**Exhibit 10.54**

December 14, 2006

Robert I. Tepper

c/o Millennium Pharmaceuticals, Inc.

40 Landsdowne Street

Cambridge, MA 02139

Dear Dr. Tepper:

This letter amendsthe terms of your employment offer letter from Millennium Pharmaceuticals, Inc.(“Millennium” or the “Company”) dated May 5, 1994 (the “Letter Agreement”) andmemorializes certain other agreements between you and the Company.  Capitalized terms used herein and nototherwise defined shall have the meaning given to them in the Letter Agreement.

1.             Inconsideration of your agreement to remain employed by the Company as Presidentof R&D through March 31, 2007, or such earlier date as may be specified bythe Company’s Chief Executive Officer but in no event earlier than March 6,2007 (the “Termination Date”), you will receive: (a) the Severance Payment,provided, however, that the Severance Payment shall not be subject to reductionor cessation as provided in Section 7 of the Agreement, (b) a lump sum stayincentive payment equal to $225,000 (the “Incentive Payment”) and (c) providedthat you elect continued coverage under federal COBRA law, payment of theportion of premiums of your group health insurance coverage, including coveragefor your eligible dependents, that Millennium paid prior to the TerminationDate, for a period of 12 months following the Termination Date or the date onwhich you become eligible for substantially similar group benefits at asubsequent employer, whichever is earlier. The Severance Payment will be paid periodically in accordance with theCompany’s payroll procedures and the Incentive Payment will be paid to youwithin three days following the Termination Date.

2.             Infurther consideration of your agreement to remain employed by the Company, ifthe Termination Date occurs prior to the date on which payments are made underthe Company’s 2006 Success Sharing Bonus Program (the “2006 Program”), you willremain eligible to receive a bonus payment under the Program at the same timethat bonus payments are made to other participants in the program.  You acknowledge that you will not be eligiblefor any payment under the Company’s 2007 Success Sharing Bonus Program.

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Robert I. Tepper

December 14, 2006

Page 2

 

3.             The consideration provided for herein supersedes theconsideration provided for in Section 7 of the Letter Agreement and noadditional amounts shall be payable thereunder. All amounts that you receive from the Company hereunder will be subjectto all required tax withholding.  In theevent of a material breach of your continuing obligations to the Company,including under any Inventions, Non-Disclosure and Non-Competition Agreement(s)or similar agreements that you may have signed during your employment with theCompany, the Company reserves the right to cease the payments described herein.

4.             Inconsideration of receiving the payments outlined herein, you hereby release andforever discharge and hold Millennium, as well as its current and formersuccessors, employees, officers, directors, shareholders, parents,subsidiaries, affiliates and agents, harmless of all claims or suits of anynature whatsoever, including, but not limited to, any claims under federal,state and local laws that prohibit discrimination (including withoutlimitation, claims of discrimination based on race, age, religion, nationalorigin, sex, disability or handicap, and sexual orientation) and any claimswith respect to breach of contract (express and/or implied), wrongfultermination, Worker Adjustment and Retraining Notification Act and related state statute notificationobligations, the Older Workers Benefit Protection Act of 1990 and related statestatutes, intentional or negligent infliction of emotional distress,interference with contractual or advantageous business relations, loss ofconsortium, invasion of privacy, defamation, payment of wages, debts, costs andexpenses, attorneys’ fees and other damages, and any claims arising out of orin any way related to your employment with Millennium, which you now have, mayhave, or may have had from the beginning of time to the Termination Date.  Nothing in this paragraph shall be construedin any way to release Millennium from its obligation to indemnify you from anythird party action brought against you based on your employment with or serviceas an officer to Millennium pursuant to any applicable agreement or applicablelaw or to reduce or eliminate any coverage you may have under Millennium’sdirector and officer liability policies, if any.  As required by the Older Workers BenefitProtection Act of 1990, you acknowledge: (i) that you have been advised and given the opportunity to consultwith your own counsel prior to signing this Agreement; (ii) that you havebeen given 21 days from the receipt of this Agreement to consider whetherto sign it; (iii) that you have been advised that even after you sign thisAgreement, you may revoke it within 7 days of the date of your signing, bydelivering a signed revocation notice to Millennium’s Senior Vice-President ofHuman Resources; (iv) that this Agreement shall not become effective andin force until eight (8) days after you sign it, and (v) that you will notbe entitled to receive the payments described herein until after the 7-dayrevocation period has expired, and that, should you in fact revoke your acceptance,none of the payments outlined herein will be made.

5.             ThisAgreement may be amended or modified only by a written instrument executed byyou and Millennium.  This agreement willbe interpreted and enforced in

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Robert I. Tepper

December 14, 2006

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accordance with the lawsof the Commonwealth of Massachusetts.  Exceptas expressly stated in this letter, the Letter Agreement remains unchanged andin full force and effect.

*******Theremainder of this page is purposefully blank*******

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Robert I. Tepper

December 14, 2006

Page 4

 

Please acknowledgeyour agreement by countersigning this letter below.
|                 | Sincerely,                        |
|----------------------|-----------------------------------|
|                 |                              |
|                 | MILLENNIUM  PHARMACEUTICALS, INC. |
|                 |                              |
|                 | By:                               | /s/ STEPHEN  GANSLER |   |
|                 | Name:                             | Stephen Gansler |
|                 | Title:                            | SVP, Human Resources |
|                 |                              |
| AGREED TO:           |
|                 |
| /s/ ROBERT I. TEPPER |                              |
| Robert I. Tepper     |
|                      |                                   |  |  |  |  |

 

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