| 1.   | Lender      Identity.  All references in the Credit Agreement to      “Citizens Bank of Massachusetts” are hereby deleted and replaced with “RBS      Citizens, National Association”. |
|----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 2.   | Removal      of AGTI as a Co-Borrower.  AGTI is hereby deleted as a      co-borrower under the CreditAgreement. |
|----------------|---------------------------------------------------------------------------------------------------------------------------|

| 3.   | Amendment      to Subsection 5.13.  Subsection 5.13 of the Credit      Agreement is hereby deleted in its entirety and replaced with the      following: |
|----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 5.13 | Cash, Cash      Equivalents, Marketable Securities and  Investments. |
|------|----------------------------------------------------------------------|

|   | (a) | During      the term of this Agreement, the Borrowers shall maintain, as evidenced on      their consolidated balance sheet, not less than Fifteen Million and 00/100      Dollars ($15,000,000.00) in Unrestricted Cash, unrestricted Cash      Equivalents, and unrestricted marketable securities (the “Liquid      Assets”). |
|--------|-----|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | (b) | Not      less than Eighty-Five Percent (85%) of the Borrowers’ total Liquid Assets      shall be invested through and held by either the Treasury Desk or Citizens      Investment Management Services (“CIMS”), in      investments which are consistent with the Borrowers’ current investment      policy, a copy of which is attached hereto as Exhibit D, all      of such investments to be in book entry form (each singly, a “Treasury      Investment” and collectively, the “Treasury      Investments”).  Notwithstanding the foregoing, in no      event shall the Borrowers be required to invest more than Seventeen      Million and 00/100 Dollars ($17,000,000.00) with CIMS and the Treasury      Desk, collectively, during the Term of this Agreement.  In the      event the Borrowers intend to invest through the Treasury Desk, the      Borrower shall be required to enter into a control agreement in a form      acceptable to Borrower, Lender and the Treasury Desk prior to making any      investment with the Treasury Desk. |
|--------|-----|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

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|   | (c) | To      liquidate a Treasury Investment, the Borrowers shall, not less than two      (2) Business Days prior to the maturity of such Treasury Investments,      provide written instructions to the Lender via facsimile transmission      regarding such Treasury Investment in the form attached hereto as Exhibit E (the      "Treasury      Investment Instructions").  The Treasury Investment      Instructions shall contain, in addition to standard instructions, a      representation and warranty that the execution of the requested      instructions shall not cause a breach of any of the covenants contained in      this Agreement. |
|--------|-----|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 4.   | Amendment      to Appendix A to the Credit Agreement.  The text of the      definition of “Treasury Desk” contained in Appendix A of      the Credit Agreement is hereby deleted in its entirety and replaced with      the following: |
|----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | “Treasury      Desk”: CCO Investment ServicesCorp. |
|--------|----------------------------------------------------------------|

| 5.   | Amendment      to Appendix A to the Credit Agreement.  The text of      the definition of “Obligations” contained in Appendix A of the Credit      Agreement is hereby deleted in its entirety and replaced with the      following: |
|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | “Obligations”:  All      Indebtedness, obligations and liabilities of the Borrowers to the Lender      or its affiliates or subsidiaries, individually or collectively, now      existing or hereafter arising, direct or indirect, joint or several,      absolute or contingent, matured or unmatured, liquidated or unliquidated,      secured or unsecured, arising by contract, operation of law or      otherwise. |
|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 6.   | Amendment      to Appendix A to the Credit Agreement.  The term and      definition “Treasury Desk Investment” is hereby deleted and the following      term and definition are inserted in itsplace: |
|----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | “Treasury      Investment(s)” as defined in subsection  5.13(b). |
|--------|------------------------------------------------------------------------------|

| 7.   | Amendment      to Master Disclosure Schedule. The Master Disclosure      Schedule attached to the Credit Agreement is hereby deleted in its      entirety and replaced with the attached Master Disclosure      Schedule. |
|----------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 8.   | Waiver      of Non-Compliance by Borrower with Certain Provisions of Credit      Agreement.  Lender hereby waives compliance by the      Borrowers with the Two Hundred Fifty Thousand Dollar limitation on      Indebtedness contained in Section 6.2 for the sole purpose of permitting      the Borrowers to enter into new capital leases with Conway Office Products      L.L.C. and Dell Financial Services L.L.C. in the collective amount of up      to, but not exceeding, Six Hundred Thousand  Dollars. |
|----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 9.   | No      Further Amendments.  Except as amended hereby, all other      provisions of the Credit Agreement shall remain in full force and      effect.  After the effective date hereof, all references in the      Credit Agreement and other Financing Documents shall be deemed to refer to      the Credit Agreement as amended hereby, representing the entire expression      of the parties with respect to the subject matter hereof on the date this      Amendment is executed. |
|----------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 10.   | Ratification      of Financing Documents.  By signing      below, the Borrowers ratify and affirm the terms of the Credit Agreement      (as amended hereby), the Note, the Security Agreements and all other      Financing Documents executed in connection with any of the foregoing, and      confirm and represent that each remains in full force and effect and that      no default or event of default has occurred thereunder (except such      defaults or events of default as have been waived in writing by the Lender      on or before the date hereof or such defaults or events of default as the      Borrowers have requested, in writing prior to the date hereof, the Lender      to waive). |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

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| 11.   | Governing      Law.  This      Amendment shall be governed in all respects by the laws of the      Commonwealth of Massachusetts without regard to any conflicts of laws      principles. |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 12.   | Descriptive      Headings.  Descriptive      headings are for convenience only and will not control or affect the      meaning or construction of any provisions of this    Amendment. |
|-----------------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 13.   | Counterparts.  This      Amendment may be executed in any number of identical counterparts, each of      which will constitute an original but all of which when taken together      will constitute but one instrument. |
|-----------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

| 14.   | Severability.  In the      event one or more of the provisions of this Amendment should, for any      reason, be held to be invalid, illegal or unenforceable in any respect,      such invalidity, illegality, or unenforceability shall not affect any      other provisions of this Amendment, and this Amendment shall be construed      as if such invalid, illegal or unenforceable provision had never been      contained herein. |
|-----------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|

|   | WITNESS      our hands and seals as of the date set forth  above. |
|--------|-------------------------------------------------------------------|

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| WITNESS      AS TO BORROWERS:        |   | ARIAD      PHARMACEUTICALS, INC. |                                                                       |
|--------------------------------------|--------|----------------------------------|----------------------------------------------------------------------------|
|                                 |   |                             |                                                                       |   |
| /s/      Dain K. Waters              |   | By:                         | /s/      Edward M. Fitzgerald                                              |   |
| Name:  Dain      K. Waters |   |                             | Name:  Edward      M. Fitzgerald                                 |   |
|                                 |   |                             | Title:  Senior      Vice President, Chief Financial Officer |   |

|   |   | ARIAD      CORPORATION |                                       |
|--------|--------|------------------------|--------------------------------------------|
|   |   |                   |                                       |   |
|   |   | By:               | /s/      Edward M. Fitzgerald              |   |
|   |   |                   | Name:  Edward      M. Fitzgerald |   |
|   |   |                   | Title:  Vice      President      |   |

| WITNESS      AS TO LENDER: |   | RBS      CITIZENS, NATIONAL ASSOCIATION |
|----------------------------|--------|-----------------------------------------|
|                       |   |                                    |   |   |
|                       |   | By:                                | /s/      Scott Haskell |   |
| Name:                      |   |                                    | Scott      Haskell, Senior Vice President |   |
|                       |   |                                    |   |   |

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|   | 4.6    | No      exceptions except ongoing litigation as a plaintiff against Eli Lilly and      Company and against Amgen Inc. and certain affiliated entities as      described in ARIAD Pharmaceuticals, Inc.’s Form 10-Q for the fiscal      quarter ended September 30, 2007, filed on November 9,    2007. |
|--------|--------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
|   |   |                                                                                                                                                                                                                                                                                                         |
|   | 4.15   | ARIAD      Pharmaceuticals, Inc. has the followingsubsidiaries:                                                                                                                                                                                                                                              |

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| I.      Total Balance      Sheet Cash & Investments:          |        |
|-------------------------------------------------------------------|-------------|
| 1.      Total Cash & Investments:                             |        |
| 2.       Required Total Cash & Investments Per Covenant: | $15,000,000 |
| 3. Excess      / (Deficit) (#1-#2)                           |        |
|                                                              |        |
| II.Treasury      Investments:                                     |        |
| 3.      Borrower’s Treasury Investments:                    |        |
| 4.      Required Treasury Investments (#1*85%)#:                  |        |
| 5.      Minus Excess Investments (#1-$17MM*85%)##:                |        |
| 6. Adjusted      Treasury Investment Requirement (#4-#5):    |        |
| 7. Excess      / (Deficit) Treasury Investments (#3-#6):     |        |
|                                                              |        |
| III.Treasury      Investment Summary:                             |        |
| Government      Securities:                                       |        |
| Commercial      Paper:                                            |        |
| Citizens      Certificate of Deposits:                            |        |
| Treasury      Bills:                                              |        |
| Total      (Equals #3):                                           |        |

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