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                                                                 Exhibit 10.59

                             CONFIDENTIAL TREATMENT

                       FIRST ADDENDUM TO LICENSE AGREEMENT
            BETWEEN INTERNATIONAL HEALTH MANAGEMENT ASSOCIATES, INC.
            AND CUBIST PHARMACEUTICALS, INC., DATED NOVEMBER 22, 2000

         This Addendum sets forth certain clarifications and amendments to the
License Agreement between International Health Management Associates, Inc.,
("IHMA") and CUBIST Pharmaceuticals, Inc. ("Cubist") dated November 22, 2000,
and is effective the 27th day of September, 2002 ("the License Agreement"). By
this Addendum, the parties hereto memorialize their [*] which, INTER ALIA,
resulted in CUBIST licensing rights under U.S. Patent No. 6,248,360 ("the `360
Patent") from the University of Utah Research Foundation ("UNIVERSITY"), [*] to
IHMA, and the parties executing an Escrow Agreement dated September 27, 2002
("the ESCROW AGREEMENT"). This Addendum is entered into pursuant to Article 8.11
of the License Agreement between the parties. Except to the extent this Addendum
clarifies or amends certain terms and conditions in the License Agreement, all
other terms and conditions of the License Agreement that are not addressed in
this Addendum shall remain in full force and effect, and this Addendum shall
itself be construed and applied so as to be consistent with the terms and
conditions of the License Agreement. This Amendment shall not be construed to
modify or amend any provision of the ESCROW AGREEMENT.

         WHEREAS, IHMA and CUBIST desire [*] concerning the License Agreement;
         and WHEREAS, IHMA and CUBIST have agreed to the terms herein as the
         basis [*]; and

         WHEREAS, IHMA and CUBIST agree that in the resolution of [*] as
memorialized in this Addendum, each has given and received from the other

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consideration that is in addition to the consideration given or received in
their Licensing Agreement.

         NOW THEREFORE, in consideration of the mutual covenants herein
stated, IHMA and CUBIST agree to clarify or amend particular terms of
their License Agreement as follows:

1.       REDUCTION IN LICENSING FEES AND ROYALTIES FOR PAYMENTS TO
THE UNIVERSITY

         In fulfillment of any and all duties under Article 5 of the License
Agreement for IHMA to defend and indemnify and hold CUBIST harmless from and
against any claim, suit, demand or loss as a result of the rights asserted by
the UNIVERSITY in the '360 Patent, from whom CUBIST has obtained an exclusive
license in exchange for certain payments, IHMA and CUBIST agree that, subject to
the provisions of the ESCROW AGREEMENT, any payments by CUBIST due to IHMA under
Article 3.1 and 3.2 of the License Agreement shall be reduced by the amounts
which CUBIST actually pays to the UNIVERSITY under its license.

         In addition, since notice of allowance of IHMA's original patent
application was received before the patent application could be refiled (the
original "milestone" payment), IHMA and CUBIST agree to amend the language of
Section 3.1(b) to provide for payment of this milestone upon filing with the
U.S. Patent and Trademark Office application no. 09/888,114 ("the CIP
Application"), a continuation-in-part of 09/829,405, which is a continuation of
09/598,089, now U.S. Patent No. 6,248,360. IHMA and CUBIST further agree to
amend the language of Section 3.1(c) to reduce by [*] the milestone for
selection of the first single formulation of oral ceftriaxone for clinical
trials, to compensate CUBIST for the milestone it must pay to the UNIVERSITY for
issuance of the CIP. The parties believe that the CIP will issue within a brief
time period before or after selection of the first single formulation of oral

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ceftriaxone for clinical trials. However, provisions for payment of the [*] to
IHMA are made in Section 3.1(c) if the CIP application is finally rejected and
the CIP Application is abandoned.

         Articles 3.1 and 3.2 of the License Agreement are therefore amended to
offset the amounts which CUBIST is obligated to pay in licensing fees, milestone
payments, and royalty payments to the UNIVERSITY. CUBIST shall be entitled to
deduct the appropriate amount of the fee, milestone, or royalty payment made to
the UNIVERSITY from any payment due to IHMA, according to the following
provisions which shall be deemed to supercede Articles 3.1(a)-3.1(h) and Article
3.2(a):

         3.1 LICENSING FEES. The  licensing fees which shall be paid by CUBIST
         to IHMA, are as follows:

                  (a) CUBIST shall pay to IHMA the sum of [*], of which [*]
         shall be paid within five (5) business days of the Effective Date, and
         [*] paid within sixty (60) days of the Effective Date. This payment,
         due IHMA under this Article 3.1(a) and previously made by CUBIST, shall
         be reduced by the amount of [*] to offset the licensing fee paid by
         CUBIST to the UNIVERSITY. And,

                  (b) CUBIST will pay to IHMA the sum of [*] upon filing with
         the U.S. Patent and Trademark Office application no. 09/888,114, a
         continuation in part ("CIP") application to the '360 Patent ("CIP
         application"); And,

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                  (c) CUBIST will pay to IHMA the sum of [*] within thirty (30)
         days of CUBIST selecting the first single oral formulation of oral
         ceftriaxone for clinical trials. CUBIST will pay IHMA an additional [*]
         if the CIP application is finally rejected and the CIP application is
         abandoned. And,

                  (d) CUBIST will pay IHMA the sum of [*] within thirty (30)
         days following the date on which CUBIST completes its initial
         first-into-man study. Initial first-into-man study means, for purposes
         of this milestone payment, a single dose pharmacokinetic study
         (including a study that may be conducted outside the U.S. before any
         Investigational New Drug Application (IND) is filed, or in the U.S.
         after an IND is approved), completion of which means preparation of the
         final report on the data in the study. And,

                  (e) CUBIST will pay IHMA the sum of [*] within thirty (30)
         days following the date on which the United States Patent and Trademark
         Office issues IHMA a patent covering the oral formulation of
         ceftriaxone chosen for clinical development. And,

                  (f) CUBIST will pay IHMA the sum of [*] within thirty (30)
         days following the date on which CUBIST successfully completes its
         first pivotal Phase III clinical drug trials relating to any Licensed
         Products. "Completion," for purposes of this milestone payment, means
         the final report on the data in the first pivotal Phase III clinical
         drug trial. And,

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                  (g) CUBIST will pay IHMA the sum of [*] within thirty (30)
         days following the date on which CUBIST files a New Drug Application
         (NDA) with the FDA covering any Licensed Products. And,

                  (h) CUBIST will pay IHMA the sum of [*] within thirty (30)
         days following the date on which the FDA approves a NDA of CUBIST
         covering any Licensed Products. And,

Article 3.1(i) and 3.1(j) as stated in the License Agreement remain in full
force and effect.

         3.2 ROYALTIES

                  (a) Commencing with the initial sale of Licensed Products in
         any jurisdiction, CUBIST shall pay to IHMA royalties equal to: (i) [*]
         of CUBIST's (and/or its Affiliate's and/or sublicensees) Net Sales of
         Licensed Products in the Territory up to [*]; plus (ii) [*] of CUBIST's
         (and/or its Affiliate's and/or sublicensees') Net Sales of Licensed
         Products in the Territory above [*] up to [*]; plus (iii) [*] of
         CUBIST's (and/or its Affiliate's and/or sublicensees') Net Sales of
         Licensed Products in the Territory above [*].

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Article 3.2(b), 3.2(c), 3.2(d), and 3.2(e) in the License Agreement remain in
full force and effect.

         In the event any fee, milestone payment, or royalty payment due to the
UNIVERSITY is not paid by CUBIST in accordance with the terms of that certain
License Agreement dated December 27, 2001 between CUBIST and the UNIVERSITY,
then CUBIST shall pay to IHMA the amount of that milestone payment due but not
paid to the UNIVERSITY. In the event CUBIST has not paid to the UNIVERSITY, in
accordance with the terms of that certain License Agreement dated December 27,
2001 between CUBIST and the UNIVERSITY, any amount due under its license for
licensing fees and royalties which correspond to the licensing fees or royalties
set out in Article 3.1 of the License Agreement prior to CUBIST's payment to
IHMA, then CUBIST shall pay to IHMA that amount due under the License Agreement
prior to this amendment. If CUBIST thereafter pays the UNIVERSITY a licensing
fee or a royalty for which CUBIST has previously paid IHMA a licensing fee or
royalty which did not include the appropriate deduction as provided herein, then
the amount of the licensing fee or royalty paid to the UNIVERSITY may be
deducted from the next licensing fee or royalty due IHMA under the amended
Article 3.1.

         In the event that any royalty payment by CUBIST to the UNIVERSITY
exceeds, in any quarter, [*] by reason of a defined "minimum royalty due," then
the sum due IHMA shall be reduced by that same difference. The effect of this
provision shall be that the royalties due IHMA will be adjusted only to reflect
royalty payments which CUBIST has actually made to the UNIVERSITY. Insofar as
any payment to the UNIVERSITY under a minimum royalty due results in a reduction
in the royalty paid during a different quarter, then the royalty to be paid to

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IHMA shall be increased, with the effect of paying IHMA the full royalty
specified in the License Agreement before this Addendum, less only CUBIST's
actual payments to the UNIVERSITY.

         In the event that CUBIST pays a milestone payment to the UNIVERSITY for
a subsequent INDIVIDUAL LICENSED PRODUCT (as that term is used in the License
Agreement between CUBIST and the UNIVERSITY) containing ceftriaxone (such as a
pediatric extension for an oral formulation of ceftriaxone), then CUBIST shall
be entitled to deduct the amount of that milestone payment that CUBIST pays to
the UNIVERSITY for a subsequent INDIVIDUAL LICENSED PRODUCT. Other than as
expressly provided in this Addendum, no licensing fee or royalty, nor other
obligation by CUBIST to IHMA, may be reduced nor is affected by additional
licensing fees and/or royalties CUBIST may have to pay to the UNIVERSITY as a
result of licensing any rights under the '360 Patent from the UNIVERSITY.

2.       CUBIST HAS PAID IHMA THE MILESTONE PAYMENTS WITHHELD, LESS THE SUMS
         PAID BY CUBIST TO THE UNIVERSITY FOR ITS LICENSE

         Pursuant to the ESROW AGREEMENT, CUBIST paid to IHMA the sum of [*] in
complete satisfaction of its obligation for the licensing fees required under
Article 3.1(b), (d), and (e) as amended herein (which includes a credit of [*]
reflecting the amount Cubist paid the UNVERSITY for its license), together with
an agreed upon amount of [*], in full satisfaction of any accrued interest
payments. The Escrow Agreement is made an exhibit to this Addendum and, as to
the obligations between CUBIST and IHMA in it, it is made a part hereof.

         This Addendum and the ESCROW AGREEMENT [*] payment of licensing fees
due, and [*] regarding the [*] to and including the date of this Addendum.

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3.       RIGHTS OF IHMA AND CUBIST EACH TO ENTER INTO LICENSES FOR THE '360
         PATENT AND TECHNOLOGY

         A. Upon execution of the Sublicense, CUBIST grants an exclusive
sublicense of the rights granted to CUBIST by the UNIVERSITY, to use the '360
Patent and technology in developing and practicing oral delivery of cefipime and
cefditoren only, as set forth completely in that Sublicense. The Sublicense
between IHMA and CUBIST by which IHMA has the exclusive right to practice the
'360 Patent in connection with cefipime and cefditoren is made a part hereof.

         B. The parties acknowledge that CUBIST declined [*] the "ROFO" ("Right
of First Opportunity") [*] defined in Article 3.6 of the License [*]. Therefore,
all Right of First Opportunity to License IHMA Technology Applicable to Other
Products set out in Article 2.9 of the License Agreement has no further effect.

         C. The parties further acknowledge that in the License Agreement IHMA
reserved to itself all of its rights to use and apply the '360 Patent and
related technology in pharmaceuticals other than ceftriaxone. The parties
further acknowledge that since the License Agreement, in December 2001 CUBIST
obtained an exclusive license of the rights of the UNIVERSITY in the '360 Patent
(which the UNIVERSITY obtained through its employee, Dr. Jeong Soo Lee, the
co-inventor with Dr. Choi). Finally, the parties acknowledge that pursuant to
the License Agreement, CUBIST has fully compensated Dr. Choi for his work for
CUBIST, pursuant to both Article 2.8 and that certain Sponsored Research
Agreement dated February 1, 2002 between

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CUBIST and IHMA ("the SRA"), in conducting further research which concerns
application of the '360 Patent to develop oral delivery of ceftriaxone.

         D. The parties acknowledge that the license between IHMA and CUBIST,
and the license between the UNIVERSITY and CUBIST and the sublicense between
CUBIST and IHMA, when such sublicense has been executed, entitle CUBIST and IHMA
to grant licenses or sublicenses of rights under the '360 Patent as follows:

         1. IHMA may solicit, negotiate and enter into exclusive license(s) with
         any other person(s), which grant it/them the right to make, have made,
         import, use, offer to sell and sell any product or method that, but for
         the existence of a license, would constitute infringement of the '360
         Patent with respect to oral formulations, or methods related to oral
         formulations, of cefditoren and cefepime, or either of those
         pharmaceuticals.

         2. IHMA may solicit, negotiate and enter into non-exclusive license(s)
         with any other person(s), which grant it/them the right to research,
         develop, make, have made, import, use, lease and sell any product or
         method that, but for the existence of a license, would constitute
         infringement of the '360 Patent with respect to oral formulations, or
         methods related to oral formulations, of any pharmaceutical products
         except ceftriaxone.

         3. CUBIST may solicit, negotiate and enter into non-exclusive
         license(s) with any other person(s) which grant it/them the right to
         make, have made, import, use, offer to sell and sell any product or
         method that, but for the existence of a license, would constitute
         infringement of the '360 Patent with respect to oral formulations, or
         methods related to oral formulations, of any pharmaceutical products.

         4. CUBIST may solicit, negotiate and enter into exclusive or
         non-exclusive license(s) with any other person(s) which grant it/them
         the right to research, develop,

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         make, have made, import, use, lease and sell any product or method
         that, but for the existence of a license, would constitute infringement
         of the '360 Patent with respect to oral formulations, or methods
         related to oral formulations, of ceftriaxone.

E. Insofar as IHMA or CUBIST, or both of them, desires to secure the right to
enter into an exclusive license with any other person(s) which grant it/them the
right to use the '360 Patent and related technology in developing and practicing
oral delivery of any pharmaceutical besides ceftriaxone, cefipime and
cefditoren, then IHMA and CUBIST will negotiate between them for the purpose of
defining the licensing fees and royalties which shall be paid by such person,
the manner in which those licensing fees and royalties shall be shared between
IHMA and CUBIST, and the particular pharmaceutical to which such exclusive
license shall be limited. It is understood that the rights of the UNIVERSITY to
receive licensing fees and royalties arise under its license to CUBIST, and
CUBIST shall have sole responsibility to pay such licensing fees and royalties
out of such portion of the licensing fees and royalties as IHMA and CUBIST agree
shall be received by CUBIST.

4.       PATENT PROSECUTION AND MAINTENANCE

         The following provisions shall be deemed to supercede Article 2.4 of
the License Agreement: IHMA, using mutually acceptable patent counsel, shall
prosecute and maintain patents and patent applications on IHMA Technology in
the United States and up to twenty-five (25) foreign countries selected by
CUBIST. IHMA shall furnish or have furnished to CUBIST copies of documents
relevant to patent applications, and maintenance of patent applications, and
IHMA shall confer with CUBIST regarding any patent application applicable to
IHMA Technology

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licensed to CUBIST in the License Agreement, so that each such patent
application may be satisfactory to IHMA and to CUBIST. Any differences between
IHMA and CUBIST with respect to filing, prosecution and maintenance of patents
covered by the License Agreement will be discussed and resolved to their mutual
satisfaction.

         IHMA shall be responsible for all expenses associated with the filing,
prosecution, issuance and maintenance of patents applying IHMA Technology
licensed to CUBIST in the License Agreement in the United States and up to
twenty-five (25) foreign countries selected by CUBIST in the Territory. At the
request of CUBIST, IHMA shall provide written evidence that it has performed
this obligation. CUBIST shall be responsible for all expenses associated with
the preparation, filing and maintenance of patents for IHMA Technology licensed
to CUBIST in the License Agreement in such additional countries as CUBIST may
direct, and shall reimburse IHMA for all such expenses. IHMA shall provide
CUBIST with detailed invoices for all reimbursable patent expenses for
additional countries, which CUBIST shall pay directly or reimburse to IHMA,
within thirty (30) days following receipt of invoices,

IN WITNESS WHEREOF, the parties hereto have caused this Addendum to be executed
by their respective officers, who are each authorized to sign on behalf of his
respective corporation, and have duly delivered and executed this Addendum to be
effective on September 27, 2002, intending it to be an instrument under seal.

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INTERNATIONAL HEALTH MANAGEMENT ASSOCIATES, INC.

By: /s/ STEVEN W. BLUTH
   ------------------------------------
Name:    Steven W. Bluth
Title:   Vice President

Date:    27 FEB -3
     ----------------------------------

CUBIST PHARMACEUTICALS, INC.

By: /s/ OLIVER S. FETZER
   ------------------------------------
Name:    Oliver S. Fetzer
Title:   Senior Vice President

Date:    2/28/03
     ----------------------------------

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                                                                EXHIBIT 10.60

                                           January 20, 2003

BY HAND DELIVERY

Michael W. Bonney
President & COO
Cubist Pharmaceuticals, Inc.
65 Hayden Avenue
Lexington, MA 02421

     RE: RETENTION LETTER

Dear Mike:

     You are a highly valuable employee of Cubist Pharmaceuticals, Inc.
("Cubist"). Cubist wishes to retain you as an employee, and is therefore willing
to make certain commitments in order to induce you to remain an employee. This
letter will confirm the agreement between you and Cubist ("Agreement") in that
regard. The Agreement is as follows:

     1.   DEFINITIONS. For the purposes of this Agreement, the following
          definitions apply:

          (a)  "Cause" means: (i) you commit of an act of fraud or
               misrepresentation in connection with your employment; (ii) you
               are convicted of, or plead nolo contendere to, a felony or a
               crime involving moral turpitude; (iii) you breach any material
               obligation under your Proprietary Information and Inventions
               Agreement; (iv) you engage in substantial or continuing
               inattention to or neglect of your duties and responsibilities
               reasonably assigned to you by Cubist; or (v) you engage in
               substantial or continuing acts to the detriment of Cubist or you
               engage in substantial or continuing acts inconsistent with
               Cubist's policies or practices.

          (b)  "Good Reason" means: (i) the failure of Cubist to employ you in
               your current or a substantially similar position such that your
               duties and responsibilities are materially diminished without
               your consent; (ii) a reduction in your aggregate base salary and
               potential bonus without your consent (unless such reduction is in
               connection with a proportional reduction in compensation to all
               or substantially all of Cubist's employees); or (iii) a
               relocation of your primary place of employment more than 20 miles
               from your current site of employment without your consent.

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          (c)  a "Change of Control" occurs: (i) when any person or entity other
               than Cubist or one of its subsidiaries becomes the owner of fifty
               percent (50%) or more of Cubist's common stock or (ii) upon the
               effective date of an agreement of acquisition, merger, or
               consolidation that has been approved by Cubist's stockholders and
               that contemplates that all or substantially all of the business
               and/or assets of Cubist shall be owned or otherwise controlled by
               another person or entity upon the effective date of such
               agreement.

     2.   SEVERANCE. In the event that your employment is terminated by Cubist
          for any reason other than for Cause, or by you for Good Reason, then,
          within five (5) days of the date of your termination, Cubist shall
          make a one-time, lump-sum payment to you equal to twelve (12) months
          of your then-current base salary.

     3.   WITHHOLDING. All payments made by Cubist under this Agreement shall be
          reduced by any tax or other amounts required to be withheld by Cubist
          under applicable law.

     4.   MEDICAL AND DENTAL BENEFITS. In the event that your employment is
          terminated by Cubist for any reason other than for Cause, or by you
          for Good Reason, then Cubist will maintain your medical and dental
          insurance coverage for a period of up to twelve (12) months after the
          month in which your employment terminates, provided that you pay the
          employee portion for such coverage by making a payment to Cubist
          during the first five (5) days of any month in which you elect to
          continue such coverage. Except for any right you have to continue
          participation in Cubist's group health and dental plans as provided
          herein or under the federal law known as "COBRA," all employee
          benefits shall terminate in accordance with the terms of the
          applicable benefit plans as of the date of termination of your
          employment.

     5.   ACCELERATION OF OPTIONS. In the event that, within twenty-four (24)
          months after a Change of Control, your employment is terminated either
          (i) by Cubist for any reason other than for Cause or (ii) by you for
          Good Reason, then all outstanding unvested stock options and/or
          restricted stock awards granted to you under any Cubist stock option
          plan prior to the Change of Control shall become exercisable and
          vested in full, and all restrictions thereon shall lapse,
          notwithstanding any vesting schedule or other provisions to the
          contrary in the agreements evidencing such options or awards, and
          Cubist and you hereby agree that such stock option agreements and
          restricted stock awards are hereby, and will be deemed to be, amended
          to give effect to this provision.

     6.   NO CONTRACT OF EMPLOYMENT. This Agreement is not a contract of
          employment for a specific term, and your employment is "At Will" and
          may be terminated by Cubist at any time.

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     7.   EMPLOYEE RELEASE. Any obligation of Cubist to provide you severance
          payments or other benefits under this Agreement is expressly
          conditioned upon your reviewing and signing (and not revoking during
          any applicable revocation period) a general release of claims in a
          form reasonably satisfactory to Cubist. Cubist shall provide you with
          the general release promptly after the date on which you give or
          receive, as the case may be, notice of termination of your employment.

     8.   ASSIGNMENT. You shall not make any assignment of this Agreement or any
          interest in it, by operation of law or otherwise, without the prior
          written consent of Cubist. Cubist may assign its rights and
          obligations under this Agreement without your consent. This Agreement
          shall inure to the benefit of and be binding upon you and Cubist, and
          each of our respective successors, executors, administrators, heirs
          and permitted assigns.

     9.   SEVERABILITY. If any portion or provision of this Agreement shall to
          any extent be declared illegal or unenforceable by a court of
          competent jurisdiction, then the remainder of this Agreement, or the
          application of such portion or provision in circumstances other than
          those as to which it is so declared illegal or unenforceable, shall
          not be affected thereby, and each portion and provision hereof shall
          be valid and enforceable to the fullest extent permitted by law.

     10.  MISCELLANEOUS. This Agreement sets forth the entire agreement between
          you and Cubist in connection with the subject matter hereof, and
          replaces all prior and contemporaneous communications, agreements and
          understandings, written or oral, with respect to the subject matter
          hereof with the exception of your obligations set forth in your
          Proprietary Information and Inventions Agreement with Cubist, which
          obligations shall remain in full force and effect. In consideration of
          the benefits provided to you hereunder, you agree that, in the event
          of your termination from Cubist, such benefits shall be in complete
          satisfaction of any and all obligations that Cubist may have to you.
          This Agreement may not be modified or amended, and no breach shall be
          deemed to be waived, unless agreed to in writing by you and an
          expressly authorized representative of Cubist. This Agreement may be
          executed in two counterparts, each of which shall be an original and
          all of which together shall constitute one and the same instrument.
          This Agreement shall be governed by the laws of the Commonwealth of
          Massachusetts, without regard to its conflicts of laws principles, and
          all disputes hereunder shall be adjudicated in the courts of the
          Commonwealth of Massachusetts, to whose personal jurisdiction you
          hereby consent.

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If the foregoing is acceptable to you, please sign both copies of this letter in
the space provided, at which time this letter will take effect as a binding
agreement between you and Cubist. Please keep one original for your records and
return one original to me.

                                        Cubist Pharmaceuticals, Inc.

                                        By: /s/ Scott M. Rocklage
                                            ------------------------------------
                                                Scott M. Rocklage, Ph.D.
                                                Chairman and CEO

Accepted and Agreed:

By: /s/ Michael W. Bonney
    ----------------------------------
Name: Michael W. Bonney
Date:

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