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                                                                   EXHIBIT 10.66

                             CONFIDENTIAL TREATMENT

                                 FIRST AMENDMENT

                TO "COLLABORATIVE RESEARCH AND LICENSE AGREEMENT"

This First Amendment is dated 4th February 2002, and is made between CUBIST
PHARMACEUTICALS, INC. ("CUBIST"), a Delaware corporation having its principal
place of business at 65 Hayden Avenue, Lexington, Massachusetts 02421, U.S.A.,
and NOVARTIS PHARMA AG ("NOVARTIS"), a Swiss corporation having its principal
place of business at Lichtstrasse 35, CH-4002 Basel, Switzerland,.

WHEREAS Cubist and Novartis are parties to a Collaborative Research And License
Agreement, dated 4th February, 1999 (hereafter the "Agreement");

WHEREAS Cubist and Novartis wish to amend the Agreement in accordance with the
terms and conditions of this First Amendment.

THEREFORE, Cubist and Novartis agree as follows:

1.     In SECTION 2.1 ("General") the second sentence shall be amended to read
       as follows: "The Research Program will have a term of [ * ] years,
       unless terminated earlier pursuant to Article 12."

2.     In SECTION 8.1 ("Funding of the Research Program by Novartis") a second
       paragraph shall be added as follows:

       ,,In consideration of Cubist's performance of its obligations under the
       Research Program in the [ * ], Novartis will pay Cubist [ * ] during
       [ * ]. Such funding represents support for [ * ] full-time Cubist
       employees during the [ * ] at a cost of [ * ] per full-time employee. The
       amount payable for the [ * ] shall be paid in advance by certified or
       bank check or wire transfer in United States dollars in four equal
       payments to be paid quarterly upon presentation of an invoice by Cubist.
       (each such payment referred to as a "Research Funding Payment"). Research
       Funding Payments shall be made no later than (a) by the [ * ] business
       day of each [ * ] of the [ * ] or (b) [ * ] days after receipt of the
       corresponding invoice, whichever is the later. Research Funding Payments
       for the [ * ] shall not be credited against [ * ] payments due Cubist
       under Sections 8.2 through 8.4 below:"

3.     In SECTION 8.3.1 ("Technology Transfer Milestone Payments") the
       half-sentence "PROVIDED HOWEVER, that in no event shall Novartis be
       required to pay Cubist under this Section 8.3 more than [ * ]" shall be
       deleted and replaced and superseded by the following:

       "PROVIDED HOWEVER, that in no event shall [ * ]".

4.     SECTION 12.1.1 (,,Expiration of the Research Program") shall be
       deleted and be replaced and superseded in its entirety by the following:

* Confidential Treatment Requested.  Omitted portions filed with the Commission.

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       ,,Unless this Agreement is sooner terminated in accordance with the
       provisions of this Article 12, the term of the Research Program shall
       expire upon the completion of [ * ]"

5.     In SECTION 13.4 (,,Notices"), the part entitled ,,If to Cubist" shall
       be be deleted and be replaced and superseded in its entirety
       by the following:

       ,,If to Cubist:                  Cubist Pharmaceuticals, Inc.
                                        65 Hayden Avenue
                                        Lexington, Massachusetts 02421
                                        Fax:  (781) 861-0566
                                        Attention: Vice President, Research
                                        With a copy to:  Contracts Manager"

6.     All other provisions of the Agreement shall remain unchanged and shall
       continue to be in full force and effect.

7.     This First Amendment will form an integral part of the Agreement.

IN WITNESS WHEREOF, the Parties have executed this Agreement as of the dates
indicated below.

<Table>
<Caption>
CUBIST PHARMACEUTICALS, INC.           NOVARTIS PHARMA AG
<S>    <C>                          <C>    <C>                        <C>
By:       /s/ G.H. Shimer, Jr.      By:       /s/ Paul P. Herrling       /s/ Siegward Stru
       --------------------------          -----------------------    --------------------------

Name:     GH Shimer Jr.             Name:     Prof. P Herrling           Siegward Strub, P.h.D
       --------------------------          -----------------------    --------------------------

Title:    VP, Research              Title: Head of Research           BD&L, Head Research Liaison
       --------------------------          Novartis Pharma AG
                                           WSJ 386.13.06
                                           CH-4002 Basel/Switzerland

Date:     1/31/02                   Date:     7/02/02
       --------------------------          -----------------------
</Table>

* Confidential Treatment Requested.  Omitted portions filed with the Commission.

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EXHIBIT 10(a)    
  

 
 

THE ST. PAUL COMPANIES, INC.
  SENIOR EXECUTIVE PERFORMANCE PLAN    
  

        1.    PURPOSE    

        The
purpose of The St. Paul Companies, Inc. Senior Executive Performance Plan is to permit The St. Paul Companies, Inc. (the "Company"), through awards of annual incentive
compensation which satisfy the requirements for performance-based compensation under Section 162(m) of the Internal Revenue Code, to attract and retain executives and to motivate these
executives to promote the profitability and growth of the Company. 

        2.    DEFINITIONS    

        "AFTER-TAX
OPERATING EARNINGS" shall mean, for each Performance Period, the Company's net income from continuing operations as reported in the Company's income statement for
the Performance Period, adjusted to eliminate the after-tax effects of net realized investment gains or losses in the fixed maturities and real estate portfolios, extraordinary items, and
the cumulative effect of accounting changes, each as defined by accounting principles generally accepted in the United States. This amount will be further adjusted to eliminate the
after-tax impact of any restructuring charges (as reported in the footnotes to the Company's financial statements), losses from catastrophes (as designated by the Insurance Service
Office's Property Claims Service Group, the Lloyd's Claim Office, Swiss Reinsurance Company's sigma report, or a comparable report or organization generally recognized by the insurance industry) in
the Company's "core" businesses (as reported in press releases announcing its financial results), and underwriting results of the businesses that the Company does not treat as "core" businesses in
those press releases. 

        "AWARD"
shall mean the amount granted to a Participant by the Committee for a Performance Period. 

        "BEGINNING
TOTAL COMMON STOCKHOLDERS' EQUITY" shall mean, for each Performance Period, the Company's total common stockholders' equity as reported in the Company's balance sheet for the
beginning of the Performance Period, excluding net unrealized appreciation or depreciation of investments. 

        "BOARD"
shall mean the Board of Directors of the Company. 

        "CODE"
shall mean the Internal Revenue Code of 1986, as amended. 

        "COMMITTEE"
shall mean the Personnel and Compensation Committee of the Board or any subcommittee thereof which meets the requirements of Section 162(m)(4)(C) of the Code. 

        "EXCHANGE
ACT" shall mean the Securities Exchange Act of 1934, as amended. 

        "EXECUTIVE"
shall mean any covered employee as defined in Section 162(m) of the Code and, in the discretion of the Committee, any other executive officer of the Company or its
Subsidiaries. 

        "PARTICIPANT"
shall mean, for each Performance Period, each Executive who is a "covered employee" (as defined in Section 162(m) of the Code) for that Performance Period, unless
otherwise determined by the Committee in its sole discretion. 

        "PERFORMANCE
PERIOD" shall mean the Company's fiscal year or any other period designated by the Committee with respect to which an Award may be granted. 

        "PLAN"
shall mean The St. Paul Companies, Inc. Senior Executive Performance Plan, as amended from time to time. 

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        "RETURN
ON EQUITY" shall mean, for each Performance Period, the percentage equivalent to the fraction resulting from dividing After-Tax Operating Earnings by Beginning Total
Common Stockholders' Equity. 

        "STOCK
PLANS" shall mean The St. Paul Companies, Inc. Amended and Restated 1994 Stock Incentive Plan and/or any prior and successor stock plans adopted or assumed by the Company. 

        "SUBSIDIARY"
shall mean any entity that is directly or indirectly controlled by the Company or any entity, in which the Company has at least a 50% equity interest. 

        3.    ADMINISTRATION    

        The
Plan shall be administered by the Committee, which shall have full authority to interpret the Plan, to establish rules and regulations relating to the operation of the Plan, to
select Participants, to determine the maximum Awards and the amounts of any Awards and to make all determinations and take all other actions necessary or appropriate for the proper administration of
the Plan. Before any payments are made under the Plan, the Committee shall certify in writing that the Return on Equity required by Section 4(b) has been met. The Committee's interpretation of
the Plan, and all actions taken within the scope of its authority, shall be final and binding on the Company, its stockholders and Participants, Executives, former Executives and their respective
successors and assigns. No member of the Committee shall be eligible to participate in the Plan. 

        4.    DETERMINATION OF AWARDS    

        (a)  Prior
to the beginning of each Performance Period, or at such later time as may be permitted by applicable provisions of the Code, the Committee shall establish for each
Participant a maximum Award, expressed as a percentage of the incentive pool for the Performance Period pursuant to paragraph (b) of this section, provided that the total of all such maximum
percentages shall not exceed 100%, and the maximum percentage for any single Participant shall not exceed 50%. 

        (b)  If
the Return on Equity for a Performance Period is greater than 8%, the incentive pool for the Performance Period shall be equal to 1.5% of After-Tax
Operating Earnings. If the Return on Equity for a Performance Period is equal to or less than 8%, the incentive pool shall be $0. 

        (c)  Following
the end of each Performance Period, the Committee may determine to grant to any Participant an Award, which may not exceed the maximum amount specified in
paragraph (a) of this section for such Participant. The aggregate amount of all Awards under the Plan for any Performance Period shall not exceed 100% of the incentive pool pursuant to
paragraph (b) of this section. 

        5.    PAYMENT OF AWARDS    

        Each
Participant shall be eligible to receive, as soon as practicable after the amount of such Participant's Award for a Performance Period has been determined, payment of all or a
portion of that Award. Awards may be paid in cash, stock, restricted stock, options, other stock-based or stock-denominated units or any combination thereof determined by the Committee. Equity or
equity-based awards may be granted under the terms and conditions of the applicable Stock Plan. Payment of the award may be deferred in accordance with a written election by the Participant pursuant
to procedures established by the Committee. 

        6.    AMENDMENTS    

        The
Committee may amend the Plan at any time and from time to time, provided that no such amendment that would require the consent of the stockholders of the Company pursuant to
Section 162(m) of the Code or the Exchange Act, or any other applicable law, rule or regulation, shall be effective without such consent. No such amendment which adversely affects a
Participant's rights to, or interest in, an Award granted prior to the date of the amendment shall be effective unless the Participant shall have agreed thereto in writing. 

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        7.    TERMINATION    

        The
Committee may terminate this Plan at any time. In such event, and notwithstanding any provision of the Plan to the contrary, payment of deferred amounts plus any earnings may be
accelerated with respect to any affected Participant in the discretion of the Committee and paid as soon as practicable; but in no event shall the termination of the Plan adversely affect the rights
of any Participant to deferred amounts previously awarded such Participant, plus any earnings thereon. 

        8.    OTHER PROVISIONS    

        (a)  No
Executive or other person shall have any claim or right to be granted an Award under this Plan until such Award is actually granted. Neither the establishment of this
Plan, nor any action taken hereunder, shall be construed as giving any Executive any right to be retained in the employ of the Company. Nothing contained in this Plan shall limit the ability of the
Company to make payments or awards to Executives under any other plan, agreement or arrangement. 

        (b)  The
rights and benefits of a Participant hereunder are personal to the Participant and, except for payments made following a Participant's death, shall not be subject to
any voluntary or involuntary alienation, assignment, pledge, transfer, encumbrance, attachment, garnishment or other disposition. 

        (c)  Awards
under this Plan shall not constitute compensation for the purpose of determining participation or benefits under any other plan of the Company unless specifically
included as compensation in such plan. 

        (d)  The
Company shall have the right to deduct from Awards any taxes or other amounts required to be withheld by law. 

        (e)  All
questions pertaining to the construction, regulation, validity and effect of the provisions of the Plan shall be determined in accordance with the laws of the State
of Minnesota without regard to principles of conflict of laws. 

        (f)    If
any provision of this Plan would cause Awards not to constitute "qualified performance-based compensation" under Section 162(m) of the Code, that provision
shall be severed from, and shall be deemed not to be a part of, the Plan, but the other provisions hereof shall remain in full force and effect. 

        (g)  No
member of the Committee or the Board, and no officer, employee or agent of the Company shall be liable for any act or action hereunder, whether of commission or
omission, taken by any other member, or by any officer, agent, or employee, or, except in circumstances involving bad faith, for anything done or omitted to be done in the administration of the Plan. 

        9.    EFFECTIVE DATE    

        The
Plan shall be effective as of January 1, 2002, subject to approval by the stockholders of the Company in accordance with Section 162(m) of the Code. 

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EXHIBIT 10(a)

THE ST. PAUL COMPANIES, INC. SENIOR EXECUTIVE PERFORMANCE PLAN

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