SECOND AMENDED AND RESTATED TERM NOTE

Exhibit 10.53

SECOND AMENDED AND RESTATED TERM NOTE

                 FOR VALUE RECEIVED, the undersigned, 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 each singly as a Borrower”), HEREBY UNCONDITIONALLY PROMISES TO PAY TO THE ORDER OF CITIZENS BANK OF MASSACHUSETTS, a Massachusetts bank (the “Lender”) at the office of the Lender, located at 28 State Street, Boston, Massachusetts 02109 (or such other place as the holder hereof may specify in writing), in lawful money of the United States of America and in immediately available funds, the principal amount of NINE MILLION FIVE HUNDRED SEVENTY-FIVE THOUSAND AND 00/100 DOLLARS ($9,575,000.00) (the “Loan”). The Borrowers jointly and severally agree to pay the principal amount of the Loan in the amounts and on the dates specified in subsection 2.5 of the Credit Agreement dated March 12, 2003, as amended by Amendment No. 1 to Credit Agreement, dated December 31, 2003, as further amended by Amendment No. 2 to Credit Agreement, dated December 31, 2004 (as the same may be further amended, modified, supplemented, extended or restated from time to time, the “Credit Agreement”) by and between the Lender and the Borrowers. The Borrowers further agree to pay interest on the unpaid principal balance of the Loan from time to time outstanding from the Closing Date until paid, at the rates and at the times provided in the Credit Agreement.

                 This Note is issued pursuant to the Credit Agreement, and the holder hereof is entitled to, and shall have, all of the benefits of the Credit Agreement, and all other agreements, instruments, guarantees and other documents executed and delivered in connection therewith and herewith. All capitalized terms not defined herein but defined in the Credit Agreement shall have the meanings given to such terms in the Credit Agreement.

                 This Note is secured as provided in the Security Documents. Reference is hereby made to the Security Documents for a description of the properties and assets in which a security interest has been granted, the nature and extent of the security, the terms and conditions upon which the security interests were granted and the rights of the holder of this Note in respect thereof.

                 Upon the occurrence and during the continuance of any one or more of the Events of Default, all amounts then remaining unpaid on this Note shall become, or may be declared to be, immediately due and payable, all as provided in the Credit Agreement.

                 All parties now and hereafter liable with respect to this Note, whether maker, principal, surety, guarantor, endorser or otherwise, hereby waive presentment, demand, protest and all other notices of any kind.

                 This Note shall be binding upon the Borrowers and their successors and assigns, and shall inure to the benefit of the Lender and its successors, assigns, endorsees and transferees.

                 All of the obligations and liabilities of the Borrowers under the Note are joint and several.

- 1 -