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                                                                   EXHIBIT 10.59
                            STOCK ISSUANCE AGREEMENT

      THIS STOCK ISSUANCE AGREEMENT (the "Agreement") is entered into and made
effective as of January 13, 2004 (the "Effective Date"), between ARIAD Gene
Therapeutics, Inc., a Delaware corporation ("AGTI"), and ARIAD Pharmaceuticals,
Inc., a Delaware corporation ("ARIAD").

      WHEREAS, ARIAD formed AGTI in 1993 as a controlled subsidiary;

      WHEREAS, upon formation of AGTI, ARIAD and AGTI entered into various
agreements to provide for the operations of AGTI, which agreements were amended
and restated in January 2002 (collectively, the "Intercompany Agreements");

      WHEREAS, pursuant to the Intercompany Agreements, ARIAD has provided
capital and services to AGTI in exchange for its controlling interest, service
fees and other consideration;

      WHEREAS, as of the Effective Date, AGTI has accumulated an account payable
to ARIAD of approximately $78 million pursuant to the Intercompany Agreements;

      WHEREAS, AGTI currently has outstanding stock options to purchase up to
87,428 shares of common stock of AGTI (the "AGTI Options"), which AGTI Options
will either be exercised in whole or in part or expire on or before January 17,
2003;

      WHEREAS, the disinterested members of the Board of Directors of ARIAD and
the members of the AGTI Board have each determined it to be in the best
interests of their respective shareholders for AGTI to authorize and issue up to
351,909 shares of common stock of AGTI to ARIAD in exchange for a capital
contribution by ARIAD to AGTI equal to the fair market value of such shares and
the form of cancellation of a portion of AGTI's account payable to ARIAD
pursuant to the Intercompany Agreements, such transactions to occur prior to
exercise of the AGTI Options in order to maintain ARIAD's controlling interest
in AGTI; and
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      WHEREAS, ARIAD, as the controlling shareholder of AGTI, has approved the
authorization and issuance by AGTI to such shares pursuant to the terms and
conditions of this Agreement.

      NOW, THEREFORE, for good consideration, the receipt and sufficiency of
which is hereby acknowledged, the parties hereby agree as follows:

      1. Issuance of AGTI Common Stock.

            1.1 Capital Contribution and Issuance of Shares. In consideration of
the terms and conditions of this Agreement, AGTI agrees to authorize and issue
to ARIAD Three Hundred Fifty One Thousand, Nine Hundred Nine (351,909) shares of
AGTI's Common Stock. $.001 par value per share ("Shares"), in exchange for a
capital contribution by ARIAD to AGTI of $25.00 per Share, for an aggregate
capital contribution of Eight Million, Seven Hundred Ninety-Seven Thousand,
Seven Hundred Twenty-Five Dollars ($8,797,725), which contribution amount is
subject to adjustment as set forth in Section 1.3 below (the "Capital
Contribution").

            1.2 Issuance of Shares By, and Credit to Accounts Payable of, AGTI.
The issuance of the Shares shall take place at the offices of ARIAD on a date
not later than January 16, 2004 upon which the parties shall mutually agree. On
such date, (i) indebtedness in an amount equal to the Capital Contribution shall
be cancelled by ARIAD by debiting AGTI's account payable to ARIAD on the books
and records of AGTI and crediting the corresponding account receivable on the
books and records of ARIAD, and (ii) AGTI shall issue to ARIAD a stock
certificate evidencing the Shares. In the event that a subsequent adjustment is
made to the Capital Contribution pursuant to Section 1.3 below, as soon as
practicable but no later than December 31, 2004, ARIAD shall make a
corresponding adjustment by crediting or debiting, as the case may be, the
amount of ARIAD's account receivable from AGTI on its books and records and AGTI
shall make a corresponding adjustment by debiting or crediting, as the case may
be, AGTI's account payable to ARIAD on its books and records.

            1.3 Adjustment to Capital Contribution. The parties acknowledge and
agree that the Capital Contribution set forth in Section 1.1 of this Agreement
is based on a good-faith determination by the Board of Directors of AGTI and the
disinterested members of the Board of Directors of ARIAD (collectively, the
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"Directors") of the fair market value of the Shares as of the Effective Date
hereof using a valuation methodology which is consistent with past practice and
comparable transactions. If either or both parties desires to retain the
services of an independent valuation expert to determine the fair market value
of AGTI, the parties shall confer and shall designate one mutually agreeable
expert who shall be retained by both parties on or before November 1, 2004 (to
allow sufficient time to conduct such valuation prior to the closing of the
consolidated books and records of ARIAD and AGTI on December 31, 2004) to review
and provide its expert opinion on or before December 31, 2004 (the "Adjustment
Date") as to the valuation of the Shares as of the Effective Date (the "Expert
Valuation"). If the parties fail to agree on the selection of the valuation
expert after good-faith discussion, the selection of the valuation expert shall
be made as soon as practicable by an arbitrator chosen pursuant to Section 2.3
hereof. The cost of such Expert Valuation shall be borne equally by the parties
hereto. In the event that the Expert Valuation of the per Share price as of the
Effective Date differs from per Share price set forth in Section 1.1 hereof, an
adjustment reflecting such variance in the Capital Contribution shall be made on
the books and records of ARIAD and AGTI as set forth in Section 1.2 hereof. As
between ARIAD and AGTI, they agree that the Expert Valuation shall be conclusive
for purposes of such adjustment. Alternatively, in the absence of an Expert
Valuation, if the Directors make a good faith determination on or before
December 31, 2004, based on all of the facts and circumstances which hereafter
become known to them, that an adjustment to the per Share price as of the
Effective Date is warranted, 2004, such adjustment shall be reflected in the
amount of Capital Contribution credited against ARIAD's account receivable from
AGTI and debited against AGTI's accounts payable to ARIAD on the books and
records of each respective company as of December 31, 2004 for solely for
purposes of Section 1.2 hereof, which amount of Capital Contribution as so
adjusted shall be deemed conclusive for purposes of this Agreement.
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      2. Miscellaneous.

            2.1 Entire Agreement.This Agreement contains the entire
understanding of the parties with respect to the matters covered hereby. No
provision of this Agreement may be waived or amended other than by a written
instrument signed by the party against whom enforcement of such waiver or
amendment is sought.

            2.2 Governing Law. This Agreement shall be governed and construed in
accordance with the laws of the State of Delaware, without giving effect to
conflict of law principles.

            2.3 Binding Arbitration. Any dispute initiated by either party
arising out of, resulting from or relating to this Agreement, or the performance
by either Party of its obligations under this Agreement shall be finally
resolved by binding arbitration. Whenever a party shall decide to institute
arbitration proceedings, it shall give written notice to that effect to the
other party as provided in Section 2.4 hereof. Any such arbitration shall be
conducted under the Commercial Arbitration Rules of the American Arbitration
Association. If the amount in dispute involves less than US $5 million,
exclusive of interest and costs, then the arbitration shall be conducted and
finally settled by a sole arbitrator. If the amount in controversy, exclusive of
interest and costs, is US $5 million or more, if the amount in dispute is
unknown, or if relief other than damages is sought, then the arbitration shall
be conducted and finally settled by three (3) arbitrators. If the arbitration is
to be conducted by a sole arbitrator, then the arbitrator will be jointly
selected by the parties. If the parties fail to agree on the arbitrator within
forty-five (45) days after the initiation of the arbitration, then the American
Arbitration Association shall appoint the arbitrator. If the arbitration is to
be conducted by three (3) arbitrators, each party shall select one arbitrator,
and these two arbitrators shall select the third arbitrator. If the two
party-appointed arbitrators fail to agree on the third arbitrator within
forty-five (45) days after the appointment of the later of the two, then the
third arbitrator shall be appointed by the American Arbitration Association. In
all cases, the arbitrator(s) shall have relevant expertise and recent experience
in arbitrating matters pertinent to the biopharmaceutical industry and the
arbitration proceedings shall be held in Boston, Massachusetts. The method and
manner of discovery in any such arbitration proceeding shall be governed by the
laws of the Commonwealth of Massachusetts. The arbitrators shall have the
authority to grant remedies at law or in equity, including specific performance,
opportunity to cure and allocation of the costs of arbitration between the
parties in an
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equitable manner. Judgment upon the award so rendered may be entered in any
court having jurisdiction or application may be made to such court for judicial
acceptance of any award and an order of enforcement, as the case may be. In no
event shall a demand for arbitration be made after the date when institution of
a legal or equitable proceeding based upon such claim, dispute or other matter
in question would be barred by the applicable statute of limitations.

            2.4 Notices. Any notice, demand, request, waiver or other
communication required or permitted to be given hereunder shall be in writing
and shall be effective if delivered to ARIAD or AGTI, as the case may be, in the
manner set forth below to the address or number set forth below, in each case in
each case (a) upon hand delivery or by facsimile (if delivered on a business day
during normal business hours where such notice is to be received), or the first
business day following such delivery (if delivered other than on a business day
during normal business hours where such notice is to be received) or (b) on the
second business day following the date of mailing by express courier service,
fully prepaid, addressed to such address, or upon actual receipt of such
mailing, whichever shall first occur. The addresses for such communications
shall be:

            To ARIAD or to AGTI:

                ARIAD Pharmaceuticals, Inc.
                26 Landsdowne Street
                Cambridge, MA  02139
                Tel:  (617) 494-0400
                Fax: (617) 225-2860 (fax)
                Attn: Chief Legal Officer

            With a copy to:

                Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.
                One Financial Center
                Boston, MA  02111
                Tel: (617) 542-6000
                Fax:  (617) 542-2241 (fax)
                Attn: Jeffrey M. Wiesen, Esq.
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            2.5 Counterparts. This Agreement may be executed in one or more
counterparts, all of which taken together shall constitute one and the same
instrument.


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            IN WITNESS WHEREOF, the parties hereto have caused this Agreement to
by duly executed by their respective authorized representatives as of the date
first written above.

                                    ARIAD GENE THERAPEUTICS, INC.


                                    By:  /s/ Harvey J. Berger, M.D.
                                         ---------------------------------------
                                         Harvey J. Berger, M.D.
                                         Chairman and Chief Executive Officer




                                    ARIAD PHARMACEUTICALS, INC.



                                    By:  /s/ Edward M. Fitzgerald
                                         ---------------------------------------
                                         Edward M. Fitzgerald
                                         Chief Financial Officer