Exhibit 10.52

AMENDMENT NO. 2 TO CREDIT AGREEMENT

                THIS AMENDMENT NO. 2 (this “Amendment”) dated as of December 31,
2004 to the CREDIT AGREEMENT dated March 12, 2003, as amended by the Amendment
No. 1 to Credit Agreement dated December 31, 2003 (collectively, the “Credit
Agreement”), is by and among ARIAD Pharmaceuticals, Inc., a Delaware
corporation, ARIAD Corporation, a Delaware corporation, and ARIAD Gene
Therapeutics, Inc., a Delaware corporation (hereinafter sometimes referred to
collectively as the “Borrowers”) and Citizens Bank of Massachusetts, a
Massachusetts bank (the “Lender”). All capitalized terms not defined herein but
defined in the Credit Agreement shall have the meanings given to such terms in
the Credit Agreement.

                WHEREAS, the Borrowers and the Lender have agreed to certain
modifications to the Credit Agreement as set forth herein.

                NOW, THEREFORE, in consideration of the mutual promises and
covenants set forth herein, the Borrowers and the Lender hereby agree that the
Credit Agreement is amended as follows:

                1.      Amendment to Subsection 2.1(a).   Subsection 2.1(a) of
the Credit Agreement is hereby deleted in its entirety and replaced with the
following:

                         2.1  General.

 

                      (a) Subject to the terms and conditions hereof, the Lender
agrees to make a loan (the “Loan”) to the Borrowers on the Closing Date in the
principal amount of Nine Million Five Hundred Seventy-Five Thousand and 00/100
Dollars ($9,575,000.00). The principal amount of the Loan may from time to time
be advanced as or converted to (i) LIBOR Loans, (ii) Prime Rate Loans or (iii) a
combination thereof, as determined by the Borrowers and notified to the Lender
in accordance with subsections 2.2 and 2.8.

 

                             2.              Amendment to Subsection 2.5.
  Subsection 2.5 of the Credit Agreement is hereby deleted in its entirety and
replaced with the following:

 

                           2.5           Payment of Term Loan.   The Borrowers
hereby unconditionally promise to pay to the order of the Lender the principal
amount of the Loan in thirty-eight monthly installments of One Hundred
Sixty Thousand and 00/100 Dollars ($160,000.00) commencing on January 31, 2005,
and continuing on the last day of each consecutive month thereafter until the
Maturity Date. The Borrowers hereby further agree to pay interest on the unpaid
principal balance of the Loan, in arrears, on each Interest Payment Date;
provided, however, any such interest accruing at the Late Rate shall be due and
payable on demand. On the Maturity Date (or such earlier date on which the Loan
becomes due and payable pursuant to subsection 7.1), the entire remaining
outstanding balance of the Loan (including, without limitation, all unpaid
principal, all accrued but unpaid interest and all unpaid fees, charges, costs
and expenses) shall be immediately due and payable in full.

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                 3.         Amendment to Subsection 5.11.   Subsection 5.11 of
the Credit Agreement is hereby amended by adding the following paragraph to the
end of said Subsection 5.11:

 

                   Notwithstanding the foregoing, the Lender hereby waives the
foregoing requirements of this subsection 5.11 in connection with the formation
of the Foreign Subsidiary known as ARIAD Pharma S.A. provided the Borrowers
remain in compliance with the following requirements:                      (a)
The initial capitalization of ARIAD Pharma S.A. shall not exceed 60,000 euros.  
                   (b) The Borrowers shall not advance more than 25,000 euros
per year to fund the operations of ARIAD Pharma S.A.

 

                 4.         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
Thirteen Million and 00/100 Dollars ($13,000,000.00) 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 Citizens Investment Management Services, a unit of the Lender
which provides financial management services (“CIMS”) or the Treasury Desk, 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.                      (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.

 

               5.              Amendment to Appendix A to the Credit Agreement.
The text of each of the following definitions contained in Appendix A of the
Credit Agreement is hereby deleted in its entirety and replaced with the
following:

                                “Closing Date”:  the date on which the
conditions precedent set forth in Section 3 shall be satisfied or waived, except
that with respect to Amendment No. 2 to Credit Agreement

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dated December 31, 2004 and the Second Amended and Restated Term Note delivered
in connection therewith, the Closing Date shall be December 31, 2004.

                             “Interest Payment Date”:

 

                   (a)           as for any Prime Rate Loans, the last day of
each calendar month, commencing in January, 2005;                     
(b)           as for any LIBOR Loan having an Interest Period of three (3)
months or less, the last day of such Interest Period; and                     
(c)           as for any LIBOR Loan having an Interest Period longer than three
months, each day which is three (3) months, or a whole multiple thereof, after
the first day of such Interest Period and the last day of such Interest Period.

 

                             “Maturity Date”: March 31, 2008.

                 6.          Amendment to Appendix A to Exhibit B to the Credit
Agreement.   Appendix A to Exhibit B of the Credit Agreement is hereby deleted
in its entirety and replaced with the attached Appendix A.

                 7.          Amendment to Subsection 6.10.    Subsection 6.10 of
the Credit Agreement is hereby amended by adding the following Subsection
6.10(d) thereto:

                                (d) the initial capitalization of ARIAD Pharma
S.A. in an amount not to exceed 60,000 euros and loans, extensions of credit,
capital contributions, advances and other forms of investment of up to, but not
exceeding, 25,000 euros per year to ARIAD Pharma S.A. to fund operations.

                 8.          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.

                 9           Credit Extension and Amendment Fee.   The Borrowers
hereby agree to pay to the Lender a fee of $7,500.00 in consideration of the
Lender entering into this Amendment.

                 10.        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.

                11.        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

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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).

                12.           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.

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

                 14.           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.

                 15.           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.

 

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 and                             Chief Financial Officer          
ARIAD CORPORATION           By:  /s/  Edward M. Fitzgerald     —————————————————
          Name:       Edward M. Fitzgerald           Title:         Vice
President and                             Chief Financial Officer

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  ARIAD GENE THERAPEUTICS, INC.           By:   /s/  Harvey J. Berger    
————————————————           Name:       Harvey J. Berger, M.D.  
        Title:         Chief Executive Officer         WITNESS AS TO LENDER:
CITIZENS BANK OF MASSACHUSETTS         /s/  David P. O’Connell By: /s/  R. Scott
Haskell —————————————   ———————————————— Name:         R. Scott Haskell, Vice
President

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EXHIBIT D

ARIAD Pharmaceuticals, Inc.
Statement of Investment Policy for the Company’s Short-Term Investment Portfolio
Approved by the ARIAD Board of Directors on December 16, 2003

PURPOSE:

To establish a policy for the regular investment of surplus Company funds which
are not needed to meet current operating cash requirements.

POLICY OBJECTIVES:

The primary objective of this Investment Policy is to establish guidelines to
govern the management of the Company’s short-term investment portfolio
consistent with the following objectives:

1)      Preserve capital
2)      Maintain liquidity to meet Company operating cash flow requirements
3)      Maximize return, subject to these investment guidelines and the
Company’s tax situation

RESPONSIBILITIES:

It is the responsibility of the Board of Directors to adopt this policy. The
Chief Executive Officer or Chief Financial Officer shall have responsibility to
implement this Policy, shall monitor compliance both internally and by outside
money managers, and shall be the only officers authorized to make deposits into
or withdrawals from the Company’s short-term investment accounts. The Chief
Executive Officer or Chief Financial Officer may delegate day-to-day transaction
initiation within the Company short-term investment portfolio to the Corporate
Controller.

POLICY APPLICABILITY:

This Investment Policy applies to the total of all Company short-term
investments, including all sums held as investable cash, money market accounts,
money market funds, and short-term marketable securities. This Investment Policy
does not apply to cash held in operating accounts or maintained as compensating
balances for credit facilities.

INVESTMENT GUIDELINES:

General

The Company’s short-term investment portfolio should be structured to match the
needs of the Company’s current financial situation. In managing and structuring
its short-term investment portfolio, management will consider the projections of
operating cash flow, updated periodically, and ensure liquidity requirements are
satisfied. Potential liquidity requirements must be considered to minimize
unnecessary early liquidation of investments or borrowing. The trade-off between
liquidity and yield must be carefully considered when structuring the portfolio.

Maturity

Maturities of individual investments shall not exceed 36 months from the date of
trade settlement.

Liquidity

The Company’s short-term investment portfolio shall consist of money market
funds and liquid securities that regularly trade in a secondary market under
normal conditions. The portfolio shall be structured so that securities mature
as needed to meet anticipated Company operating cash flow and liquidity needs.

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Credit Quality

No investment may be rated lower than the minimum credit rating of A for bonds,
A1/P1 for commercial paper, and MIG- l/SP-1 for municipal securities.

Currency

All investments must be denominated in US dollars, Eurodollars or hedged back to
US dollars. The only non-US dollar investments held will be the result of
specific hedging caused by foreign exchange exposure.

Safety

Investments will be made in the highest quality instruments to ensure the safety
of the investments. Each instrument must meet minimum credit ratings outlined in
this policy.

Diversification
                                                                                                                               

 

• No single security in the portfolio may be larger than the greater of $5
million or 5% of the total investment portfolio (excluding investments in
obligations of the US government and its agencies, money market accounts with
immediate liquidity, diversified money market funds, and time deposits with
approved banks).   • Time deposits of approved banks may be purchased with
maturities of 90 days or less and are subject to the limits shown below.
Approved banks consist of the largest 200 banks as ranked by assets with rating
of A or better.  

• AAA Bank:                               $5 million • AA
Bank:                                  $3 million • A
Bank:                                     $1 million  

• No single municipal security may exceed $2 million   • Securities over 1 year
in maturity must be rated AA or better   • No single institution rated less than
AAA (other than the US government or its agencies) may back or guarantee more
than $5 million of the total investment portfolio   • Institutional money market
funds and bond funds must b managed by major bank trust department portfolio
managers, major brokerage houses, or major institutional fund advisor.

 

Allowable Instruments

The following are the only types of securities authorized for investment:

 

• US Treasury securities   • Federal agency securities   • Corporate securities,
including commercial paper, corporate bonds, medium-term notes, variable rate
demand obligations, tender option bonds, and similar instruments   • Diversified
money market funds with daily liquidity option or money market accounts with
immediate liquidity   • Banker’s acceptances, certificates of deposit, time
deposits of approved institutions   • Auction rate securities   • Municipal
securities, including revenue, tax, general obligation, and similar instruments
  • Asset-backed securities which are senior and collateralized by either credit
card receivables or auto loans

 

Downgrade Policy

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Any security with over six months remaining to maturity that drops to A or below
will require the Chief Executive Officer’s or Chief Financial Officer’s approval
to continue to hold in the portfolio.

Securities or investments that no longer meet the criteria of this policy should
be sold or exchanged when market conditions permit realization of reasonable
value.

Exceptions

In limited or unusual circumstances, only the Chief Executive Officer or the
Chief Financial Officer may approve exceptions to this policy.

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EXHIBIT E

[ARIAD Pharmaceuticals, Inc. Letterhead]

Date

Mr. Scott Haskell
Mr. William Clossey
Technology Banking Division
Citizens Bank
53 State St. MBS830
Boston, MA 02110

1.     Re:  Treasury Investment Instructions

Dear Scott & Will:

[Provide investment instructions]

Warranty & Representation:

ARIAD Pharmaceuticals, Inc. (“ARIAD”) hereby warrants and represents that it
will remain in compliance with all of ARIAD’s covenants in the Credit Agreement
dated March 12, 2003, as amended (the “Credit Agreement”) between Citizens Bank
of Massachusetts and ARIAD, and no Event of Default exists or will exist under
the Credit Agreement, after execution of the above mentioned investment
instructions.

Sincerely,
[ARIAD officer signature]

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CREDIT AGREEMENT
(the “Agreement”)

by and between

CITIZENS BANK OF MASSACHUSETTS
(the “Lender”)

and

ARIAD PHARMACEUTICALS, INC.,
ARIAD CORPORATION and ARIAD GENE THERAPEUTICS, INC.
(each individually, a “Borrower” and collectively, the “Borrowers”)

MASTER DISCLOSURE SCHEDULE

                 The Borrowers, jointly and severally, represent and warrant to
the Lender that the statements contained in Section 4 of the Agreement are true,
correct and complete as of the date of the Agreement, except as set forth in
this Master Disclosure Schedule (as the same may be supplemented, from time to
time, the “Master Disclosure Schedule”). The Master Disclosure Schedule is
arranged in sections corresponding to the lettered and numbered sections
contained in Section 4 of the Agreement.

 

4.6 No exceptions except ongoing litigation as a plaintiff against Eli Lilly and
Company as described in ARIAD Pharmaceuticals, Inc.’s Form 10-Q for the fiscal
quarter ended June 30, 2004, filed on August 4, 2004.     4.15 ARIAD
Pharmaceuticals, Inc. has the following subsidiaries:    

                                                 ARIAD Corporation (100% owned)
                                                 ARIAD Gene Therapeutics, Inc.
(80% owned)
                                                 ARIAD Pharma S.A. (99% owned)

 

                ARIAD Corporation has the following subsidiaries:  
                                   ARIAD Pharma S.A. (1% owned)  
                ARIAD Gene Therapeutics, Inc. has no subsidiaries.

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Appendix A to Compliance Certificate
ARIAD Pharmaceuticals, Inc.
ARIAD Corporation
ARIAD Gene Therapeutics, Inc.  

I. Total Balance Sheet Cash & Investments:            1. Total Cash &
Investments:

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         2. Required Total Cash & Investments Per Covenant: $13,000,000  

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         3. Excess / (Deficit) (#1-#2)

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        II. Citizens Treasury Investments:            4. Borrowers’ Treasury
Investments:

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         5. Required Treasury Investments (#1*85%)#:

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         6. Minus Excess Investments (#1-$17MM*85%)##:

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         7. Adjusted Required Treasury Investments (#5-#6):

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         8. Excess / (Deficit) Treasury Investments (#4-#7):

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    III. Treasury Investment Summary:            Government Securities:

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         Commercial Paper:

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         Citizens Certificate of Deposits:

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         Treasury Bills:

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         Total (Equals #4):

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#     Per Section 5.13(b) Paragraph 1.   ##  Per Section 5.13(b) Paragraph 2.  

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