CBST / - SEC Filings, Annual Report, Proxy Statement

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CIK 912183
SEC Filings
All companies that sell securities in the United States must register with the Securities and Exchange Commission (SEC) and file reports on a regular basis. These reports include company annual reports (10K, 10Q), news updates (8K), investor presentations (found in 8Ks), insider trades (form 4), ownership reports (13D, and 13G), and reports related to the specific securities sold, such as registration statements and prospectus. This page shows recent SEC filings related to
SEC Filings (Chronological Order)
This page provides a complete, chronological list of SEC Filings, excluding ownership filings which we provide elsewhere.
February 17, 2015 SC 13G

CBST / / ARISTEIA CAPITAL LLC Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 Cubist Pharmaceuticals Inc. (Name of Issuer) Contractual Value Rights (Title of Class of Securities) 229678107 (CUSIP Number) 12/31/14 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which this Schedule is

February 10, 2015 SC 13G/A

CBST / / VANGUARD GROUP INC Passive Investment

cubistpharmaceuticalsinc.htm - Generated by SEC Publisher for SEC Filing SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 4 )* Name of issuer: Cubist Pharmaceuticals Inc Title of Class of Securities: Common Stock CUSIP Number: 229678107 Date of Event Which Requires Filing of this Statement: December 31, 2014 Check the

January 22, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - AMENDMENT NO. 10

Amendment No. 10 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. 10) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identify

January 21, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - AMENDMENT NO. 9

Amendment no. 9 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. 9) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifyin

January 21, 2015 EX-99.A.1.S

Merck Completes Tender Offer to Acquire Cubist

EX-99.A.1.S Exhibit (a)(1)(S) News Release FOR IMMEDIATE RELEASE Media Contacts: Lainie Keller (908) 236-5036 Investor Contacts: Joe Romanelli (908) 740-1986 Steve Cragle (908) 740-1801 Justin Holko (908) 740-1879 Merck Completes Tender Offer to Acquire Cubist KENILWORTH, N.J., January 21, 2015 – Merck (NYSE: MRK), known as MSD outside the United States and Canada, announced the successful complet

January 15, 2015 EX-99.(A)(1)(R)

THOMSON REUTERS STREETEVENTS

EX-99.(a)(1)(R) Exhibit (a)(1)(R) THOMSON REUTERS STREETEVENTS EDITED TRANSCRIPT MRK - Merck & Co Inc at JPMorgan Healthcare Conference EVENT DATE/TIME: JANUARY 13, 2015 / 12:00AM GMT THOMSON REUTERS STREETEVENTS | www.streetevents.com | Contact Us C2015 Thomson Reuters. All rights reserved. Republication or redistribution of Thomson Reuters content, including by framing or similar means, is prohi

January 15, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T AMENDMENT NO. 8

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. 8) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offe

January 14, 2015 SC 14D9/A

CBST / SC 14D9/A - - SC 14D9/A

SC 14D9/A 1 a15-23441sc14d9a.htm SC 14D9/A UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 4) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001

January 14, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T AMENDMENT NO. 7

SC TO-T AMENDMENT NO. 7 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. 7) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (id

January 13, 2015 EX-99.(A)(1)(Q)

Ken Frazier

EXHIBIT (A)(1)(Q) Exhibit (a)(1)(Q) Ken Frazier Chairman, Chief Executive Officer Merck & Co.

January 13, 2015 EX-99.1

Cubist Announces Withdrawal of Listing of CVRs (CBSTZ) from NASDAQ Global Select Market

Exhibit 99.1 FOR IMMEDIATE RELEASE Cubist Announces Withdrawal of Listing of CVRs (CBSTZ) from NASDAQ Global Select Market Lexington, Mass., January 13, 2015 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that it will voluntarily withdraw the contingent value rights (CVRs) it issued under a Contingent Value Rights Agreement dated October 24, 2013 (CVR Agreement) from listing on the

January 13, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T AMENDMENT NO. 6

SC TO-T Amendment No. 6 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. 6) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (id

January 13, 2015 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) January 13, 2015 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction of Incorporation) (Commissio

January 12, 2015 SC 13G/A

CBST / / Wellington Management Group LLP - SEC SCHEDULE 13G Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 8 )* Cubist Pharmaceuticals, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 229678107 (CUSIP Number) December 31, 2014 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to whic

January 12, 2015 EX-99.(A)(1)(G)

CUBIST PHARMACEUTICALS, INC. TENDER OFFER FREQUENTLY ASKED QUESTIONS

EX-99.(A)(1)(G) 2 a15-21731ex99da1g.htm EX-99.(A)(1)(G) Exhibit (a)(1)(G) CUBIST PHARMACEUTICALS, INC. TENDER OFFER FREQUENTLY ASKED QUESTIONS General 1. What does it mean to tender my shares? Merck has offered to acquire all of Cubist’s outstanding shares for $102.00 per share in cash through a tender offer. If you would like to accept this offer, you will “tender,” or deliver, your shares to Com

January 12, 2015 SC 14D9/A

CBST / SC 14D9/A - - SC 14D9/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 3) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 22

January 7, 2015 EX-99.(A)(1)(P)

NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC. 401(K) PLAN Date: January 6, 2015

(a)(1)(P) Exhibit (a)(1)(P) NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC.

January 7, 2015 EX-99.(A)(1)(O)

NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC. 401(K) PLAN Date: December 19, 2014 (revised January 6, 2015) The Tender Offer

EX-99.(A)(1)(O) 2 d848435dex99a1o.htm (A)(1)(O) Exhibit (a)(1)(O) NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC. 401(K) PLAN Date: December 19, 2014 (revised January 6, 2015) The Tender Offer As you may know, Mavec Corporation, a Delaware corporation (“Purchaser”), a wholly-owned subsidiary of Merck & Co., Inc., a New Jersey corporation (“Parent”) has offered to purchase each of the is

January 7, 2015 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - 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. 5) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offe

January 2, 2015 EX-99.1

NOTICE OF FAILURE PURCHASE TO THE HOLDERS OF THE Contingent Value Rights of Cubist Pharmaceuticals, Inc. (CUSIP No. 229678123)* Failure Purchase Date: February 2, 2015

Exhibit 99.1 NOTICE OF FAILURE PURCHASE TO THE HOLDERS OF THE Contingent Value Rights of Cubist Pharmaceuticals, Inc. (CUSIP No. 229678123)* Failure Purchase Date: February 2, 2015 NOTICE IS HEREBY GIVEN that, pursuant to the terms of the Contingent Value Rights Agreement by and between Cubist Pharmaceuticals, Inc. (the “Issuer”) and American Stock Transfer & Trust Company, LLC (the “Trustee”), da

January 2, 2015 8-K

Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) January 1, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

December 31, 2014 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T/A

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) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying stat

December 31, 2014 CORRESP

CBST / CORRESP - -

December 31, 2014 Via EDGAR Lisa M. Kohl Attorney-Adviser Nicholas P. Panos Senior Special Counsel Office of Mergers & Acquisitions U. S. Securities and Exchange Commission Division of Corporation Finance 100 F Street N.E. Washington, DC 20549 Re: Cubist Pharmaceuticals, Inc. Schedule 14D-9 Filed December 19, 2014 File No. 5-47321 Dear Ms. Kohl and Mr. Panos: Cubist Pharmaceuticals, Inc. (the “Com

December 31, 2014 CORRESP

CBST / CORRESP - -

CORRESP HUGHES HUBBARD & REED LLP ONE BATTERY PARK PLAZA NEW YORK, NEW YORK 10004-1482 TELEPHONE: 212-837-6000 FAX: 212-422-4726 HUGHESHUBBARD.

December 31, 2014 SC 14D9/A

CBST / SC 14D9/A - - SC 14D9/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 2) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 22

December 30, 2014 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T AMENDMENT NO. 3

SC TO-T Amendment No. 3 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) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (id

December 30, 2014 SC 14D9/A

CBST / SC 14D9/A - - SC 14D9/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 22

December 23, 2014 EX-99.(A)(1)(N)

Merck Announces Acquisition of Cubist

Exhibit (a)(1)(N) Exhibit (a)(1)(N) Merck Announces Acquisition of Cubist December 23, 2014 (Updated) MERCK Be well Forward-Looking Statement This communication includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995.

December 23, 2014 SC TO-T/A

MRK / Merck & Co., Inc. SC TO-T/A - - SC TO-T/A AMENDMENT NO. 2

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. 2) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offe

December 22, 2014 SC TO-T/A

CBST / / Merck & Co., Inc. - SC TO-T AMENDMENT NO. 1

SC TO-T/A 1 d841515dsctota.htm SC TO-T AMENDMENT NO. 1 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. 1) CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (issuer)) MAVEC CORPORATION (Offeror) a wholly owned subsidiary of MERCK & CO., INC. (Offero

December 22, 2014 8-K

Financial Statements and Exhibits, Other Events

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 19, 2014 CUBIST PHARMACEUTICALS, INC.

December 22, 2014 EX-99.(B).(2)

BRIDGE LOAN AGREEMENT dated as of December 22, 2014 MERCK & CO., INC., as Borrower, The LENDERS Party Hereto JPMORGAN CHASE BANK, N.A., as Administrative Agent J.P. MORGAN SECURITIES LLC and DEUTSCHE BANK SECURITIES INC. Joint Lead Arrangers and Join

EX-99.(B).(2) 2 d841515dex99b2.htm EXHIBIT (B).(2) Exhibit (b)(2) BRIDGE LOAN AGREEMENT dated as of December 22, 2014 among MERCK & CO., INC., as Borrower, The LENDERS Party Hereto and JPMORGAN CHASE BANK, N.A., as Administrative Agent J.P. MORGAN SECURITIES LLC and DEUTSCHE BANK SECURITIES INC. Joint Lead Arrangers and Joint Bookrunners DEUTSCHE BANK SECURITIES INC. Syndication Agent TABLE OF CON

December 22, 2014 EX-99.1

Cubist Announces FDA Approval of New Antibiotic ZERBAXA™ (Ceftolozane/Tazobactam) for Complicated Urinary Tract and Complicated Intra-abdominal Infections ZERBAXA addresses certain serious and resistant Gram-negative bacteria First new antibiotic app

Exhibit 99.1 Cubist Announces FDA Approval of New Antibiotic ZERBAXA™ (Ceftolozane/Tazobactam) for Complicated Urinary Tract and Complicated Intra-abdominal Infections ZERBAXA addresses certain serious and resistant Gram-negative bacteria First new antibiotic approved in U.S. under the GAIN Act that treats Gram-negative bacteria Lexington, Mass., December 19, 2014 –Cubist Pharmaceuticals, Inc. (NA

December 19, 2014 EX-99.A(1)(C)

NOTICE OF GUARANTEED DELIVERY For Tender of Shares of Common Stock CUBIST PHARMACEUTICALS, INC. a Delaware corporation $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 MAVEC CORPORATION a wholly-owned subsidiary of MERC

EX-99.A(1)(C) Exhibit (a)(1)(C) NOTICE OF GUARANTEED DELIVERY For Tender of Shares of Common Stock of CUBIST PHARMACEUTICALS, INC. a Delaware corporation at $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 by MAVEC CORPORATION a wholly-owned subsidiary of MERCK & CO., INC. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT THE END OF THE DAY, IMMEDIATELY AFTER 11:59 P.M.

December 19, 2014 EX-99.(E)(20)

OFFER LETTER AMENDMENT

EX-99.(e)(20) Exhibit (e)(20) OFFER LETTER AMENDMENT December 16, 2014 Patrick Vink Etzelestrasse 20 8707 Uetikon am See Switzerland Dear Patrick, This letter agreement amends the offer letter (the “Offer Letter”) delivered to you by Cubist Pharmaceuticals, Inc. (the “Company”) on November 18, 2014. Except as modified by this letter agreement, the Offer Letter shall remain in full force and effect

December 19, 2014 EX-99.(E)(2)

Rank Among Peers

EX-99.(e)(2) Exhibit (e)(2) Excerpts from Cubist Pharmaceutical Inc.’s Definitive Proxy Statement on Schedule 14A related to the 2014 Annual Meeting of Stockholders as filed with the Securities and Exchange Commission on April 21, 2014. Management Stockholders The following table sets forth information as of April 8, 2014, as reported to us, with respect to the beneficial ownership of our common s

December 19, 2014 8-K

Temporary Suspension of Trading Under Registrant's Employee Benefit Plans, Financial Statements and Exhibits

8-K 1 a14-2654018k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) December 19, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction

December 19, 2014 EX-99.(E)(18)

OFFER LETTER AMENDMENT

EX-99.(e)(18) Exhibit (e)(18) OFFER LETTER AMENDMENT December 16, 2014 Robert J. Perez 39 Bowker Drive Sudbury, MA 01776 Dear Robert, This letter agreement amends the offer letter (the “Offer Letter”) delivered to you by Cubist Pharmaceuticals, Inc. (the “Company”) on October 18, 2014. Except as modified by this letter agreement, the Offer Letter shall remain in full force and effect; provided, th

December 19, 2014 EX-99.A.(1)(F)

Notice of Offer to Purchase for Cash All Outstanding Shares of Common Stock CUBIST PHARMACEUTICALS, INC. a Delaware corporation $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 MAVEC CORPORATION a wholly owned subsidiar

EX-99.A(1)(F) Exhibit (a)(1)(F) This announcement is neither an offer to purchase nor a solicitation of an offer to sell Shares (as defined below), and the provisions herein are subject in their entirety to the provisions of the Offer (as defined below). The Offer is made solely by the Offer to Purchase, dated December 19, 2014, and the related Letter of Transmittal and any amendments or supplemen

December 19, 2014 EX-99.(E)(16)

October 18, 2014

EX-99.(e)(16) Exhibit (e)(16) October 18, 2014 Robert J. Perez 39 Bowker Drive Sudbury, MA 01776 Dear Robert, I am pleased to confirm your promotion to Chief Executive Officer effective 1/1/15. Base Salary: Effective 1/1/15 your annual base salary will increase to $800,000. Bonus: Your annual short-term incentive target will increase under the Management Incentive Plan to 100% of your base salary.

December 19, 2014 EX-99.A(1)(K)

Merck Begins Tender Offer to Acquire Cubist

EX-99.A(1)(K) Exhibit (a)(1)(K) News Release FOR IMMEDIATE RELEASE Media Contacts: Lainie Keller Investor Contacts: Joe Romanelli (908) 236-5036 Steve Cragle (908) 740-1801 (908) 740-1986 Justin Holko (908) 740-1879 Merck Begins Tender Offer to Acquire Cubist KENILWORTH, N.J., Dec. 19, 2014 – Merck (NYSE: MRK), known as MSD outside the United States and Canada, is commencing today, through a subsi

December 19, 2014 EX-99.A(1)(E)

Offer To Purchase For Cash All Outstanding Shares of Common Stock CUBIST PHARMACEUTICALS, INC. a Delaware corporation $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 MAVEC CORPORATION a wholly-owned subsidiary of MERCK

EX-99.A(1)(E) Exhibit (a)(1)(E) Offer To Purchase For Cash All Outstanding Shares of Common Stock of CUBIST PHARMACEUTICALS, INC. a Delaware corporation at $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 by MAVEC CORPORATION a wholly-owned subsidiary of MERCK & CO., INC. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT THE END OF THE DAY, IMMEDIATELY AFTER 11:59 P.M.,

December 19, 2014 EX-99.A(1)(B)

LETTER OF TRANSMITTAL To Tender Shares of Common Stock CUBIST PHARMACEUTICALS, INC. a Delaware corporation $102.00 NET PER SHARE Pursuant to the Offer to Purchase Dated December 19, 2014 MAVEC CORPORATION a wholly owned subsidiary of MERCK & CO., INC

EX-99.A(1)(B) Exhibit (a)(1)(B) LETTER OF TRANSMITTAL To Tender Shares of Common Stock of CUBIST PHARMACEUTICALS, INC. a Delaware corporation at $102.00 NET PER SHARE Pursuant to the Offer to Purchase Dated December 19, 2014 by MAVEC CORPORATION a wholly owned subsidiary of MERCK & CO., INC. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT THE END OF THE DAY, IMMEDIATELY AFTER 11:59 P.M., EASTERN TI

December 19, 2014 EX-99.1

Cubist Pharmaceuticals, Inc. Reason for the Tender Offer Blackout Period and This Notice

EX-99.1 2 a14-265401ex99d1.htm EX-99.1 Exhibit 99.1 Cubist Pharmaceuticals, Inc. Reason for the Tender Offer Blackout Period and This Notice Pursuant to the requirements of Section 306(a) of the Sarbanes-Oxley Act of 2002 and Regulation BTR (i.e., Blackout Trading Restriction), promulgated by the Securities and Exchange Commission (“SEC”), this notice has been provided in order to notify you of a

December 19, 2014 EX-99.A(1)(D)

Offer To Purchase For Cash All Outstanding Shares of Common Stock CUBIST PHARMACEUTICALS, INC. a Delaware corporation $102.00 NET PER SHARE Pursuant to the Offer to Purchase dated December 19, 2014 MAVEC CORPORATION a wholly-owned subsidiary of MERCK

EX-99-A(1)(D) Exhibit (a)(1)(D) Offer To Purchase For Cash All Outstanding Shares of Common Stock of CUBIST PHARMACEUTICALS, INC.

December 19, 2014 EX-99.B(1)

J.P. MORGAN SECURITIES LLC JPMORGAN CHASE BANK, N.A. 383 Madison Avenue New York, NY 10179

EX-99.B(1) Exhibit (b)(1) J.P. MORGAN SECURITIES LLC JPMORGAN CHASE BANK, N.A. 383 Madison Avenue New York, NY 10179 DEUTSCHE BANK SECURITIES INC. DEUTSCHE BANK AG CAYMAN ISLANDS 60 Wall Street New York, NY 10005 PERSONAL AND CONFIDENTIAL December 8, 2014 Merck & Co., Inc. 2000 Galloping Hill Rd. K5-3008A Kenilworth, NJ 07033 Attention: Mark McDonough, Vice President and Treasurer Project Diego Co

December 19, 2014 EX-99.A.(1)(L)

NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC. 401(K) PLAN Date: December 19, 2014 The Tender Offer

EX-99.A(1)(L) Exhibit (a)(1)(L) NOTICE TO PARTICIPANTS IN THE CUBIST PHARMACEUTICALS, INC. 401(K) PLAN Date: December 19, 2014 The Tender Offer As you may know, Mavec Corporation, a Delaware corporation (“Purchaser”), a wholly-owned subsidiary of Merck & Co., Inc., a New Jersey corporation (“Parent”) has offered to purchase each of the issued and outstanding shares of common stock, $0.001 par valu

December 19, 2014 EX-99.A(1)(A)

Offer to Purchase for Cash All Outstanding Shares of Common Stock Cubist Pharmaceuticals, Inc. $102.00 Net Per Share Mavec Corporation a wholly-owned subsidiary of Merck & Co., Inc. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT THE END OF THE DAY, I

EX-99.A(1)(A) Table of Contents Exhibit (a)(1)(A) Offer to Purchase for Cash All Outstanding Shares of Common Stock of Cubist Pharmaceuticals, Inc. at $102.00 Net Per Share by Mavec Corporation a wholly-owned subsidiary of Merck & Co., Inc. THE OFFER AND WITHDRAWAL RIGHTS WILL EXPIRE AT THE END OF THE DAY, IMMEDIATELY AFTER 11:59 p.m. EASTERN TIME ON TUESDAY, JANUARY 20, 2015, UNLESS THE OFFER IS

December 19, 2014 EX-99.(E)(15)

-2-

EX-99.(e)(15) Exhibit (e)(15) December 18, 2014 Via Hand Delivery Michael W. Bonney Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, MA 02421 RE: Confidential Separation Agreement and General Release Dear Mike: This letter agreement (the “Amendment”) amends the Separation Agreement and General Release (the “Agreement”) between you and Cubist Pharmaceuticals, Inc. (“Cubist”). All capitalize

December 19, 2014 SC 14D9

CBST / SC 14D9 - - SC 14D9

SC 14D9 UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT PURSUANT TO SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 229678

December 19, 2014 SC TO-T

MRK / Merck & Co., Inc. SC TO-T - - SC TO-T

SC TO-T 1 d839384dsctot.htm SC TO-T UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE TO (RULE 14D-100) Tender Offer Statement Pursuant to Section 14(d)(1) or 13(e)(1) of the Securities Exchange Act of 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) MAVEC CORPORATION (Offeror) MERCK & CO., INC. (Parent of Offeror) (Names of Filing Persons) COMMON STOCK, $

December 19, 2014 EX-99.(E)(14)

October 20, 2014

EX-99.(e)(14) Exhibit (e)(14) EXECUTION COPY October 20, 2014 Via Hand Delivery Michael W. Bonney Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, MA 02421 RE: Confidential Separation Agreement and General Release Dear Mike: This Separation Agreement and General Release (the “Agreement”) sets forth the understanding between you and Cubist Pharmaceuticals, Inc. (“Cubist”) relating to your v

December 19, 2014 EX-99.(E)(19)

November 18, 2014

EX-99.(e)(19) Exhibit (e)(19) November 18, 2014 Patrick Vink Etzelstrasse 20 8707 Uetikon am See Switzerland Dear Patrick: Congratulations! We are very enthusiastic about you becoming the Chief Operation Officer for Cubist Pharmaceuticals, Inc. (“Cubist). Though you will hold that appointment beginning on January 1, 2015, from January 1-May 31, 2015, you will perform the duties of that role as an

December 19, 2014 EX-99.A(1)(M)

NOTICE TO PARTICIPANTS OF CUBIST PHARMACEUTICALS, INC. 2014 EMPLOYEE STOCK PURCHASE PLAN

EX-99.A(1)(M) Exhibit (a)(1)(M) NOTICE TO PARTICIPANTS OF CUBIST PHARMACEUTICALS, INC. 2014 EMPLOYEE STOCK PURCHASE PLAN December 19, 2014 Dear Plan Participant: The Tender Offer You are receiving this notice because you hold shares in the Cubist Pharmaceuticals, Inc. 2014 Employee Stock Purchase Plan (the “ESPP”). As you may know, Mavec Corporation, a wholly-owned subsidiary of Merck & Co., Inc.

December 19, 2014 EX-99.(E)(17)

- 1 -

EX-99.(E)(17) 6 d839956dex99e17.htm EX-99.(E)(17) Exhibit (e)(17) EXECUTION COPY January 1, 2015 BY HAND DELIVERY Robert J. Perez Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, MA 02421 Re: Retention Letter Dear Rob: You are a highly valuable employee of Cubist. Cubist wishes to retain you as an employee, and is therefore willing to make certain commitments in order to induce you to rema

December 10, 2014 SC TO-C

MRK / Merck & Co., Inc. SC TO-C - - SC TO-C

SC TO-C 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 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) A Wholly Owned Subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offeror, issue

December 10, 2014 SC14D9C

CBST / SC14D9C - - SC 14D9C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 229678107 (CUSIP Num

December 10, 2014 EX-99.A

Merck Announces Acquisition of Cubist

EX-99.A Merck Announces Acquisition of Cubist December 9, 2014 (Updated) Forward-Looking Statement This communication includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. Forward looking statements include statements regarding the timing and closing of the tender offer and the merger transactio

December 9, 2014 SC TO-C

MRK / Merck & Co., Inc. SC TO-C - - SC TO-C

SC TO-C 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 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) A Wholly Owned Subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offeror, issue

December 9, 2014 EX-99.(A)(5)(A)

December 9, 2014

Exhibit (a)(5)(a) December 9, 2014 BY FACSIMILE AND GURANTEED OVERNIGHT COURIER The Bank of New York Mellon Trust Company, N.

December 9, 2014 SC14D9C

CBST / SC14D9C - - SC14D9C

SC14D9C 1 a14-257792sc14d9c.htm SC14D9C UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of C

December 9, 2014 SC TO-C

CBST / SC TO-C - - SC TO-C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE TO TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Issuer)) 2.50% Convertible Senior Notes due 2017 1.125% Convertible Senior Notes due 2018 1.8

December 9, 2014 15-12B

CBST / 15-12B - - 15-12G

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 15 CERTIFICATION AND NOTICE OF TERMINATION OF REGISTRATION UNDER SECTION 12(g) OF THE SECURITIES EXCHANGE ACT OF 1934 OR SUSPENSION OF DUTY TO FILE REPORTS UNDER SECTIONS 13 AND 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934. Commission File Number 001-36151 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specifie

December 9, 2014 EX-99.A

Merck Statement Regarding CUBICIN Patent Litigation Company Reaffirms Transaction To Proceed as Planned; Expected to Close in First Quarter of 2015

EX-99.A Statement Media Contacts: Lainie Keller Investor Contacts: Joe Romanelli (908) 236-5036 Steve Cragle (908) 740-1801 (908) 740-1986 Justin Holko (908) 740-1879 Merck Statement Regarding CUBICIN Patent Litigation Company Reaffirms Transaction To Proceed as Planned; Expected to Close in First Quarter of 2015 KENILWORTH, N.J., December 9, 2014 – Merck, known as MSD outside the United States an

December 9, 2014 8-K

Financial Statements and Exhibits, Other Events

8-K 1 a14-2577958k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) December 8, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction o

December 9, 2014 EX-99.1

Cubist Comments on CUBICIN Patent Litigation Transaction with Merck Unaffected

Exhibit 99.1 Cubist Comments on CUBICIN Patent Litigation Transaction with Merck Unaffected Lexington, Mass., December 8, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that the U.S. District Court in Delaware has ruled on the company’s patent infringement lawsuit against Hospira, Inc. “We are pleased with the Court’s decision on our re-issue patent, U.S. RE 39,071. This will p

December 8, 2014 EX-99.A

Merck to Acquire Cubist Pharmaceuticals for $102 Per Share in Cash Acquisition Augments Merck’s Strong Foundation and Opportunity for Growth in Hospital Acute Care Market

EX-99.A News Release FOR IMMEDIATE RELEASE Merck Media Contacts: Lainie Keller Investor Contacts: Joe Romanelli (908) 406-1459 (908) 740-1986 Steve Cragle (908) 740-1801 Justin Holko (908) 740-1879 Cubist Media Contact: Julie DiCarlo (781) 860-8063 Investor Contact: Eileen C. McIntyre (781) 860-8100 Merck to Acquire Cubist Pharmaceuticals for $102 Per Share in Cash Acquisition Augments Merck’s Str

December 8, 2014 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Amendments to Articles of Incorporation or Bylaws; Change in Fiscal Year, Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Other Events

8-K 1 a14-2577718k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) December 7, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction o

December 8, 2014 SC14D9C

CBST / SC14D9C - - SC 14D9C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14D-9 SOLICITATION/RECOMMENDATION STATEMENT UNDER SECTION 14(d)(4) OF THE SECURITIES EXCHANGE ACT OF 1934 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company) CUBIST PHARMACEUTICALS, INC. (Name of Person(s) Filing Statement) Common Stock, par value $0.001 per share (Title of Class of Securities) 229678107 (CUSIP Num

December 8, 2014 EX-2.1

AGREEMENT AND PLAN OF MERGER MERCK & CO., INC., MAVEC CORPORATION CUBIST PHARMACEUTICALS, INC. Dated as of DECEMBER 8, 2014

EX-2.1 2 a14-257771ex2d1.htm EX-2.1 Exhibit 2.1 EXECUTION VERSION AGREEMENT AND PLAN OF MERGER among MERCK & CO., INC., MAVEC CORPORATION and CUBIST PHARMACEUTICALS, INC. Dated as of DECEMBER 8, 2014 TABLE OF CONTENTS Page ARTICLE I. THE OFFER 2 Section 1.1. The Offer 2 Section 1.2. Company Consent; Schedule 14D-9 4 Section 1.3. Stockholder Lists 4 Section 1.4. Withholding 5 ARTICLE II. THE MERGER

December 8, 2014 EX-99.1

Merck to Acquire Cubist Pharmaceuticals for $102 Per Share in Cash Acquisition Augments Merck’s Strong Foundation and Opportunity for Growth in Hospital Acute Care Market

Exhibit 99.1 News Release FOR IMMEDIATE RELEASE Merck Media Contacts: Lainie Keller Investor Contacts: Joe Romanelli (908) 406-1459 (908) 740-1986 Steve Cragle Justin Holko (908) 740-1801 (908) 740-1879 Cubist Media Contact: Julie DiCarlo Investor Contact: Eileen C. McIntyre (781) 860-8063 (781) 860-8100 Merck to Acquire Cubist Pharmaceuticals for $102 Per Share in Cash Acquisition Augments Merck’

December 8, 2014 EX-10.1

CUBIST PHARMACEUTICALS, INC. 2014 SEVERANCE PLAN AND SUMMARY PLAN DESCRIPTION Effective December 8, 2014

Exhibit 10.1 CUBIST PHARMACEUTICALS, INC. 2014 SEVERANCE PLAN AND SUMMARY PLAN DESCRIPTION Effective December 8, 2014 1. Establishment of This Plan. Cubist Pharmaceuticals, Inc. (“Cubist” and together with its subsidiaries, the “Company”), hereby establishes the Cubist Pharmaceuticals, Inc. 2014 Severance Plan, (the “Plan”), as an unfunded severance pay plan, which is intended to be a welfare bene

December 8, 2014 SC TO-C

MRK / Merck & Co., Inc. SC TO-C - - SC TO-C

SC TO-C 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 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) A Wholly Owned Subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offeror, issue

December 8, 2014 EX-99.A

Merck Announces Acquisition of Cubist December 8, 2014 MERCK Be Well

EX-99.A Merck Announces Acquisition of Cubist December 8, 2014 MERCK Be Well Forward-Looking Statement This communication includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. Forward looking statements include statements regarding the timing and closing of the tender offer and the merger transa

December 8, 2014 EX-3.1

AMENDED AND RESTATED BY-LAWS OF CUBIST PHARMACEUTICALS, INC.

Exhibit 3.1 AMENDED AND RESTATED BY-LAWS OF CUBIST PHARMACEUTICALS, INC. Table of Contents ARTICLE I. - GENERAL 1 1.1. OFFICES 1 1.2. SEAL 1 1.3. FISCAL YEAR 1 ARTICLE II. - STOCKHOLDERS 1 2.1. PLACE OF MEETINGS 1 2.2. ANNUAL MEETING 1 2.3. SPECIAL MEETING 1 2.4. NOTICE OF MEETING 1 2.5. NOTICE OF STOCKHOLDER BUSINESS AND NOMINATIONS 2 2.6. QUORUM AND ADJOURNMENT 3 2.7. RIGHT TO VOTE; PROXIES 4 2.

December 8, 2014 SC TO-C

MRK / Merck & Co., Inc. SC TO-C - - SC TO-C

SC TO-C 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 CUBIST PHARMACEUTICALS, INC. (Name of Subject Company (Issuer)) MAVEC CORPORATION (Offeror) A Wholly Owned Subsidiary of MERCK & CO., INC. (Offeror) (Names of Filing Persons (identifying status as offeror, issue

November 7, 2014 10-Q

CBST / 10-Q - Quarterly Report - 10-Q

Table of Contents UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 10-Q x QUARTERLY REPORT UNDER SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 FOR THE QUARTERLY PERIOD ENDED SEPTEMBER 30, 2014 OR o TRANSITION REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Commission file number: 001-36151 CUBIST PHARMACEUTICALS, INC. (Exact Na

November 7, 2014 EX-10.1

CONFIDENTIAL TREATMENT AMENDMENT NO. 7 to the MANUFACTURING AND SUPPLY AGREEMENT entered into as of September 30, 2001 by and between ACS Dobfar, SpA and Cubist Pharmaceuticals, Inc.

Exhibit 10.1 CONFIDENTIAL TREATMENT AMENDMENT NO. 7 to the MANUFACTURING AND SUPPLY AGREEMENT entered into as of September 30, 2001 by and between ACS Dobfar, SpA and Cubist Pharmaceuticals, Inc. This AMENDMENT NO. 7 (“Amendment No. 7”), to that certain Manufacturing and Supply Agreement (the “Agreement”) entered into as of September 30, 2001, is made effective this 1st day of July, 2014 (“Amendme

November 6, 2014 8-K

Financial Statements and Exhibits

8-K 1 a14-2373518k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) November 5, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction o

November 6, 2014 EX-99.1

Cubist Names Dr. Patrick Vink Chief Operating Officer

Exhibit 99.1 Cubist Names Dr. Patrick Vink Chief Operating Officer Lexington, Mass., November 5, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that Patrick Vink, M.D., M.B.A., currently Senior Vice President and General Manager of Cubist’s International Business, has been promoted to Executive Vice President and Chief Operating Officer, effective January 1, 2015. In his new ro

October 22, 2014 8-K

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) October 20, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 001-36151 22-3192085 (State or Other Jurisdiction of Incorporation) (Commissio

October 22, 2014 EX-99.1

Cubist Pharmaceuticals Names Robert J. Perez Chief Executive Officer Michael W. Bonney to Become Non-Executive Chair of the Board of Directors Kenneth M. Bate to Become Lead Independent Director

Exhibit 99.1 Cubist Pharmaceuticals Names Robert J. Perez Chief Executive Officer Michael W. Bonney to Become Non-Executive Chair of the Board of Directors Kenneth M. Bate to Become Lead Independent Director Lexington, Mass., October 20, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that its Board of Directors has selected Robert J. Perez as the Company’s Chief Executive Offic

October 21, 2014 EX-99.1

Cubist Reports Third Quarter 2014 Financial Results · Total Net Revenues of $309.2 Million, Up 16% Over Q3 2013 · Non-GAAP Adjusted Operating Income of $99.1 Million; GAAP Operating Income of $67.8 Million · Non-GAAP Diluted EPS of $0.58; GAAP Dilute

Exhibit 99.1 Cubist Reports Third Quarter 2014 Financial Results · Total Net Revenues of $309.2 Million, Up 16% Over Q3 2013 · Non-GAAP Adjusted Operating Income of $99.1 Million; GAAP Operating Income of $67.8 Million · Non-GAAP Diluted EPS of $0.58; GAAP Diluted EPS of $0.29 Lexington, Mass., October 21, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced results for the third qua

October 21, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 21, 2014 CUBIST PHARMACEUTICALS, INC.

August 11, 2014 EX-99.1

Cubist Pharmaceuticals Issues Voluntary Nationwide Recall of Nine Lots of CUBICIN (daptomycin for injection) 500 mg in 10 mL single use vials Following Complaints of Foreign Particulate Matter in Reconstituted Vials

Exhibit 99.1 Cubist Pharmaceuticals Issues Voluntary Nationwide Recall of Nine Lots of CUBICIN (daptomycin for injection) 500 mg in 10 mL single use vials Following Complaints of Foreign Particulate Matter in Reconstituted Vials Contacts CONSUMERS: Cubist Medical Information (877) 282-4786 MEDIA: Julie DiCarlo, (781) 860-8063 Senior Director, Corporate Communications [email protected] Lexin

August 11, 2014 8-K

Financial Statements and Exhibits

8-K 1 a14-1862918k.htm 8-K UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) August 8, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of In

August 6, 2014 8-K

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) August 6, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission Fi

August 6, 2014 EX-99.1

Cubist Pharmaceuticals Issues Voluntary U.S. Recall of Certain Lots of CUBICIN (daptomycin for injection) 500 mg in 10 mL single use vials Due to Presence of Particulate Matter

Exhibit 99.1 Cubist Pharmaceuticals Issues Voluntary U.S. Recall of Certain Lots of CUBICIN (daptomycin for injection) 500 mg in 10 mL single use vials Due to Presence of Particulate Matter Contacts CONSUMERS: Cubist Medical Information (877) 282-4786 MEDIA: Julie DiCarlo, (781) 860-8063 Senior Director, Corporate Communications [email protected] Lexington, Mass., August 6, 2014 — Cubist Ph

July 22, 2014 EX-99.1

Cubist Reports Second Quarter 2014 Financial Results · Total Net Revenues of $294.4 Million, Up 14% Over Q2 2013 · Non-GAAP Adjusted Operating Income of $41.4 Million; GAAP Operating Income of $42.2 Million · Non-GAAP Diluted EPS of $0.23; GAAP Dilut

Exhibit 99.1 Cubist Reports Second Quarter 2014 Financial Results · Total Net Revenues of $294.4 Million, Up 14% Over Q2 2013 · Non-GAAP Adjusted Operating Income of $41.4 Million; GAAP Operating Income of $42.2 Million · Non-GAAP Diluted EPS of $0.23; GAAP Diluted EPS of $0.30 Lexington, Mass., July 22, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced results for the second quar

July 22, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 22, 2014 CUBIST PHARMACEUTICALS, INC.

July 14, 2014 8-K

Entry into a Material Definitive Agreement

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): July 10, 2014 CUBIST PHARMACEUTICALS, INC.

June 23, 2014 8-K

Financial Statements and Exhibits, Other Events - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 20, 2014 CUBIST PHARMACEUTICALS, INC.

June 23, 2014 EX-99.1

Cubist’s SIVEXTRO™ (tedizolid phosphate) Approved in U.S. to Treat Serious Skin Infections—Including Those Caused by MRSA SIVEXTRO offers a short six-day course of therapy to physicians in once daily I.V. and oral treatment options

Exhibit 99.1 Cubist’s SIVEXTRO™ (tedizolid phosphate) Approved in U.S. to Treat Serious Skin Infections—Including Those Caused by MRSA SIVEXTRO offers a short six-day course of therapy to physicians in once daily I.V. and oral treatment options Lexington, Mass., June 20, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) announced today the U.S. Food and Drug Administration (FDA) approved SIVEXTRO

June 4, 2014 S-8 POS

- S-8 POS

As filed with the Securities and Exchange Commission on June 4, 2014 File No. 333-168459 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Its Charter) DELAWARE 22-3192085 (State or Other Jurisdiction of Incorp

June 4, 2014 S-8 POS

- S-8 POS

S-8 POS 1 a14-147854s8pos.htm S-8 POS As filed with the Securities and Exchange Commission on June 4, 2014 File No. 333-155352 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Its Charter) DELAWARE 22-3192085

June 4, 2014 S-8

- S-8

As filed with the Securities and Exchange Commission on June 4, 2014 File No. 333- UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Its Charter) DELAWARE 22-3192085 (State or Other Jurisdiction of Incorporation or Organization) (I.R.S. Employe

June 4, 2014 8-K

Submission of Matters to a Vote of Security Holders - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): June 3, 2014 CUBIST PHARMACEUTICALS, INC.

June 4, 2014 S-8 POS

- S-8 POS

As filed with the Securities and Exchange Commission on June 4, 2014 File No. 333-162764 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Its Charter) DELAWARE 22-3192085 (State or Other Jurisdiction of Incorp

June 4, 2014 S-8 POS

- S-8 POS

As filed with the Securities and Exchange Commission on June 4, 2014 File No. 333-182638 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 POST-EFFECTIVE AMENDMENT NO. 1 TO FORM S-8 REGISTRATION STATEMENT UNDER THE SECURITIES ACT OF 1933 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Its Charter) DELAWARE 22-3192085 (State or Other Jurisdiction of Incorp

June 2, 2014 8-K

Current Report

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) May 30, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission File

May 22, 2014 CORRESP

-

May 22, 2014 Via EDGAR United States Securities and Exchange Commission Attention: Jim B.

May 1, 2014 CORRESP

-

Via EDGAR United States Securities and Exchange Commission Attention: Jim B. Rosenberg, Senior Assistant Chief Accountant Division of Corporation Finance 100 F Street N.E. Washington, DC 20549 Re: Cubist Pharmaceuticals, Inc. Form 10-K for the Fiscal Year Ended December 31, 2013 Filed February 25, 2014 File No. 001-36151 Dear Mr. Rosenberg: Cubist Pharmaceuticals, Inc. (“Cubist” or the “Company”)

April 22, 2014 EX-99.2

Cubist Announces Submission of New Drug Application for Investigational Antibiotic Ceftolozane/tazobactam

Exhibit 99.2 Cubist Announces Submission of New Drug Application for Investigational Antibiotic Ceftolozane/tazobactam Lexington, Mass., April 21, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that it has submitted a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for approval of its investigational antibiotic ceftolozane/tazobactam for the treatment

April 22, 2014 EX-99.1

CUBIST PHARMACEUTICALS REPORTS FIRST QUARTER 2014 FINANCIAL RESULTS · Total Net Revenues of $261.2 Million, Up 14% Over Q1 2013; U.S. CUBICIN Net Revenues of $212.2 Million, Up 5% Over Q1 2013 · Non-GAAP Adjusted Operating Income of $18.8 Million; GA

EX-99.1 2 a14-108351ex99d1.htm EX-99.1 Exhibit 99.1 CUBIST PHARMACEUTICALS REPORTS FIRST QUARTER 2014 FINANCIAL RESULTS · Total Net Revenues of $261.2 Million, Up 14% Over Q1 2013; U.S. CUBICIN Net Revenues of $212.2 Million, Up 5% Over Q1 2013 · Non-GAAP Adjusted Operating Income of $18.8 Million; GAAP Operating Income of $28.3 Million · Non-GAAP Diluted EPS of $0.10; GAAP Diluted EPS of $0.30 Le

April 22, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition, Other Events - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): April 21, 2014 CUBIST PHARMACEUTICALS, INC.

April 21, 2014 DEFA14A

- DEFA14A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 14A Proxy Statement Pursuant to Section 14(a) of the Securities Exchange Act of 1934 (Amendment No. ) Filed by the Registrant x Filed by a Party other than the Registrant o Check the appropriate box: o Preliminary Proxy Statement o Confidential, for Use of the Commission Only (as permitted by Rule 14a-6(e)(2)) o Defin

April 21, 2014 DEF 14A

- DEF 14A

Use these links to rapidly review the document TABLE OF CONTENTS APPENDIX B—2014 EMPLOYEE STOCK PURCHASE PLAN CUBIST PHARMACEUTICALS, INC.

April 1, 2014 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers, Financial Statements and Exhibits, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) March 27, 2014 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission Fi

April 1, 2014 EX-99.1

CUBIST APPOINTS ROBERT J. PEREZ TO BOARD OF DIRECTORS Three Long-Serving Directors to Retire

Exhibit 99.1 CUBIST APPOINTS ROBERT J. PEREZ TO BOARD OF DIRECTORS Three Long-Serving Directors to Retire Lexington, Mass., April 1, 2014 — Cubist (NASDAQ: CBST) today announced the appointment of Robert J. Perez to its Board of Directors. Since 2012, Mr. Perez has served as Cubist’s President and Chief Operating Officer (COO). The Company also announced that in accordance with its Corporate Gover

April 1, 2014 PRE 14A

- PRE 14A

Use these links to rapidly review the document TABLE OF CONTENTS APPENDIX B—2014 EMPLOYEE STOCK PURCHASE PLAN CUBIST PHARMACEUTICALS, INC.

February 28, 2014 EX-99.1

CUBIST ANNOUNCES EMA ACCEPTANCE OF TEDIZOLID MARKETING AUTHORIZATION APPLICATION FOR REVIEW

Exhibit 99.1 CUBIST ANNOUNCES EMA ACCEPTANCE OF TEDIZOLID MARKETING AUTHORIZATION APPLICATION FOR REVIEW Lexington, Mass., February 27, 2014 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that the European Medicines Agency (EMA) has accepted for review the Company’s Marketing Authorization Application (MAA) for its investigational antibiotic tedizolid phosphate. Cubist is seeking ap

February 28, 2014 8-K

Financial Statements and Exhibits, Other Events

8-K 1 a14-704018k.htm 8-K SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 27, 2014 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction (Commission (IRS E

February 21, 2014 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers

8-K 1 a14-646718k.htm 8-K SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): February 14, 2014 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction (Commission (IRS E

February 14, 2014 SC 13G/A

CBST / / Wellington Management Group LLP - DISCLOSURE DOCUMENT Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 7)* Cubist Pharmaceuticals, Inc. (Name of Issuer) Common Stock (Title of Class of Securities) 229678107 (CUSIP Number) December 31, 2013 (Date of Event Which Requires Filing of this Statement) Check the appropriate box to designate the rule pursuant to which

February 13, 2014 SC 13G/A

CBST / / PRICE T ROWE ASSOCIATES INC /MD/ - CBST AS OF 12/31/2013 Passive Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13G Under the Securities Exchange Act of 1934 (Amendment No. 1)* CUBIST PHARMACEUTICALS INC (Name of Issuer) COMMON STOCK (Title of Class of Securities) 229678107 (CUSIP Number) December 31, 2013 (Date of Event which Requires Filing of Statement) Check the appropriate box to designate the Rule pursuant to which this S

February 12, 2014 SC 13G/A

CBST / / VANGUARD GROUP INC Passive Investment

cubistpharmaceuticals.htm - Generated by SEC Publisher for SEC Filing SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 Schedule 13G Under the Securities Exchange Act of 1934 (Amendment No.: 3 )* Name of issuer: Cubist Pharmaceuticals Inc Title of Class of Securities: Common Stock CUSIP Number: 229678107 Date of Event Which Requires Filing of this Statement: December 31, 2013 Check the app

January 23, 2014 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): January 23, 2014 CUBIST PHARMACEUTICALS, INC.

January 23, 2014 EX-99.1

CUBIST REPORTS FOURTH QUARTER AND FULL YEAR 2013 FINANCIAL RESULTS; PROVIDES 2014 REVENUE GUIDANCE · Full Year Total Net Revenues of $1.1 Billion, Up 14% Over 2012 · Full Year Non-GAAP Adjusted Operating Income of $189.7 Million; Full Year GAAP Opera

EX-99.1 2 a14-41751ex99d1.htm EX-99.1 EXHIBIT 99.1 CUBIST REPORTS FOURTH QUARTER AND FULL YEAR 2013 FINANCIAL RESULTS; PROVIDES 2014 REVENUE GUIDANCE · Full Year Total Net Revenues of $1.1 Billion, Up 14% Over 2012 · Full Year Non-GAAP Adjusted Operating Income of $189.7 Million; Full Year GAAP Operating Income of $26.4 Million · Full Year Non-GAAP Diluted EPS of $1.45; Full Year GAAP Diluted EPS

January 13, 2014 8-K

Regulation FD Disclosure, Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): January 13, 2014 CUBIST PHARMACEUTICALS, INC.

January 13, 2014 EX-99.1

CUBIST ANNOUNCES FOURTH QUARTER/FULL-YEAR 2013 REVENUES; PROVIDES PIPELINE UPDATE · 2013 Total Net Revenues of $1.1 Billion, Up 14% Over 2012; Q4 Total Net Revenues of $299.7 Million, Up 22% Over 2012 · CUBICIN Achieves Blockbuster Status with 2013 W

EX-99.1 2 a14-33871ex99d1.htm EX-99.1 Exhibit 99.1 CUBIST ANNOUNCES FOURTH QUARTER/FULL-YEAR 2013 REVENUES; PROVIDES PIPELINE UPDATE · 2013 Total Net Revenues of $1.1 Billion, Up 14% Over 2012; Q4 Total Net Revenues of $299.7 Million, Up 22% Over 2012 · CUBICIN Achieves Blockbuster Status with 2013 Worldwide Sales of over $1 Billion · 2013 U.S. CUBICIN Net Product Revenues of $908.0 Million, Up 12

January 2, 2014 EX-24

EXHIBIT 24 Cubist Pharmaceuticals Inc

Steven C Gilman POA EXHIBIT 24 Cubist Pharmaceuticals Inc Power of Attorney for Executing Forms 3, 4 and 5 Know all men by these presents, that the undersigned, director or officer, or both, of Cubist Pharmaceuticals Inc, hereby constitutes and appoints each of Michael W.

December 18, 2013 8-K/A

Financial Statements and Exhibits - 8-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 24, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commissi

December 16, 2013 EX-99.1

CUBIST ANNOUNCES POSITIVE TOP-LINE RESULTS FROM PHASE 3 TRIAL OF CEFTOLOZANE/TAZOBACTAM IN INTRA-ABDOMINAL INFECTIONS INVESTIGATIONAL ANTIBIOTIC MEETS PRIMARY ENDPOINT IN SECOND OF TWO INDICATIONS

Exhibit 99.1 CUBIST ANNOUNCES POSITIVE TOP-LINE RESULTS FROM PHASE 3 TRIAL OF CEFTOLOZANE/TAZOBACTAM IN INTRA-ABDOMINAL INFECTIONS INVESTIGATIONAL ANTIBIOTIC MEETS PRIMARY ENDPOINT IN SECOND OF TWO INDICATIONS Lexington, Mass., December 16, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced positive top-line results from the Company’s pivotal Phase 3 clinical trial of its antibioti

December 16, 2013 8-K

Financial Statements and Exhibits, Other Events

8-K 1 a13-2631428k.htm 8-K SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): December 16, 2013 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction (Commission (IRS

November 26, 2013 8-K

Other Events

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): November 26, 2013 CUBIST PHARMACEUTICALS, INC.

November 25, 2013 EX-99.1

CUBIST ANNOUNCES POSITIVE TOP-LINE RESULTS FROM PHASE 3 TRIAL OF INVESTIGATIONAL ANTIBIOTIC CEFTOLOZANE/TAZOBACTAM IN COMPLICATED URINARY TRACT INFECTIONS

Exhibit 99.1 FOR IMMEDIATE RELEASE CUBIST ANNOUNCES POSITIVE TOP-LINE RESULTS FROM PHASE 3 TRIAL OF INVESTIGATIONAL ANTIBIOTIC CEFTOLOZANE/TAZOBACTAM IN COMPLICATED URINARY TRACT INFECTIONS Lexington, Mass., November 25, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced positive top-line results from the Company’s pivotal Phase 3 clinical trial of its antibiotic candidate ceftoloz

November 25, 2013 8-K

Financial Statements and Exhibits, Other Events

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): November 25, 2013 CUBIST PHARMACEUTICALS, INC.

November 22, 2013 EX-99.3

Unaudited Pro Forma Condensed Combined Financial Statements

Exhibit 99.3 Unaudited Pro Forma Condensed Combined Financial Statements On August 13, 2013, Cubist commenced a tender offer to acquire all the outstanding shares of common stock of Trius, and on September 11, 2013, Cubist completed the acquisition. Cubist acquired 100% of the outstanding shares of Trius, upon which Trius became a wholly-owned subsidiary of Cubist. Trius was a publicly-held biopha

November 22, 2013 8-K/A

Financial Statements and Exhibits, Completion of Acquisition or Disposition of Assets - 8-K/A

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K/A CURRENT REPORT Pursuant to Section 13 or 15(d) of the Securities Exchange Act of 1934 Date of Report (Date of earliest event reported): September 11, 2013 CUBIST PHARMACEUTICALS, INC. (Exact Name of Registrant as Specified in Charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction (Commission (IRS Employer

October 24, 2013 POS AM

- POS AM

As filed with the Securities and Exchange Commission on October 24, 2013 Registration No.

October 24, 2013 EX-4.1

CONTINGENT VALUE RIGHTS AGREEMENT by and between Cubist Pharmaceuticals, Inc. American Stock Transfer & Trust Company, LLC Dated as of October 24, 2013

Exhibit 4.1 CONTINGENT VALUE RIGHTS AGREEMENT by and between Cubist Pharmaceuticals, Inc. and American Stock Transfer & Trust Company, LLC Dated as of October 24, 2013 TABLE OF CONTENTS Page ARTICLE 1 DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION Section 1.1 Definitions 1 Section 1.2 Termination 9 Section 1.3 Compliance and Opinions 9 Section 1.4 Form of Documents Delivered to Trustee 10

October 24, 2013 EX-99.1

CUBIST PHARMACEUTICALS COMPLETES ACQUISITION OF OPTIMER PHARMACEUTICALS Transaction Enhances Company’s Global Leadership in Antibacterials

EX-99.1 3 a13-2269412ex99d1.htm EX-99.1 Exhibit 99.1 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS COMPLETES ACQUISITION OF OPTIMER PHARMACEUTICALS Transaction Enhances Company’s Global Leadership in Antibacterials Lexington, Mass., October 24, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) announced today that it has completed its acquisition of Optimer Pharmaceuticals, Inc. (NASDAQ: OPTR) for

October 24, 2013 EX-10.1

CONTINGENT VALUE RIGHTS AGREEMENT by and between Cubist Pharmaceuticals, Inc. American Stock Transfer & Trust Company, LLC Dated as of October 24, 2013

Exhibit 10.1 CONTINGENT VALUE RIGHTS AGREEMENT by and between Cubist Pharmaceuticals, Inc. and American Stock Transfer & Trust Company, LLC Dated as of October 24, 2013 TABLE OF CONTENTS Page ARTICLE 1 DEFINITIONS AND OTHER PROVISIONS OF GENERAL APPLICATION Section 1.1 Definitions 1 Section 1.2 Termination 9 Section 1.3 Compliance and Opinions 9 Section 1.4 Form of Documents Delivered to Trustee 1

October 24, 2013 8-A12B

- 8-A12B

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-A For Registration of Certain Classes of Securities Pursuant to Section 12(b) or 12(g) of the Securities Exchange Act of 1934 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in its charter) Delaware 22-3192085 (State of Incorporation) (I.R.S. Employer Identification No.) 65 Hayden Avenue Lexington, M

October 24, 2013 8-K

Entry into a Material Definitive Agreement, Termination of a Material Definitive Agreement, Financial Statements and Exhibits, Completion of Acquisition or Disposition of Assets, Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) October 24, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

October 22, 2013 8-K

Financial Statements and Exhibits, Results of Operations and Financial Condition - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 22, 2013 CUBIST PHARMACEUTICALS, INC.

October 22, 2013 EX-99.1

CUBIST REPORTS THIRD QUARTER 2013 FINANCIAL RESULTS · Total Net Revenues of $266.0 Million, Up 12% Over Q3 2012; U.S. CUBICIN Net Revenues of $229.9 Million, Up 10% Over Q3 2012 · Non-GAAP Diluted EPS of $0.41; GAAP Diluted EPS of $(0.50) · Non-GAAP

EXHIBIT 99.1 CUBIST REPORTS THIRD QUARTER 2013 FINANCIAL RESULTS · Total Net Revenues of $266.0 Million, Up 12% Over Q3 2012; U.S. CUBICIN Net Revenues of $229.9 Million, Up 10% Over Q3 2012 · Non-GAAP Diluted EPS of $0.41; GAAP Diluted EPS of $(0.50) · Non-GAAP Adjusted Operating Income of $52.5 Million; GAAP Operating Income of $4.1 Million Lexington, Mass., October 22, 2013 — Cubist Pharmaceuti

October 22, 2013 EX-99.1

CUBIST ANNOUNCES SUBMISSION OF NEW DRUG APPLICATION FOR INVESTIGATIONAL ANTIBIOTIC TEDIZOLID FOR TREATMENT OF SERIOUS SKIN INFECTIONS

Exhibit 99.1 FOR IMMEDIATE RELEASE CUBIST ANNOUNCES SUBMISSION OF NEW DRUG APPLICATION FOR INVESTIGATIONAL ANTIBIOTIC TEDIZOLID FOR TREATMENT OF SERIOUS SKIN INFECTIONS Lexington, Mass., October 22, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced that it has submitted a New Drug Application (NDA) to the U.S. Food and Drug Administration (FDA) for approval of its investigational

October 22, 2013 8-K

Financial Statements and Exhibits, Other Events - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): October 22, 2013 CUBIST PHARMACEUTICALS, INC.

September 26, 2013 8-K

Departure of Directors or Certain Officers; Election of Directors; Appointment of Certain Officers; Compensatory Arrangements of Certain Officers - 8-K

SECURITIES AND EXCHANGE COMMISSION WASHINGTON, DC 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(D) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported): September 23, 2013 CUBIST PHARMACEUTICALS, INC.

September 18, 2013 425

Merger Prospectus - 425

425 1 a13-192387425.htm 425 Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 September 18, 2013 Dear Optimer colleagues: As announced in Optimer’s joint press release with Cubist on Friday morning, the antitrust waiting period applicable to the transactio

September 18, 2013 424B3

MERGER PROPOSED—YOUR VOTE IS VERY IMPORTANT

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS TABLE OF CONTENTS 3 Table of Contents Filed Pursuant to Rule 424(b)(3) Registration No.

September 17, 2013 S-4/A

- S-4/A

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS TABLE OF CONTENTS 3 As filed with the Securities and Exchange Commission on September 17, 2013 Registration No.

September 17, 2013 8-K

Entry into a Material Definitive Agreement, Financial Statements and Exhibits, Completion of Acquisition or Disposition of Assets

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 11, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction (Commission File Number) (I.

September 17, 2013 EX-99.2

CONSENT OF J.P. MORGAN SECURITIES LLC

Exhibit 99.2 CONSENT OF J.P. MORGAN SECURITIES LLC We hereby consent to (i) the use of our opinion letter dated July 30, 2013 to the Board of Directors of Optimer Pharmaceuticals, Inc. (the “Company”) included in Annex C to the Proxy Statement/Prospectus relating to the proposed merger of the Company and Cubist Pharmaceuticals, Inc. (“Cubist”), which is part of the Registration Statement of Cubist

September 17, 2013 EX-10.3

SERIES A CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT by and between OPTIMER PHARMACEUTICALS, INC. CUBIST PHARMACEUTICALS, INC. Dated as of September 16, 2013

Exhibit 10.3 EXECUTION VERSION SERIES A CONVERTIBLE PREFERRED STOCK PURCHASE AGREEMENT by and between OPTIMER PHARMACEUTICALS, INC. and CUBIST PHARMACEUTICALS, INC. Dated as of September 16, 2013 Table of Contents Page ARTICLE I DEFINITIONS Section 1.01 Definitions 1 Section 1.02 Accounting Procedures and Interpretation 5 ARTICLE II AGREEMENT TO SELL AND PURCHASE Section 2.01 Sale and Purchase 5 S

September 17, 2013 EX-99.3

Consent of Centerview Partners LLC

Exhibit 99.3 Consent of Centerview Partners LLC We hereby consent to (i) the inclusion of the text of our opinion letter, dated July 30, 2013, to the Board of Directors of Optimer Pharmaceuticals, Inc. (the “Company”) as Annex D to Amendment No. 1 to the Proxy Statement/Prospectus, filed with the Securities and Exchange Commission (the “Commission”) on September 17, 2013 (the “Proxy Statement/Pros

September 17, 2013 EX-99.1

Signature of Stockholder Date: Signature of Stockholder Date: Note: Please sign exactly as your name or names appear on this Proxy. When shares are held jointly, each holder should sign. When signing as executor, administrator, attorney, trustee or g

Exhibit 99.1 Signature of Stockholder Date: Signature of Stockholder Date: Note: Please sign exactly as your name or names appear on this Proxy. When shares are held jointly, each holder should sign. When signing as executor, administrator, attorney, trustee or guardian, please give full title as such. If the signer is a corporation, please sign full corporate name by duly authorized officer, givi

September 17, 2013 EX-25.1

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE

Exhibit 25.1 UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 FORM T-1 STATEMENT OF ELIGIBILITY UNDER THE TRUST INDENTURE ACT OF 1939 OF A CORPORATION DESIGNATED TO ACT AS TRUSTEE o Check if an Application to Determine Eligibility of a Trustee Pursuant to Section 305(b)(2) AMERICAN STOCK TRANSFER & TRUST COMPANY, LLC (Exact name of trustee as specified in its charter) New Yo

September 17, 2013 EX-10.1

CONTINGENT VALUE RIGHTS AGREEMENT

Exhibit 10.1 CONTINGENT VALUE RIGHTS AGREEMENT THIS CONTINGENT VALUE RIGHTS AGREEMENT, dated as of September 11, 2013 (this “Agreement”), is entered into by and between Cubist Pharmaceuticals, Inc., a Delaware corporation (“Parent”), and Broadridge Corporate Issuer Solutions, Inc., a Pennsylvania corporation, as Rights Agent. RECITALS WHEREAS, Parent, BRGO Corporation, a Delaware corporation (“Sub

September 13, 2013 EX-99.(A)(5)(H)

CUBIST PHARMACEUTICALS ANNOUNCES RESULTS OF TENDER OFFER FOR OUTSTANDING SHARES OF TRIUS THERAPEUTICS

Exhibit 99.(a)(5)(H) CUBIST PHARMACEUTICALS ANNOUNCES RESULTS OF TENDER OFFER FOR OUTSTANDING SHARES OF TRIUS THERAPEUTICS LEXINGTON, Mass. — September 11, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced the results of Cubist’s tender offer to purchase all of the outstanding common shares of Trius Therapeutics, Inc. (NASDAQ: TSRX) for $13.50 per share in cash, plus one Contingen

September 13, 2013 SC 13D/A

TSRX / Trius Therapeutics Inc / CUBIST PHARMACEUTICALS INC - SC 13D/A Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE TO TENDER OFFER STATEMENT UNDER SECTION 14(d)(1) OR SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 6) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

September 13, 2013 8-K

Financial Statements and Exhibits - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 13, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commissio

September 13, 2013 EX-99.1

HART-SCOTT-RODINO WAITING PERIOD EXPIRES FOR CUBIST ACQUISITION OF OPTIMER

Exhibit 99.1 FOR IMMEDIATE RELEASE HART-SCOTT-RODINO WAITING PERIOD EXPIRES FOR CUBIST ACQUISITION OF OPTIMER Lexington, Mass. — September 13, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) and Optimer Pharmaceuticals, Inc. (NASDAQ: OPTR) today announced the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (“HSR”) in connection with the previously

September 13, 2013 EX-99.1

HART-SCOTT-RODINO WAITING PERIOD EXPIRES FOR CUBIST ACQUISITION OF OPTIMER

Exhibit 99.1 FOR IMMEDIATE RELEASE HART-SCOTT-RODINO WAITING PERIOD EXPIRES FOR CUBIST ACQUISITION OF OPTIMER Lexington, Mass. — September 13, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) and Optimer Pharmaceuticals, Inc. (NASDAQ: OPTR) today announced the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (“HSR”) in connection with the previously

September 13, 2013 425

Merger Prospectus - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 13, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commissio

September 11, 2013 SC TO-T/A

- 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 6) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

September 11, 2013 EX-99.(A)(5)(H)

CUBIST PHARMACEUTICALS ANNOUNCES RESULTS OF TENDER OFFER FOR OUTSTANDING SHARES OF TRIUS THERAPEUTICS

Exhibit 99.(a)(5)(H) CUBIST PHARMACEUTICALS ANNOUNCES RESULTS OF TENDER OFFER FOR OUTSTANDING SHARES OF TRIUS THERAPEUTICS LEXINGTON, Mass. — September 11, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced the results of Cubist’s tender offer to purchase all of the outstanding common shares of Trius Therapeutics, Inc. (NASDAQ: TSRX) for $13.50 per share in cash, plus one Contingen

September 10, 2013 EX-10.5

Disclosure of Agency Relationship

Exhibit 10.5 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 EX-10.5

Disclosure of Agency Relationship

Exhibit 10.5 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 425

Merger Prospectus - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 5, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

September 10, 2013 EX-99.1

CUBIST PHARMACEUTICALS ISSUES $800 MILLION OF CONVERTIBLE SENIOR NOTES

Exhibit 99.1 Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS ISSUES $800 MILLION OF CONVERTIBLE SENIOR NOTES Lexington, Mass. — September 10, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced

September 10, 2013 EX-4.1

CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

Exhibit 4.1 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS AND INCORPORATION BY REFERENCE Section 1.01. Definitions 1 Section 1.02. Other Definitions 8 Section 1.03. Rules of Construction 9 Section 1.04. Reference

September 10, 2013 EX-10.7

Disclosure of Agency Relationship

Exhibit 10.7 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 10, 2013 EX-10.6

Disclosure of Agency Relationship

Exhibit 10.6 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 10, 2013 EX-10.10

Disclosure of Agency Relationship

Exhibit 10.10 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5

September 10, 2013 EX-99.1

CUBIST PHARMACEUTICALS ISSUES $800 MILLION OF CONVERTIBLE SENIOR NOTES

Exhibit 99.1 Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS ISSUES $800 MILLION OF CONVERTIBLE SENIOR NOTES Lexington, Mass. — September 10, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced

September 10, 2013 EX-4.2

CUBIST PHARMACEUTICALS, INC. 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

Exhibit 4.2 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS AND INCORPORATION BY REFERENCE Section 1.01. Definitions 1 Section 1.02. Other Definitions 8 Section 1.03. Rules of Construction 9 Section 1.04. Reference

September 10, 2013 EX-4.2

CUBIST PHARMACEUTICALS, INC. 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

Exhibit 4.2 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS AND INCORPORATION BY REFERENCE Section 1.01. Definitions 1 Section 1.02. Other Definitions 8 Section 1.03. Rules of Construction 9 Section 1.04. Reference

September 10, 2013 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Financial Statements and Exhibits, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant, Other Events

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 5, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

September 10, 2013 EX-10.1

Disclosure of Agency Relationship

Exhibit 10.1 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 10, 2013 EX-10.9

Disclosure of Agency Relationship

Exhibit 10.9 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 10, 2013 EX-10.6

Disclosure of Agency Relationship

Exhibit 10.6 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 10, 2013 EX-10.7

Disclosure of Agency Relationship

Exhibit 10.7 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 10, 2013 EX-10.12

Disclosure of Agency Relationship

Exhibit 10.12 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 85

September 10, 2013 EX-10.10

Disclosure of Agency Relationship

Exhibit 10.10 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5

September 10, 2013 EX-10.8

Disclosure of Agency Relationship

Exhibit 10.8 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 EX-10.11

Disclosure of Agency Relationship

Exhibit 10.11 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE

September 10, 2013 EX-10.11

Disclosure of Agency Relationship

EX-10.11 14 a13-204671ex10d11.htm EX-10.11 Exhibit 10.11 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts

September 10, 2013 EX-10.1

Disclosure of Agency Relationship

Exhibit 10.1 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 10, 2013 EX-10.2

Disclosure of Agency Relationship

Exhibit 10.2 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 EX-10.3

Disclosure of Agency Relationship

Exhibit 10.3 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 10, 2013 EX-10.3

Disclosure of Agency Relationship

EX-10.3 6 a13-204671ex10d3.htm EX-10.3 Exhibit 10.3 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Ro

September 10, 2013 EX-10.8

Disclosure of Agency Relationship

Exhibit 10.8 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 EX-10.4

Disclosure of Agency Relationship

Exhibit 10.4 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 10, 2013 EX-4.1

CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE

Exhibit 4.1 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 INDENTURE DATED AS OF SEPTEMBER 10, 2013 THE BANK OF NEW YORK MELLON TRUST COMPANY, N.A., AS TRUSTEE TABLE OF CONTENTS PAGE ARTICLE 1 DEFINITIONS AND INCORPORATION BY REFERENCE Section 1.01. Definitions 1 Section 1.02. Other Definitions 8 Section 1.03. Rules of Construction 9 Section 1.04. Reference

September 10, 2013 EX-10.12

Disclosure of Agency Relationship

Exhibit 10.12 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 85

September 10, 2013 EX-10.9

Disclosure of Agency Relationship

Exhibit 10.9 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 10, 2013 EX-10.2

Disclosure of Agency Relationship

Exhibit 10.2 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 10, 2013 EX-10.4

Disclosure of Agency Relationship

Exhibit 10.4 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 5, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 EX-10.7

Disclosure of Agency Relationship

EX-10.7 9 a13-185513ex10d7.htm EX-10.7 Exhibit 10.7 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Mor

September 5, 2013 SC TO-T/A

- 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 5) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

September 5, 2013 EX-99.1

CUBIST PHARMACEUTICALS PRICES $700 MILLION OF CONVERTIBLE SENIOR NOTES

Exhibit 99.1 Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS PRICES $700 MILLION OF CONVERTIBLE SENIOR NOTES Lexington, Mass. — September 5, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced t

September 5, 2013 EX-10.5

Disclosure of Agency Relationship

Exhibit 10.5 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 5, 2013 EX-10.10

Disclosure of Agency Relationship

Exhibit 10.10 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5

September 5, 2013 EX-10.1

Disclosure of Agency Relationship

Exhibit 10.1 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 425

Merger Prospectus - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 3, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

September 5, 2013 EX-10.7

Disclosure of Agency Relationship

Exhibit 10.7 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 8-K

Entry into a Material Definitive Agreement, Unregistered Sales of Equity Securities, Creation of a Direct Financial Obligation or an Obligation under an Off-Balance Sheet Arrangement of a Registrant - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 3, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

September 5, 2013 EX-10.12

Disclosure of Agency Relationship

EX-10.12 14 a13-185513ex10d12.htm EX-10.12 Exhibit 10.12 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent f

September 5, 2013 EX-10.11

Disclosure of Agency Relationship

Exhibit 10.11 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE

September 5, 2013 EX-10.9

Disclosure of Agency Relationship

Exhibit 10.9 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-10.8

Disclosure of Agency Relationship

EX-10.8 10 a13-185513ex10d8.htm EX-10.8 Exhibit 10.8 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 024

September 5, 2013 EX-10.4

Disclosure of Agency Relationship

Exhibit 10.4 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 EX-10.3

- EX-10.3

Exhibit 10.3 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-1.1

CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 PURCHASE AGREEMENT

Exhibit 1.1 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 PURCHASE AGREEMENT September 4, 2013 Morgan Stanley & Co. LLC 1585 Broadway New York, New York 10036 Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019 RBC Capital Markets, LLC Three World Financial Center 200 Vesey Street New York, New York 10

September 5, 2013 EX-10.6

Disclosure of Agency Relationship

Exhibit 10.6 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-10.5

Disclosure of Agency Relationship

Exhibit 10.5 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 5, 2013 EX-10.2

Disclosure of Agency Relationship

EX-10.2 4 a13-185513ex10d2.htm EX-10.2 Exhibit 10.2 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 0242

September 5, 2013 EX-10.10

Disclosure of Agency Relationship

Exhibit 10.10 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5

September 5, 2013 EX-10.1

Disclosure of Agency Relationship

Exhibit 10.1 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 EX-99.1

CUBIST PHARMACEUTICALS PRICES $700 MILLION OF CONVERTIBLE SENIOR NOTES

Exhibit 99.1 Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS PRICES $700 MILLION OF CONVERTIBLE SENIOR NOTES Lexington, Mass. — September 5, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced t

September 5, 2013 EX-1.1

CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 PURCHASE AGREEMENT

EX-1.1 2 a13-185513ex1d1.htm EX-1.1 Exhibit 1.1 EXECUTION VERSION CUBIST PHARMACEUTICALS, INC. 1.125% CONVERTIBLE SENIOR NOTES DUE 2018 1.875% CONVERTIBLE SENIOR NOTES DUE 2020 PURCHASE AGREEMENT September 4, 2013 Morgan Stanley & Co. LLC 1585 Broadway New York, New York 10036 Barclays Capital Inc. 745 Seventh Avenue New York, New York 10019 RBC Capital Markets, LLC Three World Financial Center 20

September 5, 2013 EX-10.8

Disclosure of Agency Relationship

Exhibit 10.8 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE:

September 5, 2013 EX-10.3

Disclosure of Agency Relationship

Exhibit 10.3 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-10.6

- EX-10.6

Exhibit 10.6 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-10.4

Disclosure of Agency Relationship

Exhibit 10.4 Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5th Floor New York, NY 10036 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: Morgan Stanley & Co. International plc c/o Morgan Stanley & Co. LLC 1585 Broadway, 5t

September 5, 2013 EX-10.11

Disclosure of Agency Relationship

EX-10.11 13 a13-185513ex10d11.htm EX-10.11 Exhibit 10.11 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts

September 5, 2013 EX-10.9

Disclosure of Agency Relationship

Exhibit 10.9 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 858

September 5, 2013 EX-10.12

Disclosure of Agency Relationship

Exhibit 10.12 RBC Capital Markets, LLC 3 World Financial Center 200 Vesey Street New York, New York 10281 Telephone: (212) 858-7000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 02421 ATTENTION: General Counsel TELEPHONE: (781) 860-8660 FACSIMILE: (781) 240-1076 FROM: RBC Capital Markets, LLC as agent for Royal Bank of Canada TELEPHONE: (212) 85

September 5, 2013 EX-10.2

Disclosure of Agency Relationship

EX-10.2 4 a13-185513ex10d2.htm EX-10.2 Exhibit 10.2 Barclays Bank PLC 5 The North Colonnade Canary Wharf, London E14 4BB Facsimile: +44(20)77736461 Telephone: +44 (20) 777 36810 c/o Barclays Capital Inc. as Agent for Barclays Bank PLC 745 Seventh Ave New York, NY 10019 Telephone: +1 212 412 4000 DATE: September 4, 2013 TO: Cubist Pharmaceuticals, Inc. 65 Hayden Avenue Lexington, Massachusetts 0242

September 3, 2013 SC TO-T/A

- 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 4) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

September 3, 2013 8-K

Other Events - 8-K

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) September 3, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission

September 3, 2013 EX-99.1

CUBIST PHARMACEUTICALS ANNOUNCES PROPOSED OFFERING OF $600 MILLION OF CONVERTIBLE SENIOR NOTES Notes to be Offered in Two $300 Million Series, Due in 2018 and 2020

Exhibit 99.1 CUBIST PHARMACEUTICALS ANNOUNCES PROPOSED OFFERING OF $600 MILLION OF CONVERTIBLE SENIOR NOTES Notes to be Offered in Two $300 Million Series, Due in 2018 and 2020 Lexington, Mass. — September 3, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) today announced its intention to commence an offering, subject to market and other conditions, of $600 million in convertible senior unsecur

August 29, 2013 EX-99.(A)(5)(G)

CUBIST ANNOUNCES EXPIRATION OF HART-SCOTT-RODINO WAITING PERIOD FOR ACQUISITION OF TRIUS

Exhibit 99.(a)(5)(G) CUBIST ANNOUNCES EXPIRATION OF HART-SCOTT-RODINO WAITING PERIOD FOR ACQUISITION OF TRIUS Lexington, Mass. — August 29, 2013 — Cubist Pharmaceuticals, Inc. (NASDAQ: CBST) and Trius Therapeutics, Inc. (NASDAQ: TSRX) today announced the expiration of the waiting period under the Hart-Scott-Rodino Antitrust Improvements Act of 1976 (“HSR”) in connection with Cubist’s previously an

August 29, 2013 EX-99.1

CUBIST PHARMACEUTICALS ISSUES VOLUNTARY NATIONWIDE RECALL OF FOUR LOTS OF CUBICIN (DAPTOMYCIN FOR INJECTION) 500MG IN 10ML SINGLE USE VIALS DUE TO PRESENCE OF PARTICULATE MATTER

Exhibit 99.1 FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS ISSUES VOLUNTARY NATIONWIDE RECALL OF FOUR LOTS OF CUBICIN (DAPTOMYCIN FOR INJECTION) 500MG IN 10ML SINGLE USE VIALS DUE TO PRESENCE OF PARTICULATE MATTER Contacts: CONSUMERS Cubist Medical Information (877) 282-4786 MEDIA Julie DiCarlo, (781) 860-8063 Senior Director, Corporate Communications [email protected] FOR IMMEDIATE RELEASE

August 29, 2013 8-K

Financial Statements and Exhibits

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 FORM 8-K CURRENT REPORT PURSUANT TO SECTION 13 OR 15(d) OF THE SECURITIES EXCHANGE ACT OF 1934 Date of Report (Date of earliest event reported) August 28, 2013 CUBIST PHARMACEUTICALS, INC. (Exact name of registrant as specified in charter) Delaware 0-21379 22-3192085 (State or Other Jurisdiction of Incorporation) (Commission F

August 29, 2013 SC TO-T/A

- 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 3) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

August 27, 2013 S-4

- S-4

Use these links to rapidly review the document TABLE OF CONTENTS TABLE OF CONTENTS TABLE OF CONTENTS 3 As filed with the Securities and Exchange Commission on August 27, 2013 Registration No.

August 27, 2013 EX-99.1

Preliminary — subject to completion SPECIAL MEETING OF STOCKHOLDERS OF OPTIMER PHARMACEUTICALS, INC. [·], 2013

Exhibit 99.1 Preliminary — subject to completion SPECIAL MEETING OF STOCKHOLDERS OF OPTIMER PHARMACEUTICALS, INC. [·], 2013 INTERNET — Access “www.voteproxy.com” and follow the on-screen instructions. Have your proxy card available when you access the web page. TELEPHONE — Call toll-free 1-800-PROXIES (1-800-776-9437) in the United States or 1-718-921-8500 from foreign countries from any touch-ton

August 27, 2013 EX-99.2

CONSENT OF J.P. MORGAN SECURITIES LLC

Exhibit 99.2 CONSENT OF J.P. MORGAN SECURITIES LLC We hereby consent to (i) the use of our opinion letter dated July 30, 2013 to the Board of Directors of Optimer Pharmaceuticals, Inc. (the “Company”) included in Annex C to the Proxy Statement/Prospectus relating to the proposed merger of the Company and Cubist Pharmaceuticals, Inc. (“Cubist”), which is part of the Registration Statement of Cubist

August 27, 2013 EX-99.3

Consent of Centerview Partners LLC

Exhibit 99.3 Consent of Centerview Partners LLC We hereby consent to (i) the inclusion of the text of our opinion letter, dated July 30, 2013, to the Board of Directors of Optimer Pharmaceuticals, Inc. (the “Company”) as Annex D to the Proxy Statement/Prospectus, filed with the Securities and Exchange Commission (the “Commission”) on August 27, 2013 (the “Proxy Statement/Prospectus”), included in

August 15, 2013 SC TO-T/A

- 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 2) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTICALS, INC. (Name of Filing Persons (Parent

August 14, 2013 SC TO-T/A

- SC TO-T/A

SC TO-T/A 1 a13-184449sctota.htm 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 SECTION 13(e)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 (Amendment No. 1) TRIUS THERAPEUTICS, INC. (Name of Subject Company) BRGO CORPORATION (Name of Filing Persons (Offeror)) a wholly owned subsidiary of CUBIST PHARMACEUTI

August 13, 2013 EX-99.(A)(5)(F)

CUBIST PHARMACEUTICALS COMMENCES TENDER OFFER FOR ALL OUTSTANDING SHARES OF TRIUS THERAPEUTICS Tender Offer Consistent with Terms Announced on July 30, 2013

Exhibit (a)(5)(F) FOR IMMEDIATE RELEASE CUBIST PHARMACEUTICALS COMMENCES TENDER OFFER FOR ALL OUTSTANDING SHARES OF TRIUS THERAPEUTICS Tender Offer Consistent with Terms Announced on July 30, 2013 Lexington, Mass.

August 13, 2013 EX-99.(A)(1)(E)

Offer to Purchase All Outstanding Shares of Common Stock TRIUS THERAPEUTICS, INC. $13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upon the achi

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

August 13, 2013 EX-99.(D)(4)

MUTUAL NON-DISCLOSURE AGREEMENT THIS MUTUAL NON-DISCLOSURE AGREEMENT (the “Agreement”) is made effective as of July 24, 2012, by and between TRIUS THERAPEUTICS a Delaware corporation, and CUBIST PHARMACEUTICS, INC., a Delaware corporation, to assure

Exhibit (d)(4) MUTUAL NON-DISCLOSURE AGREEMENT THIS MUTUAL NON-DISCLOSURE AGREEMENT (the “Agreement”) is made effective as of July 24, 2012, by and between TRIUS THERAPEUTICS a Delaware corporation, and CUBIST PHARMACEUTICS, INC.

August 13, 2013 SC TO-T

- SC TO-T

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

August 13, 2013 EX-99.(D)(5)

AMENDMENT This Amendment (“Amendment”) is made as of July 1, 2013 (the “Effective Date”) and amends certain portions of the Mutual Non-Disclosure Agreement (the “Agreement”), dated as of July 24, 2012, by and between Trius Therapeutics, Inc. (“Trius”

Exhibit (d)(5) AMENDMENT This Amendment (“Amendment”) is made as of July 1, 2013 (the “Effective Date”) and amends certain portions of the Mutual Non-Disclosure Agreement (the “Agreement”), dated as of July 24, 2012, by and between Trius Therapeutics, Inc.

August 13, 2013 EX-99.(A)(1)(D)

Offer to Purchase All Outstanding Shares of Common Stock TRIUS THERAPEUTICS, INC. $13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upon the achi

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

August 13, 2013 EX-99.(A)(1)(B)

Letter of Transmittal To Tender Shares of Common Stock TRIUS THERAPEUTICS, INC. $13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upon the achiev

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(B) Letter of Transmittal To Tender Shares of Common Stock of TRIUS THERAPEUTICS, INC.

August 13, 2013 EX-99.(A)(5)(E)

[FORM OF SUMMARY ADVERTISEMENT]

EX-99.(A)(5)(E) 7 a2216365zex-99a5e.htm EX-99.(A)(5)(E) Exhibit (a)(5)(E) [FORM OF SUMMARY ADVERTISEMENT] This announcement is neither an offer to purchase nor a solicitation of an offer to sell securities. The Offer (as defined below) is made solely pursuant to the Offer to Purchase (as defined below), and the related Letter of Transmittal (as defined below), and is being made to all holders of S

August 13, 2013 EX-99.(A)(1)(C)

Notice of Guaranteed Delivery for Tender of Shares of Common Stock TRIUS THERAPEUTICS, INC. $13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upo

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 TRIUS THERAPEUTICS, INC.

August 13, 2013 EX-99.(A)(1)(A)

OFFER TO PURCHASE FOR CASH All Outstanding Shares of Common Stock TRIUS THERAPEUTICS, INC. $13.50 per share, plus one non-transferable contingent value right for each share, which represents the contractual right to receive up to $2.00 per share upon

QuickLinks - Click here to rapidly navigate through this document Exhibit (a)(1)(A) OFFER TO PURCHASE FOR CASH All Outstanding Shares of Common Stock of TRIUS THERAPEUTICS, INC.

August 9, 2013 EX-1

JOINT FILING AGREEMENT

Exhibit 1 JOINT FILING AGREEMENT In accordance with Rule 13d-1(k)(1) under the Securities Exchange Act of 1934, as amended, the undersigned hereby agree that this Statement on Schedule 13D (including any amendments thereto) relating to the beneficial ownership of Common Stock, $0.

August 9, 2013 SC 13D

TSRX / Trius Therapeutics Inc / CUBIST PHARMACEUTICALS INC - SC 13D Activist Investment

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 SCHEDULE 13D Under the Securities Exchange Act of 1934 (Amendment No. )* TRIUS THERAPEUTICS, INC. (Name of Issuer) Common Stock, $0.0001 par value per share (Title of Class of Securities) 89685K100 (CUSIP Number) Thomas J. DesRosier Senior Vice President, Chief Legal Officer, General Counsel and Secretary Cubist Pharmaceutical

August 2, 2013 425

Merger Prospectus - 425

Filed by Cubist Pharmaceuticals, Inc. Pursuant to Rule 425 under the Securities Act of 1933, as amended Subject Company: Optimer Pharmaceuticals, Inc. Exchange Act Commission File No: 001-33291 Date Dear Dr. XXX; Earlier this week, Cubist announced our planned acquisitions of both Trius Therapeutics and Optimer Pharmaceuticals. As a key infectious disease expert, we thought it important to convey

August 2, 2013 SC TO-C

- SC TO-C

UNITED STATES SECURITIES AND EXCHANGE COMMISSION WASHINGTON, D.C. 20549 SCHEDULE TO TENDER OFFER STATEMENT UNDER SECTION 14(D)(1) OR SECTION 13(E)(1) OF THE SECURITIES EXCHANGE ACT OF 1934 TRIUS THERAPEUTICS, INC. (Name Of Subject Company (Issuer)) BRGO CORPORATION CUBIST PHARMACEUTICALS, INC. (Names of Filing Persons (Offerors)) Common Stock, par value $0.0001 per share (Title of Class of Securit

August 2, 2013 EX-99.1

65 Hayden Avenue - EX-99.1

Date Dear Dr. XXX; Earlier this week, Cubist announced our planned acquisitions of both Trius Therapeutics and Optimer Pharmaceuticals. As a key infectious disease expert, we thought it important to convey this information to you directly. The prospects of continuing the development and potential commercialization of tedizolid (Trius) and the marketing of DIFICID (Optimer) reaffirms Cubist’s missi

August 1, 2013 EX-99.1

Safe Harbor Statement 2 This presentation and statements in this conference call regarding the proposed transactions contain forward-looking statements. Any statements contained herein which do not describe historical facts, including but not limited

Planned Acquisitions of Trius Therapeutics and Optimer Pharmaceuticals Accelerating Cubist’s Global Leadership in Acute Care July 30, 2013 Exhibit 99.

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