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                                                                    EXHIBIT 10.1

                         EXECUTIVE EMPLOYMENT AGREEMENT

EMPLOYMENT AGREEMENT (the "Agreement") made as of May 5, 2002 between ARIAD
Pharmaceuticals, Inc. (the "Company") a Delaware corporation, and Edward M.
Fitzgerald (the "Employee").

1.     EMPLOYMENT, DUTIES AND ACCEPTANCE.

       1.1    The Company hereby employs the Employee, for the Term (as
              hereinafter defined), to render full-time services to the Company,
              and to perform such duties as he shall reasonably be directed by
              the Chief Executive Officer of the Company to perform. The
              Employee's title shall be designated by the Chief Executive
              Officer and initially shall be Chief Financial Officer, Senior
              Vice President and Treasurer.

       1.2    The Employee hereby accepts such employment and agrees to render
              the services described above.

       1.3    The principal place of employment of the Employee hereunder shall
              be in the greater Boston, Massachusetts area, or other locations
              reasonably acceptable to the Employee. The Employee acknowledges
              that for limited periods of time he may be required to provide
              services to the Company outside of the Boston, Massachusetts area.

       1.4    Notwithstanding anything to the contrary herein, although the
              Employee shall provide services as a full-time employee, it is
              understood that the Employee may (a) have an academic appointment
              and (b) participate in professional activities (collectively,
              "Permitted Activities'); provided, however, that such Permitted
              Activities do not interfere with the Employee's duties to the
              Company.

2.     TERM OF EMPLOYMENT.

       The term of the Employee's employment under this Agreement (the "Term")
       shall commence on May 5, 2002 (the "Effective Date"), or such other date
       mutually agreed upon by the parties, and shall end on May 4, 2005, unless
       sooner terminated pursuant to Section 4 or 5 of this Agreement; provided
       that this Agreement shall automatically be renewed for successive
       one-year terms (the Term and, if the period of employment is so renewed,
       such additional period(s) of employment are collectively referred to
       herein as the "Term") unless terminated by written notice given by either
       party to the other at least ninety days prior to the end of the
       applicable Term. The parties agree to discuss in good faith by May 4,
       2004 extension of the Term.

3.     COMPENSATION.

       3.1    As full compensation for all services to be rendered pursuant to
              this Agreement, the Company agrees to pay the Employee, during the
              Term, a salary at the fixed rate of $220,000 per annum during the
              first year of the Term and increased each year thereafter, by
              amounts, if any, to be determined by the Board of Directors of the
              Company (the "Board"), in its sole discretion, payable in equal
              biweekly installments, less such deductions or amounts to be
              withheld as shall be required by applicable law and regulations.

       3.2    Each year, Employee shall be eligible to receive a discretionary
              bonus of up to 30% of base salary, which bonus shall be determined
              annually by the Board. The bonus, if any, may be

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              paid in the form of stock options, stock awards, deferred
              compensation or cash, as determined by the Board.

       3.3    The Company shall pay or reimburse the Employee for all reasonable
              expenses actually incurred or paid by him during the Term in the
              performance of his services under this Agreement, upon
              presentation of expense statements or vouchers or such other
              supporting information as it may require.

       3.4    The Employee shall be eligible under any incentive plan, stock
              award plan, bonus, deferred or extra compensation plan, pension,
              group health, disability and life insurance or other so-called
              "fringe" benefits which the Company provides for its executives at
              the comparable level. All stock options and stock awards granted
              to the Employee shall be subject to a vesting schedule which shall
              be determined by the Compensation Committee of the Board. The
              stock options and stock awards, if any, to be granted to the
              Employee shall also be subject to the terms of a stock option plan
              and certificate and stock award plan and certificate,
              respectively. Any unvested options shall be forfeited to the
              Company in the event (a) this Agreement is terminated by the
              Company for Cause pursuant to Section 4 herein, or (b) either
              party elects not to renew this Agreement pursuant to Section 2
              herein.

       3.5    The Company shall grant the Employee an option to purchase 100,000
              shares of the Company's Common Stock at the fair market value on
              the date of the Board's approval, in accordance with the Company's
              2001 Stock Plan, As Amended. The Employee agrees that all such
              options shall be subject to a four-year vesting schedule, vesting
              in equal increments of 25% on each anniversary of their issuance.
              Any unvested options shall be forfeited to the Company in the
              event (a) this Agreement is terminated by the Company for Cause
              pursuant to Section 4 herein, or (b) either party elects not to
              renew this Agreement pursuant to Section 2 herein.

4.     TERMINATION BY THE COMPANY.

       The Company may terminate this Agreement, if any one or more of the
following shall occur:

       (a)    The Employee shall die during the Term; provided, however, the
              Employee's legal representatives shall be entitled to receive the
              compensation provided for hereunder to the last day of the month
              in which his death occurs.

       (b)    The Employee shall become physically or mentally disabled, whether
              totally or partially, so that he is unable substantially to
              perform his services hereunder for (i) a period of 180 consecutive
              days, or (ii) for shorter periods aggregating 180 days during any
              twelve month period.

       (c)    The Employee acts, or fails to act, in a manner that provides
              Cause for termination. For purposes of this Agreement, the term
              "Cause" means (i) the failure by the Employee to perform any of
              his material duties hereunder, (ii) the conviction of the
              Employee of any felony involving moral turpitude, (iii) any acts
              of fraud or embezzlement by the Employee involving the Company or
              any of its Affiliates, (iv) violation of any federal, state or
              local law, or administrative regulation related to the business
              of the Company, (v) a conflict of interest, (vi) conduct that
              could result in publicity reflecting unfavorably on the Company
              in a material way, (vii) failure to comply with the written
              policies of the Company, or (viii) a breach of the terms of this
              Agreement by the Employee. The Company shall provide the Employee
              written notice of termination pursuant to this Section 4, and
              Employee shall have 30 days to cure or remedy such failure or
              breach, in which case this Agreement shall not be terminated.

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5.     TERMINATION BY THE EMPLOYEE.

       5.1    The Employee may terminate this Agreement, if any one or more of
              the following shall occur:

              (a)   a material breach of the terms of this Agreement by the
                    Company and such breach continues for 30 days after the
                    Employee gives the Company written notice of such breach;

              (b)   the Company shall make a general assignment for benefit of
                    creditors; or any proceeding shall be instituted by the
                    Company seeking to adjudicate it as bankrupt or insolvent,
                    or seeking liquidation, winding up, reorganization,
                    arrangement, adjustment, protection, relief, or composition
                    of it or its debts under law relating to bankruptcy,
                    insolvency or reorganization or relief of debtors, or
                    seeking entry of an order for relief or the appointment of a
                    receiver, trustee, or other similar official for it or for
                    any substantial part of its property or the Company shall
                    take any corporate action to authorize any of the actions
                    set forth above in this subsection 5(b);

              (c)   an involuntary petition shall be filed or an action or
                    proceeding otherwise commenced against the Company seeking
                    reorganization, arrangement or readjustment of the Company's
                    debts or for any other relief under the Federal Bankruptcy
                    Code, as amended, or under any other bankruptcy or
                    insolvency act or law, state or federal, now or hereafter
                    existing and remain undismissed or unstayed for a period of
                    30 days; or

              (d)   a receiver, assignee, liquidator, trustee or similar officer
                    for the Company or for all or any part of its property shall
                    be appointed involuntarily.

              (e)   a Change in Control as defined in Section 14.

6.     SEVERANCE.

       6.1    If (i) the Company terminates this Agreement without Cause or (ii)
              the Employee terminates this Agreement pursuant to Section 5.1(a),
              then: (1) except in the case of death or disability, the Company
              shall continue to pay Employee his then-current salary for the
              remaining period of the applicable Term; (2) all stock options
              granted pursuant to this Agreement that would have vested during
              the Term shall vest immediately prior to such termination; and (3)
              the Company shall continue to provide all benefits subject to
              COBRA at its expense for up to one year.

       6.2    In the event of a consummation of a Change in Control of the
              Company, and if the Employee gives notice of termination within 90
              days after such occurrence, then (i) all stock, stock options,
              stock awards, and similar equity rights granted to the Employee
              shall immediately vest and remain fully exercisable through their
              original term with all rights; and (ii) the Company shall continue
              to pay the Employee his then-current salary for the shorter of (a)
              six months, or (b) the remaining period of the applicable Term.

7.     OTHER BENEFITS.

       In addition to all other benefits contained herein, the Employee shall be
entitled to:

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       (a)    Vacation time of four weeks per year taken in accordance with the
              vacation policy of the Company.

       (b)    After six years of employment, one three-month period of fully
              paid leave of absence in accordance with Company policies in place
              at that time; it being understood that such policies may restrict
              the Employee from taking such leave of absence until a time that
              is acceptable to the Company and may include other such
              limitations.

       (c)    Group health, disability and life insurance.

       (d)    The Company shall provide the Employee with an automobile
              allowance of $750 per month and standard tax preparation and
              planning services.

8.     CONFIDENTIALITY.

       8.1    The Employee acknowledges that, during the course of performing
              his services hereunder, the Company shall be disclosing
              information to the Employee related to the Company's Field of
              Interest, Inventions, projects and business plans, as well as
              other information (collectively, "Confidential Information"). The
              Employee acknowledges that the Company's business is extremely
              competitive, dependent in part upon the maintenance of secrecy,
              and that any disclosure of the Confidential Information would
              result in serious harm to the Company.

       8.2    The Employee agrees that the Confidential Information only shall
              be used by the Employee in connection with his activities
              hereunder as an employee of the Company, and shall not be used in
              any way that is detrimental to the Company.

       8.3    The Employee agrees not to disclose, directly or indirectly, the
              Confidential Information to any third person or entity, other than
              representatives or agents of the Company. The Employee shall treat
              all such information as confidential and proprietary property of
              the Company.

       8.4    The term "Confidential Information" does not include information
              that (a) is or becomes generally available to the public other
              than by disclosure in violation of this Agreement, (b) was within
              the Employee's possession prior to being furnished to such
              Employee, (c) becomes available to the Employee on a
              nonconfidential basis or (d) was independently developed by the
              Employee without reference to the information provided by the
              Company.

       8.5    The Employee may disclose any Confidential Information that is
              required to be disclosed by law, government regulation or court
              order. If disclosure is required, the Employee shall give the
              Company advance notice so that the Company may seek a protective
              order or take other action reasonable in light of the
              circumstances.

       8.6    Upon termination of this Agreement, the Employee shall promptly
              return to the Company all materials containing Confidential
              Information, as well as data, records, reports and other property,
              furnished by the Company to the Employee or produced by the
              Employee in connection with services rendered hereunder.
              Notwithstanding such return or any of the provisions of this
              Agreement, the Employee shall continue to be bound by the terms of
              the confidentiality provisions contained in this Section 8 for a
              period of three years after the termination of this Agreement.

       8.7    In connection with his employment by the Company, the Employee
              hereby acknowledges that he may enter into more than one agreement
              with regard to (a) the confidentiality of certain books, records,
              documents and business, (b) rights to certain inventions,
              proprietary

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              information, and writings, (c) publication of certain materials,
              and (d) other related matters (the "Confidential Matters") of the
              Company (the "Confidentiality Agreements"). In order to clarify
              any potential conflicts between certain respective provisions of
              such Confidentiality Agreements, the Employee and the Company
              hereby agree that, as among such Confidentiality Agreements, the
              provision (or part thereof) in any such Confidentiality Agreement
              which affords the greatest protection to the Company with respect
              to the Confidential Matters shall control.

9.     INVENTIONS DISCOVERED BY THE EMPLOYEE WHILE PERFORMING SERVICES
       HEREUNDER.

       During the Term, the Employee shall promptly disclose to the Company any
       invention, improvement, discovery, process, formula, or method or other
       intellectual property, whether or not patentable, whether or not
       copyrightable (collectively, "Inventions") made, conceived or first
       reduced to practice by the Employee, either alone or jointly with others,
       while performing service hereunder. The Employee hereby assigns to the
       Company all of his right, title and interest in and to any such
       Inventions. During and after the Term, the Employee shall execute any
       documents necessary to perfect the assignment of such Inventions to the
       Company and to enable the Company to apply for, obtain, and enforce
       patents and copyrights in any and all countries on such Inventions. The
       Employee hereby irrevocably designates the Chief Patent Counsel to the
       Company as his agent and attorney-in-fact to execute and file any such
       document and to do all lawful acts necessary to apply for and obtain
       patents and copyrights and to enforce the Company's rights under this
       paragraph. This Section 9 shall survive the termination of this
       Agreement.

10.    NON-COMPETITION AND NON-SOLICITATION.

       During the Term and for a period of one year following the date of
       termination or nonrenewal for any reason (other than termination pursuant
       to Section 5.1(a): (a) the Employee shall not in the United States or in
       any country in which the Company shall then be doing business, directly
       or indirectly, enter the employ of, or render any services to, any
       person, firm or corporation engaged in any business competitive with the
       business of the Company or of any of its subsidiaries or affiliates of
       which the Employee may become an employee or officer during the Term; he
       shall not engage in such business on his own account; and he shall not
       become interested in any such business, directly or indirectly, as an
       individual, partner, shareholder, director, officer, principal, agent,
       employee, trustee, consultant, or any other relationship or capacity;
       provided, however, that nothing contained in this Section 10 shall be
       deemed to prohibit the Employee from acquiring, solely as an investment,
       shares of capital stock of any public corporation; (b) neither the
       Employee nor any Affiliate of the Employee shall solicit or utilize, or
       assist any person in any way to solicit or utilize, the services,
       directly or indirectly, of any of the Company's directors, consultants,
       members of the Board of Scientific and Medical Advisors, officers or
       employees (collectively, "Associates of the Company"). This
       nonsolicitation and nonutilization provision shall not apply to
       Associates of the Company who have previously terminated their
       relationship with the Company.

       10.1   If the Employee commits a breach, or threatens to commit a breach,
              of any of the provisions of this Section 10, the Company shall
              have the following rights and remedies:

              10.1.1  The right and remedy to have the provisions of this
                      Agreement specifically enforced by any court having equity
                      jurisdiction, it being acknowledged and agreed that any
                      such breach or threatened breach shall cause irreparable
                      injury to the Company and that money damages shall not
                      provide an adequate remedy to the Company; and

              10.1.2  The right and remedy to require the Employee to account
                      for and pay over to the Company all compensation, profits,
                      monies, accruals, increments or other benefits
                      (collectively "Benefits") derived or received by the
                      Employee as the result of any

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                      transactions constituting a breach of any of the
                      provisions of the preceding paragraph, and the Employee
                      hereby agrees to account for and pay over such Benefits
                      to the Company. Each of the rights and remedies enumerated
                      above shall be independent of the other, and shall be
                      severally enforceable, and all of such rights and remedies
                      shall be in addition to, and not in lieu of, any other
                      rights and remedies available to the Company under law or
                      in equity.

       10.2   If any of the covenants contained in Section 8, 9 or 10, or any
              part thereof, is hereafter construed to be invalid or
              unenforceable, the same shall not affect the remainder of the
              covenant or covenants, which shall be given full effect without
              regard to the invalid portions.

       10.3   If any of the covenants contained in Section 8, 9 or 10, or any
              part thereof, is held to be unenforceable because of the duration
              of such provision or the area covered thereby, the parties agree
              that the court making such determination shall have the power to
              reduce the duration and/or area of such provision and, in its
              reduced form, such provision shall then be enforceable.

       10.4   The parties hereto intend to and hereby confer jurisdiction to
              enforce the covenants contained in Sections 8, 9 and 10 upon the
              courts of any state within the geographical scope of such
              covenants. In the event that the courts of any one or more of such
              states shall hold any such covenant wholly unenforceable by reason
              of the breadth of such scope or otherwise, it is the intention of
              the parties hereto that such determination not bar or in any way
              affect the Company's right to the relief provided above in the
              courts of any other states within the geographical scope of such
              covenants, as to breaches of such covenants in such other
              respective jurisdictions, the above covenants as they relate to
              each state being, for this purpose, severable into diverse and
              independent covenants.

11.    INDEMNIFICATION.

       The Company shall indemnify the Employee, to the maximum extent permitted
       by applicable law, against all costs, charges and expenses incurred or
       sustained by him in connection with any action, suit or proceeding to
       which he may be made a party by reason of his being an officer, director
       or employee of the Company or of any subsidiary or affiliate of the
       Company. The Company shall provide, subject to its availability upon
       reasonable terms (which determination shall be made by the Board) at its
       expense, directors and officers insurance for the Employee in reasonable
       amounts. Determination with respect to (a) the availability of insurance
       upon reasonable terms and (b) the amount of such insurance coverage shall
       be made by the Board in its sole discretion.

12.    NOTICES.

       All notices, requests, consents and other communications required or
       permitted to be given hereunder shall be in writing and shall be deemed
       to have been duly given if sent by prepaid telegram (confirmed delivery
       by the telegram service), private overnight mail service (delivery
       confirmed by such service), registered or certified mail (return receipt
       requested), or delivered personally, as follows (or to such other address
       as either party shall designate by notice in writing to the other in
       accordance herewith):

If to the Company:

ARIAD Pharmaceuticals, Inc.
26 Landsdowne Street
Cambridge, Massachusetts 02139
Attention: Chief Executive Officer

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Telephone:        (617) 494-0400
Fax:              (617) 494-1828


If to the Employee:

Mr. Edward M. Fitzgerald
22 Yorkshire Road
Dover, Massachusetts 02030

13.    GENERAL.

       13.1   This Agreement shall be governed by and construed and enforced in
              accordance with the laws of the Commonwealth of Massachusetts
              applicable to agreements made and to be performed entirely in
              Massachusetts.

       13.2   The Section headings contained herein are for reference purposes
              only and shall not in any way affect the meaning or interpretation
              of this Agreement.

       13.3   This Agreement sets forth the entire agreement and understanding
              of the parties relating to the subject matter hereof, and
              supersedes all prior agreements, arrangements and understandings,
              written or oral, relating to the subject matter hereof. No
              representation, promise or inducement has been made by either
              party that is not embodied in this Agreement, and neither party
              shall be bound by or liable for any alleged representation,
              promise or inducement not so set forth.

       13.4   This Agreement and the Employee's rights and obligations hereunder
              may not be assigned by the Employee or the Company; provided,
              however, the Company may assign this Agreement to an Affiliate or
              a successor-in interest.

       13.5   This Agreement may be amended, modified, superseded, canceled,
              renewed or extended, and the terms or covenants hereof may be
              waived, only by a written instrument executed by the parties
              hereto, or in the case of a waiver, by the party waiving
              compliance. The failure of a party at any time or times to require
              performance of any provision hereof shall in no manner affect the
              right at a later time to enforce the same. No waiver by a party of
              the breach of any term or covenant contained in this Agreement,
              whether by conduct or otherwise, in any one or more instances,
              shall be deemed to be, or construed as, a further or continuing
              waiver of any such breach, or a waiver of the breach of any other
              term or covenant contained in this Agreement.

14.    DEFINITIONS.  As used herein the following terms have the following
       meaning:

       (a)    "Affiliate" means and includes any corporation or other business
              entity controlling, controlled by or under common control with the
              corporation in question.

       (b)    The "Company's Field of Interest" is the discovery, development
              and commercialization of pharmaceutical products based on (a)
              intervention in signal transduction pathways and (b) gene and cell
              therapy. The Company's Field of Interest may be changed at any
              time at the sole discretion of the Company and upon written notice
              to Employee.

       (c)    "Person" means any natural person, corporation, partnership, firm,
              joint venture, association, joint stock company, trust,
              unincorporated organization, governmental body or other entity.

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       (d)    "Subsidiary" means any corporation or other business entity
              directly or indirectly controlled by the corporation in question.

       (e)    "Change in Control" means the occurrence of any of the following
              events (without the consent of the Employee):

              (i)   Any corporation, person or other entity makes a tender or
                    exchange offer for shares of the Company's Common Stock
                    pursuant to which such corporation, person or other entity
                    acquires more than 50% of the issued and outstanding shares
                    of the Company's Common Stock;

              (ii)  The stockholders of the Company approve a definitive
                    agreement to merge or consolidate the Company with or into
                    another corporation or to sell or otherwise dispose of all
                    or substantially all of the Company's assets; or

              (iii) Any person within the meaning of Section 3 (a) (9) or
                    Section 13 (d) of the Securities Exchange Act of 1934
                    acquires more than 50% of the combined voting power of
                    Company's issued and outstanding voting securities entitled
                    to vote in the election of the Board."


THIS SPACE INTENTIONALLY LEFT BLANK

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IN WITNESS WHEREOF, the parties have executed this

Agreement as of the date first above written.


                                       ARIAD PHARMACEUTICALS, INC.



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




                                       EMPLOYEE



                                       -----------------------------------------
                                       Edward M. Fitzgerald



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