., AUTUMN ACQUISITION CORPORATION ASTEX PHARMACEUTICALS, INC. Dated as of September 5, 2013

Exhibit (d)(1) CONFIDENTIAL AGREEMENT AND PLAN OF MERGER by and among OTSUKA PHARMACEUTICAL CO.

NOTICE OF GUARANTEED DELIVERY For Tender of Shares of Common Stock of ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE Pursuant to the Offer to Purchase dated September 13, 2013 by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary o

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(C) NOTICE OF GUARANTEED DELIVERY For Tender of Shares of Common Stock of ASTEX PHARMACEUTICALS, INC.

Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC. at $8.50 NET PER SHARE Pursuant to the Offer to Purchase dated September 13, 2013 by AUTUMN ACQUISITION CORPORATION a wholly owned indirect subsidiary of

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(E) Offer to Purchase for Cash All Outstanding Shares of Common Stock of ASTEX PHARMACEUTICALS, INC.

- SC TO-T

QuickLinks - Click here to rapidly navigate through this document SECURITIES AND EXCHANGE COMMISSION Washington, D.