Document:

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                                                                    EXHIBIT 10.5

                               IMMUNEX CORPORATION

                      PROFIT SHARING 401(k) PLAN AND TRUST

               (As Amended and Restated Effective January 1, 2000)

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                                    CONTENTS

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<S>                                                                         <C>
I.   NAME AND EFFECTIVE DATE............................................... I-1
     1.1    Name........................................................... I-1
     1.2    Effective Date................................................. I-1

II.  DEFINITIONS........................................................... II-1
     2.1    Accounts....................................................... II-1
     2.2    Accrued Benefit................................................ II-1
     2.3    Affiliate...................................................... II-1
     2.4    Allocable Income............................................... II-1
     2.5    Beneficiary.................................................... II-1
     2.6    Board.......................................................... II-2
     2.6    Code........................................................... II-2
     2.7    Compensation................................................... II-2
     2.8    Computation Period............................................. II-3
     2.9    Employee....................................................... II-3
     2.10   Employer....................................................... II-4
     2.11   Enrollment Date................................................ II-4
     2.12   ERISA.......................................................... II-4
     2.13   Highly Compensated Employee.................................... II-4
     2.14   Hour of Service................................................ II-5
     2.15   Investment Fund................................................ II-7
     2.16   Investment Manager............................................. II-7
     2.17   Limitation Year................................................ II-7
     2.18   Nonhighly Compensated Employee................................. II-7
     2.19   Normal Retirement Age.......................................... II-8
     2.20   One-Year Break in Service...................................... II-8
     2.21   Participant.................................................... II-8
</TABLE>

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<TABLE>
<S>                                                                        <C>
      2.22  Participant Elected Contribution.............................  II-8
      2.23  Plan or Trust................................................  II-8
      2.24  Plan Administrator or Committee..............................  II-8
      2.25  Plan Year....................................................  II-8
      2.26  Required Beginning Date......................................  II-8
      2.27  Salary Deferral Agreement....................................  II-9
      2.28  Section 402(g) Limit.........................................  II-9
      2.29  Spouse.......................................................  II-9
      2.30  Surviving Spouse.............................................  II-10
      2.31  Trust Fund or Fund...........................................  II-10
      2.32  Trustee......................................................  II-10
      2.33  Trust Fund or Fund...........................................  II-10
      2.34  Valuation Date...............................................  II-10
      2.35  Year of Service..............................................  II-10

III.  ELIGIBLE EMPLOYEES.................................................  III-1
      3.1   Participation................................................  III-1
      3.2   Participation on Reemployment................................  III-1
      3.3   Ineligible Employees.........................................  III-2
      3.4   Inactive Participants........................................  III-2
      3.5   End of Participation.........................................  III-3
      3.6   Qualified Military Service...................................  III-3

IV.   CONTRIBUTIONS......................................................  IV-1
      4.1   Participant Elected Contributions............................  IV-1
      4.2.  Employer Matching Contributions..............................  IV-5
      4.3.  Employer's Profit Sharing Contribution.......................  IV-6
      4.4   Employee Contributions.......................................  IV-6
      4.5   Nondiscrimination Test:  Matching Contributions
            and Employee Contributions...................................  IV-6
      4.6   Rollover Contributions.......................................  IV-8
</TABLE>

Immunex Corporation Profit Sharing 401(k) Plan anf Trust                 Page ii

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<TABLE>
<S>                                                                               <C>
V.     PARTICIPANT ACCOUNTS AND CREDITING OF CONTRIBUTIONS......................  V-1
       5.1  Accounts............................................................  V-1
       5.2  Allocation and Crediting of Contributions...........................  V-1
       5.3  Valuation of Assets.................................................  V-2
       5.4  Adjustment of Participants' Accounts................................  V-2
       5.5  Limitation on Allocations...........................................  V-3
       5.6  Controlled Groups...................................................  V-5
       5.7  Protection of Accrued Benefits......................................  V-5
       5.8  Title to Assets in Trustee..........................................  V-5

VI.    INVESTMENT FUNDS.........................................................  VI-1
       6.1  Separate Funds......................................................  VI-1
       6.2  Participant Direction...............................................  VI-1
       6.3  Investment Results..................................................  VI-1
       6.4  Voting of Stock Held in Investment Funds............................  VI-1
       6.5  Voting of Employer Stock............................................  VI-1
       6.6  Tender of Employer Stock............................................  VI-2

VII.   PARTICIPANT LOANS........................................................  VII-1
       7.1  Loans to Participants...............................................  VII-1
       7.2  Accounting for Loans................................................  VII-4

VIII.  NONFORFEITABLE BENEFITS..................................................  VIII-1
       8.1  Nonforfeitable Interest.............................................  VIII-1
       8.2  Years of Service....................................................  VIII-1
       8.3  No Increase in Pre-break Vesting....................................  VIII-2
       8.4  Forfeitable Interests...............................................  VIII-2
       8.5  Distribution to Separated Participants..............................  VIII-4

IX.    RETIREMENT...............................................................  IX-1
       9.1  Retirement Age and Benefit..........................................  IX-1
</TABLE>

Immunex Corporation Profit Sharing 401(k) Plan anf Trust                Page iii

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<S>                                                                               <C>
X.     DEATH BENEFIT............................................................  X-1
       10.1  Death of Participant...............................................  X-1
       10.2  Payments Upon Failure to Designate Beneficiary.....................  X-1

XI.    DISABILITY BENEFIT.......................................................  XI-1
       11.1  Payment Due........................................................  XI-1
       11.2  "Permanently Disabled".............................................  XI-1

XII.   DISTRIBUTIONS AND WITHDRAWALS............................................  XII-1
       12.1  Distribution of Benefits...........................................  XII-1
       12.2  Required Distributions.............................................  XII-2
       12.3  Distributions to Minors and Incompetents...........................  XII-4
       12.4  Qualified Domestic Relations Orders................................  XII-4
       12.5  Hardship Distributions.............................................  XII-6
       12.6  Direct Rollover Distributions......................................  XII-8
       12.7  Waiver of 30-Day Election Period...................................  XII-9

XIII.  TOP HEAVY PROVISIONS.....................................................  XIII-1
       13.1  Applicability......................................................  XIII-1
       13.2  Definitions........................................................  XIII-1
       13.3  Minimum Contributions..............................................  XIII-4
       13.5  Benefits Under Different Plans.....................................  XIII-5

XIV.   PROVISION AGAINST ANTICIPATION...........................................  XIV-1

XV.    ADMINISTRATIVE COMMITTEE - NAMED FIDUCIARY AND ADMINISTRATOR.............  XV-1
       15.1  Appointment of Committee...........................................  XV-1
       15.2  Committee Action...................................................  XV-1
       15.3  Rights and Duties..................................................  XV-1
       15.4  Investments........................................................  XV-3
       15.5  Information, Reporting and Disclosure..............................  XV-3
       15.6  Independent Qualified Accountant...................................  XV-3
</TABLE>

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<S>                                                                              <C>
         15.7   Standard of Care Imposed Upon the Committee.....................  XV-4
         15.8   Allocation and Delegation of Responsibility.....................  XV-4
         15.9   Bonding.........................................................  XV-5
         15.10  Claims Procedure................................................  XV-5
         15.11  Unclaimed Account Procedures....................................  XV-9
         15.12  Funding Policy..................................................  XV-10
         15.13  Indemnification.................................................  XV-10

XVI.     APPOINTMENT OF INVESTMENT MANAGER......................................  XVI-1
         16.1   Authority for Appointment.......................................  XVI-1
         16.2   Investment Manager Discretion...................................  XVI-1

XVII.    INVESTMENT OF TRUST FUNDS BY TRUSTEE...................................  XVII-1

XVIII.   POWERS AND DUTIES OF TRUSTEE...........................................  XVIII-1
         18.1   Powers of Trustee...............................................  XVIII-1
         18.2   Annual Accounts.................................................  XVIII-3
         18.3   Notices and Directions..........................................  XVIII-3
         18.4   Standard of Care Imposed Upon Trustee...........................  XVIII-4
         18.5   Trustee's Acknowledgment of Responsibility......................  XVIII-5

XIX.     CONSTRUCTION...........................................................  XIX-1

XX.      LIABILITY OF TRUSTEE...................................................  XX-1
         20.1   Actions of Trustee Conclusive...................................  XX-1
         20.2   Distributions by Trustee........................................  XX-1
         20.3   Expenses of Administration......................................  XX-1
         20.4   Indemnity of Trustee............................................  XX-1

XXI.     RESIGNATION OR REMOVAL OF TRUSTEE......................................  XXI-1
         21.1   Resignation.....................................................  XXI-1
         21.2   Removal.........................................................  XXI-1
         21.3   Settlement of Account...........................................  XXI-1
</TABLE>

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<S>                                                                                 <C>
XXII.    SUITS....................................................................  XXII-1

XXIII.   MERGERS AND CONSOLIDATIONS...............................................  XXIII-1

XXIV.    AMENDMENT AND TERMINATION OF PLAN........................................  XXIV-1
         24.1   Right to Amend and Terminate......................................  XXIV-1
         24.2   No Revesting......................................................  XXIV-1
         24.3   Exclusive Benefit of Participants.................................  XXIV-1
         24.4   Termination and Discontinuance of Contributions...................  XXIV-1

XXV.     RIGHT TO DISCHARGE EMPLOYEES.............................................  XXV-1

XXVI.    RETURN OF CONTRIBUTIONS..................................................  XXVI-1
         26.1   Mistake of Fact...................................................  XXVI-1
         26.2   Allowance of Deductibility........................................  XXVI-1

XXVII.   PUERTO RICO..............................................................  XXVII-2
</TABLE>

Immunex Corporation Profit Sharing 401(k) Plan and Trust                 Page vi

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                               IMMUNEX CORPORATION

                      PROFIT SHARING 401(k) PLAN AND TRUST

     THIS DOCUMENT, made and executed by Immunex Corporation, a Washington
corporation, hereinafter referred to as the "Employer":

                                   WITNESSETH

     WHEREAS, the Employer established its profit sharing plan effective as of
January 1, 1987 and to conform the plan to applicable law, the Employer intends
to amend the plan by complete restatement; and

     WHEREAS, the Employer intends that the plan and trust established hereunder
be qualified under Sections 401(a) and 401(k) of the Internal Revenue Code (the
"Code") and be exempt from federal income taxation under Section 501(a) of the
Code; and

     WHEREAS, the form of this plan and trust has been approved by the Employer;

     NOW, THEREFORE, it is agreed:

Immunex Corporation Profit Sharing 401(k) Plan and Trust

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                           I.  NAME AND EFFECTIVE DATE

1.1  Name

     This Plan shall be known as the Immunex Corporation Profit Sharing 401(k)
     Plan and Trust.

1.2  Effective Date

     The original effective date of the Plan was January 1, 1987. Unless
     specifically provided otherwise, the effective date of this Agreement (and
     the amended and restated Plan set forth herein) shall be January 1, 2000.
     The benefit payable to or on behalf of a Participant included under the
     Plan in accordance with the following provisions shall not be affected by
     the terms of any amendment to the Plan adopted after such Participant's
     service with the Employer terminates, unless the amendment expressly
     provides otherwise.

Immunex Corporation Profit Sharing 401(k) Plan and Trust                Page I-1

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                                II.  DEFINITIONS

Whenever used herein, unless the context clearly indicates otherwise, masculine,
feminine, and neuter words may be used interchangeably, singular shall mean the
plural and vice versa, and the following words and phrases shall have the
following meanings:

2.1  Accounts

     "Accounts" means the individual separate Accounts established by the Plan
     Administrator in the name of each Participant in accordance with the Plan.

2.2  Accrued Benefit

     "Accrued Benefit" means the balance of a Participant's Accounts including
     investment experience, as of the most recent Valuation Date, plus
     accumulated contributions since such date and less any distributions since
     such date.

2.3  Affiliate

     "Affiliate" means any member of a controlled group of corporations (within
     the meaning of Code Section 414(b), as modified in accordance with Code
     Section 415(h) for purposes of Sections 5.5 and 5.6), a group of trades or
     businesses under common control (within the meaning of Code Section 414(c),
     as modified in accordance with Code Section 415(h) for purposes of Sections
     5.5 and 5.6) or an affiliated service group (within the meaning of Code
     Section 414(m) or (o)) of which the Employer is a member.

2.4  Allocable Income

     "Allocable Income" means net income or net loss. To calculate Allocable
     Income for the Plan Year, the Plan Administrator will use a uniform
     nondiscriminatory method that reasonably reflects the manner used by the
     Plan to allocate income to the Participant's Accounts. Allocable Income
     will not be determined for the period between the end of the Plan Year and
     the date of distribution.

2.5  Beneficiary

     "Beneficiary" means the person or persons designated as such by a
     Participant in accordance with Article X.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-1

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2.6  Board

     "Board" means the Board of Directors of Immunex Corporation.

2.6  Code

     "Code" means the Internal Revenue Code of 1986, as amended.

2.7  Compensation

     Except as otherwise expressly modified by other provisions of the Plan,
     "Compensation" means an Employee's wages, salary, fees for professional
     services and other amounts received during the Plan Year (without regard to
     whether or not an amount is paid in cash) for personal services actually
     rendered in the course of employment with the Employer to the extent that
     such amounts are includible in gross income, including, but not limited to,
     overtime, bonuses and commissions, but excluding fringe benefits and
     reimbursements or other expense allowances under a nonaccountable plan (as
     defined in Treasury Regulation (S) 1.62-2(c)). Compensation shall not
     include Employer contributions to a plan of deferred compensation to the
     extent that, before the application of the Section 415 limitations to that
     plan, the contributions are not includible in the employee's gross income
     for the taxable year in which contributed; deductible Employer
     contributions to a simplified employee pension plan described in Code
     Section 408(k); distribution from a plan of deferred compensation,
     regardless of whether such amounts are includible in the employee's gross
     income when distributed; amounts realized from the exercise of a
     non-qualified stock option or when restricted stock (or property) held by
     an employee becomes freely transferable or is no longer subject to a
     substantial risk of forfeiture; amounts realized from the sale, exchange or
     other disposition of stock acquired under a qualified stock option; or any
     other amounts which receive special tax benefits. Notwithstanding the
     foregoing, (i) Compensation shall include amounts excludable from the
     Employee's gross income by reason of Code Section 125, 402(e)(3), 402(h) or
     403(b), and (ii) solely for purposes of Sections 2.27, 4.1A, 4.1E, 4.2A and
     5.2A, Compensation shall not include commissions or, effective March 1,
     2002, retention bonuses. Effective on and after January 1, 2001,
     Compensation shall also include amounts excludable from the Employee's
     gross income for qualified taxable fringe benefits pursuant to Code Section
     132(f)(4).

     A Participant's Compensation for any Plan Year shall not exceed the
     Compensation Limit in effect under Code Section 401(a)(17), as adjusted for
     increases in the cost-of-living in accordance with Code

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-2

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     Section 401(a)(17)(B) for such Plan Year. The Compensation Limit in effect
     for any Plan Year is the Compensation Limit in effect at the beginning of
     that Plan Year. For a Plan Year of less than 12 months, the Compensation
     Limit is a prorated dollar amount, determined by multiplying the
     Compensation Limit by a fraction, the numerator of which equals the number
     of months in the short period and the denominator of which equals 12.

2.8  Computation Period

     "Computation Period" shall mean a twelve (12) consecutive month period
     designated for purposes of determining an Employee's Years of Service and
     One-Year Breaks in Service for benefit accrual and vesting as follows:

          Eligibility Computation Period shall mean the twelve (12) consecutive
          month period beginning on the date on which the Employee first
          completes an Hour of Service. The second and subsequent Eligibility
          Computation Periods shall be the Plan Year, beginning with the Plan
          Year that includes the first anniversary of the date on which the
          Employee first completed an Hour of Service. In the case of an
          Employee who incurs a One-Year Break in Service prior to becoming a
          Participant, a new Eligibility Computation Period shall begin on the
          date on which the Employee first completes an Hour of Service
          following such One-Year Break in Service. The second and subsequent
          Eligibility Computation Periods for such Employee shall be the Plan
          Year, beginning with the Plan Year that includes the first anniversary
          of the date on which the Employee first completed an Hour of Service
          following his reemployment.

          Accrual Computation Period shall mean the Plan Year.

          Vesting Computation Period shall mean the Plan Year.

2.9  Employee

     "Employee" means any person, including officers, in the service of the
     Employer. Employee shall not mean an independent contractor. Employee shall
     also mean any leased employee, within the meaning of Code Section 414(n),
     unless such leased employee is covered by a plan maintained by the leasing
     organization that meets the requirements of Code Section 414(n)(5)(B) and
     leased employees do not constitute more than 20 percent of the Employer's
     Nonhighly Compensated Employee work force.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-3

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2.10 Employer

     "Employer" means Immunex Corporation and any Affiliate that, with the
     consent of the Board, elects to adopt the Plan and any organization that
     acquires the Employer's business and adopts the Plan; provided, that for
     purposes of Article XV (Administrative Committee) and Article XXIV
     (Amendment and Termination of Plan), Employer means Immunex Corporation.

2.11 Enrollment Date

     "Enrollment Date" means the first day of any month and shall be the date on
     which the Employee commences participation in the Plan.

2.12 ERISA

     "ERISA" means the Employee Retirement Income Security Act of 1974, as
     amended.

2.13 Highly Compensated Employee

     A.   Effective for Plan Years beginning on and after January 1, 1997,
          "Highly Compensated Employee" means an Employee who:

          1.   Was a more than 5% owner of an Employer (applying the
               constructive ownership rules of Code Section 318) during the Plan
               Year or during the preceding 12-month period; or

          2.   For the preceding Plan Year (i) had Compensation in excess of
               $80,000 (as adjusted by the Commissioner of Internal Revenue for
               the relevant year); and (ii) if the Employer so elects, was in
               the top-paid group of Employees (i.e., the group consisting of
               the top 20% of the Employees when ranked on the basis of
               Compensation paid during such Plan Year).

     B.   A Highly Compensated Employee also includes a former Employee who must
          be treated as a Highly Compensated Employee for the relevant Plan Year
          pursuant to Regulation Section 1.414(q)-1T Q&A-4 and Notice 97-45.

     C.   The Employer and its Affiliates shall be treated as a single Employer
          for purposes of determining the number and identity of Highly
          Compensated Employees.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-4

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2.14 Hour of Service

     "Hour of Service" means the following:

     A.   Each hour for which an Employee is paid, or entitled to payment, for
          the performance of duties for the Employer during the applicable
          Computation Period.

     B.   Each hour for which an Employee is paid, or entitled to payment, by
          the Employer on account of a period of time during which no duties are
          performed (irrespective of whether the employment relationship has
          terminated) due to vacation, holiday, illness, incapacity (including
          disability), layoff, jury duty, military duty or leave of absence.

          Notwithstanding the preceding sentence,

          1.   No more than 501 Hours of Service shall be credited under this
               paragraph to an Employee on account of any single continuous
               period during which the Employee performs no duties (whether or
               not such period occurs in a single Computation Period);

          2.   An hour for which an Employee is directly or indirectly paid, or
               entitled to payment, on account of a period during which no
               duties are performed is not required to be credited to the
               Employee if such payment is made or due under an insured
               disability plan or a plan maintained solely for the purposes of
               complying with applicable worker's compensation, unemployment
               compensation, or disability insurance laws;

          3.   Hours of Service are not required to be credited for a payment
               that solely reimburses an Employee for medically related expenses
               incurred by the Employee; and

          4.   For purposes of this paragraph, a payment shall be deemed to be
               made by or due from the Employer, regardless of whether such
               payment is made by or due from the Employer directly or
               indirectly through a trust fund or insurer to which the Employer
               contributes or pays premiums, and, regardless of whether
               contributions made or due to the trust fund, insurer or other
               entity are for the benefit of particular Employees or are on
               behalf of a group of Employees in the aggregate.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-5

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     C.   Each hour for which back pay, irrespective of mitigation of damages,
          is either awarded or agreed to by the Employer. The same Hours of
          Service shall not be credited both under paragraph A or paragraph B,
          as the case may be, and under this paragraph C.

     D.   Each hour with which an Employee would normally be credited (or eight
          hours per normal working day if the Plan is unable to determine the
          Employee's hours) during the Employee's absence from work if the
          Employee's absence commences in a Plan Year beginning after December
          31, 1984, and the absence is because of the Employee's pregnancy, the
          birth of the Employee's child, or the placement of a child with the
          Employee in connection with the Employee's adoption of the child, or
          for the purpose of caring for such child for a period beginning
          immediately after the child's birth or placement. An Employee shall be
          credited with the Employee's Hours of Service determined under this
          paragraph D only for the purpose of determining whether the Employee
          has incurred a One-Year Break in Service and the number of Hours of
          Service credited to an Employee in connection with such pregnancy or
          placement shall not exceed 501. Hours of Service credited under this
          paragraph D shall be credited in the Computation Period in which the
          Employee's absence begins or in the next following Computation Period
          if the Hours of Service credited under this paragraph are not needed
          to prevent the Employee from incurring a One-Year Break in Service in
          the earlier Computation Period. The Plan Administrator may establish
          reasonable requirements for information to be furnished by the
          Employee to show that the Employee's absence is for a reason referred
          to under this paragraph and the number of days of such absence. The
          Employee shall be credited with the Employee's Hours of Service under
          this paragraph only if the Employee provides the required information
          on a timely basis.

     E.   Other than as specifically required under this Section, the
          determination of Hours of Service for reasons other than the
          performance of duties and the crediting of Hours of Service to
          Computation Periods shall be in accordance with Department of Labor
          Regulations (S) 2530.200b-2(b) and (c), and such rules are hereby
          incorporated by reference.

     F.   For purposes of eligibility and vesting, service with an Affiliate
          (while it is an Affiliate) shall be considered service with the
          Employer and Hours of Service shall be credited, in accordance with
          this Section, for such service. In addition, effective January 1,
          2002, for purposes of

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-6

<PAGE>

          eligibility and vesting, individuals who are Employees of Greenwich
          Holdings Inc. on January 1, 2002 (or who transfer from service covered
          by the American Home Products Corporation Savings Plan to an Employer
          as a result of, and by the first September 30 following, Immunex
          Corporation's acquisition of Greenwich Holdings Inc.) will be credited
          with the service they had accrued as of December 31, 2001 (or, if
          later, as of the date they transfer to an Employer) under the American
          Home Products Corporation Savings Plan.

     G.   Hours of Service shall also be credited for all purposes under the
          Plan to a leased employee, as defined in Code Section 414(n), for such
          employee's service to the Employer as a leased employee.

2.15 Investment Fund

     "Investment Fund" means a separate portion of the Trust Fund established at
     the direction of the Plan Administrator to provide investment options for
     Participants.

2.16 Investment Manager

     "Investment Manager" means a person, insurance company, corporation,
     partnership or association which is appointed by the Plan Administrator to
     direct the investment and reinvestment of all or any portion of the Trust
     Fund and which qualifies as an "investment manager" under the provisions of
     Section 3(38) of ERISA.

2.17 Limitation Year

     "Limitation Year" shall mean the 12 consecutive month period corresponding
     to the Plan Year and shall be the 12 month period under which the limits of
     Code Section 415 are applied.

2.18 Nonhighly Compensated Employee

     "Nonhighly Compensated Employee" shall mean an Employee who is not a Highly
     Compensated Employee.

2.19 Normal Retirement Age

     "Normal Retirement Age" means age 65.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-7

<PAGE>

2.20 One-Year Break in Service

     "One-Year Break in Service" means a Vesting Computation Period during which
     an Employee fails to complete more than 500 Hours of Service.

2.21 Participant

     "Participant" means an Employee who satisfies the eligibility requirements
     of Article III and who commences participation in the Plan.

2.22 Participant Elected Contribution

     "Participant Elected Contribution" means the amounts designated by a
     Participant pursuant to Section 4.1 and contributed to the Plan by the
     Employer in lieu of payment of an equal amount directly to the Participant
     as compensation.

2.23 Plan or Trust

     "Plan" or "Trust" means this Profit Sharing 401(k) Plan and Trust Agreement
     and all subsequent amendments thereto.

2.24 Plan Administrator or Committee

     "Plan Administrator" or "Committee" means the Administrative Committee as
     appointed by Employer pursuant to Section 15.1.

2.25 Plan Year

     "Plan Year" means the twelve (12) consecutive month period ending on the
     last day of December. The Plan Year shall be the year on which the records
     of the Plan are kept.

2.26 Required Beginning Date

     Effective for Plan Years beginning on and after January 1, 1997, "Required
     Beginning Date" means April 1 of the calendar year following the later of
     the calendar year in which the Participant's Service terminates or the
     calendar year in which the Participant attains age 70 1/2; provided,
     however, that if a Participant is a 5% owner (as defined in Code Section
     416) with respect to the calendar year in which such Participant attains
     age 70 1/2, the Participant's Required Beginning Date is April 1 of the
     calendar year following such calendar year.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page II-8

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     (a)  Any Participant (other than a 5% owner) who attained age 70 1/2 in
          years after 1995 and before January 1, 2002 may elect by April 1 of
          the calendar year following the year in which the Participant attained
          age 70 1/2 (or by December 31, 1997, in the case of a Participant
          attaining age 70 1/2 in 1996) to defer distributions until April 1 of
          the calendar year following the calendar year in which the Participant
          retires. If no such election is made, the Participant will begin
          receiving distributions by the April 1 of the calendar year following
          the calendar year in which the Participant attained age 70 1/2 (or by
          December 31, 1997, in the case of a Participant attaining age 70 1/2
          in 1996.)

     (b)  Any Participant (other than a 5% owner) who attained age 70 1/2 in a
          year prior to 1997 may elect to stop distributions and recommence
          benefit payments by April 1 of the calendar year following the
          calendar year in which the Participant retires.

     A Participant shall be considered a 5% owner for the purpose of this
     Section 2.26 if such Participant is a 5% owner as defined in Code Section
     416(i) at any time during the Plan Year ending with or within the calendar
     year in which such owner attains age 70 1/2. Once minimum required
     distributions begin to a 5% owner, they must continue to be distributed
     even if the Participant ceased to be a 5% owner in a subsequent year.

2.27 Salary Deferral Agreement

     "Salary Deferral Agreement" means the written authorization of a
     Participant to the Employer to deduct from the Participant's Compensation
     an amount or percentage to be deferred as a Participant Elected
     Contribution in accordance with this Plan.

2.28 Section 402(g) Limit

     "Section 402(g) Limit" means the limitation in effect under Code Section
     402(g) for such calendar year.

2.29 Spouse

     "Spouse" means the lawful husband or wife of the Participant.

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2.30 Surviving Spouse

     "Surviving Spouse" means the Participant's Spouse surviving at the date of
     the Participant's death.

2.31 Trust Fund or Fund

     "Trust Fund" or "Fund" means all contributions received by the Trustee for
     purposes of the Plan, the investment thereof, and the earnings and
     appreciation thereon, less payments made to carry out the Plan.

2.32 Trustee

     "Trustee" means Security Trust Company or such other person(s) or
     entity(ies) designated by the Board to serve as trustee of the Trust Fund.

2.33 Trust Fund or Fund

     "Trust Fund" or "Fund" means all property held in the Trust.

2.34 Valuation Date

     "Valuation Date" means the last day of each Plan Year and such other date
     or dates as may be designated by the Plan Administrator.

2.35 Year of Service

     "Year of Service" means:

     A.   Eligibility Service

          For purposes of determining an Employee's eligibility to participate
          in the Plan, Year of Service shall mean the completion of 1,000 or
          more Hours of Service during an Eligibility Computation Period.

     B.   Benefit Accrual Service

          For purposes of determining an Employee's benefit accrual, Year of
          Service shall mean the completion of 1,000 or more Hours of Service
          during an Accrual Computation Period while a Participant.

     C.   Vesting Service

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          For purposes of determining an Employee's nonforfeitable interest in
          the Employee's Accrued Benefit, Year of Service shall mean the
          completion of 1,000 or more Hours of Service during a Vesting
          Computation Period.

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<PAGE>

                            III.  ELIGIBLE EMPLOYEES

3.1  Participation

     A.   Subject to the provisions of Sections 3.1B, 3.1C and 3.3, an Employee
          shall participate in this Plan on the Enrollment Date that coincides
          with or immediately follows the date on which the Employee first
          performs one Hour of Service with the Employer.

     B.   An Employee who is regularly scheduled to work less than twenty (20)
          hours per week shall participate in this Plan on the Enrollment Date
          that coincides with or immediately follows the date on which such
          Employee completes one Year of Eligibility Service or attains age
          twenty-one (21), whichever occurs later.

     C.   An Employee who is classified by the Employer as a temporary employee
          shall participate in this Plan on the Enrollment Date that coincides
          with or immediately follows the date on which such Employee completes
          one Year of Eligibility Service or attains age twenty-one (21),
          whichever occurs later.

     D.   An Employee who is participating in the Plan immediately prior to the
          effective date of this Agreement shall continue to participate in the
          Plan subject to the provisions hereunder.

3.2  Participation on Reemployment

     A.   Subject to the provisions of Section 3.3, a former Participant shall
          resume participation in the Plan upon the date of the Participant's
          reemployment by the Employer if the Participant had a nonforfeitable
          interest under the Plan to any Accrued Benefit derived from Employer
          contributions at the time of the Participant's earlier separation from
          service or the number of the Employee's consecutive One-Year Breaks in
          Service is fewer than the greater of five (5) or the aggregate number
          of the Employee's Years of Service prior to such Break.

     B.   A former Participant who does not resume participation under paragraph
          A of this Section shall be required to again complete the eligibility
          requirement of Section 3.1 before participating in the Plan.

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3.3  Ineligible Employees

     Notwithstanding the provisions of Section 3.1 and Section 3.2, the
     following classes of Employees shall not participate in the Plan:

     A.   An Employee who is covered by a collective bargaining agreement
          between employee representatives and the Employer, unless the
          collective bargaining agreement specifically requires participation in
          this Plan. In applying the preceding sentence, the term "employee
          representatives" shall not include an organization of which more than
          one-half of the members are owners, officers, or executives of the
          Employer.

     B.   A leased employee, within the meaning of Code Section 414(n).

     C.   A non-resident alien with no U.S.-source income (within the meaning of
          Code Section 911(d)(2)) from the Employer.

     D.   A summer intern.

     E.   An individual who is not treated by the Employer as an employee for
          payroll tax purposes, but who is subsequently determined by a
          government agency, by the conclusion or settlement of threatened or
          pending litigation, or otherwise to be (or to have been) an Employee,
          unless and until the Plan Administrator provides that such individual
          is eligible to participate in the Plan (which eligibility shall be on
          a prospective basis only).

3.4  Inactive Participants

     In the event a Participant transfers to an ineligible class of employees,
     such Employee's participation in the Plan for purposes of benefit accrual
     shall cease as of the date of such transfer.

     In the event an ineligible Employee transfers to the eligible class, such
     Employee shall participate in the Plan immediately if the Employee is a
     former Participant or the Employee has previously satisfied the
     requirements of Section 3.1 and would have previously been admitted to
     participation if the Employee had been in the eligible class.

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3.5  End of Participation

     Active participation ends upon suspension of contributions or termination
     of employment. Participation ends when the individual has no further
     account balances under the Plan.

3.6  Qualified Military Service

     Effective December 12, 1994, notwithstanding anything herein to the
     contrary, contributions, benefits and service credit with respect to
     qualified military service will be provided in accordance with Code Section
     414(u).

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<PAGE>

                                IV.  CONTRIBUTIONS

4.1  Participant Elected Contributions

     A.   Election to Defer Compensation

          Each Participant may elect, effective as of the first day of any month
          coincident with or following the Participant's Enrollment Date, by
          filing a Salary Deferral Agreement with the Plan Administrator within
          such time as the Plan Administrator may determine, to defer any whole
          percentage of the Participant's Compensation not to exceed 15% (20%
          for Plan Years beginning on or after January 1, 2002), but in any
          event, the amount of deferral shall not exceed the Section 402(g)
          Limit. Such deferred amounts shall be contributed to the Plan by the
          Employer and designated for such Participant's Deferral Account.
          Contributions shall be made by payroll deduction as authorized by the
          Participant on the Participant's Salary Deferral Agreement. The
          Participant may, in accordance with rules established by the Plan
          Administrator, increase or decrease his elective deferrals effective
          as of the first day of any month; provided, however, a Participant
          shall only be entitled to defer those amounts of Compensation that are
          not currently available to the Participant.

     B.   Payment to Trustee

          The Employer shall transmit the Participant Elected Contributions to
          the Trustee as soon as such Participant Elected Contributions can
          reasonably be segregated from the Employers' general assets, but in
          any event not later than the 15th business day of the month following
          the month in which such amounts would otherwise have been payable to
          the Participant in cash.

     C.   Limitation on Deferral of Compensation

          Effective for Plan Years beginning on and after January 1, 1997, the
          Participant Elected Contributions (together with any qualified
          nonelective contributions that the Plan Administrator may, under
          applicable Treasury Regulations, elect (and does elect) to include in
          the calculation) for a Plan Year shall satisfy one of the following
          tests:

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<PAGE>

          1.   The Average Actual Deferral Percentage of the eligible Highly
               Compensated Employees for the current Plan Year may not be
               greater than the Average Actual Deferral Percentage of the
               eligible Nonhighly Compensated Employees for the prior Plan Year
               multiplied by 1.25; or

          2.   The Average Actual Deferral Percentage of the eligible Highly
               Compensated Employees for the current Plan Year may not be
               greater than the Average Actual Deferral Percentage of the
               eligible Nonhighly Compensated Employees for the prior Plan Year
               multiplied by 2. However, the excess of the Average Actual
               Deferral Percentage of the eligible Highly Compensated Employees
               for the current Plan Year over that of the eligible Nonhighly
               Compensated Employees for the prior Plan Year may not be greater
               than two (2.0) percentage points.

          The "Average Actual Deferral Percentage" for a specified group of
          Employees for a Plan Year shall be the average of the ratios
          (calculated separately for each Employee in such group) of the sum of
          the Participant Elected Contributions (and qualified nonelective
          contributions, if applicable) to the Employee's compensation, as
          defined under Code Section 414(s), for the entire Plan Year or
          compensation while the Participant was eligible to participate. The
          Plan Administrator shall select the Code Section 414(s) definition of
          compensation and the method to be used for the Plan Year and the same
          definition of compensation and method shall be applied to each
          Participant for that year.

          The Plan is subject to Code Section 401(k) and the regulations
          thereunder, which are hereby incorporated in this Document by
          reference. The above tests (and any necessary correction pursuant to
          Section 4.1D) shall be performed in accordance with such Code Section
          and regulations. In order to satisfy the above requirements, the Plan
          Administrator may, in its sole discretion, require the Employer to
          reduce future deferrals elected by the Highly Compensated Employees
          and/or return a portion of the amounts deferred by the Highly
          Compensated Employees in accordance with Section 4.1D.

          A Participant's Participant Elected Contribution shall be taken into
          account for a Plan Year for purposes of the foregoing tests only if it
          is considered allocated as of a date within that Plan Year. A
          Participant's

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<PAGE>

          Participant Elected Contribution is considered allocated as of a date
          within the Plan Year only if:

          1.   The allocation is not contingent upon the Participant's
               participation in the Plan or performance of services on any date
               subsequent to that date; and

          2.   The elective contribution is actually paid to the Trust no later
               than the end of the twelve-month period immediately following the
               Plan Year to which the contribution relates.

          Likewise, a Participant's Participant Elected Contribution shall be
          taken into account for a Plan Year for purposes of the foregoing tests
          only if it relates to compensation that either:

          1.   Would have been received by the Participant in the Plan Year but
               for the Participant's election to defer; or

          2.   Is attributable to services performed by the Participant in the
               Plan Year and, but for the Participant's election to defer, would
               have been received by the Participant within two and one-half
               months after the close of the Plan Year.

          If an amount is returned to an Employee because the Employee's
          elective deferrals for the calendar year exceed the Section 402(g)
          Limit (other than excess elective deferrals of Nonhighly Compensated
          Employees that arise solely from elective deferrals made under the
          Plan or plans of the Employers), such excess deferrals shall
          nevertheless be counted in determining the Employee's actual deferral
          percentage for the Plan Year in which such excess deferrals were made.

          If two or more cash or deferred arrangements (as determined under Code
          Section 401(k)) are treated as a single plan for purposes of Code
          Sections 401(a)(4) or 410(b), such arrangements shall be treated as a
          single plan for purposes of the limitations of this Section.

     D.   Return of Excess Deferrals

          1.   Nondiscrimination Test

               If amounts contributed by the Employer for the Highly Compensated
               Employees cause the Plan to fail to meet the

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<PAGE>

               requirements of Section 4.1C and Code Section 401(k) for a Plan
               Year, then, to the extent that such amounts are in excess of such
               limitations, the excess amounts (called excess contributions)
               shall be returned to the Highly Compensated Employees, together
               with Allocable Income, no later than the close of the following
               Plan Year. Excess contributions shall mean, with respect to any
               Plan Year, the excess of (a) the aggregate amount of Participant
               Elected Contributions (and qualified nonelective contributions,
               if applicable) actually taken into account in computing the
               Average Actual Deferral Percentage of the Highly Compensated
               Employees for such Plan Year, over (b) the maximum amount of such
               contributions permitted by the Average Actual Deferral Percentage
               test (determined by hypothetically reducing contributions made on
               behalf of Highly Compensated Employees in order of the actual
               deferral percentages, beginning with the highest of such
               percentages).

               The excess contributions are then allocated to the Highly
               Compensated Employees with the largest amounts of Participant
               Elected Contributions (and qualified nonelective contributions,
               if applicable) taken into account in calculating the Average
               Actual Deferral Percentage test for the Plan Year in which the
               excess arose, beginning with the Highly Compensated Employee with
               the largest amount of such contributions and continuing in
               descending order until all the excess contributions have been
               allocated. For purposes of the preceding sentence, the "largest
               amount" is determined after distribution of any excess
               contributions. The amount of excess contributions to be returned
               with respect to any Participant for a Plan Year shall be reduced
               by any excess deferrals previously distributed to such
               Participant for the Participant's taxable year ending with or
               within such Plan Year. The amount of excess deferrals that must
               be returned to a Participant for a taxable year shall be reduced
               by any excess contributions previously distributed with respect
               to such Participant for the Plan Year beginning with or within
               such taxable year of the Employer.

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<PAGE>

          2.   Section 402(g) Limit

               If a Participant's elective deferrals (e.g., Participant Elected
               Contributions) under Code Section 401(k) exceed the Section
               402(g) Limit for a calendar year (such excess being called excess
               deferrals), the Plan Administrator shall distribute such excess
               deferrals, together with Allocable Income for the calendar year
               in which the excess deferrals were made, no later than April 15
               of the following calendar year. If a Participant makes elective
               deferrals under the Plan and under any other plan or arrangement
               described in Code Section 402(g)(3) for a Plan Year, and the
               total of such elective deferrals exceeds the Section 402(g)
               Limit, such Participant shall notify the Plan Administrator in
               writing on the prescribed form by March 1 of the succeeding Plan
               Year of the portion of the excess deferrals that he has allocated
               to the Plan and the Plan Administrator shall distribute the
               amount of excess deferrals allocated to this Plan, together with
               Allocable Income, to the Participant no later than April 15 of
               the calendar year following calendar year for which the excess
               deferrals were made.

     E.   Suspension of Deferrals

          A Participant may, upon thirty (30) days' prior written notice filed
          with the Plan Administrator, suspend the Participant's election under
          Section 4.1A to have a portion of the Participant's Compensation
          deferred. In the event of such a suspension, a Participant shall not
          be entitled to again elect to have Participant Elected Contributions
          made hereunder until the first day of the next month. The Participant
          shall, nevertheless, be considered a Participant hereunder for all
          other purposes during such period of time if the Participant's service
          with the Employer continues during that time.

4.2. Employer Matching Contributions

     A.   Basic Matching Contribution

          As soon as practicable following each pay period, the Employer shall
          make a contribution for each Participant who has Compensation deferred
          during that period and who is otherwise eligible, as provided in the
          following sentence, for such contributions. A Participant shall become
          eligible for contributions under this Section 4.2A as of the

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<PAGE>

          January 1 or July 1 coincident with or next following the
          Participant's Enrollment Date. The contribution shall be equal to 100%
          of the first 2% of Compensation deferred by the Participant, plus, for
          Employees with less than five Years of Service, 50% of the amount
          deferred by the Participant that is between 2% and 6% of Compensation,
          and for Employees with five or more Years of Service, 75% of the
          amount deferred by the Participant that is between 2% and 6% of
          Compensation.

     B.   Forfeitures

          Forfeited amounts derived from the Employer Matching Account of a
          Participant who separates from the Employer's service shall be used to
          reduce the Employer's matching contribution for the Plan Year in which
          the forfeited amount becomes available and in subsequent years, if
          necessary.

4.3. Employer's Profit Sharing Contribution

     A.   Discretionary Contribution

          For any Plan Year, the Employer shall have the right to contribute an
          amount that the Employer, in its sole discretion, shall determine. The
          Employer's determination of its discretionary contribution shall be
          binding on all Participants, the Plan Administrator and the Employer.
          In making a discretionary contribution, the Employer shall have the
          discretionary authority to declare that a portion or all of the
          contribution for the Plan Year shall be a qualified nonelective
          contribution as defined in Code Section 401(m)(4)(C), which will be
          allocated as provided in Section 5.2C.

     B.   Date of Payment

          The Employer shall pay its discretionary contribution to the Trustee
          no later than the due date (including extensions thereof) for the
          filing of its federal income tax return for the fiscal year for which
          such contribution is made.

4.4  Employee Contributions

     Other than wage or salary deferrals allowed under Section 4.1A,
     contributions by an Employee under the Plan are not permitted.

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<PAGE>

4.5  Nondiscrimination Test: Matching Contributions and Employee Contributions

     Effective for Plan Years beginning on and after January 1, 1997, in the
     case of Employer Matching Contributions and any other contributions that
     the Employer may elect to include as permitted under Treasury Regulations,
     such contributions shall satisfy one of the following tests:

     A.   The Average Contribution Percentage of the eligible Highly Compensated
          Employees for the current Plan Year shall be not greater than the
          Average Contribution Percentage of the eligible Nonhighly Compensated
          Employees for the prior Plan Year multiplied by 1.25; or

     B.   The Average Contribution Percentage of the eligible Highly Compensated
          Employees for the current Plan Year shall be not greater than the
          Average Contribution Percentage of the eligible Nonhighly Compensated
          Employees for the prior Plan Year multiplied by 2. However, the excess
          of the Contribution Percentage of the eligible Highly Compensated
          Employees for the current Plan Year over that of the eligible
          Nonhighly Compensated Employees for the prior Plan Year shall be not
          greater than two (2.0) percentage points.

     If a Highly Compensated Employee participates in a plan or plans maintained
     by the Employer or an Affiliate under which the Highly Compensated Employee
     is eligible to make elective contributions subject to the requirements of
     Code Section 401(k) and one or more of such plans is also subject to Code
     Section 401(m), the tests applied to the contributions for the Highly
     Compensated Employee shall be performed in accordance with Code Section
     401(m) and the regulations thereunder to prevent the multiple use of the
     alternative limitation as provided in Code Section 401(m).

     If two or more plans are aggregated for purposes of Code Section 410(b) or
     a Highly Compensated Employee participates in two or more plans of the
     Employer and its Affiliates to which matching contributions or employee
     after-tax contributions are made, all such contributions shall be
     aggregated to the extent required under Treasury Regulation (S)
     1.401(m)-1(f)(1)(ii)(B) to apply the requirements of this Section.

     The "Average Contribution Percentage" for a specified group of Employees
     for a Plan Year shall be the average of the ratios (calculated separately
     for each Employee in such group) of the sum of the Employer Matching
     Contributions (and such other contributions as permitted (or required) to
     be included in the

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<PAGE>

     calculation under Treasury Regulations) to the Employee's compensation, as
     defined under Code Section 414(s), for the entire Plan Year or compensation
     while the Participant was eligible to participate. The Plan Administrator
     shall select the Code Section 414(s) definition of compensation and the
     method to be used for the Plan Year and the same definition of compensation
     and method shall be applied to each Participant for that year.

     Contributions that cause the Average Contribution Percentage of the
     eligible Highly Compensated Employees to exceed the limits of this Section
     4.5 shall be distributed to the applicable Participant if vested, or
     forfeited if forfeitable, together with Allocable Income, before the close
     of the following Plan Year. Such excess contributions shall be called
     excess aggregate contributions. (The Employer will incur an excise tax
     equal to 10 percent of the amount of the excess aggregate contributions for
     a Plan Year that are not returned to the appropriate Highly Compensated
     Employees during the first 2-1/2 months of the following Plan Year.) Excess
     aggregate contributions shall mean, with respect to any Plan Year, the
     excess of (i) the aggregate amount of Employer Matching Contributions (and
     such other contributions as permitted (or required) to be included in the
     calculation under Treasury Regulations) actually taken into account in
     computing the Average Contribution Percentage of the Highly Compensated
     Employees for such Plan Year, over (ii) the maximum amount of such
     contributions permitted by the Average Contribution Percentage test
     (determined by hypothetically reducing contributions made on behalf of
     Highly Compensated Employees in order of the contribution percentages,
     beginning with the highest of such percentages). The excess aggregate
     contributions are then allocated to the Highly Compensated Employees with
     the largest amounts of Employer Matching Contributions (and such other
     contributions as permitted (or required) to be included in the calculation
     under Treasury Regulations) taken into account in calculating the Average
     Contribution Percentage test for the Plan Year in which the excess arose,
     beginning with the Highly Compensated Employee with the largest amount of
     such contributions and continuing in descending order until all the excess
     aggregate contributions have been allocated. For purposes of the preceding
     sentence, the "largest amount" is determined after distribution of any
     excess contributions. Forfeited amounts may not be reallocated to a Highly
     Compensated Employee whose contributions for such Plan Year are reduced by
     reason of this Section.

     Code Section 401(m) and the regulations thereunder are hereby incorporated
     in this Plan by reference and the limitations of this Section shall be
     carried out in accordance with such law and regulations.

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<PAGE>

4.6  Rollover Contributions

     A.   Subject to the approval of the Plan Administrator, the Plan may accept
          an "eligible rollover distribution," as defined in Section 12.6A, with
          respect to an Employee who is a Participant, or who is expected to
          become a Participant, provided, that the contribution is received on
          or before the 60th day following its distribution from the prior
          qualified plan or individual retirement account or as a direct
          rollover from the prior qualified plan.

     B.   Any rollover contribution accepted by the Plan shall be separately
          accounted for and the Participant shall have a nonforfeitable interest
          in such account called the Participant's Rollover Account at all
          times. The Participant's Rollover Account shall be adjusted with its
          pro rata share of net earnings, losses, appreciation, or depreciation
          as of each Valuation Date. If not earlier withdrawn, the total amount
          of a Participant's Rollover Account shall be paid to the Participant
          in the same form and at the same time as the Participant's
          Employer-derived Accrued Benefit.

     C.   If an Employee has not yet become a Participant at the time he makes a
          rollover contribution to the Plan, he shall be deemed to be a
          Participant only for purposes of the investment and distribution of
          such contribution. He shall not be permitted to make Participant
          Elected Contributions or share in Employer Matching Contributions or
          Employer Profit Sharing Contributions until he has become an active
          Participant pursuant to Article III.

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             V. PARTICIPANT ACCOUNTS AND CREDITING OF CONTRIBUTIONS

5.1  Accounts

     The Plan Administrator shall establish in the name of each Participant such
     Accounts as are necessary to properly account for the types of
     contributions made on behalf of a Participant.

5.2  Allocation and Crediting of Contributions

     A.   Crediting of Participant Elected Contributions

          Employer contributions arising from a Participant's election to defer
          Compensation shall be credited to the Participant's Employee Deferral
          Account.

     B.   Crediting of Employer Matching Contributions

          Employer Matching Contributions shall be credited to the Employer
          Matching Account of the Participant for whom the Employer Matching
          Contribution is made in accordance with Section 4.2.

     C.   Allocation of the Employer's Profit Sharing Contribution

          A share of the Employer's Profit Sharing Contribution shall be
          allocated to the Employer Profit Sharing Account of a Participant who
          is in the service of the Employer on the last day of the Plan Year for
          which such contribution is made, who completes 1,000 or more Hours of
          Service during such Plan Year and who is otherwise eligible to share
          in such contribution, provided, that a Participant who retires after
          attaining Normal Retirement Age, dies, or becomes Permanently
          Disabled, as defined in Section 11.2, during the Plan Year shall share
          in the Employer's Profit Sharing Contribution for such Plan Year to
          the extent provided herein on the basis of the amount of the
          Participant's Compensation during such Plan Year prior to the
          Participant's termination of service. A Participant shall become
          eligible to share in the Employer's Profit Sharing Contributions as of
          the January 1 or July 1 coincident with or immediately following the
          Participant's Enrollment Date. In the case of a Participant who

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<PAGE>

          otherwise qualifies for a Profit Sharing Contribution but who enters
          an ineligible class of Employees during the Plan Year, or in the case
          of a Participant who first becomes eligible to share in Profit Sharing
          Contributions during such Plan Year, such Participant shall share in
          the contributions for such Plan Year to the extent of the amount of
          the Participant's Compensation paid or accrued during the time the
          Participant was in an eligible class of employees and was eligible to
          share in the Employer's Profit Sharing Contribution for such Plan
          Year.

          The amount allocated to the Employer Profit Sharing Account of a
          Participant shall be a sum as shall bear the same ratio to the total
          contribution as the ratio such Participant's Compensation bears to the
          Compensation of all Participants eligible to share in the Profit
          Sharing Contribution.

          Forfeitable amounts derived from the Employer Profit Sharing Account
          of a Participant who separates from the Employer's service shall be
          used to reduce future Employer Matching Contributions.

          If the Employer designates some portion or all of its Profit Sharing
          Contribution as a qualified nonelective contribution, the qualified
          nonelective contribution shall be allocated among the Participants who
          are Nonhighly Compensated Employees based on the ratio that each such
          Participant's Compensation for the Plan Year bears to the Compensation
          of all such Participants for the Plan Year.

5.3  Valuation of Assets

     As of each Valuation Date, the Trustee shall value the assets of the Trust
     at the then current fair market value.

5.4  Adjustment of Participants' Accounts

     As of each Valuation Date, the net income (or loss) of the Trust since the
     immediately preceding Valuation Date shall be determined. Net income (or
     loss) of the Trust includes the increase (or decrease) in the fair market
     value of Trust Fund assets, interest income, dividends and other income and
     gains (or losses) attributable to Trust Fund assets since the immediately
     preceding Valuation Date, reduced by any expenses charged to the Trust Fund
     for the period since the immediately preceding Valuation Date.

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<PAGE>

      The net income (or loss) of the Trust will be determined separately for
      each Investment Fund and allocated among the Accounts of the Participants
      in proportion to the respective balances of such Accounts invested in each
      such Investment Fund.

5.5   Limitation on Allocations

      Notwithstanding any other provision of the Plan, the annual addition to a
      Participant's Accounts for a Limitation Year shall not exceed an amount
      equal to:

      A.   Limitation. The lesser of:

           1.   $30,000, as adjusted pursuant to Code Section 415(d) for Plan
                Years beginning on and after January 1, 1995, or

           2.   Twenty-five percent (25%) of the compensation paid by the
                Employer to the Participant during the Limitation Year.
                Effective January 1, 1998, for purposes of this Section 5.5,
                compensation means Compensation as defined in Section 2.7.

      B.   Additions

           For purposes of imposing the limitations of Code Section 415, "annual
           additions" shall mean the sum of the following credited to the
           Participant for the Limitation Year:

           1.   Employer contributions;

           2.   The Participant's contributions other than a rollover
                contribution;

           3.   Forfeitures;

           4.   Amounts allocated to a separate account under a pension or
                annuity plan for a key employee (as defined under Code Section
                416(i)) in Plan Years beginning after March 31, 1984, to provide
                post-retirement medical benefits to such Participant and the
                Participant's spouse and dependents, and amounts paid after
                December 31, 1985, in tax years ending after that date to a
                separate account under a welfare benefit plan (as defined under
                Code Section 419(e)) of the Employer for a Participant who is or
                was a key employee (as defined under Code Section 416(i)) to
                provide post-retirement medical benefits to such Participant;
                and

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<PAGE>

           5.   Amounts allocated to a separate account under a pension or
                annuity plan for a Participant and the Participant's spouse and
                dependents, under which benefits described in Code Section
                401(h) are payable.

      C.   Aggregation of Plans

           All defined contribution plans maintained by the Employer, including
           voluntary employee contribution accounts in a defined benefit plan,
           Key employee accounts under a welfare benefit plan described in Code
           Section 419, and any Employer contributions allocated to an
           individual retirement account, shall be treated as a single plan for
           purposes of the limitations of this Section.

      D.   Excess Addition

           If the annual addition to the Account of a Participant exceeds the
           limitation of this Section 5.5 during a Plan Year, then such excess
           amount shall be eliminated first by returning, to the extent
           necessary to satisfy these limitations, the Participant's Participant
           Elected Contributions for such Plan Year, as adjusted for allocable
           income (together with forfeiting any related Matching Contribution),
           and then (if the limitations of this Section are still not satisfied)
           by reducing, to the extent necessary to satisfy these limitations,
           the Employer's contribution to the Participant's Account made for any
           other reason. The amount of the reduction (hereafter called the
           excess amount) shall be used to reduce the Employer's contribution
           for the next Plan Year, and each succeeding Plan Year, for that
           Participant if covered by the Plan as of the end of such Plan Year.
           If the Participant is not covered by the Plan as of the end of the
           Plan Year, then the excess amount shall be held unallocated in a
           suspense account for the Plan Year and allocated and reallocated in
           the next Plan Year, to the extent possible, to reduce the Employer's
           contribution for such Plan Year. If a suspense account is in
           existence during a Plan Year, other than the Plan Year in which it is
           established, the Employer shall make no contribution to the Plan
           until all amounts in the suspense account have been allocated and
           reallocated to Participants. No investment gains or losses or other
           income or expense shall be allocated to a suspense account. In the
           event a suspense account is in existence at the time the Plan
           terminates, any amount in the suspense account that cannot then be
           allocated to Participants shall be returned to the Employer.

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<PAGE>

5.6   Controlled Groups

      In applying the limitations of Section 5.5, the Employer and its
      Affiliates shall be treated as a single employer.

5.7   Protection of Accrued Benefits

      With the exception of an amendment described under Code Section 412(c)(8),
      no amendment to the Plan shall reduce the Accrued Benefit of a Participant
      determined as of the date immediately preceding the adoption of the
      amendment. In the event that an amendment either directly or indirectly
      reduces or restricts a protected benefit under Code Section 411(d)(6),
      such benefit for a Participant is presumed as of the later of the adoption
      date or the effective date of the amendment. In the case of an amendment
      adopted after July 30, 1984 that, with respect to benefits attributable to
      service before the amendment, eliminates or reduces an early retirement
      benefit or a retirement-type subsidy (as defined by the Secretary of the
      Treasury), such amendment shall not reduce the Accrued Benefit of a
      Participant, determined immediately prior to the adoption of the amendment
      and determined without regard to the amendment, if the Participant, either
      before or after the amendment but before termination of service, satisfies
      the preamendment requirements for the benefit. An amendment described in
      the preceding sentence shall not eliminate optional benefit forms (except
      as permitted by the Secretary of the Treasury) with respect to the Accrued
      Benefit of a Participant accrued as of the date immediately preceding the
      adoption of the amendment. The availability of any protected benefit of a
      Participant provided under the Plan, as defined in Code Section 411(d)(6),
      shall not be subject to the Employer's consent or discretion.

5.8   Title to Assets in Trustee

      Title to all assets under the Plan shall be vested in the Trustee which
      shall hold the Trust Fund and the income as a part thereof and make
      payments therefrom as provided in the Plan.

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<PAGE>

                              VI. INVESTMENT FUNDS

6.1   Separate Funds

      The Plan Administrator, in its discretion, shall select Investment Funds
      to be offered to Participants for investment of their Accounts, and the
      Plan Administrator shall direct the Trustee to establish accounts for the
      Investment Funds as determined by the Plan Administrator.

6.2   Participant Direction

      In the event that the Plan Administrator authorizes the use of more than
      one Investment Fund, each Participant shall designate the percentage of
      the future contributions to be allocated to his Accounts that will be
      invested in each of the Investment Funds available under the Plan. Any
      such designation shall be made in such increments, in such manner and
      pursuant to such other rules and limitations as the Plan Administrator
      shall prescribe. A Participant's investment designation shall remain in
      effect until changed by the Participant (or the Beneficiary, if
      applicable). A Participant (or Beneficiary, as applicable) may change his
      investment designation with respect to the future contributions to be
      allocated to, and/or the existing balances in, his Accounts at such times,
      in such increments and pursuant to such other rules and limitations as the
      Plan Administrator shall prescribe.

6.3   Investment Results

      As of each Valuation Date, the investment results obtained in the
Investment Funds shall be allocated only to the Account balances of Participants
who have invested in the fund.

6.4   Voting of Stock Held in Investment Funds

      With respect to each Participant's investment in any Investment Fund,
other than the Immunex Corporation Common Stock Fund, the Trustee shall vote the
number of shares credited to each Participant's Account, in each case, in a
manner that the Trustee believes to be consistent with its fiduciary duties
under section 404 of ERISA.

6.5   Voting of Employer Stock

      With respect to each Participant's investment in the Immunex Corporation
Common Stock Fund, before each annual or special meeting of the stockholders of
the

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<PAGE>

Employer, the Employer will furnish such Participant with a copy of the proxy
solicitation material for such meeting, together with a form addressed to the
Trustee requesting the Participant's confidential instructions on how the shares
of Immunex Corporation common stock ("Shares") allocated to the Participant's
Account should be voted on each matter to come before the meeting. The number of
Shares allocated to a Participant's Account will be determined by multiplying
the number of Shares held in the Immunex Corporation Common Stock Fund as of the
applicable record date by a fraction, the numerator of which is the number of
units of such Fund held in the Participant's Account as of the applicable record
date and the denominator of which is the total number of outstanding units of
such Fund as of such date. Upon receipt of such instructions, the Trustee shall
vote Shares allocated to each Participant's Account (including fractional as
well as whole Shares) in accordance with timely directions of such Participant;
provided, that a failure of a Participant to timely and affirmatively direct the
manner in which Shares allocated to the Participant's Account are to be voted
shall be deemed for purposes of this Section to be an affirmative direction to
abstain from voting.

6.6   Tender of Employer Stock

      The Trustee shall, with respect to Shares allocated to that portion of
each Participant's Account invested in the Immunex Corporation Common Stock
Fund, act in response to any tender offer or exchange offer for Shares commenced
by a person or persons, including, but not limited to, a tender offer or
exchange offer within the meaning of the Securities Exchange Act of 1934, as
amended from time to time (all such tender or exchange offers collectively, a
"tender offer"), in accordance with timely directions of such Participant;
provided, that a failure of a Participant to timely and affirmatively direct the
manner in which the Trustee is to act in response to a tender offer with respect
to Shares allocated to the Participant's Account shall be deemed for purposes of
this Section to be an affirmative direction not to take action with respect to
such Shares. For purposes of determining the number of Shares to be the subject
of any particular response to a tender offer, the Trustee shall use the nearest
practicable date as determined by the Trustee. The number of Shares allocated to
a Participant's Account will be determined by multiplying the number of Shares
held in the Immunex Corporation Common Stock Fund as of the relevant date by a
fraction, the numerator of which is the number of units of such Fund held in the
Participant's Account as of such date and the denominator of which is the total
number of outstanding units of such Fund as of such date. The Employer and the
Trustee each shall use its best efforts to timely distribute or to cause to be
distributed to each Participant such information as is being distributed to
other stockholders of the Employer in connection with any such tender offer.

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<PAGE>

                             VII. PARTICIPANT LOANS

The Plan Administrator, upon the application of a Participant, may direct the
Trustee to make a loan or loans to such Participant. The Plan Administrator
shall follow a uniform and nondiscriminatory policy in approving such loans and
loans shall be made available to Participants on a reasonably equivalent basis.

7.1   Loans to Participants

      A.  Availability of Loans

          Upon application by a Participant, the Plan Administrator may direct
          the Trustee to make a loan to the Participant from the vested balances
          in the Participant's Employee Deferral Account, Rollover Account and
          Employer Matching Account. Such borrowing rules must be formulated and
          administered so that the requirements of Code Section 72(p) for
          non-taxable loans, the applicable Department of Labor regulations on
          plan loans, and the following provisions of this Section 7.1 are
          satisfied. Any loan hereunder will bear a reasonable rate of interest
          and will be evidenced by a promissory note signed by the Participant
          in such form as the Plan Administrator may require. The amount of any
          such loan will be withdrawn from the vested balances in the
          Participant's Employee Deferral Account, Rollover Account and Employer
          Matching Account and from the Investment Fund or Funds in which such
          Accounts are invested in the manner specified in the Plan
          Administrator's borrowing rules.

      B.  Plan Administrator's Borrowing Rules

          The Plan Administrator may adopt borrowing rules for loans hereunder
          and may revise such rules from time to time. The rules may contain
          such requirements pertaining to loans as the Plan Administrator deems
          necessary or desirable and that are not specified herein. The
          borrowing rules may govern the procedures and cut-off dates for
          applying for loans hereunder and the terms of such loans, including
          (i) the number of loans that a Participant may request in any year and
          the number of loans that may be outstanding at any time to a
          Participant, (ii) any restrictions on reborrowing not stated in this
          Section 7.1, (iii) the interest rate in effect from time to time for
          loans or the method of ascertaining such interest rate, and (iv) the
          repayment schedule for loans or the method for determining the
          repayment schedule.

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<PAGE>

      C.  Amount of Loans

          The minimum loan amount is $1,000 or such lesser amount as the Plan
          Administrator may from time to time set forth in its borrowing rules.
          The maximum aggregate loan amount is based upon the vested balances in
          the Participant's Accounts. No Participant loan will exceed the
          smallest of (i) the amount of the vested balances in the Participant's
          Employee Deferral Account, Rollover Account and Employer Matching
          Account, (ii) one-half of the Participant's vested Account balances,
          or (iii) $50,000 (reduced by the highest outstanding loan balance to
          the Participant during the 12 months preceding the loan). For purposes
          of applying such limits, Account values as the Valuation Date
          coincident with or immediately preceding the date on which the loan is
          made will be used.

      D.  Maximum Repayment Period

          1.   Other Than Residential Loans

               Except as provided in paragraph 2 immediately below, the maximum
               term of a loan will be 5 years (provided that the Plan
               Administrator may establish a shorter repayment period for small
               loans).

          2.   Residential Loans

               If a Participant requests a loan for the acquisition or
               construction of the Participant's principal residence, the
               repayment period will be determined by reference to bank loans
               for the same purpose but may not exceed 10 years; provided,
               however, that effective January 1, 2002, loans described in this
               paragraph 2 that are transferred (or rolled over) to this Plan
               from another plan shall retain the original term of such loan,
               even if it exceeds 10 years.

      E.  Security for Repayment

               Each loan hereunder will be a Participant-directed investment for
               the benefit of the Participant requesting such loan; accordingly,
               any default in the repayment of principal or interest of any loan
               hereunder will reduce the amount available for distribution to
               such Participant (or the Participant's Beneficiary). Thus, any
               loan hereunder will be secured by up to 50 percent of the vested
               amount in the Participant's Accounts. The

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<PAGE>

          Plan Administrator acting under its borrowing rules may require other
          security for repayment of a loan in any instance. A Participant
          receiving a loan must execute such instruments as the Plan
          Administrator requests and must pay any fees for filings required by
          the Plan Administrator to perfect any security interest in the
          Participant's Accounts or other security.

      F.  Repayment

          The Plan Administrator may require a Participant to execute an
          agreement to repay the principal and interest of a loan through
          regular payroll deduction payments from the Participant's
          compensation. The Plan Administrator may establish back-up repayment
          procedures for Participants who do not make payroll deduction
          repayment. Except as otherwise may be permitted under Treasury
          regulations, any repayment procedure must provide for substantially
          level amortization payments made quarterly or more frequently. Any
          loan hereunder may be prepaid, in whole or in part, at any time
          without penalty. If a Participant's service as an Employee is
          terminated for any reason, the entire unpaid principal and interest of
          any loan then outstanding to such Participant will become immediately
          due and payable.

      G.  Action Upon Default

          If a Participant defaults on any payment of interest or principal of a
          loan hereunder or defaults upon any other obligation relating to such
          loan, the Plan Administrator may take (or direct the Trustee to take)
          such action or actions as it determines to be necessary to protect the
          interests of the Plan. Such actions may include commencing legal
          proceedings against the Participant, or foreclosing on any security
          interest in the Participant's Accounts or other security given in
          connection with a loan hereunder; however, the Plan Administrator will
          not direct foreclosure on the Participant's Employee Deferral Account
          at a time when the Participant would not be entitled to receive a
          distribution or withdrawal from such Account.

      H.  Distribution to Participant With Loan

          In the case of any Participant with a loan outstanding hereunder, the
          amount available for distribution to such Participant (or such
          Participant's Beneficiary) will consist of the portion of his Accounts
          invested in the Investment Funds of the Trust Fund. In addition, the

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<PAGE>

          Participant's note will be distributed to the Participant (or the
          Participant's Beneficiary), and the Trustee will report the value of
          the note for income tax purposes as the amount of unpaid principal and
          interest due thereon at the date of distribution.

7.2   Accounting for Loans

      A.  Source of Loan

          The Plan Administrator will establish procedures and ordering rules
          for liquidating the Participant's Accounts to make a loan to him.

      B.  Loan Account

          The Plan Administrator will establish and maintain a loan account for
          each borrowing Participant. The unpaid principal and accrued but
          unpaid interest on the loans to a Participant will be reflected for
          Plan accounting purposes in the Participant's loan account. Repayments
          by the Participant will be credited to the Participant's loan account.
          The Plan Administrator will establish uniform procedures for
          transferring repayment amounts from his loan account to the
          Participant's other accounts.

Immunex Corporation Profit Sharing 401(k) Plan and Trust              Page VII-4

<PAGE>

                          VIII. NONFORFEITABLE BENEFITS

8.1   Nonforfeitable Interest

      A Participant shall have a nonforfeitable interest in the Participant's
      Accounts based on the Participant's Years of Service for vesting. The
      Participant's Years of Service shall be determined in accordance with
      Section 8.2, and the Participant's nonforfeitable interest shall be
      determined as follows:

      A.  Employee Deferral Account and Rollover Account

          A Participant shall have a nonforfeitable interest in the
          Participant's Employee Deferral Account and Rollover Account at all
          times.

      B.  Employer Matching Account and Employer Profit Sharing Account

          A Participant's nonforfeitable interest in the Participant's Employer
          Matching Account and Employer Profit Sharing Account shall be
          determined under the following schedule:

         Completed Years                           Nonforfeitable
           of Service                                Percentage

          Less than 1                                     0
        1 but less than 2                                20
        2 but less than 3                                40
        3 but less than 4                                60
        4 but less than 5                                80
          5 or more                                     100

          In the event the Employer designates some part or all of a Profit
          Sharing Contribution for a Plan Year as a qualified nonelective
          contribution, a Participant to whom such a contribution is allocated
          shall have nonforfeitable interest in such contribution at all times.

8.2   Years of Service

      The following rules shall be applied in determining the number of a
      Participant's Years of Service using the Vesting Computation Period to
      credit Years of Service and One-Year Breaks in Service. All of an
      Employee's Years

Immunex Corporation Profit Sharing 401(k) Plan and Trust             Page VIII-1

<PAGE>

     of Service with the Employer shall be counted except the following Years of
     Service shall be disregarded:

     A.   Years of Service prior to a One-Year Break in Service until the
          Employee completes a Year of Service following the Participant's
          return to the service of the Employer.

     B.   Years of Service completed prior to a One-Year Break in Service if the
          Employee does not have any nonforfeitable interest under the Plan to
          an Accrued Benefit derived from Employer contributions and the number
          of the Employee's consecutive One-Year Breaks in Service equals or
          exceeds the greater of five (5) or the aggregate number of the
          Employee's Years of Service prior to such Break; provided, that in the
          case of Plan Years beginning prior to January 1, 1985, a nonvested
          Employee's Years of Service prior to a One-Year Break in Service
          (incurred in a Plan Year beginning prior to 1985) shall not be counted
          if the number of the Employee's consecutive One-Year Breaks in Service
          equals or exceeds the aggregate number of the Employee's Years of
          Service prior to such Break. In applying the rules of this paragraph,
          if any Years of Service are disregarded by reason of any earlier
          One-Year Break in Service, such Years of Service shall not be
          aggregated when determining whether Years of Service are to be
          disregarded by reason of a subsequent One-Year Break in Service.

8.3  No Increase in Pre-break Vesting

     In the case of a Participant who incurs five (5) consecutive One-Year
     Breaks in Service, Years of Service completed by such Participant after
     such Break period shall not be counted to increase the Participant's
     nonforfeitable interest in the Participant's Accounts as determined prior
     to such Break period.

8.4  Forfeitable Interests

     Upon separation from the Employer's service for any reason, a Participant's
     forfeitable interest in the Participant's Accrued Benefit shall be
     forfeited in accordance with the following rules, whichever is applicable.

Immunex Corporation Profit Sharing 401(k) Plan and Trust             Page VIII-2

<PAGE>

     A.   Zero Percent Vested

          In the event a Participant's service with the Employer terminates and
          such Participant does not have any nonforfeitable interest in the
          Participant's Accrued Benefit, the Participant shall be deemed to have
          received a distribution of such nonforfeitable Accrued Benefit on his
          termination date and the forfeitable portion of the Accrued Benefit
          shall be forfeited at the time of the Participant's separation from
          service. A Participant who has no vested interest will be deemed
          cashed out from the Plan. If a Participant is deemed to receive a
          distribution in accordance with this paragraph and the Participant
          resumes service with the Employer or an Affiliate before the date on
          which the Participant incurs five consecutive One-Year Breaks in
          Service, the amount of the forfeited Accrued Benefit shall be
          restored.

     B.   Partially Vested

          1.   Five-Year Break in Service

               In the event a Participant's service with the Employer and its
               Affiliates terminates and such Participant has a nonforfeitable
               interest in the Participant's Accrued Benefit but is not paid the
               entire nonforfeitable portion of the Participant's Account, a
               separate account shall be established for the Participant's
               remaining Accrued Benefit and the forfeitable interest the
               Participant shall be forfeited as of the end of the Plan Year in
               which the Participant incurs five (5) consecutive One-Year Breaks
               in Service. The Participant's nonforfeitable interest in the
               Participant's separate Account at any time prior to incurring 5
               consecutive One-Year Breaks in Service shall be an amount "X"
               determined under the formula X = P(AB + (R x D)) - (R x D), where
               P is the vested percentage at the relevant time; AB is the
               Account balance at the relevant time; D is the amount of the
               distribution; R is the ratio of the Account balance at the
               relevant time to the Account balance after distribution; and the
               relevant time is the time at which, under the Plan, the vested
               percentage in the Account cannot increase.

          2.   Cash Out Rule

               In the event a Participant's service with the Employer and its
               Affiliates terminates and such Participant is paid the
               Participant's

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<PAGE>

               entire nonforfeitable interest prior to incurring 5 consecutive
               One-Year Breaks in Service, the forfeitable interest of the
               Participant shall be forfeited at the time the payment is made.
               If the Participant returns to the Employer's (or an Affiliate's)
               service before incurring 5 consecutive One-Year Breaks in Service
               and repays to the Plan the full amount of the earlier
               distribution, the forfeited amount, unadjusted by any investment
               increases or decreases, shall be restored to the Participant's
               Account. To obtain a restoration of a forfeited amount, the
               Participant's repayment must be made before the earlier of the
               date on which the Participant incurs five consecutive One-Year
               Breaks in Service or the end of the five year period beginning
               with the date on which the Participant resumes employment with
               the Employer or an Affiliate. If the Participant's earlier
               distribution was made for any reason other than separation of
               service with the Employer and its Affiliates, the forfeited
               amount shall be restored only if the Participant repays the
               earlier distribution before the date five years after the date of
               the distribution. A Participant whose entire nonforfeitable
               interest has been distributed from the Plan will be deemed cashed
               out from the Plan.

8.5  Distribution to Separated Participants

     In the case of a Participant who separates from the service of the Employer
     and its Affiliates, the Participant's nonforfeitable interest in the
     Participant's Accounts shall be payable in accordance with the provisions
     of Article XII.

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<PAGE>

                                 IX. RETIREMENT

9.1   Retirement Age and Benefit

      A.  Normal Retirement

          A Participant shall have a nonforfeitable interest in the
          Participant's Accrued Benefit upon attaining Normal Retirement Age.
          Payment of the Participant's Accounts shall be made in accordance with
          the provisions of Article XII.

      B.  Postponed Retirement

          A Participant may not be required to retire involuntarily under this
          Plan simply because the Participant attains Normal Retirement Age.
          Subject to Section 12.2A, no payment of a Participant's Accounts shall
          be made under the Plan until a Participant actually retires and ceases
          employment. Upon actual retirement, payment of the Participant's
          Accounts shall be made in accordance with the provisions of Article
          XII.

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<PAGE>

                                X. DEATH BENEFIT

10.1      Death of Participant

          A Participant who dies while in the service of the Employer shall be
          100 percent vested in the Participant's Accounts upon the
          Participant's death. Upon a Participant's death, the nonforfeitable
          portion of the Participant's Accounts shall be payable to the
          Participant's Surviving Spouse, or the Participant's designated
          Beneficiary if the Participant has no Surviving Spouse at the time of
          death or the Spouse consents to the designation of a Beneficiary other
          than the Surviving Spouse. The designation of a Beneficiary to whom
          the Spouse has consented shall not be changed without the Spouse's
          consent to such change unless the Spouse's earlier consent expressly
          permits designations by the Participant without any requirement of
          further consent by the Spouse. A Spouse's consent must be in writing,
          it must acknowledge the effect of the Beneficiary designation and it
          must be witnessed by a notary public or a Plan representative. A
          Spouse's consent to a Beneficiary designation as provided for under
          this Section is effective only with respect to that Spouse. Payment of
          the death benefit shall be made in accordance with the provisions of
          Article XII, provided that the Surviving Spouse may require that the
          payment be made within a reasonable time following the Participant's
          death.

10.2      Payments Upon Failure to Designate Beneficiary

          Any portion of the amount payable that is undisposed of because of the
          failure to designate a Beneficiary or the failure of the Beneficiary
          to survive the Participant shall be paid in order of survivorship to:

          A.   The Participant's Surviving Spouse;

          B.   The Participant's descendants, per stirpes; and

          C.   If none are surviving, the Participant's estate.

          Notwithstanding the above, if the Plan Administrator is unable to
          locate any of the persons listed in (A) or (B) within three (3)
          months, the Plan Administrator may pay the death benefits to the
          Participant's estate.

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<PAGE>

                             XI.  DISABILITY BENEFIT

11.1 Payment Due

     If a Participant becomes Permanently Disabled while in the service of the
     Employer, the Participant shall be 100 percent vested in the Participant's
     Accounts as of the date of the Participant's disability. Payment of the
     Participant's entire interest shall be made in accordance with the
     provisions of Article XII.

11.2 "Permanently Disabled"

     "Permanently Disabled" means that the Participant is unable by reason of
     any medically determinable physical or mental impairment to substantially
     perform the regular material duties of the same occupations for which the
     Participant has been employed by the Employer, and such disability is
     expected to be of long, continued and indefinite duration. Permanent
     disability shall be established by the certification of a physician,
     selected by the Participant and approved by the Plan Administrator that the
     Participant has suffered a permanent disability, or if the physician
     selected by the Participant shall not be approved by the Plan
     Administrator, by a majority of three physicians, one selected by the
     Participant (or the Participant's Spouse, child, parent or legal
     representative in the event of the Participant's inability to select a
     physician), one by the Plan Administrator, and the third by the two
     physicians selected by the Participant and the Plan Administrator. The
     decision of the majority of such three physicians shall be final and
     conclusive.

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<PAGE>

                       XII.  DISTRIBUTIONS AND WITHDRAWALS

12.1 Distribution of Benefits

     A.   Forms of Distribution

          Subject to subsection C below, any amounts payable under the terms of
          the Plan with respect to a Participant who retires after attaining
          Normal Retirement Age, becomes Permanently Disabled or dies shall, at
          the election of the Participant or Beneficiary (as applicable), be
          paid as a single-sum distribution of cash, or in a series of payments
          over a period not to extend beyond the life expectancy of the
          Participant (or the Beneficiary, as applicable) or the joint life
          expectancy of the Participant and the Participant's Beneficiary. Any
          amounts payable under the terms of the Plan with respect to a
          Participant who separates from service for any other reason shall be
          paid as a single-sum distribution of cash. No annuities shall be
          payable from the Plan. Each optional form of benefit offered under the
          Plan shall be available to all Participants on a nondiscriminatory
          basis. Notwithstanding the foregoing, if the Plan Administrator
          establishes an Investment Fund that is designed to invest primarily in
          the common stock of Immunex Corporation, a Participant (or
          Beneficiary, as applicable) may elect to receive such whole shares of
          Immunex Corporation common stock as are allocated to that portion of
          the Participant's vested Accounts that is invested in such Investment
          Fund (with cash for any fractional shares), in lieu of receiving cash
          for such portion of the Participant's Accounts.

     B.   Time of Distribution

          1.   Distribution Dates

               Subject to paragraph 2 of this subsection B, subsection C below
               and Section 12.2, benefits due to a Participant or Beneficiary,
               as applicable, shall be paid or commence to be paid within an
               administratively reasonable time following the Valuation Date
               elected by the Participant or Beneficiary, as applicable. A
               Participant or Beneficiary may elect to commence distributions as
               of any Valuation Date coinciding with or following the
               Participant's separation from service with the Employer and its
               Affiliates. In the case of a payment to a Participant, the
               payment shall not be made without the consent of the Participant,
               to the

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<PAGE>

               extent required by law, if the value of the Participant's
               nonforfeitable interest in the Participant's Accounts exceeds
               $5,000 as of the date of distribution.

          2.   Consent to Distribution

               Unless a Participant elects in writing to receive the
               Participant's benefit at a later date, payment to a Participant
               shall be made no later than sixty (60) days after the close of
               the Plan Year in which the latest of the following events occurs:

               a.   The Participant attains age sixty-five (65);

               b.   The 10th anniversary of the date on which the Participant
                    first became a Participant; or

               c.   The termination of the Participant's service with the
                    Employer.

     C.   Small Benefit Cash-Out

          If the Participant's nonforfeitable interest in his Accounts does not
          exceed $5,000 as of the date of distribution, that interest shall be
          distributed as a lump sum within an administratively reasonable time
          following the Valuation Date coinciding with or immediately following
          the Participant's separation from service with the Employer and its
          Affiliates.

     D.   Valuation of Accounts for Distribution

          For purposes of determining the value of a Participant's Accounts
          under this Section, the value shall be determined as of the Valuation
          Date immediately preceding the date of distribution.

12.2 Required Distributions

     Notwithstanding any other provision of this Plan to the contrary, effective
     for Plan Years beginning on and after January 1, 1997, the following shall
     apply:

     A.   The entire interest of a Participant shall be distributed commencing
          no later than the Participant's Required Beginning Date.

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<PAGE>

     B.   The Participant's interest shall be distributed over a period that
          does not exceed the life expectancy of the Participant (or the
          Beneficiary) or the life expectancy of the Participant and the
          Participant's designated Beneficiary, provided, that if the
          distributions are for a period measured by the life expectancy of the
          Participant or the joint life expectancy of the Participant and the
          Participant's Spouse, if applicable, such life expectancies shall be
          recalculated annually, if the Participant so elects. If the
          Participant's designated Beneficiary is someone other than his Spouse,
          then the Participant's life expectancy may be recalculated, but the
          Beneficiary's may not. Distributions to the Participant or the
          Participant and the Participant's designated Beneficiary shall meet
          the minimum annual distribution requirements and the incidental death
          benefit rules of Code Section 401(a)(9) and the regulations
          thereunder, including Treasury Regulation (S) 1.401(a)(9)-2, which are
          incorporated herein by reference.

          Notwithstanding any provision of the Plan to the contrary, with
          respect to distributions under the Plan made for calendar years
          beginning on or after January 1, 2001, the Plan will apply the minimum
          distribution requirements of Code Section 401(a)(9) in accordance with
          the regulations under Code Section 401(a)(9) that were proposed on
          January 17, 2001, notwithstanding any provision of the Plan to the
          contrary. This amendment shall continue in effect until the end of the
          last calendar year beginning before the effective date of final
          regulations under Code Section 401(a)(9) or such other date as may be
          specified in guidance published by the Internal Revenue Service.

     C.   If payments have commenced to the Participant and the Participant dies
          before the Participant's entire interest is distributed, the
          Participant's remaining interest shall be distributed to the
          Participant's Beneficiary at least as rapidly as under the method of
          distribution to the Participant as of the date of the Participant's
          death.

     D.   If a Participant dies before distribution of the Participant's
          interest has commenced, the Participant's entire interest shall be
          distributed by December 31 of the calendar year containing the fifth
          anniversary of the Participant's death, provided, that if the
          Participant has designated a Beneficiary to receive a part or all of
          the Participant's interest and if payment to the Beneficiary commences
          no later than December 31 of the calendar year following the year of
          the Participant's death, the portion payable to such Beneficiary may
          be paid over a period that does

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<PAGE>

          not exceed the Beneficiary's life expectancy. In the event the
          Participant's designated Beneficiary is the Participant's Spouse,
          payment to the Spouse need not commence earlier than the later of
          December 31 of the year in which the Participant would have attained
          age seventy and one-half (70-1/2) or December 31 of the year following
          the year of the Participant's death. If a deceased Participant's
          designated Beneficiary is the Participant's Spouse and the Spouse dies
          before payments commence, the Participant's entire interest shall be
          distributed by applying the rules of this paragraph as though the
          deceased Spouse were the Participant.

12.3 Distributions to Minors and Incompetents

     If any Participant or Beneficiary entitled to receive benefits hereunder is
     a minor or, in the judgment of the Plan Administrator, unable to take care
     of his affairs because of mental condition, illness or accident, any
     payment due such person may, in the sole discretion of the Plan
     Administrator (unless prior claim therefor shall have been made by a
     qualified guardian or other legal representative), be paid for the benefit
     of such Participant or Beneficiary: (a) to such person's legal
     representative appointed by proceedings satisfactory to the Plan
     Administrator; (b) to such person (other than a minor) directly even though
     he is not then able to exercise control over such payment; and/or (c) to
     any custodian under the Uniform Gifts to Minors Act or similar statutes or
     guardian of such person or of his property with whom such person is making
     his home. Neither the Trustee, the Plan Administrator nor the Employer
     shall be required to see to the application of any such distribution so
     made to any of said persons, but said person's receipt shall be a full
     discharge of the Trustee's, the Plan Administrator's and the Employer's
     duties.

12.4 Qualified Domestic Relations Orders

     A.   Distributions

          In the event a person (hereafter called the "alternate payee") is
          designated by a qualified domestic relations order, as defined under
          Code Section 414(p), as having a right to receive all, or a portion
          of, the benefits payable under the Plan to a Participant, payment to
          the alternate payee may, to the extent provided by such order, begin
          at a time not permitted for distributions to the Participant. Payment
          to the alternate payee may be made as though the Participant had
          retired on the date on which the order requires payment to begin
          considering the present value

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<PAGE>

          of benefits accrued by the Participant up to such date (but
          disregarding an Employer subsidy for early retirement). Payment may be
          made in any form permitted by the Plan other than in the form of a
          joint and survivor annuity with respect to the alternate payee and the
          alternate payee's spouse.

     B.   Separate Account Period

          If it is being determined whether a domestic relations order received
          in connection with a Participant is a qualified domestic relations
          order, the Plan Administrator shall separately account for the amounts
          that would have been paid to the alternate payee during the period of
          determination if the order was a qualified one. If the order is
          determined to be a qualified order at any time during the eighteen
          (18) month period beginning on the date on which the first payment
          would be required to be made under the qualified domestic relations
          order, the Plan Administrator shall pay the segregated amounts,
          including interest thereon, to the persons entitled to the amounts
          under the order. If it is determined that the order is not a qualified
          order or if at the end of the eighteen (18) month period it is still
          undetermined whether the order is a qualified order, the segregated
          amounts, including interest thereon, shall be paid to the persons who
          would have been entitled to the payments had there been no order. In
          the event it is determined that the order is a qualified order only
          after the eighteen (18) month period has elapsed, the application of
          the order shall be applied prospectively only, beginning as of such
          determination date.

     C.   Suspension of Benefits

          Notwithstanding any provision of the Plan to the contrary, in
          accordance with procedures established by the Plan Administrator, the
          Plan Administrator may temporarily suspend a Participant's right to
          borrow or withdraw from his Account or obtain a distribution from his
          Account, if (i) the Plan Administrator receives a domestic relations
          order and the Participant's Account is a source of the payment for
          such domestic relations order, or (ii) if the Plan Administrator
          receives notice that a domestic relations order is being sought by the
          Participant, his spouse, former spouse, child or other dependent (as
          defined in Code Section 152) and the Participant's Account is a source
          of the payment for such domestic relations order. Such suspension may
          continue for a reasonable period of time (as determined by the
          Administrator) which

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<PAGE>

            may include the period of time the Plan Administrator, a court of
            competent jurisdiction or other appropriate person is determining
            whether the domestic relations order qualifies as a QDRO.

12.5   Hardship Distributions

       The Plan will allow hardship distributions. A distribution of all or a
       portion of the Participant's Elected Contributions Account (other than
       earnings credited thereto after December 31, 1988) and the Participant's
       Rollover Account may be made to a Participant upon the Participant's
       request if it is established that the Participant has an immediate and
       heavy financial need and the distribution is necessary to satisfy such
       need. The Plan Administrator shall establish the existence of the
       Participant's immediate and heavy financial need and the Participant's
       necessity for a distribution to satisfy such need by applying the
       following standards:

       A.   Immediate and Heavy Financial Need

            A need will be deemed to be an immediate and heavy financial need if
            it is to pay for one or more of the following:

            1.   Uninsured medical expenses described in Code Section 213(d)
                 incurred by the Participant, the Participant's Spouse, or any
                 dependent of the Participant (a dependent shall be determined
                 under Code Section 152) or necessary for such persons to
                 receive medical care, as defined in Code Section 213(d);

            2.   Purchase (excluding mortgage payments) of a principal residence
                 for the Participant;

            3.   Payment of tuition and related educational fees for the next 12
                 months of post-secondary education for the Participant or the
                 Participant's Spouse, children or dependents;

            4.   The need to prevent the eviction of the Participant from the
                 Participant's principal residence or foreclosure on the
                 mortgage of the Participant's principal residence; or

            5.   Any other reason recognized to constitute an immediate and
                 heavy financial need by the Commissioner of the Internal
                 Revenue Service in a revenue ruling, notice or other document
                 of general applicability. A need otherwise determined to
                 constitute

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<PAGE>

            an immediate and heavy financial need will not fail to be such a
            need merely because the need is foreseeable or voluntarily incurred
            by the Participant.

B.     Distribution Necessary to Satisfy the Financial Need

       A distribution will be necessary to satisfy the immediate and heavy
       financial need only if all of the following requirements are satisfied:

       1.   The amount distributed does not exceed the amount of the heavy and
            immediate financial need, increased by any amounts necessary to pay
            any federal, state or local income taxes or penalties reasonably
            anticipated to result from the distribution;

       2.   The Participant has obtained all distributions (other than hardship
            distributions) and all nontaxable loans currently available to the
            Participant under the Plan and under all other qualified plans
            maintained by the Employer; and

       3.   The requirements of subsection C immediately below are satisfied.

C.     Restrictions

       The following restrictions will apply to a Member who receives a hardship
       withdrawal:

       1.   Upon receiving a distribution under this Section 12.5, the
            Participant's elective contributions (e.g., Participant Elected
            Contributions) and employee contributions under this Plan and all
            other plans maintained by the Employer or an Affiliate will be
            suspended for at least 12 consecutive months; and

       2.   A Participant who receives a distribution under this Section may not
            make elective contributions (e.g., Participant Elected
            Contributions) under the Plan or any other plans maintained by the
            Employer or an Affiliate for the Participant's taxable year
            (immediately following the taxable year of the hardship
            distribution) in excess of the Section 402(g) Limit for such taxable
            year less the amount of the Participant's elective contributions for
            the taxable year of the hardship distribution.

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<PAGE>

       D.   Additional Rules

            The following rules shall apply to each request for a hardship
            distribution by a Participant.

            1.   The Participant's request for a hardship distribution shall be
                 made on such forms as are provided by the Plan Administrator
                 from time to time and the Participant shall furnish the Plan
                 Administrator with such information as the Plan Administrator
                 requests in its evaluation of the Participant's request;

            2.   The amount distributed, if any, shall in no event exceed the
                 balance of the Participant's Employee Deferral Contributions
                 Account (excluding earnings credited thereto after December 31,
                 1988) and Rollover Account; and

            3.   A Participant's request for a hardship distribution shall not
                 be honored to the extent it requires the distribution of an
                 amount serving as security for a loan to the Participant

12.6   Direct Rollover Distributions

       Notwithstanding any provision of the Plan to the contrary that would
       otherwise limit a distributee's election under this Section, a
       distributee may elect, at the time and in the manner prescribed by the
       Plan Administrator, to have any portion of an eligible rollover
       distribution paid directly to an eligible retirement plan specified by
       the distributee in a direct rollover.

       A.   Eligible Rollover Distribution

            An eligible rollover distribution is any distribution of all or any
            portion of the balance to the credit of the distributee, except that
            an eligible rollover distribution does not include: any distribution
            that is one of a series of substantially equal periodic payments
            (not less frequently than annually) made for the life (or life
            expectancy) of the distributee or the joint lives (or joint life
            expectancies) of the distributee and the distributee's designated
            beneficiary, or for a specified period of ten years or more; any
            distribution to the extent such a distribution is required under
            Code Section 401(a)(9); the portion of any distribution that is not
            includible in gross income (determined without regard to the
            exclusion for net unrealized appreciation with respect to employer
            securities); and any portion of a hardship withdrawal pursuant to
            Section 12.5 made

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<PAGE>

            from a Participant's Employee Deferral Account after December 31,
            1998.

       B.   Eligible Retirement Plan

            An eligible retirement plan is an individual retirement account
            described in Code Section 408(a), an individual retirement annuity
            described in Code Section 408(b), an annuity plan described in Code
            Section 403(a), or a qualified trust described in Code Section
            401(a), that accepts the distributee's eligible rollover
            distribution. However, in the case of an eligible rollover
            distribution to the surviving spouse, an eligible retirement plan is
            an individual retirement account or individual retirement annuity.

       C.   Distributee

            A distributee includes an employee or former employee. In addition,
            the employee's or former employee's surviving spouse and the
            employee's or former employee's spouse or former spouse who is the
            alternate payee under a qualified domestic relations order, as
            defined in Code Section 414(p), are distributees with regard to the
            interest of the spouse or former spouse.

       D.   Direct Rollover

            A direct rollover is a payment by the Plan to the eligible
            retirement plan specified by the distributee.

12.7   Waiver of 30-Day Election Period

       If a distribution is one to which Code Sections 401(a)(11) and 417 do not
       apply, such distribution may commence less than 30 days after the notice
       required by Income Tax Regulation (S) Section 1.411(a)-11(c) is given
       provided (i) the Committee clearly informs the Participant that the
       Participant has a right to a period of at least 30 days after receiving
       the notice to consider the decision of whether or not to elect a
       distribution or a direct rollover, and (ii) the Participant, after
       receiving the notice, affirmatively elects a distribution or a direct
       rollover.

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<PAGE>

                           XIII. TOP HEAVY PROVISIONS

13.1  Applicability

      Notwithstanding any other provision of the Plan to the contrary, the
      provisions of this Article shall apply for any Plan Year, beginning after
      December 31, 1983, in which the Plan is a Top-Heavy Plan as defined in
      Code Section 416(g).

13.2  Definitions

      A.   Aggregation Group

           Aggregation Group includes each plan maintained by the Employer or an
           Affiliate in which a Key Employee participates and each other plan
           maintained by the Employer or an Affiliate which enables any plan in
           which a Key Employee participates to meet the requirements of Code
           Section 401(a)(4) or 410. In addition, the Employer may elect to
           include other plans in the Aggregation Group which satisfy the
           requirements of Code Sections 401(a)(4) and 410 when considered
           together with the plans that are required to be aggregated. Any plan,
           however, that is or may be permissively included in the Aggregation
           Group upon an election by the Employer shall not be subject to the
           provisions of this Article.

      B.   Determination Date

           Determination Date shall be the last day of the preceding Plan Year
           or, if such Plan Year is the first Plan Year of the Plan, the last
           day of such Plan Year. In the case of plans included in an
           Aggregation Group, the present value of accrued benefits or accounts
           shall be combined for all aggregated plans that have a Determination
           Date that falls in the same calendar year.

      C.   Key Employee

           Key Employee means an Employee or a former Employee (or the
           beneficiary of such an Employee) who during the Plan Year ending on
           the Determination Date or during the four (4) preceding Plan Years
           is, as determined under Code Section 416(i):

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<PAGE>

      1.   An officer of the Employer having an annual compensation greater than
           50 percent of the amount in effect under Code Section 415(b)(1)(A);

      2.   One of the ten Employees having annual compensation from the Employer
           greater than the amount in effect under Code Section 415(c)(1)(A) and
           owning (or considered as owning within the meaning of Code Section
           318) the largest interest in the Employer;

      3.   A five (5) percent owner; or

      4.   A one (1) percent owner who has annual compensation from the Employer
           in excess of $150,000.

      Code Section 416(i) is hereby incorporated in the Plan by reference for
      the purpose of determining whether an Employee is a Key Employee, a former
      Key Employee, or a Non-Key Employee.

D.    Non-Key Employee

      Non-Key Employee means an Employee or a former Employee (or the
      beneficiary of such an Employee) who during the Plan Year ending on the
      Determination Date or during the four (4) preceding Plan Years is not a
      Key Employee or former Key Employee as defined under Code Section 416(i).

E.    Super Top-Heavy

      A plan or plans required to be included in the Aggregation Group shall be
      Super Top-Heavy for a Plan Year if on the Determination Date for such Plan
      Year the Top-Heavy Ratio exceeds ninety percent (90%).

F.    Top-Heavy

      A plan or plans required to be included in the Aggregation Group shall be
      Top-Heavy for a Plan Year if on the Determination Date for such Plan Year
      the Top-Heavy Ratio exceeds sixty percent (60%).

G.    Top-Heavy Ratio

      Top-Heavy Ratio means the ratio determined from dividing the present value
      of accrued benefits and accounts for Key Employees by the total

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<PAGE>

           value of accrued benefits and accounts for Key Employees and Non-Key
           Employees. The value of accrued benefits and accounts shall be
           determined as prescribed under paragraph H below.

     H.    Valuation of Accrued Benefit

           1.   Defined Contribution Plan

                The present value of an accrued benefit under a defined
                contribution plan is the account balance derived from Employer
                and nondeductible Employee contributions as of the most recent
                valuation date within the twelve (12) month period ending on the
                Determination Date, plus any contributions actually made since
                such date or, in the case of a plan subject to minimum funding
                requirements, contributions required to be made as of the
                Determination Date. All defined contribution plans required to
                be included or permissively included in the Aggregation Group
                shall be treated as a single plan.

           2.   Defined Benefit Plan

                The present value of an accrued benefit under a defined benefit
                plan is the value of the monthly retirement benefit derived from
                Employer or nondeductible Employee contributions, determined as
                of the most recent valuation date within the twelve (12) month
                period ending on the Determination Date, and determined as
                though the individual terminated service as of such valuation
                date. The benefit of Employee, other than a Key Employee, shall
                be treated as accruing under the method that is used for accrual
                purposes for all plans of the Employer and its Affiliates or, if
                there is no such method, as if such benefit accrued not more
                rapidly than the slowest accrual rate permitted under Code
                Section 411(b)(1)(C). Reasonable actuarial assumptions shall be
                used to determine the value of the benefit under the plan;
                provided, that assumptions as to future withdrawal or future
                salary increases shall not be used. All defined benefit plans
                required to be included or permissively included in the
                Aggregation Group shall be treated as a single plan and the same
                actuarial assumptions shall be used to value benefits under each
                of the plans included in the Aggregation Group.

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           3.   Distributions Included

                In determining the present value of any accrued benefits and the
                amount of any account to be used to determine the Top-Heavy
                Ratio, distributions within the period of five (5) consecutive
                Plan Years ending on the Determination Date, and such rollover
                accounts as prescribed by regulation by the Secretary of the
                Treasury, shall be added to the value of accrued benefits as of
                such Determination Date. The accrued benefits of a former Key
                Employee and the accrued benefits of an individual who has not
                performed any services for the Employer maintaining the Plan at
                any time during the five (5) year period ending on the
                Determination Date shall, however, be disregarded.

13.3  Minimum Contributions

      For any Plan Year in which the Plan's Aggregation Group is Top-Heavy, the
      Employer contribution and forfeitures allocated to a Participant who is a
      Non-Key Employee in the employ of the Employer on the last day of the Plan
      Year shall be not less than the lesser of:

           A.   Three percent (3%) of the Participant's Compensation; or

           B.   The percentage at which contributions are made under the Plan
                for the Key Employee for whom such percentage is the highest for
                the Plan Year. In determining the contribution rate for a Key
                Employee, Employee elective contributions under a plan qualified
                under Code Section 401(k) shall be included.

                If the Plan is required to be included in an Aggregation Group
                and the Plan allows a defined benefit plan required to be in
                such Group to meet the requirements of Code Section 401(a)(4) or
                410, the minimum contribution, in such circumstances, shall be
                not less than three (3) percent of the Participant's
                Compensation for the Plan Year. All defined contribution plans
                required to be included in the Aggregation Group shall be
                treated as a single plan.

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<PAGE>

13.5  Benefits Under Different Plans

      If the Employer maintains one or more defined contribution plans (which
      shall be treated as a single defined contribution plan for purposes of
      this Article) in addition to a defined benefit plan and a Non-Key Employee
      participates in both types of plans, the Employer shall provide such
      Participant with the minimum benefit required under the defined benefit
      pension plan, offset, however, by any benefit provided under the
      Employer's defined contribution plan.

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<PAGE>

                       XIV. PROVISION AGAINST ANTICIPATION

Until distribution pursuant to the terms hereof, no Participant shall have the
right or power to alienate, anticipate, commute, pledge, encumber or assign any
of the benefits, proceeds or avails set aside for him under the terms of the
Plan, and no such benefits, proceeds or avails shall be subject to seizure by
any creditor of the Participant or the Employer under any writ or proceedings at
law or in equity, provided, that the terms of this Section shall not prohibit
the creation, assignment or recognition of a right to any benefit payable with
respect to a Participant if such creation, assignment or recognition of a right
is made under a qualified domestic relations order as defined under Code Section
414(p), a judgment, order, decree or settlement agreement described in Code
Section 401(a)(13) issued or entered into after August 4, 1997, or as security
for a loan from the Plan which is permitted pursuant to Code Section 4975.

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XV.    ADMINISTRATIVE COMMITTEE - NAMED FIDUCIARY AND ADMINISTRATOR

15.1   Appointment of Committee

       The Employer shall appoint an Administrative Committee comprised of one
       or more persons (herein referred to as the Committee) to serve for such
       terms as the Employer may designate or until a successor has been
       appointed or until removal by the Employer. The Employer shall advise the
       Trustee in writing of the names of the members of the Committee and any
       changes thereafter made in the membership of the Committee. Vacancies due
       to resignation, death, removal or other causes shall be filled by the
       Employer. Members shall be bonded except as may otherwise be allowed by
       law. A member of the Committee may be paid reasonable compensation for
       the member's service, provided, that a member who is a full-time employee
       of the Employer shall serve without compensation. All reasonable expenses
       of the Committee shall be paid by the Employer. The number of the
       Committee may be changed by the Employer at any time.

15.2   Committee Action

       The Committee shall appoint a secretary who shall keep minutes of the
       Committee's proceedings and all data, records and documents pertaining to
       the Committee's administration of the Plan. The Committee shall act by
       majority vote of its members in office at that time, such vote to be
       taken at a meeting or, in writing, without a meeting. The Committee may,
       by such majority action, authorize its secretary or any one or more of
       its members to execute any document or documents on behalf of the
       Committee, in which event the Committee shall notify the Trustee in
       writing of such action and the name or names of those so designated. The
       Trustee shall accept and rely conclusively upon any direction or document
       executed by such secretary, member or members as representing action by
       the Committee until the Committee shall file with the Trustee a written
       revocation of such designation. A member of the Committee who is also a
       Participant hereunder shall not vote or act upon any matter relating
       solely to such member.

15.3   Rights and Duties

       The Committee shall be the Plan Administrator and Named Fiduciary of the
       Plan within the meaning of ERISA. The Committee, on behalf of the
       Participants and their Beneficiaries, shall have the authority to control
       and

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<PAGE>

       manage the operation and administration of the Plan and shall have all
       powers and discretionary authority necessary to accomplish those
       purposes. It will interpret and apply all Plan provisions and may correct
       any defect, supply any omission or reconcile any inconsistency or
       ambiguity in such manner as it deems advisable. It will make all final
       determinations concerning eligibility, benefits and rights hereunder, and
       all other matters concerning plan administration and interpretation. All
       determinations and actions of the Committee will be conclusive and
       binding upon all persons, except as otherwise provided herein or by law,
       and except that the Committee may revoke or modify a determination or
       action previously made in error. Any action or omission by the Committee
       will be subject to review (by a court or otherwise) only for an abuse of
       discretion. The Committee will exercise all powers and authority given to
       it in a nondiscriminatory manner, and will apply uniform administrative
       rules of general application in order to assure similar treatment of
       persons in similar circumstances. The responsibility and authority of the
       Committee shall include, but shall not be limited to, the following:

       A.   Construing and interpreting the terms and provisions of the Plan;

       B.   Determining the eligibility of any person for benefits under the
            Plan, the amount of any such benefits and all other questions
            pertaining to the rights of Participants, their Spouses and their
            Beneficiaries hereunder;

       C.   Authorizing all disbursements by the Trustee from the Trust;

       D.   Maintaining all necessary records for the administration of the Plan
            other than those that the Trustee has specifically agreed to
            maintain;

       E.   Interpreting the provisions of the Plan and publishing such rules
            for the regulation of the Plan as are deemed necessary and not
            inconsistent with the terms of the Plan;

       F.   Establishing reasonable procedures to determine the qualified status
            of domestic relations orders and to administer distributions under
            such qualified orders;

       G.   Notifying the Participant and any other alternate payee, as defined
            under Code Section 414(p)(8), of the receipt of a domestic relations
            order, the Plan's procedures for determining the qualified status of
            such an order, and the determination made in connection with such
            order;

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<PAGE>

       H.   Directing the Trustee to make distributions from the Trust Fund to
            Participants, former Participants, and beneficiaries of the Trust in
            accordance with the provisions of the Plan. The Trustee shall
            withhold from such distributions any amount required to be withheld
            pursuant to Code Section 3405 unless the recipient of such
            distributions has made an appropriate election under Code Section
            3405(a)(2) or 3405(b)(3).

15.4   Investments

       The Committee may appoint, in writing, an Investment Manager or Managers
       to manage and control all or part of the investments of the Plan. No
       appointment of an Investment Manager shall be effective until the
       Investment Manager has acknowledged in writing that the Investment
       Manager is a fiduciary of the Plan, and that the Investment Manager has
       complied with the bonding requirements of ERISA.

15.5   Information, Reporting and Disclosure

       To enable the Committee to perform its functions, the Employer shall
       supply full and timely information to the Committee on all matters
       relating to the Compensation of all Participants; their continuous,
       regular employment; their retirement, death or cause for termination of
       employment; and such other pertinent facts as the Committee may require,
       and the Committee shall furnish the Trustee such information as may be
       pertinent to the Trustee's administration of the Trust. The Committee, as
       Plan Administrator, shall have the responsibility of complying with the
       reporting and disclosure requirements of ERISA and, to the extent
       applicable, any other federal or state law.

15.6   Independent Qualified Accountant

       Unless the Plan is exempt from the requirement by applicable law or
       regulation, the Committee shall engage, on behalf of all Participants, an
       independent qualified public accountant who shall conduct such
       examinations of the financial statements of the Plan and of other books
       and records of the Plan as the accountant may deem necessary to enable
       the accountant to form an opinion as to whether the financial statements
       and schedules required by law to be included in any reports are presented
       fairly and in conformity with generally accepted accounting principles
       applied on a basis consistent with that of any preceding year.

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<PAGE>

15.7   Standard of Care Imposed Upon the Committee

       The Committee shall discharge its duties with respect to the Plan solely
       in the interest of the Participants and Beneficiaries; and

       A.   For the exclusive purpose of providing benefits to Participants and
            their Beneficiaries and defraying reasonable expenses of the Plan;

       B.   With the care, skill, prudence and diligence under the circumstances
            then prevailing that a prudent person, acting in a like capacity and
            familiar with such matters, would use in the conduct of an
            enterprise of like character and with like aims; and

       C.   In accordance with the Plan provisions insofar as such provisions
            are consistent with the provisions of ERISA.

15.8   Allocation and Delegation of Responsibility

       The Committee may, by written rule promulgated under Section 15.3 above,
       allocate fiduciary responsibilities among Committee members and may
       delegate to persons other than Committee members the authority to carry
       out fiduciary responsibilities under the Plan, provided that no such
       responsibility shall be allocated or delegated to the Trustee without its
       written consent. As used in this part, the term "fiduciary
       responsibility" shall not include any responsibility provided in the
       Trust Agreement to manage or control the assets of the Plan.

       The Committee, in making the above allocation of fiduciary
       responsibilities, may provide that a person or group of persons may
       serve, with respect to the Plan, in more than one fiduciary capacity. The
       Committee or, so long as the Committee shall have made written approval,
       persons to whom fiduciary responsibilities have been delegated by the
       Committee may employ one or more persons to render advice with regard to
       any responsibility such fiduciary has under the Plan.

       In the event a fiduciary responsibility is allocated to a Committee
       member, no other Committee member shall be liable for any such act or
       omission of the person to whom the responsibility is allocated except as
       may be otherwise required by law. If a fiduciary responsibility is
       delegated to a person other than a Committee member, the Committee shall
       not be responsible or liable for an

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<PAGE>

       act or omission of such person in carrying out such responsibility except
       as may otherwise be required by law.

15.9   Bonding

       Each fiduciary of the Plan and every person handling Plan funds shall be
       bonded unless exempt from such requirement by law. It shall be the
       obligation of the Committee to assure compliance with applicable bonding
       requirements. The Trustee shall not be responsible for assuring that
       bonding requirements are complied with and such responsibility is
       specifically allocated to the Committee.

15.10  Claims Procedure

       A.    Effective Date

             The claims procedure set forth below applies to claims decided on
             or after January 1, 2002. Claims decided prior to January 1, 2002,
             shall be decided under the claims procedure in effect at the time
             of such decision.

       B.    Filing Claim

             A Participant or a Beneficiary, or the authorized representative of
             either (the "Claimant"), who believes that he is then entitled to
             benefits hereunder may file a written claim for such benefits with
             the Secretary of the Administrative Committee. The Administrative
             Committee may prescribe a form for filing such claims, and, if it
             does so, a claim will not be deemed properly filed unless such form
             is used, but the Secretary of the Administrative Committee shall
             provide a copy of such form to any person whose claim for benefits
             is improper solely for this reason.

       C.    Claim Review

             Claims that are properly filed will be reviewed by the
             Administrative Committee, which will make its decision with respect
             to such claim and notify the Claimant in writing of such decision
             within 90 days (45 days in the case of a claim related to permanent
             disability (within the meaning of Section 11.2)) after the
             Secretary of the Administrative Committee's receipt of the written
             claim; provided that the 90-day period (45-day period in the case
             of a claim related to permanent disability (within the meaning of
             Section 11.2)) can be extended for up

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<PAGE>

             to an additional 90 days (30 days in the case of a claim related to
             permanent disability (within the meaning of Section 11.2)) if the
             Administrative Committee determines that special circumstances
             require an extension of time to process the claim and the Claimant
             is notified of the extension, the reasons therefor, and the date by
             which the Administrative Committee expects to render a decision
             prior to the commencement of the extension. If the claim is wholly
             or partially denied, the written response to the Claimant shall
             include:

             1.   the specific reason or reasons for the adverse determination;

             2.   references to the specific provisions of the Plan document on
                  which the determination is based;

             3.   a description of any additional information necessary for the
                  Claimant to perfect his claim and an explanation why such
                  information is necessary;

             4.   a description of the Plan's review procedures (and the time
                  limits applicable thereto), as set forth in subsection (D)
                  immediately below;

             5.   a statement of the Claimant's right to bring a civil action
                  under ERISA Section 502(a) following an adverse benefit
                  determination on appeal; and

             6.   in the case of an adverse benefit determination related to
                  permanent disability (within the meaning of Section 11.2):

                  a.   if an internal rule, guideline, protocol or other similar
                       criterion was relied upon in making the adverse
                       determination, either the specific rule, guideline,
                       protocol or other similar criterion; or a statement that
                       such a rule, guideline, protocol or similar criterion was
                       relied upon in making the adverse determination and that
                       a copy of such rule, guideline, protocol or other
                       criterion will be provided free of charge to the Claimant
                       upon request; or

                  b.   if the adverse benefit determination is based on a
                       medical necessity or experimental treatment or similar
                       exclusion or limit, either an explanation of the
                       scientific or clinical judgment for the determination,
                       applying the terms of the

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<PAGE>

                       Plan to the Claimant's medical circumstances, or a
                       statement that such explanation will be provided free of
                       charge upon request.

       D.    Appeal

             If the claim is denied in whole or in part, the Claimant may appeal
             such denial by filing a written request for appeal with the
             Secretary of the Administrative Committee within 60 days (180 days
             in the case of a claim related to permanent disability (within the
             meaning of Section 11.2)) of receiving written notice that the
             claim has been denied. Such written request for appeal should
             include:

             1.   a statement of the grounds on which the appeal is based;

             2.   reference to the specific provisions in the Plan document
                  which support the claim;

             3.   the reason or argument why the Claimant believes the claim
                  should be granted and evidence supporting each reason or
                  argument; and

             4.   any other relevant documents or comments that the Claimant
                  wishes to include.

             Appeals will be considered by the Administrative Committee, which
             will take into account all comments, documents, records and other
             information submitted by the Claimant relating to the claim,
             without regard to whether such information was submitted or
             considered in the initial determination. The Administrative
             Committee will make its decision with respect to any appeal, and
             notify the Claimant in writing of such decision, within 60 days (45
             days in the case of a claim related to permanent disability (within
             the meaning of Section 11.2)) after the Administrative Committee's
             receipt of the written request for appeal; provided that the 60-day
             period (45-day period in the case of a claim related to permanent
             disability (within the meaning of Section 11.2)) can be extended
             for up to an additional 60 days (45 days in the case of a claim
             related to permanent disability (within the meaning of Section
             11.2)) if the Administrative Committee determines that special
             circumstances require an extension of time to process the appeal
             and the Claimant is notified of the extension, and the reasons
             therefor, prior to

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page XV-7

<PAGE>

             the commencement of the extension.  In the event the claim is
             denied on appeal, the written denial will include:

             1.   the specific reason or reasons for the adverse determination;

             2.   references to the specific provisions of the Plan document on
                  which the benefit determination is based;

             3.   a statement that the Claimant is entitled to receive, upon
                  request and free of charge, reasonable access to, and copies
                  of, documents, records, and other information relevant to the
                  Claimant's claim for benefits;

             4.   a statement of the Claimant's right to bring a civil action
                  under ERISA Section 502(a);

             5.   in the case of an adverse benefit determination related to
                  permanent disability (within the meaning of Section 11.2):

                  a.   if an internal rule, guideline, protocol or other similar
                       criterion was relied upon in making the adverse
                       determination, either the specific rule, guideline,
                       protocol or other similar criterion; or a statement that
                       such a rule, guideline, protocol or similar criterion was
                       relied upon in making the adverse determination and that
                       a copy of such rule, guideline, protocol or other
                       criterion will be provided free of charge to the Claimant
                       upon request;

                  b.   if the adverse benefit determination is based on a
                       medical necessity or experimental treatment or similar
                       exclusion or limit, either an explanation of the
                       scientific or clinical judgment for the determination,
                       applying the terms of the Plan to the Claimant's medical
                       circumstances, or a statement that such explanation will
                       be provided free of charge upon request; and

                  c.   the following statement: "You and your Plan may have
                       other voluntary alternative dispute resolution options,
                       such as mediation. One way to find out what may be
                       available is to contact your local U.S. Department of
                       Labor Office or your State insurance regulatory agency."

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<PAGE>

       E.    Provision of Documents, Records and Other Information

             During the appeal period, the Claimant will be provided, upon
             request and free of charge, reasonable access to, and copies of,
             documents, records and other information relevant to his claim. A
             document, record or other information will be considered "relevant"
             to a Claimant's claim, if such document, record or other
             information:

             (1)  Was relied upon by the Administrative Committee in reaching
                  its decision on the claim;

             (2)  Was submitted, considered or generated in the course of
                  deciding the claim, without regard to whether the document,
                  record or other information was relied upon by the
                  Administrative Committee in reaching its decision on the
                  claim; or

             (3)  Demonstrates compliance with the administrative processes and
                  safeguards required under Department of Labor regulations in
                  making the benefit determination.

       F.    Standard of Review

             Any further review, judicial or otherwise, of the Administrative
             Committee's decision on the Claimant's claim will be limited to
             whether, in the particular instance, the Administrative Committee
             abused its discretion. In no event will such further review,
             judicial or otherwise, be on a de novo basis, as the Administrative
             Committee has discretionary authority to determine eligibility for
             benefits and to construe and interpret the terms of the Plan.

15.11  Unclaimed Account Procedures

       If a Participant or the Participant's Surviving Spouse or Beneficiary,
       if applicable, does not claim the Participant's vested Accrued Benefit,
       the Participant's vested Accrued Benefit shall be forfeited and applied
       in accordance with the provisions of Section 4.1B.3 or 5.2, as
       applicable. An unclaimed vested Accrued Benefit shall be forfeited on the
       later of the date that is 6 months after the date the Plan Administrator
       notifies the Participant, Surviving Spouse or Beneficiary, as applicable,
       by certified or registered mail addressed to his last known address, that
       he is entitled to a benefit or the date on which occurs the earlier of
       the Participant's attainment of Normal

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<PAGE>

        Retirement Age or death, provided that the Participant, Surviving Spouse
        or Beneficiary has not made his whereabouts known prior to such date.

        If a Participant's vested Accrued Benefit is forfeited pursuant to this
        Section 15.11 and the Participant, Surviving Spouse or Beneficiary, as
        applicable, subsequently makes a claim for benefits, the forfeited
        Accrued Benefit shall be restored to the same dollar amount as was
        forfeited, unadjusted for any gains or losses occurring after the date
        on which it was forfeited. Such restoration shall be made first from the
        amount, if any, of Participant forfeitures occurring during the year of
        reinstatement. If such forfeitures are insufficient, restoration will be
        made from a special Employer contribution earmarked for that purpose.
        The reinstated vested Accrued Benefit shall be distribute to the
        Participant, Surviving Spouse or Beneficiary in accordance with the
        preceding provisions of the Plan.

15.12   Funding Policy

        The Committee shall be responsible for establishing and carrying out a
        funding policy for the Plan. In establishing such a policy, the
        short-term liquidity needs of the Plan shall be determined, to the
        extent possible, by considering, among other factors, the anticipated
        retirement date of Participants, turnover and contributions to be made
        by the Employer. In addition, all or a portion of the Plan's assets can
        be invested in "qualifying employer securities," within the meaning of
        Section 407(d)(5) of ERISA, including, but not limited to, common stock
        of Immunex Corporation. The funding policy and method so established
        shall be considered by the Committee in selecting Investment Funds
        pursuant to Section 6.1 and communicated by the Committee to any other
        fiduciary responsible for investment, including the Trustee and any
        Investment Manager, as applicable.

15.13   Indemnification

        The Employer does hereby indemnify and hold harmless each Committee
        member from any loss, claim or suit arising out of the performance of
        obligations imposed hereunder and not arising from said Committee
        member's willful neglect, misconduct or gross negligence.

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<PAGE>

                     XVI. APPOINTMENT OF INVESTMENT MANAGER

16.1    Authority for Appointment

        The Plan Administrator shall have the authority prescribed in ERISA
        Section 402(c)(3) to appoint one or more Investment Managers and
        contract with each for management of any part of the Fund. Selection and
        retention of an Investment Manager shall be in the Plan Administrator's
        discretion. Each Investment Manager shall have the power to manage,
        acquire and dispose of that part of the Fund designated by the Plan
        Administrator. The Investment Manager has no responsibility for Plan
        operation or administration.

16.2    Investment Manager Discretion

        Without limitation of the foregoing and if an Investment Manager is
        appointed:

        A.   The Trustee, on Plan Administrator direction, shall segregate the
             Fund or any part thereof into one or more Investment Manager
             accounts. The Plan Administrator shall appoint an Investment
             Manager for each account and designate to the Trustee the part of
             the Fund to be managed by each Investment Manager. The Trustee
             shall send directly to the Investment Manager the proxies under the
             direction of the Investment Manager, who shall then vote such
             proxies at their discretion.

        B.   Upon request, the Plan Administrator shall advise others that the
             Investment Manager is authorized to enter orders for such
             Investment Manager's account, but the Trustee shall always have
             custody of account assets. The Trustee shall give the Investment
             Manager copies of, or extracts from, such portions of its records
             relating to such accounts as are necessary for the exercise of such
             Investment Manager's functions.

        C.   The Trustee shall neither question nor inquire about any action,
             direction or failure to give directions of any Investment Manager
             and shall not review the securities held in any Investment Manager
             account nor make any suggestions to the Investment Manager with
             respect to investment of, or disposition of, investments in any
             Investment Manager account. The Trustee shall not be liable for any
             act or omission of an Investment Manager or be under any obligation
             to invest or otherwise manage any asset of the Fund that is subject
             to the management of an Investment Manager. The Trustee shall not
             be liable for loss due to action or

Immunex Corporation Profit Sharing 401(k) Plan and Trust              Page XVI-1

<PAGE>

             inaction complying with or in the absence of the Investment
             Manager's directions.

        D.   The Plan Administrator, by notice to the Trustee and the Investment
             Manager, may terminate at any time the authority of an Investment
             Manager to manage the account. In such event or upon resignation of
             an Investment Manager, the Plan Administrator shall either appoint
             a successor Investment Manager for the account or, with the
             Trustee's consent, direct the Trustee to assume responsibility for
             the investment management of the assets in the account, in which
             case such assets shall no longer be segregated from the other
             assets of the Fund. Until receipt of notice of such termination or
             resignation, the Trustee shall rely on the latest prior notice of
             the appointment of an Investment Manager.

        E.   Each Investment Manager to whom any fiduciary responsibility with
             respect to the Plan or Trust Fund is delegated shall discharge such
             responsibility in accordance with the standards set forth in ERISA
             Section 404(a).

        F.   Upon written direction of an Investment Manager received by the
             Trustee, the Trustee is authorized to purchase or sell stock,
             bonds, commercial paper, mortgages, or other securities or
             indebtedness of the Trustee or any of its affiliates.

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<PAGE>

                   XVII. INVESTMENT OF TRUST FUNDS BY TRUSTEE

The Trustee shall exercise authority or discretion in the management and control
of the assets of the Plan, except to the extent the selection of Investment
Funds for investment by Participants is made by the Committee and except to the
extent the management of any part of the Trust Fund has been delegated to any
Investment Manager pursuant to Article XVI. Without limiting the generality of
the foregoing, the Trustee shall invest and reinvest the principal and income of
the Trust Fund in common Investment Funds, real estate, real estate contracts,
government, municipal or corporation bonds, debentures or notes, including notes
secured by deeds of trust, common and preferred stocks, or other forms of
property whether real, personal or mixed, including investments for which
interest is guaranteed by a bank, insurance company or other financial
institution. In the event the Trustee invests any assets of the Plan in a common
Investment Fund maintained by the Trustee or any bank affiliated with the
Trustee (within the meaning of Section 1504 of the Code), the terms of such
common fund are hereby adopted as part of the Plan and such terms are, by this
reference, incorporated as part of this Document.

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<PAGE>

                       XVIII. POWERS AND DUTIES OF TRUSTEE

18.1    Powers of Trustee

        The Trustee shall have the following powers with regard to Trust assets.
        If investment discretion is exercised by a fiduciary or fiduciaries
        other than the Trustee, to the extent any of the following powers
        involve the exercise of investment discretion, the Trustee shall
        exercise such power at the direction of the investment fiduciary or
        fiduciaries.

        A.   To sell, convey, transfer, mortgage, pledge, lease or otherwise
             dispose of Trust assets without the approval of any court and
             without obligation upon any person dealing with the Trustee to see
             to the application of any money or other property delivered to it;

        B.   To exchange property or securities for other property or
             securities;

        C.   To keep any or all securities or other property in the name of a
             nominee, to deposit securities in a securities depository and hold
             them in the name of its nominee, and to hold securities in book
             entry form at a Federal Reserve Bank;

        D.   To vote, either in person or by proxy, any shares of stock or other
             securities held as part of the assets of the Trust, provided the
             Trustee shall forward proxies to the appropriate investment
             fiduciary, if the Trustee does not exercise investment discretion
             with respect to the security to be voted;

        E.   To collect, as the same shall become due and payable, the principal
             or income of the Trust and, if necessary, to take such legal
             proceedings as may deem advisable in the best interest of the Trust
             to collect any sum of money due the Trust. The Trustee shall be
             under no obligation to commence suit unless it shall have been
             first indemnified by the Trust Fund or the Employer with respect to
             expenses or losses to which it may be subjected through taking such
             action;

        F.   To borrow money for purposes of the Trust and to have power to
             execute and deliver notes, mortgages, pledges or other instruments
             as may be necessary in connection therewith;

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<PAGE>

      G.   To pay the expenses of the Trust out of the Fund, including any taxes
           and reasonable compensation for its services as Trustee, if and to
           the extent that the Employer does not pay such expenses and
           compensation;

      H.   To receive and hold in safekeeping the assets of the Trust, provided
           assets invested in a registered mutual fund or in any similar pooled
           fund for which the Trustee is not the custodian shall be held in
           safekeeping by the custodian of such fund, and the Trustee shall not
           be responsible for their safekeeping;

      I.   To employ agents and to utilize the services of affiliates in
           performing its duties hereunder;

      J.   To deposit Trust funds in an interest-bearing account with a bank or
           similar financial institution, including the Trustee, provided such
           deposits shall bear a reasonable rate of interest;

      K.   To determine the fair market value of the Trust assets on an annual
           and other periodic basis. The Trustee shall perform such valuation in
           a reasonable and consistent manner in accordance with generally
           accepted accounting principles. The Trustee may utilize and shall be
           entitled to rely upon published quotation and pricing services that
           it considers reliable. In the event that the Committee or an
           Investment Manager directs investment into assets for which no
           published pricing information is available, the Trustee may obtain
           their fair market value from the Committee, the Investment Manager,
           or an appraiser selected by them, and shall be entitled to rely
           completely upon the value provided. If the Committee or Investment
           Manager is unable to unwilling to provide such valuation, the Trustee
           may engage an appraiser or other expert to determine the fair market
           value, and the fee for such service shall be an administrative
           expense of the Trust; and

      L.   Upon direction of the Committee or an Investment Manager,
           acquire and maintain deposit administration contracts,
           insurance company investment contracts, individual annuities,
           or group annuity policies ("Contracts"). The Trustee shall
           execute the application for a Contract and a Contract in such
           form as the investment fiduciary and the Trustee shall agree.
           The Trustee shall be the legal owner of all Contracts held in
           the Trust. Upon the direction of the investment fiduciary, the
           Trustee shall pay from the Trust the premiums, assessments,
           charges, or other costs to acquire and maintain Contracts. The
           Trustee shall have no duty

Immunex Corporation Profit Sharing 401(k) Plan and Trust            Page XVIII-2

<PAGE>

           to make such payment unless the Trustee receives such direction. If
           the cash available in the Trust is not sufficient to pay all the sums
           the investment fiduciary has directed the Trustee to pay, the Trustee
           shall promptly notify the investment fiduciary of the deficiency, and
           the Trustee shall have no duty to make any such payment until it
           receives sufficient cash to make the payment. Upon direction of the
           investment fiduciary, the Trustee shall collect and receive dividends
           or other income of the Contract or leave the income with the issuing
           company; convert from one form of Contract to another; designate a
           mode of settlement of the proceeds of a Contract; sell or assign a
           Contract; surrender a Contract for cash; agree with the issuing
           company to any release, modification, reduction, or amendment
           thereof; and without limitation exercise any other right, option, or
           privilege that belongs to the legal owner of a Contract. The Trustee
           shall have no discretion with respect to the exercise of any of the
           foregoing powers or any other action permitted by a Contract held in
           the Trust, but it shall exercise such powers or take such action only
           upon the direction of the investment fiduciary.

      M.   Generally, with relation to the assets of the Trust, to do all such
           acts, execute all such instruments, take all such proceedings and
           exercise all such rights and privileges as it deems necessary to
           carry out its obligations hereunder to the extent consistent with the
           rights of Participants and Beneficiaries and the standard of care
           imposed by Section 18.4;

18.2  Annual Accounts

      The Trustee, within a reasonable period following the close of each Plan
      Year (not to exceed 120 days), shall render to the Plan Administrator a
      certified account of its administration of the Trust during the preceding
      year, which shall include such information maintained by the Trustee
      necessary to enable the Plan Administrator to comply with the reporting
      requirements of federal law. The Plan Administrator shall promptly review
      the Trustee's accountings and shall file any exceptions within 120 days of
      receipt. In the event it files no exception within such 120-day period,
      the accounting shall be deemed settled for the period covered by it.

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18.3  Notices and Directions

      Whenever a notice or direction is given to the Trustee, the instrument
      shall be signed by a person or persons duly authorized by resolution,
      minutes, or similar action to act on behalf of the Employer, the Plan
      Administrator, an Investment Manager, or any other person or agent with
      authority to direct the Trustee ("Authorized Person"). The Trustee shall
      be protected in acting upon any such notice, resolution, order,
      certificate, opinion, telegram, letter or other document believed to be
      genuine and to have been signed by the proper party or parties, and may
      act thereon without notice to any Participant and without considering the
      rights of any Participant.

      An Authorized Person may give, and the Trustee may rely upon, facsimile
      instructions. An Authorized Person is responsible to verify that facsimile
      instructions delivered to the Trustee are legible in form, clear in
      content, and properly executed. The Trustee shall not be liable for the
      security measures followed by an Authorized Person with respect to
      transmission of facsimile instructions. Should any person request
      disbursement by wire, the Trustee may require as a condition to such
      disbursement that such person conform to Trustee's standard policies and
      procedures for funds transfer and execute Trustee's standard funds
      transfer agreement.

      The Trustee shall not be required to determine or make any investigation
      to determine' the identity or mailing address of any person entitled to
      benefits under the Plan and shall send checks and other papers to such
      persons at addresses as may be furnished it by the Plan Administrator.

18.4  Standard of Care Imposed Upon Trustee

      The Trustee shall discharge its responsibilities under the Plan and Trust
      solely in the interests of the Participants and Beneficiaries; and

      A.   For the exclusive purpose of providing benefits to Participants and
           their Beneficiaries and defraying reasonable expenses of
           administering the Plan;

      B.   With care, skill, prudence and diligence under the circumstances then
           prevailing that a prudent person, acting in a like capacity and
           familiar with such matters, would use in the conduct of an enterprise
           of a like character and with like aims;

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<PAGE>

      C.   To the extent it exercises investment discretion, by diversifying the
           investments of the Plan so as to minimize the risk of large losses,
           unless under the circumstances it is clearly prudent not to do so;
           and

      D.   In accordance with the terms of this Plan and Trust Agreement insofar
           as such provisions are consistent with the provisions of ERISA.

18.5  Trustee's Acknowledgment of Responsibility

      The Trustee appointed under the Plan and Trust shall acknowledge and
      accept its appointment by signing this Document or by signing a separate
      document of acceptance which incorporates the Plan and Trust by reference.
      The Trustee's acknowledgment or acceptance of any modification of this
      Document shall be necessary if such modification changes the duties of the
      Trustee in any way.

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<PAGE>

                                XIX. CONSTRUCTION

This Agreement shall be construed in accordance with the Code, ERISA and
regulations issued thereunder and, to the extent not superseded thereby, the
laws of the State of Washington.

Immunex Corporation Profit Sharing 401(k) Plan and Trust              Page XIX-1

<PAGE>

                            XX. LIABILITY OF TRUSTEE

20.1   Actions of Trustee Conclusive

       In the performance of its duties under the Trust, the Trustee shall
       exercise good faith and comply with the standard of care imposed upon it
       and with the terms of this Agreement. The Trustee shall have the
       authority to interpret its responsibilities hereunder, and, in the
       absence of fraud or breach of fiduciary responsibility, the Trustee's
       interpretation shall be conclusive. In case any dispute or doubt arises
       as to the Trustee's rights, liabilities or duties hereunder, the Trustee
       may employ counsel and take the advice of such counsel as it may select
       and shall be fully protected in acting upon and following such advice,
       except to the extent otherwise provided by law. The Trustee shall be
       entitled to reimburse itself from the Trust Fund for reasonable expenses
       thereby incurred, to the extent such expenses are not paid by the
       Employer.

20.2   Distributions by Trustee

       Until the Trustee receives written notice of any agreement or occurrence
       having effect upon any rights hereunder, including but not limited to
       birth, marriage, divorce, death and/or agreements between Spouses, the
       Trustee shall incur no liability for distributions made.

20.3   Expenses of Administration

       In the event the Employer files for reorganization or protection from
       creditors under the bankruptcy laws, or files a petition in bankruptcy,
       or an assignment of assets for creditors, the Trustee shall pay from
       Trust assets any unpaid expenses for services rendered to the Plan,
       including but not limited to administration, actuarial and consulting
       services.

20.4   Indemnity of Trustee

       The Employer shall indemnify and hold harmless the Trustee from any loss
       or liability (including reasonable attorneys' fees) incurred as a result
       of (a) following any direction (or not acting in the absence of
       direction) from the Employer, the Plan Administrator, an Investment
       Manager, or any other person authorized by the Employer to issue
       direction to the Trustee; and (b) its good faith performance of its
       duties hereunder, except for its own negligence, breach of fiduciary
       duty, or willful misconduct.

Immunex Corporation Profit Sharing 401(k) Plan and Trust               Page XX-1

<PAGE>

                     XXI. RESIGNATION OR REMOVAL OF TRUSTEE

21.1   Resignation

       The Trustee may resign at any time by giving the Employer at least sixty
       (60) days written notice of such resignation sent by registered mail. In
       such event, the Employer shall designate a successor Trustee within sixty
       (60) days, and failing in which, the Trustee may petition an appropriate
       court to designate a successor Trustee, which successor Trustee may be a
       corporate Trustee or an individual Trustee.

21.2   Removal

       The Employer may remove a Trustee with or without cause by giving the
       Trustee at least sixty (60) days' written notice and by appointing a
       successor Trustee, Trustees, corporate or individual, or any combination
       of Trustees.

21.3   Settlement of Account

       Upon the resignation or removal of the Trustee, all right, title and
       interest of such Trustee in the assets of the Trust and all rights and
       privileges under this Agreement theretofore vested in such Trustee, shall
       vest in the successor Trustee, and thereupon, all future liability of
       such Trustee shall terminate; provided, however, that the Trustee shall
       execute, acknowledge and deliver all documents and written instruments
       which are necessary to transfer and convey the right, title and interest
       in the Trust assets and all rights and privileges to the successor
       Trustee.

Immunex Corporation Profit Sharing 401(k) Plan and Trust              Page XXI-1

<PAGE>

                                   XXII. SUITS

If any person or party to this Agreement shall request the Trustee to bring any
action at law or suit in equity to determine any of the provisions or rights
arising out of this Agreement, the Trustee shall not be obligated to bring such
suit unless the Trustee is fully indemnified for all costs of such action,
including a reasonable sum for attorneys' fees.

Immunex Corporation Profit Sharing 401(k) Plan and Trust             Page XXII-1

<PAGE>

                        XXIII. MERGERS AND CONSOLIDATIONS

In the case of any merger or consolidation with any other plan or a transfer of
assets or liabilities to any other plan, each Participant shall be entitled to
be credited with a benefit immediately after such merger, consolidation or
transfer which is equal to the benefit to which he would have been entitled
immediately before such merger or consolidation had the Plan then terminated.

Immunex Corporation Profit Sharing 401(k) Plan and Trust            Page XXIII-1

<PAGE>

                     XXIV AMENDMENT AND TERMINATION OF PLAN

24.1   Right to Amend and Terminate

       The Employer represents that the Plan is intended to be a continuing and
       permanent program for Participants but reserves the right to terminate
       the Plan at any time. The Employer may modify, alter or amend the Plan in
       whole or in part, at any time and for any reason.

24.2   No Revesting

       No termination, modification, alteration or amendment shall have the
       effect of revesting in the Employer any of its contributions or the
       income derived therefrom.

24.3   Exclusive Benefit of Participants

       At no time during the existence hereof or at its termination may the Plan
       assets be used for or directed to purposes other than for the exclusive
       benefit of Participants or their Beneficiaries.

24.4   Termination and Discontinuance of Contributions

       The Employer shall have the right, at any time, to discontinue its
       contributions hereunder and to terminate, or partially terminate, this
       Agreement (and the Plan and Trust established hereunder). Upon complete
       discontinuance of the Employer's contributions or full or partial
       termination of the Plan, the Accounts and rights to benefits of all
       affected Participants shall become fully vested and shall not thereafter
       be subject to forfeiture, except to the extent that law or regulations
       may preclude such vesting in order to prevent discrimination in favor of
       Highly Compensated Employees. Upon final termination of the Plan, the
       Plan Administrator shall direct the Trustee to distribute to the
       Participants all assets remaining in the Trust after payment of any
       expenses properly chargeable against the Trust in accordance with the
       value credited to such Participants, as of the date of such termination,
       in cash or in kind and in such manner as the Plan Administrator shall
       determine.

Immunex Corporation Profit Sharing 401(k) Plan and Trust             Page XXIV-1

<PAGE>

                        XXV. RIGHT TO DISCHARGE EMPLOYEES

Neither the establishment of the Plan, nor any modification thereof, nor the
payment of any benefit shall be construed as giving any Participant or any other
person any legal or equitable right against the Employer or the Trustee, unless
the same shall be specifically provided for in the Plan, nor as giving any
Employee or Participant the right to be retained in the employ of the Employer.
All Employees shall remain subject to discharge by the Employer to the same
extent as if the Plan had never been adopted.

Immunex Corporation Profit Sharing 401(k) Plan and Trust              Page XXV-1

<PAGE>

                          XXVI. RETURN OF CONTRIBUTIONS

26.1  Mistake of Fact

      In the event a contribution is made by reason of a mistake of fact, the
      amount that would not have been contributed had the mistake not occurred
      may be returned to the Employer if the amount is returned within one year
      of the mistaken contribution.

26.2  Allowance of Deductibility

      All contributions to the Plan are conditioned upon their deductibility
      under Code Section 404. Notwithstanding any provision herein to the
      contrary, to the extent a deduction is disallowed, the deduction shall be
      returned to the Employer if the Employer so requests and the amount is
      returned within one year of the disallowance.

Immunex Corporation Profit Sharing 401(k) Plan and Trust             Page XXVI-1

<PAGE>

                               XXVII. PUERTO RICO

To the extent Puerto Rican law imposes different limits or requirements than
those set forth above for plan qualification, the terms and provisions of the
Plan shall be deemed to have been modified to reflect those limits and
requirements with respect to any Eligible Employees employed in Puerto Rico.

Immunex Corporation Profit Sharing 401(k) Plan and Trust            Page XXVII-2

<PAGE>

      IN WITNESS WHEREOF, the parties hereto have caused this Document to be
executed this 25th day of February, 2002.

                                            IMMUNEX CORPORATION

                                            By: /s/ David A. Mann
                                                --------------------------------
                                               Title Executive Vice President
                                                     ---------------------------
                                                     and Chief Financial Officer
                                                     ---------------------------

                                            SECURITY TRUST COMPANY, as Trustee

                                            By: /s/ Nicole McDermott
                                                --------------------------------
                                               Title Vice President
                                                     ---------------------------

Immunex Corporation Profit Sharing 401(k) Plan and Trust            Page XXVII-3

<PAGE>

                                 AMENDMENT NO. 1
                                       TO
                               IMMUNEX CORPORATION
                      PROFIT SHARING 401(k) PLAN AND TRUST

     This Amendment No. 1 is made to the Immunex Corporation Profit Sharing
401(k) Plan and Trust (the "Plan"), which was originally effective January 1,
1987, and most recently amended and restated effective January 1, 2000. All
terms defined in the Plan shall have the same meaning when used herein. All
provisions of the Plan not amended by this Amendment No. 1 shall remain in full
force and effect.

     Effective March 1, 2002, the first sentence of Section 4.1A is amended to
read as follows:

          Each Participant may elect, effective as of the first day of any
     month coincident with or following the Participant's Enrollment Date, by
     filing a Salary Deferral Agreement with the Plan Administrator within
     such time as the Plan Administrator may determine, to defer any whole
     percentage of the Participant's Compensation not to exceed 30%, but in
     any event, the amount of deferral shall not exceed the Section 402(g)
     Limit.

     The Employer has caused this Amendment to be executed on the date indicated
below.

                                              IMMUNEX CORPORATION

Dated: February 28, 2002                      By: /s/ Philip Laub
                                                 -------------------------------
                                                 Its: VP, HR
                                                     ---------------------------

<PAGE>

                                 AMENDMENT NO. 2
                                       TO
                               IMMUNEX CORPORATION
                      PROFIT SHARING 401(K) PLAN AND TRUST

     This Amendment No. 2 is made to the Immunex Corporation Profit Sharing
401(k) Plan and Trust (the "Plan"), which was originally effective January 1,
1987, and most recently amended and restated effective January 1, 2000. All
terms defined in the Plan shall have the same meaning when used herein. This
Amendment shall be effective as of the effective date of Amgen Inc.'s
acquisition of Immunex Corporation. All provisions of the Plan not amended by
this Amendment No. 2 shall remain in full force and effect.

     1.  The name of the Plan is hereby changed to the Amgen Inc. Profit Sharing
401(k) Plan and Trust, and all references in the Plan thereto are hereby revised
accordingly. To that end, Section 1.1 is amended to read as follows:

         1.1  Name

              This Plan shall be known as the Amgen Inc. Profit Sharing 401(k)
              Plan and Trust.

     2.  Section 2.6 is amended to read as follows:

         2.6  Board

              "Board" means the Board of Directors of Amgen Inc.

     3.  Sections 2.6 (Code) through 2.35 (Year of Service) are renumbered as
Sections 2.7 through 2.36, respectively, and all references thereto in the Plan
are revised accordingly.

     4.  Effective March 1, 2002, the third sentence of the first paragraph of
Section 2.8 (as renumbered) is amended to read as follows:

         Notwithstanding the foregoing, (i) Compensation shall include
         amounts excludable from the Employee's gross income by reason of
         Code Section 125, 402(e)(3), 402(h) or 403(b), and (ii) solely
         for purposes of Sections 2.27, 4.1A, 4.1E, 4.2A and 5.2A,
         Compensation shall not include commissions or, effective March 1,
         2002, any amounts paid pursuant to the Immunex Corporation
         Retention Plan or the Immunex Corporation Employee Severance
         Plan.

     5.  Section 2.11 (as renumbered) is amended to read as follows:

         2.11 Employer

<PAGE>

          "Employer" means Immunex Corporation (or any successor thereof) and
          any Affiliate that, with the consent of the Board, elects to adopt the
          Plan; provided, that for purposes of Article XV (Administrative
          Committee), Article XXI (Resignation or Removal of Trustee) and
          Article XXIV (Amendment and Termination of Plan), Employer means Amgen
          Inc.

6.   Sections 6.4, 6.5 and 6.6 are amended to read as follows:

     6.4  Voting of Stock Held in Investment Funds

          With respect to each Participant's investment in any Investment Fund,
          other than the Amgen Inc. Common Stock Fund, the Trustee shall vote
          the number of shares credited to each Participant's Account, in each
          case, in a manner that the Trustee believes to be consistent with its
          fiduciary duties under Section 404 of ERISA.

     6.5  Voting of Amgen Stock

          With respect to each Participant's investment in the Amgen Inc. Common
          Stock Fund, before each annual or special meeting of the stockholders
          of Amgen Inc., Amgen Inc. will furnish such Participant with a copy of
          the proxy solicitation material for such meeting, together with a form
          addressed to the Trustee requesting the Participant's confidential
          instructions on how the shares of Amgen Inc. common stock ("Shares")
          allocated to the Participant's Account should be voted on each matter
          to come before the meeting. The number of Shares allocated to a
          Participant's Account will be determined by multiplying the number of
          Shares held in the Amgen Inc. Common Stock Fund as of the applicable
          record date by a fraction, the numerator of which is the number of
          units of such Fund held in the Participant's Account as of the
          applicable record date and the denominator of which is the total
          number of outstanding units of such Fund as of such date. Upon receipt
          of such instructions, the Trustee shall vote Shares allocated to each
          Participant's Account (including fractional as well as whole Shares)
          in accordance with timely directions of such Participant; provided,
          that a failure of a Participant to timely and affirmatively direct the
          manner in which Shares allocated to the Participant's Account are to
          be voted shall be deemed for purposes of this Section to be an
          affirmative direction to abstain from voting.

     6.6  Tender of Amgen Stock

          The Trustee shall, with respect to Shares allocated to that portion of
          each Participant's Account invested in the Amgen Inc. Common Stock

                                     Page 2

<PAGE>

               Fund, act in response to any tender offer or exchange offer for
               Shares commenced by a person or persons, including, but not
               limited to, a tender offer or exchange offer within the meaning
               of the Securities Exchange Act of 1934, as amended from time to
               time (all such tender or exchange offers collectively, a "tender
               offer"), in accordance with timely directions of such
               Participant; provided, that a failure of a Participant to timely
               and affirmatively direct the manner in which the Trustee is to
               act in response to a tender offer with respect to Shares
               allocated to the Participant's Account shall be deemed for
               purposes of this Section to be an affirmative direction not to
               take action with respect to such Shares. For purposes of
               determining the number of Shares to be the subject of any
               particular response to a tender offer, the Trustee shall use the
               nearest practicable date as determined by the Trustee. The number
               of Shares allocated to a Participant's Account will be determined
               by multiplying the number of Shares held in the Amgen Inc. Common
               Stock Fund as of the relevant date by a fraction, the numerator
               of which is the number of units of such Fund held in the
               Participant's Account as of such date and the denominator of
               which is the total number of outstanding units of such Fund as of
               such date. Amgen Inc. and the Trustee each shall use its best
               efforts to timely distribute or to cause to be distributed to
               each Participant such information as is being distributed to
               other stockholders of Amgen Inc. in connection with any such
               tender offer.

     7.   The last sentence of Section 12.1(A) is amended to read as follows:

          Notwithstanding the foregoing, if the Plan Administrator establishes
          an Investment Fund that is designed to invest primarily in the common
          stock of Amgen Inc., a Participant (or Beneficiary, as applicable) may
          elect to receive such whole shares of Amgen Inc. common stock as are
          allocated to that portion of the Participant's vested Accounts that is
          invested in such Investment Fund (with cash for any fractional
          shares), in lieu of receiving cash for such portion of the
          Participant's Accounts.

     8.   The third sentence of Section 15.12 is amended to read as follows:

          In addition, all or a portion of the Plan's assets can be invested in
          "qualifying employer securities," within the meaning of Section
          407(d)(5) of ERISA, including, but not limited to, common stock of
          Amgen Inc.

     The Employer has caused this Amendment No. 2 to be executed on the date
indicated below.

                               IMMUNEX CORPORATION

                                     Page 3

<PAGE>

Dated:   July 12, 2002                      By:   /s/ Edward Fritzky
       -------------------------                --------------------------------
                                                  Its:  Chief Executive Officer
                                                       -------------------------

Accepted:

                                            SECURITY TRUST COMPANY, as Trustee

                                            By:  /s/ Nicole McDermott
                                                --------------------------------
Dated:   July 15, 2002                            Its:  Vice President
       -------------------------                       -------------------------

                                     Page 4<PAGE>

                                                                     Exhibit 4.1

================================================================================

                                 TRUST AGREEMENT

                                     between

                            SLM FUNDING CORPORATION,
                                  as Depositor

                                       and

                 CHASE MANHATTAN BANK USA, NATIONAL ASSOCIATION,
                    not in its individual capacity but solely
                           as Eligible Lender Trustee

                            Dated as of July 1, 2002

================================================================================

<PAGE>

                                TABLE OF CONTENTS
                                -----------------

<TABLE>
<CAPTION>
                                                                                  Page
                                                                                  ----
<S>                                                                               <C>
                                   ARTICLE I
                             DEFINITIONS AND USAGE

SECTION 1.1     Definitions and Usage ..........................................   1

                                   ARTICLE II
                                  ORGANIZATION

SECTION 2.1     Creation of Trust; Name ........................................   1
SECTION 2.2     Office .........................................................   1
SECTION 2.3     Purposes and Powers ............................................   1
SECTION 2.4     Appointment of Eligible Lender Trustee .........................   2
SECTION 2.5     Initial Capital Contribution of Trust Estate ...................   2
SECTION 2.6     Declaration of Trust ...........................................   2
SECTION 2.7     Liability of the Holders of the Excess Distribution
                  Certificate ..................................................   3
SECTION 2.8     Title to Trust Property ........................................   3
SECTION 2.9     Representations, Warranties and Covenants
                  of the Depositor .............................................   3
SECTION 2.10    Intentionally Omitted ..........................................   4

                                   ARTICLE III
            BENEFICIAL OWNERSHIP AND EXCESS DISTRIBUTION CERTIFICATE

SECTION 3.1     Initial Beneficial Ownership ...................................   4
SECTION 3.2     Intentionally Omitted ..........................................   4
SECTION 3.3     Intentionally Omitted ..........................................   4
SECTION 3.4     Intentionally Omitted...........................................   4
SECTION 3.5     Intentionally Omitted...........................................   4
SECTION 3.6     Intentionally Omitted ..........................................   4
SECTION 3.7     Intentionally Omitted ..........................................   5
SECTION 3.8     Corporate Trust Office .........................................   5
SECTION 3.9     Intentionally Omitted ..........................................   5
SECTION 3.10    Intentionally Omitted ..........................................   5
SECTION 3.11    Intentionally Omitted ..........................................   5
SECTION 3.12    Intentionally Omitted ..........................................   5
SECTION 3.13    The Excess Distribution Certificate ............................   5

                                   ARTICLE IV
                       ACTIONS BE ELIGIBLE LENDER TRUSTEE

SECTION 4.1     Prior Notice to the Holder of the Excess Distribution Certificate
                  With Respect to Certain Matters ..............................   8
SECTION 4.2     Action with Respect to Sale of the Trust Student Loans .........   9
SECTION 4.3     Action with Respect to Bankruptcy ..............................   9
SECTION 4.4     Restrictions ...................................................   9
SECTION 4.5     Intentionally Omitted ..........................................   9
</TABLE>

<PAGE>

<TABLE>
<S>                                                                               <C>
                                    ARTICLE V
                   APPLICATION OF TRUST FUNDS; CERTAIN DUTIES

SECTION 5.1     Application of Trust Funds .....................................   9
SECTION 5.2     Method of Payment ..............................................  10
SECTION 5.3     No Segregation of Moneys; No Interest ..........................  10
SECTION 5.4     Reports to the Holder of the Excess Distribution
                  Certificate, the Internal Revenue Service and Others .........  10
SECTION 5.5     Intentionally Omitted ..........................................  10
SECTION 5.6     Intentionally Omitted ..........................................  10

                                   ARTICLE VI
                 AUTHORITY AND DUTIES OF ELIGIBLE LENDER TRUSTEE

SECTION 6.1     General Authority ..............................................  11
SECTION 6.2     General Duties .................................................  11
SECTION 6.3     Action upon Instruction ........................................  12
SECTION 6.4     No Duties Except as Specified in
                  this Agreement or in Instructions ............................  13
SECTION 6.5     No Action Except Under Specified Documents or Instructions .....  13
SECTION 6.6     Restrictions ...................................................  13

                                   ARTICLE VII
                     CONCERNING THE ELIGIBLE LENDER TRUSTEE

SECTION 7.1     Acceptance of Trusts and Duties ................................  13
SECTION 7.2     Intentionally Omitted ..........................................  15
SECTION 7.3     Representations and Warranties .................................  15
SECTION 7.4     Reliance; Advice of Counsel ....................................  16
SECTION 7.5     Not Acting in Individual Capacity ..............................  16
SECTION 7.6     Eligible Lender Trustee Not Liable for Excess
                  Distribution Certificate or Trust Student Loans ..............  16
SECTION 7.7     Eligible Lender Trustee May Own
                  Notes ........................................................  17

                                  ARTICLE VIII
              COMPENSATION AND INDEMNITY OF ELIGIBLE LENDER TRUSTEE

SECTION 8.1     Eligible Lender Trustee's Fees and Expenses ....................  17
SECTION 8.2     Payments to the Eligible Lender Trustee ........................  17
SECTION 8.3     Indemnity ......................................................  17

                                   ARTICLE IX
                         TERMINATION OF TRUST AGREEMENT

SECTION 9.1     Termination of Trust Agreement .................................  18

SECTION 9.2     Dissolution upon Insolvency of the Depositor ...................  18
</TABLE>

                                       3

<PAGE>

<TABLE>
<S>                                                                               <C>
                                    ARTICLE X
        SUCCESSOR ELIGIBLE LENDER TRUSTEES AND ADDITIONAL ELIGIBLE LENDER
                                    TRUSTEES

SECTION 10.1    Eligibility Requirements for Eligible Lender Trustee ...........  19
SECTION 10.2    Resignation or Removal of Eligible Lender Trustee ..............  19
SECTION 10.3    Successor Eligible Lender Trustee ..............................  20
SECTION 10.4    Merger or Consolidation of Eligible Lender Trustee .............  21
SECTION 10.5    Appointment of Co-Eligible Lender Trustee or Separate
                  Eligible Lender ..............................................  21

                                   ARTICLE XI
                                  MISCELLANEOUS

SECTION 11.1    Supplements and Amendments .....................................  22
SECTION 11.2    No Legal Title to Trust Estate in
                  Holders of the Excess Distribution Certificate ...............  23
SECTION 11.3    Limitations on Rights of Others ................................  23
SECTION 11.4    Notices ........................................................  24
SECTION 11.5    Severability ...................................................  24
SECTION 11.6    Separate Counterparts ..........................................  24
SECTION 11.7    Successors and Assigns .........................................  24
SECTION 11.8    No Petition ....................................................  24
SECTION 11.9    No Recourse ....................................................  25
SECTION 11.10   Headings .......................................................  25
SECTION 11.11   Governing Law ..................................................  25

Exhibit A       Reserved
Exhibit B       Reserved
Exhibit C       Form of Excess Distribution Certificate

Annex 1 to Trust Agreement
</TABLE>

                                       4

<PAGE>

     TRUST AGREEMENT dated as of July 1, 2002, between SLM FUNDING CORPORATION,
a Delaware corporation, as the Depositor, and CHASE MANHATTAN BANK USA, NATIONAL
ASSOCIATION, a national banking association, not in its individual capacity but
solely as the Eligible Lender Trustee.

                                   WITNESSETH:

     The Depositor and the Eligible Lender Trustee hereby agree as follows:

                                    ARTICLE I

     SECTION 1.1 Definitions and Usage. Except as otherwise specified herein or
as the context may otherwise require, capitalized terms used but not otherwise
defined herein are defined in Appendix A hereto, which also contains rules as to
usage that shall be applicable herein.

                                   ARTICLE II

                                  Organization

     SECTION 2.1 Creation of Trust; Name. There is hereby created a Trust which
shall be known as "SLM Student Loan Trust 2002-4", in which name the Eligible
Lender Trustee may conduct the business of the Trust, make and execute contracts
and other instruments on behalf of the Trust and sue and be sued. The Trust
shall constitute a business trust within the meaning of Section 3801(a) of the
Delaware Business Trust Act for which the Trustee has filed a certificate of
trust with the Secretary of State of the State of Delaware pursuant to Section
3810(a) of the Delaware Business Trust Act.

     SECTION 2.2 Office. The office of the Trust shall be in care of the
Eligible Lender Trustee at its Corporate Trust Office or at such other address
as the Eligible Lender Trustee may designate by written notice to the Depositor.

     SECTION 2.3 Purposes and Powers. The purpose of the Trust is to engage in
the following activities:

          (i)  to issue the Notes pursuant to the Indenture and the Excess
     Distribution Certificate pursuant to this Agreement and to sell the Notes
     in one or more transactions;

          (ii) with the proceeds of the sale of the Notes, to fund the Reserve
     Account pursuant to Section 2.8.1 of the Administration Agreement, to fund
     the Capitalized Interest Account pursuant to Section 2.8.2 of the
     Administration Agreement, to fund the Collection Account pursuant to
     Section 2.6.C of the Administration Agreement, to make the up-front payment
     under the Interest Rate Cap Swap Confirmation and to purchase the Trust
     Student Loans pursuant to the Sale Agreement, as applicable;

<PAGE>

          (iii) to Grant the Trust Estate to the Indenture Trustee pursuant to
     the Indenture, and to hold, manage and distribute to the holder of the
     Excess Distribution Certificate pursuant to the terms of this Agreement any
     portion of the Trust Estate released from the Lien of, and remitted to the
     Trust pursuant to, the Indenture;

          (iv)  to enter into and perform its obligations under the Basic
     Documents to which it is to be a party;

          (v)   to engage in those activities, including entering into
       agreements, that are necessary, suitable or convenient to accomplish the
       foregoing or are incidental thereto or connected therewith including but
       not limited to entering into and performing its obligations under the
       Swap Agreement to which it is to be a party; and

          (vi)  subject to compliance with the Basic Documents, to engage in
       such other activities as may be required in connection with conservation
       of the Trust Estate and the making of distributions to the Noteholders
       and the others specified in Sections 2.7, 2.8.1 and 2.8.2 of the
       Administration Agreement.

The Trust shall not engage in any activity other than in connection with the
foregoing or other than as required or authorized by the terms of this Agreement
or the other Basic Documents.

     SECTION 2.4 Appointment of Eligible Lender Trustee. The Depositor hereby
appoints the Eligible Lender Trustee as trustee of the Trust, effective as of
the date hereof, to have all the rights, powers and duties set forth herein.

     SECTION 2.5 Initial Capital Contribution of Trust Estate. The Depositor
hereby sells, assigns, transfers, conveys and sets over to the Eligible Lender
Trustee, as of the date hereof, the sum of $100.00. The Eligible Lender Trustee
hereby acknowledges receipt in trust from the Depositor, as of the date hereof,
of the foregoing contribution, which shall constitute the Initial Trust Estate
and shall be deposited in the Collection Account. The Depositor shall pay the
organizational expenses of the Trust as they may arise or shall, upon the
request of the Eligible Lender Trustee, promptly reimburse the Eligible Lender
Trustee for any such expenses paid by the Eligible Lender Trustee.

     SECTION 2.6 Declaration of Trust. The Eligible Lender Trustee hereby
declares that it will hold the Trust Estate in trust upon and subject to the
conditions set forth herein for the use and benefit of the holder of the Excess
Distribution Certificate, subject to the obligations of the Trust under the
other Basic Documents. It is the intention of the parties hereto that the Trust
constitute a business trust under Delaware law and that this Agreement
constitute the governing instrument of such trust. Effective as of the date
hereof, the Eligible Lender Trustee shall have all rights, powers and duties set
forth herein with respect to accomplishing the purposes of the Trust.

     SECTION 2.7 Liability of the Holders of the Excess Distribution
Certificate.

(a)  Notwithstanding the provisions of Section 3803 of the Delaware Business
     Trust

                                       2

<PAGE>

          Act, the Depositor shall be liable directly to and shall indemnify the
          injured party for all losses, claims, damages, liabilities and
          expenses of the Trust (including Expenses, to the extent that the
          assets of the Trust that would remain if all of the Notes were paid in
          full would not be sufficient to pay any such liabilities, or if such
          liabilities in fact are not paid out of the Trust Estate) to the
          extent that the Depositor would be liable if the Trust were a
          partnership under the Delaware Revised Uniform Limited Partnership Act
          in which the Depositor were a general partner; provided, however, that
          the Depositor shall not be liable for any losses incurred by a
          beneficial owner of a Note in its capacity as a holder of limited
          recourse debt or to any holder of the Excess Distribution Certificate.
          In addition, any third party creditors of the Trust (other than in
          connection with the obligations to Noteholders excepted above) shall
          be third party beneficiaries of this paragraph.

     (b)  No holder of the Excess Distribution Certificate (in such capacity)
          shall have any personal liability for any liability or obligation of
          the Trust.

     SECTION 2.8 Title to Trust Property. Legal title to all of the Trust Estate
shall be vested at all times in the Trust as a separate legal entity except
where applicable law in any jurisdiction requires title to any part of the Trust
Estate to be vested in a trustee or trustees, in which case title shall be
deemed to be vested in the Eligible Lender Trustee, a co-trustee and/or a
separate trustee, as the case may be; provided that legal title to the Trust
Student Loans shall be vested at all times in the Eligible Lender Trustee on
behalf of the Trust.

     SECTION 2.9 Representations, Warranties, and Covenants of the Depositor.
The Depositor hereby represents, warrants and covenants to the Eligible Lender
Trustee as follows:

     (a)  The Depositor is duly organized and validly existing as a Delaware
          corporation in good standing under the laws of the State of Delaware,
          with power and authority to own its properties and to conduct its
          business as such properties are currently owned and such business is
          presently conducted.

     (b)  The Depositor has the corporate power and authority to execute and
          deliver this Agreement and to carry out its terms; the Depositor has
          full corporate power and authority to sell and assign the property to
          be sold and assigned to and deposited with the Trust (or with the
          Eligible Lender Trustee on behalf of the Trust) and the Depositor has
          duly authorized such sale and assignment and deposit to the Trust (or
          to the Eligible Lender Trustee on behalf of the Trust) by all
          necessary corporate action; and the execution, delivery and
          performance of this Agreement has been duly authorized by the
          Depositor by all necessary corporate action.

     (c)  This Agreement constitutes a legal, valid and binding obligation of
          the Depositor enforceable in accordance with its terms, subject to
          applicable bankruptcy, insolvency, reorganization and similar laws
          relating to creditors' rights generally and subject to general
          principles of equity.

                                       3

<PAGE>

     (d)  The consummation of the transactions contemplated by this Agreement
          and the fulfillment of the terms hereof do not conflict with, result
          in any breach of any of the terms and provisions of, or constitute
          (with or without notice or lapse of time or both) a default under, the
          Certificate of Incorporation or by-laws of the Depositor, or any
          indenture, agreement or other instrument to which the Depositor is a
          party or by which it is bound; nor result in the creation or
          imposition of any Lien upon any of its properties pursuant to the
          terms of any such indenture, agreement or other instrument (other than
          pursuant to the Basic Documents); nor violate any law or, to the
          Depositor's knowledge, any order, rule or regulation applicable to the
          Depositor of any court or of any Federal or state regulatory body,
          administrative agency or other governmental instrumentality having
          jurisdiction over the Depositor or its properties.

     (e)  The Depositor agrees for the benefit of the Noteholders and the holder
          of the Excess Distribution Certificate that it will comply with each
          of the requirements set forth in Article IX, X, and XII of its
          Certificate of Incorporation and with each of the undertakings set
          forth in Annex I hereto.

     SECTION 2.10 Intentionally Omitted.

                                   ARTICLE III

                            Beneficial Ownership and
                         Excess Distribution Certificate

     SECTION 3.1 Initial Beneficial Ownership. Upon the formation of the Trust
by the contribution by the Depositor pursuant to Section 2.5 and until the
issuance of the Excess Distribution Certificate, the Depositor shall be the sole
beneficial owner of the Trust.

     SECTION 3.2 Intentionally Omitted.

     SECTION 3.3 Intentionally Omitted.

     SECTION 3.4 Intentionally Omitted.

     SECTION 3.5 Intentionally Omitted.

     SECTION 3.6 Intentionally Omitted.

     SECTION 3.7 Intentionally Omitted.

     SECTION 3.8 Corporate Trust Office. The Eligible Lender Trustee initially
designates Christiana Center/OPS4, 500 Stanton Christiana Road, Newark, Delaware
19713, as its principal

                                       4

<PAGE>

Corporate Trust Office, at which it shall act as Trustee of the Trust. The
Eligible Lender Trustee's New York office and its authenticating agent's office
are located at 450 West 33rd Street, 15th Floor, New York, New York 10001,
Attention: Structured Finance Services.

     SECTION 3.9 Intentionally Omitted.

     SECTION 3.10 Intentionally Omitted.

     SECTION 3.11 Intentionally Omitted.

     SECTION 3.12 Intentionally Omitted.

     SECTION 3.13 The Excess Distribution Certificate.

     (a) General. The Excess Distribution Certificate shall be issued without
denomination. The Excess Distribution Certificate shall receive payments as
provided in Sections 2.8.1C.1(F)(ii) and 2.8.2B.2 of the Administration
Agreement. The Excess Distribution Certificate shall be executed on behalf of
the Trust by manual or facsimile signature of an authorized officer of the
Eligible Lender Trustee. An Excess Distribution Certificate bearing the manual
or facsimile signatures of individuals who were, at the time when such
signatures were affixed, authorized to sign on behalf of the Trust, shall be
valid and binding obligations of the Trust, notwithstanding that such
individuals or any of them shall have ceased to be so authorized prior to the
authentication and delivery of such Excess Distribution Certificate or did not
hold such offices at the date of authentication and delivery of such Excess
Distribution Certificate.

     (b) Authentication. Concurrently with the sale of the Trust Student Loans
to the Trust pursuant to the Purchase Agreement, the Eligible Lender Trustee
shall cause the Excess Distribution Certificate to be executed on behalf of the
Trust, authenticated and delivered to or upon the written order of the
Depositor, signed by its chairman of the board, its president or any vice
president, without further action by the Depositor. No Excess Distribution
Certificate shall entitle its holder to any benefit under this Agreement, or
shall be valid for any purpose, unless there shall appear on such Excess
Distribution Certificate a certificate of authentication substantially in the
form set forth in Exhibit C, executed by the Eligible Lender Trustee or JPMorgan
Chase Bank, as the Eligible Lender Trustee's authenticating agent, by manual
signature; such authentication shall constitute conclusive evidence that such
Excess Distribution Certificate shall have been duly authenticated and delivered
hereunder. The Excess Distribution Certificate shall be dated the date of its
authentication. No further Excess Distribution Certificates shall be issued
except pursuant to paragraph (c) or (d) below.

     (c) Registration of Transfer and Exchange. The Excess Distribution
Certificate Registrar shall keep or cause to be kept, at the office or agency
maintained pursuant to paragraph (f) below, an Excess Distribution Certificate
Register in which, subject to such reasonable regulations as it may prescribe,
the Eligible Lender Trustee shall provide for the registration of the Excess
Distribution Certificate and of transfers and exchanges of the Excess
Distribution Certificate as herein provided. Chase Manhattan Bank USA, National
Association shall be the initial Excess

                                       5

<PAGE>

Distribution Certificate Registrar.

     Upon surrender for registration of transfer of the Excess Distribution
Certificate at the office or agency maintained pursuant to paragraph (f) below,
the Eligible Lender Trustee shall execute, authenticate and deliver (or shall
cause JPMorgan Chase Bank as its authenticating agent to authenticate and
deliver), in the name of the designated transferee, a new Excess Distribution
Certificate dated the date of authentication by the Eligible Lender Trustee or
any authenticating agent. At the option of the holder of the Excess Distribution
Certificate, the Excess Distribution Certificate may be exchanged for another
Excess Distribution Certificate upon surrender of the Excess Distribution
Certificate to be exchanged at the office or agency maintained pursuant to
paragraph (f) below.

     An Excess Distribution Certificate presented or surrendered for
registration of transfer or exchange shall be accompanied by a written
instrument of transfer in form satisfactory to the Eligible Lender Trustee and
the Excess Distribution Certificate Registrar duly executed by the holder
thereof or his attorney duly authorized in writing, with such signature
guaranteed by a member firm of the New York Stock Exchange or a commercial bank
or trust company. An Excess Distribution Certificate surrendered for
registration of transfer or exchange shall be cancelled and subsequently
disposed of by the Eligible Lender Trustee in accordance with its customary
practice.

     No service charge shall be made for any registration of transfer or
exchange of the Excess Distribution Certificate, but the Eligible Lender Trustee
or the Excess Distribution Certificate Registrar may require payment of a sum
sufficient to cover any tax or governmental charge that may be imposed in
connection with any transfer or exchange of the Excess Distribution Certificate.

     The preceding provisions of this Section notwithstanding, the Eligible
Lender Trustee shall not be required to make and the Excess Distribution
Certificate Registrar need not register transfers or exchanges of the Excess
Distribution Certificate for a period of 15 days preceding any Distribution Date
with respect to the Excess Distribution Certificate.

     The Excess Distribution Certificate and any beneficial interest in the
Excess Distribution Certificate may not be acquired by (a) employee benefit
plans (as defined in section 3(3) of ERISA) that are subject to the provisions
of Title I of ERISA, (b) plans described in section 4975(e)(1) of the Code,
including individual retirement accounts described in Section 408(a) of the Code
or Keogh plans, or (c) Benefit Plans. By accepting and holding the Excess
Distribution Certificate or an interest therein, the holder thereof shall be
deemed to have represented and warranted that it is not a Benefit Plan, is not
purchasing the Excess Distribution Certificate on behalf of a Benefit Plan and
is not using assets of a Plan to purchase the Excess Distribution Certificate
and to have agreed that if the Excess Distribution Certificate is deemed to be a
plan asset, the holder thereof will promptly dispose of the Excess Distribution
Certificate.

     (d) Mutilated, Destroyed, Lost or Stolen Excess Distribution Certificate.
If (1) the mutilated Excess Distribution Certificate shall be surrendered to the
Excess Distribution Certifi-

                                       6

<PAGE>

cate Registrar, or if the Excess Distribution Certificate Registrar shall
receive evidence to its satisfaction of the destruction, loss or theft of the
Excess Distribution Certificate, and (2) there shall be delivered to the Excess
Distribution Certificate Registrar and the Eligible Lender Trustee such security
or indemnity as may be required by them to save each of them and the Trust
harmless, then in the absence of notice that such Excess Distribution
Certificate shall have been acquired by a bona fide purchaser, the Eligible
Lender Trustee on behalf of the Trust shall execute and the Eligible Lender
Trustee shall authenticate and deliver, in exchange for or in lieu of any such
mutilated, destroyed, lost or stolen Excess Distribution Certificate, a new
Excess Distribution Certificate of like tenor. In connection with the issuance
of any new Excess Distribution Certificate under this Section, the Eligible
Lender Trustee and the Excess Distribution Certificate Registrar may require the
payment of a sum sufficient to cover any tax or other governmental charge that
may be imposed in connection therewith. Any duplicate Excess Distribution
Certificate issued pursuant to this paragraph shall constitute conclusive
evidence of ownership in the Trust, as if originally issued, whether or not the
lost, stolen or destroyed Excess Distribution Certificate shall be found at any
time.

     (e) Persons Deemed Owners. Prior to due presentation of the Excess
Distribution Certificate for registration of transfer, the Eligible Lender
Trustee and the Excess Distribution Certificate Registrar and any agent of
either of them may treat the Person in whose name the Excess Distribution
Certificate shall be registered in the Excess Distribution Certificate Register
as the owner of such Excess Distribution Certificate for the purpose of
receiving distributions thereon and for all other purposes whatsoever, and
neither the Eligible Lender Trustee, the Excess Distribution Certificate
Registrar nor any agent thereof shall be bound by any notice to the contrary.

     (f) Maintenance of Office or Agency. The Eligible Lender Trustee shall
maintain in the Borough of Manhattan, The City of New York, an office or offices
or agency or agencies where the Excess Distribution Certificate may be
surrendered for registration of transfer or exchange and where notices and
demands to or upon the Eligible Lender Trustee in respect of the Excess
Distribution Certificate may be served.

     (g) Appointment of Excess Distribution Certificate Paying Agent. The Excess
Distribution Certificate Paying Agent shall make distributions to the holder of
the Excess Distribution Certificate from the amounts received from the Indenture
Trustee pursuant to Sections 2.8.1C.1F(ii) and 2.8.2B.2 of the Administration
Agreement and shall report the amounts of such distributions to the Eligible
Lender Trustee. Any Excess Distribution Certificate Paying Agent shall have the
revocable power to receive such funds from the Indenture Trustee for the purpose
of making the distributions referred to above. The Eligible Lender Trustee may
revoke such power and remove the Excess Distribution Certificate Paying Agent if
the Eligible Lender Trustee determines in its sole discretion that the Excess
Distribution Certificate Paying Agent shall have failed to perform its
obligations under this Agreement in any material respect. The Excess
Distribution Certificate Paying Agent shall initially be the Eligible Lender
Trustee, and any co-paying agent chosen by the Eligible Lender Trustee and
consented to by the Administrator (which consent shall not be unreasonably
withheld). The co-paying agent shall initially be the Indenture Trustee. The
Eligible Lender Trustee shall be permitted to resign

                                       7

<PAGE>

as Excess Distribution Certificate Paying Agent upon 30 days' written notice to
the Eligible Lender Trustee. In the event that the Eligible Lender Trustee shall
no longer be the Excess Distribution Certificate Paying Agent, the Eligible
Lender Trustee shall appoint a successor to act as Excess Distribution
Certificate Paying Agent (which shall be a bank or trust company). The Eligible
Lender Trustee shall cause such successor Excess Distribution Certificate Paying
Agent or any additional Excess Distribution Certificate Paying Agent appointed
by the Eligible Lender Trustee to execute and deliver to the Eligible Lender
Trustee an instrument in which such successor Excess Distribution Certificate
Paying Agent or additional Excess Distribution Certificate Paying Agent shall
agree with the Eligible Lender Trustee that as Excess Distribution Certificate
Paying Agent, such successor Excess Distribution Certificate Paying Agent or
additional Excess Distribution Certificate Paying Agent will hold all sums, if
any, held by it for payment to the holder of the Excess Distribution Certificate
in trust for the benefit of such holder until such sums shall be paid to such
holder. The Excess Distribution Certificate Paying Agent shall return all
unclaimed funds to the Eligible Lender Trustee and upon removal of an Excess
Distribution Certificate Paying Agent such Excess Distribution Certificate
Paying Agent shall also return all funds in its possession to the Eligible
Lender Trustee. The provisions of Sections 7.1, 7.3, 7.4, 7.5 and 8.1 shall
apply to the Eligible Lender Trustee also in its role as Excess Distribution
Certificate Paying Agent, for so long as the Eligible Lender Trustee shall act
as Certificate Paying Agent and, to the extent applicable, to any other paying
agent appointed hereunder. Any reference in this Agreement to the Excess
Distribution Certificate Paying Agent shall include any co-paying agent unless
the context requires otherwise.

                                   ARTICLE IV

                       Actions by Eligible Lender Trustee

     SECTION 4.1 Prior Notice to the Holder of the Excess Distribution
Certificate With Respect to Certain Matters. With respect to the following
matters, the Eligible Lender Trustee shall not take action unless at least 30
days before the taking of such action, the Eligible Lender Trustee shall have
notified the holder of the Excess Distribution Certificate and each of the
Rating Agencies in writing of the proposed action and the holder shall not have
notified the Eligible Lender Trustee in writing prior to the 30th day after such
notice is given that it has withheld consent or provided alternative direction:

     (a)  the initiation of any material claim or lawsuit by the Trust (except
          claims or lawsuits brought in connection with the collection of the
          Trust Student Loans) and the compromise of any material action, claim
          or lawsuit brought by or against the Trust (except with respect to the
          aforementioned claims or lawsuits for collection of Trust Student
          Loans);

     (b)  the amendment of the Indenture by a supplemental indenture in
          circumstances where the consent of any class of Noteholders is
          required;

     (c)  the amendment of the Indenture by a supplemental indenture in
          circumstances

                                       8

<PAGE>

          where the consent of any class of Noteholder is not required and such
          amendment materially adversely affects the interest of the holder of
          the Excess Distribution Certificate; or

     (d)  the amendment of the Swap Agreement in circumstances where the consent
          of any class of Noteholders is required or in circumstances where the
          consent of Noteholders is not required but where such amendment
          materially adversely affects the interest of the holder of the Excess
          Distribution Certificate.

     SECTION 4.2 Action with Respect to Sale of the Trust Student Loans. The
Eligible Lender Trustee shall not have the power, except upon the written
direction of the Depositor and except as expressly provided in the Basic
Documents, to sell the Trust Student Loans after the payment in full of the
Notes.

     SECTION 4.3 Action with Respect to Bankruptcy. The Eligible Lender Trustee
shall not have the power to commence a voluntary proceeding in bankruptcy
relating to the Trust without the prior approval of the Depositor and the
delivery to the Eligible Lender Trustee by the Depositor of a certificate
certifying that the Depositor reasonably believes that the Trust is insolvent.

     SECTION 4.4 Restrictions. Neither the Depositor nor the holder of the
Excess Distribution Certificate shall direct the Eligible Lender Trustee to take
or refrain from taking any action if such action or inaction would be contrary
to any obligation of the Trust or the Eligible Lender Trustee under this
Agreement or any of the other Basic Documents or would be contrary to Section
2.3 nor shall the Eligible Lender Trustee be permitted to follow any such
direction, if given.

     SECTION 4.5 Intentionally Omitted.

                                    ARTICLE V

                   Application of Trust Funds; Certain Duties

     SECTION 5.1 Application of Trust Funds.

     (a)  On each Distribution Date, the Eligible Lender Trustee shall
          distribute to the holder of the Excess Distribution Certificate any
          amounts payable in respect of the Excess Distribution Certificate in
          accordance with the Administrative Agreement.

     (b)  In the event that any withholding tax is imposed on the Trust's
          payment to the holder of the Excess Distribution Certificate, such tax
          shall reduce the amount otherwise distributable on the Excess
          Distribution Certificate.

     SECTION 5.2 Method of Payment. Subject to Section 9.1(c), distributions
required to

                                       9

<PAGE>

be made to the holder of the Excess Distribution Certificate on any Distribution
Date shall be made to the holder of record on the preceding Record Date either
by wire transfer, in immediately available funds, to the account of such holder
at a bank or other entity having appropriate facilities therefor, if such holder
shall have provided to the Excess Distribution Certificate Registrar appropriate
written instructions signed by two authorized officers, if any, at least five
Business Days prior to such Distribution Date, or, if not, by check mailed to
such holder at the address of such holder appearing in the Excess Distribution
Certificate Register.

     SECTION 5.3 No Segregation of Moneys; No Interest. Subject to Section 5.1,
moneys received by the Eligible Lender Trustee hereunder need not be segregated
in any manner except to the extent required by law or the Administration
Agreement and may be deposited under such general conditions as may be
prescribed by law, and the Eligible Lender Trustee shall not be liable for any
interest thereon.

     SECTION 5.4 Reports to the Holder of the Excess Distribution Certificate,
the Internal Revenue Service and Others. The Eligible Lender Trustee shall
provide (or cause to be provided) any reports or other information required to
be provided to the holder of the Excess Distribution Certificate pursuant to the
Code, the regulations promulgated thereunder or other applicable law. In
addition, the Eligible Lender Trustee shall provide (or cause to be provided)
any information concerning the Excess Distribution Certificate to the Internal
Revenue Service or other taxing authority as required under the Code, the
regulations promulgated thereunder or other applicable law. The Eligible Lender
Trustee shall be entitled to hire an independent accounting firm to perform the
functions described in this Section 5.4, the reasonable fees and expenses of
which shall be paid by the Depositor.

     SECTION 5.5 Intentionally Omitted.

     SECTION 5.6 Intentionally Omitted.

                                       10

<PAGE>

                                   ARTICLE VI

                 Authority and Duties of Eligible Lender Trustee

     SECTION 6.1 General Authority. The Eligible Lender Trustee is authorized
and directed to execute and deliver the Basic Documents to which the Trust is to
be a party and each certificate or other document attached as an exhibit to or
contemplated by the Basic Documents to which the Trust is to be a party, in each
case, in such form as the Depositor shall approve as evidenced conclusively by
the Eligible Lender Trustee's execution thereof, and, on behalf of the Trust, to
direct the Indenture Trustee to authenticate and deliver Notes in the aggregate
principal amount of $1,532,453,000. The Eligible Lender Trustee is also
authorized and directed on behalf of the Trust (i) to acquire and hold legal
title to the Trust Student Loans from the Depositor and (ii) to take all actions
required pursuant to Section 3.2C of the Administration Agreement and otherwise
follow the direction of and cooperate with the Servicer in submitting, pursuing
and collecting any claims to and with the Department with respect to any
Interest Subsidy Payments and Special Allowance Payments relating to the Trust
Student Loans.

     In addition to the foregoing, the Eligible Lender Trustee is authorized to
take all actions required of the Trust pursuant to the Basic Documents. The
Eligible Lender Trustee is further authorized from time to time to take such
action as the Administrator directs or instructs with respect to the Basic
Documents and is directed to take such action to the extent that the
Administrator is expressly required pursuant to the Basic Documents to cause the
Eligible Lender Trustee to act.

     SECTION 6.2 General Duties. It shall be the duty of the Eligible Lender
Trustee to discharge (or cause to be discharged) all its responsibilities
pursuant to the terms of this Agreement, the other Basic Documents to which the
Trust is a party and to administer the Trust in the interest of the Noteholders
and the holder of the Excess Distribution Certificate subject to and in
accordance with the provisions of this Agreement and the other Basic Documents.
Without limiting the foregoing, the Eligible Lender Trustee shall on behalf of
the Trust file and prove any claim or claims that may exist on behalf of the
Trust against the Depositor in connection with any claims paying procedure as
part of an insolvency or a receivership proceeding involving the Depositor.
Notwithstanding the foregoing, the Eligible Lender Trustee shall be deemed to
have discharged its duties and responsibilities hereunder and under the other
Basic Documents to the extent the Administrator has agreed in the Administration
Agreement to perform and act or to discharge any duty of the Eligible Lender
Trustee hereunder or under any other Basic Document, and the Eligible Lender
Trustee shall not be held liable for the default or failure of the Administrator
to carry out its obligations under the Administration Agreement. Except as
expressly provided in the Basic Documents, the Eligible Lender Trustee shall
have no obligation to administer, service or collect the Trust Student Loans or
to maintain, monitor or otherwise supervise the administration, servicing or
collection of the Trust Student Loans.

                                       11

<PAGE>

     SECTION 6.3 Action upon Instruction.

     (a)  [Reserved]

     (b)  The Eligible Lender Trustee shall not be required to take any action
          hereunder or under any other Basic Document if the Eligible Lender
          Trustee shall have reasonably determined, or shall have been advised
          by counsel, that such action is likely to result in liability on the
          part of the Eligible Lender Trustee or is contrary to the terms
          hereof, any other Basic Document or is otherwise contrary to law.

     (c)  Whenever the Eligible Lender Trustee is unable to determine the
          appropriate course of action between alternative courses and actions
          permitted or required by the terms of this Agreement or under any
          other Basic Document, the Eligible Lender Trustee shall promptly give
          notice (in such form as shall be appropriate under the circumstances)
          to the Depositor requiring instruction as to the course of action to
          be adopted, and to the extent the Eligible Lender Trustee acts in good
          faith in accordance with any written instruction of the Depositor
          received, the Eligible Lender Trustee shall not be liable on account
          of such action to any Person. If the Eligible Lender Trustee shall not
          have received appropriate instruction within 10 days of such notice
          (or within such shorter period of time as reasonably may be specified
          in such notice or may be necessary under the circumstances) it may,
          but shall be under no duty to, take or refrain from taking such
          action, not inconsistent with this Agreement, the other Basic
          Documents, as it shall deem to be in the best interests of the
          Depositor, and shall have no liability to any Person for such action
          or inaction.

     (d)  In the event that the Eligible Lender Trustee is unsure as to the
          application of any provision of this Agreement, any other Basic
          Document or any such provision is ambiguous as to its application, or
          is, or appears to be, in conflict with any other applicable provision,
          or in the event that this Agreement permits any determination by the
          Eligible Lender Trustee or is silent or is incomplete as to the course
          of action that the Eligible Lender Trustee is required to take with
          respect to a particular set of facts, the Eligible Lender Trustee may
          give notice (in such form as shall be appropriate under the
          circumstances) to the Depositor requesting instruction and, to the
          extent that the Eligible Lender Trustee acts or refrains from acting
          in good faith in accordance with any such instruction received, the
          Eligible Lender Trustee shall not be liable, on account of such action
          or inaction, to any Person. If the Eligible Lender Trustee shall not
          have received appropriate instruction within 10 days of such notice
          (or within such shorter period of time as reasonably may be specified
          in such notice or may be necessary under the circumstances) it may,
          but shall be under no duty to, take or refrain from taking such
          action, not inconsistent with this Agreement or the other Basic
          Documents, as it shall deem to be in the best interest of the holder
          of the Excess Distribution Certificate, and shall have no liability to
          any Person for such action or inaction.

                                       12

<PAGE>

     SECTION 6.4 No Duties Except as Specified in this Agreement or in
Instructions. The Eligible Lender Trustee shall not have any duty or obligation
to manage, make any payment with respect to, register, record, sell, service,
dispose of or otherwise deal with the Trust Estate, or to otherwise take or
refrain from taking any action under, or in connection with, any document
contemplated hereby to which the Eligible Lender Trustee is a party, except as
expressly provided by the terms of this Agreement or in any document or written
instruction received by the Eligible Lender Trustee pursuant to Section 6.3; and
no implied duties or obligations shall be read into this Agreement or any other
Basic Document against the Eligible Lender Trustee. The Eligible Lender Trustee
shall have no responsibility for filing any financing or continuation statement
in any public office at any time or to otherwise perfect or maintain the
perfection of any security interest or lien granted to it hereunder or to
prepare or file any Commission filing for the Trust or to record this Agreement
or any other Basic Document. The Eligible Lender Trustee nevertheless agrees
that it will, at its own cost and expense, promptly take all action as may be
necessary to discharge any Liens on any part of the Trust Estate that result
from actions by, or claims against, Chase Manhattan Bank USA, National
Association in its individual capacity or as the Eligible Lender Trustee that
are not related to the ownership or the administration of the Trust Estate.

     SECTION 6.5 No Action Except Under Specified Documents or Instructions. The
Eligible Lender Trustee shall not otherwise deal with any part of the Trust
Estate except (i) in accordance with the powers granted to and the authority
conferred upon the Eligible Lender Trustee pursuant to this Agreement, (ii) in
accordance with the other Basic Documents to which it is a party and (iii) in
accordance with any document or instruction delivered to the Eligible Lender
Trustee pursuant to Section 6.3.

     SECTION 6.6 Restrictions. The Eligible Lender Trustee shall not take any
action (a) that is inconsistent with the purposes of the Trust set forth in
Section 2.3 or (b) that, to the actual knowledge of the Eligible Lender Trustee,
would result in the Trust's becoming taxable as a corporation for Federal income
tax purposes. Neither the Depositor nor the holder of the Excess Distribution
Certificate shall direct the Eligible Lender Trustee to take action that would
violate the provisions of this Section.

                                   ARTICLE VII

                     Concerning the Eligible Lender Trustee

     SECTION 7.1 Acceptance of Trusts and Duties. The Eligible Lender Trustee
accepts the trusts hereby created and agrees to perform its duties hereunder
with respect to such trusts but only upon the terms of this Agreement. The
Eligible Lender Trustee also agrees to disburse all moneys actually received by
it constituting part of the Trust Estate upon the terms of this Agreement and
the other Basic Documents. The Eligible Lender Trustee shall not be answerable
or accountable hereunder or under any other Basic Document under any
circumstances, except (i)

                                       13

<PAGE>

for its own willful misconduct or negligence or (ii) in the case of the
inaccuracy of any representation or warranty contained in Section 7.3 expressly
made by the Eligible Lender Trustee. In particular, but not by way of limitation
(and subject to the exceptions set forth in the preceding sentence):

     (a)  the Eligible Lender Trustee shall not be liable for any error of
          judgment made by a responsible officer of the Eligible Lender Trustee;

     (b)  the Eligible Lender Trustee shall not be liable with respect to any
          action taken or omitted to be taken by it in accordance with the
          direction or instructions of the Administrator, the Depositor or the
          holder of the Excess Distribution Certificate;

     (c)  no provision of this Agreement or any other Basic Document shall
          require the Eligible Lender Trustee to expend or risk funds or
          otherwise incur any financial liability in the performance of any of
          its rights or powers hereunder or under any other Basic Document, if
          the Eligible Lender Trustee shall have reasonable grounds for
          believing that repayment of such funds or adequate indemnity against
          such risk or liability is not reasonably assured or provided to it;

     (d)  under no circumstances shall the Eligible Lender Trustee be liable for
          indebtedness evidenced by or arising under any of the Basic Documents,
          including the principal of and interest on the Notes;

     (e)  the Eligible Lender Trustee shall not be responsible for or in respect
          of the validity or sufficiency of this Agreement or for the due
          execution hereof by the Depositor or for the form, character,
          genuineness, sufficiency, value or validity of any of the Trust Estate
          or for or in respect of the validity or sufficiency of the Basic
          Documents, other than the certificate of authentication on the Excess
          Distribution Certificate, and the Eligible Lender Trustee shall in no
          event assume or incur any liability, duty, or obligation to any
          Noteholder or the holder of the Excess Distribution Certificate, other
          than as expressly provided for herein and in the other Basic
          Documents;

     (f)  the Eligible Lender Trustee shall not be liable for the action or
          inaction, default or misconduct of the Administrator, the Depositor,
          the Indenture Trustee, the Servicer or the Swap Counterparty under any
          of the other Basic Documents or otherwise and the Eligible Lender
          Trustee shall have no obligation or liability to perform the
          obligations of the Trust under this Agreement or the other Basic
          Documents that are required to be performed by the Administrator under
          the Administration Agreement, the Indenture Trustee under the
          Indenture, the Servicer under the Servicing Agreement or the Swap
          Counterparty under the Swap Agreement; and

     (g)  the Eligible Lender Trustee shall be under no obligation to exercise
          any of the rights or powers vested in it by this Agreement, or to
          institute, conduct or defend

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<PAGE>

          any litigation under this Agreement or otherwise or in relation to
          this Agreement, any other Basic Document, at the request, order or
          direction of the Depositor or holder of the Excess Distribution
          Certificate, unless the Depositor or such holder has offered to the
          Eligible Lender Trustee security or indemnity satisfactory to it
          against the costs, expenses and liabilities that may be incurred by
          the Eligible Lender Trustee therein or thereby. The right of the
          Eligible Lender Trustee to perform any discretionary act enumerated in
          this Agreement or in any other Basic Document shall not be construed
          as a duty, and the Eligible Lender Trustee shall not be answerable for
          other than its negligence or willful misconduct in the performance of
          any such act.

     SECTION 7.2 Intentionally Omitted.

     SECTION 7.3 Representations and Warranties. The Eligible Lender Trustee
hereby represents and warrants to the Depositor, for the benefit of the
Noteholders and the holder of the Excess Distribution Certificate, that:

     (a)  It is duly organized and validly existing in good standing under the
          laws of its governing jurisdiction and has an office located within
          the State of Delaware. It has all requisite corporate power and
          authority to execute, deliver and perform its obligations under this
          Agreement.

     (b)  It has taken all corporate action necessary to authorize the execution
          and delivery by it of this Agreement, and this Agreement will be
          executed and delivered by one of its officers who is duly authorized
          to execute and deliver this Agreement on its behalf.

     (c)  Neither the execution nor the delivery by it of this Agreement, nor
          the consummation by it of the transactions contemplated hereby nor
          compliance by it with any of the terms or provisions hereof will
          contravene any Federal or Delaware state law, governmental rule or
          regulation governing the banking or trust powers of the Eligible
          Lender Trustee or any judgment or order binding on it, or constitute
          any default under its charter documents or by-laws or any indenture,
          mortgage, contract, agreement or instrument to which it is a party or
          by which any of its properties may be bound.

     (d)  It is and will maintain its status as an "eligible lender" (as such
          term is defined in Section 435(d) of the Higher Education Act) for
          purposes of holding legal title to the Trust Student Loans as
          contemplated by this Agreement and the other Basic Documents, it has a
          lender identification number with respect to the Trust Student Loans
          from the Department and has and will maintain in effect a Guarantee
          Agreement with each of the Guarantors with respect to the Trust
          Student Loans.

     SECTION 7.4 Reliance; Advice of Counsel.

                                       15

<PAGE>

     (a)  The Eligible Lender Trustee shall incur no liability to anyone in
          acting upon any signature, instrument, direction, notice, resolution,
          request, consent, order, certificate, report, opinion, bond or other
          document or paper believed by it to be genuine and believed by it to
          be signed by the proper party or parties. The Eligible Lender Trustee
          may accept a certified copy of a resolution of the board of directors
          or other governing body of any corporate party as conclusive evidence
          that such resolution has been duly adopted by such body and that the
          same is in full force and effect. As to any fact or matter the method
          of the determination of which is not specifically prescribed herein,
          the Eligible Lender Trustee may for all purposes hereof rely on a
          certificate, signed by the president or any vice president or by the
          treasurer or other authorized officers of the relevant party, as to
          such fact or matter and such certificate shall constitute full
          protection to the Eligible Lender Trustee for any action taken or
          omitted to be taken by it in good faith in reliance thereon.

     (b)  In the exercise or administration of the trusts hereunder and in the
          performance of its duties and obligations under this Agreement or the
          other Basic Documents, the Eligible Lender Trustee (i) may act
          directly or through its agents or attorneys pursuant to agreements
          entered into with any of them and the Eligible Lender Trustee shall
          not be liable for the conduct or misconduct of such agents or
          attorneys if such agents or attorneys shall have been selected by the
          Eligible Lender Trustee with reasonable care, and (ii) may consult
          with counsel and accountants to be selected with reasonable care and
          employed by it. The Eligible Lender Trustee shall not be liable for
          anything done, suffered or omitted in good faith by it in accordance
          with the written opinion or advice of any such counsel or accountants
          and not contrary to this Agreement or any other Basic Document.

     SECTION 7.5 Not Acting in Individual Capacity. Except as provided in this
Article VII, in accepting the trusts hereby created Chase Manhattan Bank USA,
National Association acts solely as Eligible Lender Trustee hereunder and not in
its individual capacity and all Persons having any claim against the Eligible
Lender Trustee by reason of the transactions contemplated by this Agreement or
any other Basic Document shall look only to the Trust Estate for payment or
satisfaction thereof.

     SECTION 7.6 Eligible Lender Trustee Not Liable for Excess Distribution
Certificates or Trust Student Loans. The recitals contained herein and in the
Excess Distribution Certificate (other than the signature of and authentication
by the Eligible Lender Trustee on the Excess Distribution Certificate) shall be
taken as the statements of the Depositor and the Eligible Lender Trustee assumes
no responsibility for the correctness thereof. The Eligible Lender Trustee makes
no representations as to the validity or sufficiency of this Agreement, the
Excess Distribution Certificate, or any other Basic Document (other than the
signature of and authentication by the Eligible Lender Trustee on the Excess
Distribution Certificate), or the Notes, or of any Trust Student Loan or related
documents. The Eligible Lender Trustee shall at no time have any responsibility
(or liability except for willfully or negligently terminating or allowing to be
terminated any of the Guarantee Agreements, in a case where the Eligible Lender
Trustee knows

                                       16

<PAGE>

of any facts or circumstances which will or could reasonably be expected to
result in any such termination) for or with respect to the legality, validity,
enforceability and eligibility for Guarantee Payments, federal reinsurance,
Interest Subsidy Payments or Special Allowance Payments, as applicable, in
respect of any Trust Student Loan, or for or with respect to the sufficiency of
the Trust Estate or its ability to generate the payments to be distributed to
the holder of the Excess Distribution Certificate under this Agreement or the
Noteholders under the Indenture, including the existence and contents of any
computer or other record of any Trust Student Loan; the validity of the
assignment of any Trust Student Loan to the Eligible Lender Trustee on behalf of
the Trust; the completeness of any Trust Student Loan; the performance or
enforcement (except as expressly set forth in any Basic Document) of any Trust
Student Loan; the compliance by the Depositor or the Servicer with any warranty
or representation made under any Basic Document or in any related document or
the accuracy of any such warranty or representation or any action or inaction of
the Administrator, the Indenture Trustee or the Servicer or any subservicer
taken in the name of the Eligible Lender Trustee.

     SECTION 7.7 Eligible Lender Trustee May Own Notes. The Eligible Lender
Trustee in its individual or any other capacity may become the owner or pledgee
of Notes and may deal with the Depositor, the Administrator, the Indenture
Trustee, the Servicer or the Swap Counterparty in banking transactions with the
same rights as it would have if it were not Eligible Lender Trustee.

                                  ARTICLE VIII

              Compensation and Indemnity of Eligible Lender Trustee

     SECTION 8.1 Eligible Lender Trustee's Fees and Expenses. The Eligible
Lender Trustee shall receive as compensation for its services hereunder such
fees as have been separately agreed upon before the date hereof between the
Depositor and the Eligible Lender Trustee, and the Eligible Lender Trustee shall
be entitled to be reimbursed by the Depositor, to the extent provided in such
separate agreement, for its other reasonable expenses (including the reasonable
fees and expenses of counsel and independent accountants) hereunder.

     SECTION 8.2 Payments to the Eligible Lender Trustee. Any amounts paid to
the Eligible Lender Trustee pursuant to Section 8.1 hereof or pursuant to
Section 9 of the Sale Agreement, Section 4.2 of the Administration Agreement or
Section 4.2 of the Servicing Agreement shall be deemed not to be a part of the
Trust Estate immediately after such payment.

     SECTION 8.3 Indemnity. The Depositor shall cause the Administrator to
indemnify the Eligible Lender Trustee in its individual capacity and any of its
officer, directors, employees and agents as and to the extent provided for in
Section 4.2 of the Administration Agreement.

                                       17

<PAGE>

                                   ARTICLE IX

                         Termination of Trust Agreement

     SECTION 9.1 Termination of Trust Agreement.

     (a)  This Agreement (other than Article VIII) and the Trust shall terminate
          and be of no further force or effect upon the earlier of (i) the final
          distribution by the Eligible Lender Trustee of all moneys or other
          property or proceeds of the Trust Estate in accordance with the terms
          of the Indenture, the Administration Agreement and Article V, and (ii)
          the time provided in Section 9.2. The bankruptcy, liquidation,
          dissolution, death or incapacity of the holder of the Excess
          Distribution Certificate, other than the Depositor as described in
          Section 9.2, shall not (x) operate to terminate this Agreement or the
          Trust, nor (y) entitle such holder's legal representatives or heirs to
          claim an accounting or to take any action or proceeding in any court
          for a partition or winding up of all or any part of the Trust or Trust
          Estate nor (z) otherwise affect the rights, obligations and
          liabilities of the parties hereto.

     (b)  Except as provided in Section 9.1(a), none of the Depositor, any
          Noteholder or the holder of the Excess Distribution Certificate shall
          be entitled to revoke or terminate the Trust.

     Upon final distribution of any funds remaining in the Trust, the Eligible
Lender Trustee shall file a certificate of cancellation of the Trust's
certificate of trust pursuant to Section 3810(c) of the Delaware Business Trust
Act.

     SECTION 9.2 Dissolution upon Insolvency of the Depositor. Notwithstanding
the provisions of Section 3808 of the Delaware Business Trust Act, in the event
that an Insolvency Event shall occur with respect to the Depositor, (x) the
Trust created hereunder shall dissolve and (y) this Agreement shall be
terminated in accordance with Section 9.1 90 days after the date of such
Insolvency Event. Promptly after the occurrence of any Insolvency Event with
respect to the Depositor, (i) the Depositor shall give the Indenture Trustee,
the Eligible Lender Trustee, the Swap Counterparty, and each Rating Agency
written notice of such Insolvency Event, and (ii) the Eligible Lender Trustee
shall, upon the receipt of such written notice from the Depositor, give prompt
written notice to the holder of the Excess Distribution Certificate and the
Indenture Trustee, of the occurrence of such event and of the effect of such
event under this Section 9.2; provided, however, that any failure to give a
notice required by this sentence shall not prevent or delay, in any manner, a
termination of the Trust pursuant to the first sentence of this Section 9.2.
Upon a termination of the Trust pursuant to this Section, the Eligible Lender
Trustee shall direct the Indenture Trustee promptly to sell the assets of the
Trust (other than the Trust Accounts) in a commercially reasonable manner and on
commercially reasonable terms. The proceeds of such a sale of the assets of the
Trust shall be treated as collections under the Administration Agreement.

                                       18

<PAGE>

                                    ARTICLE X

                     Successor Eligible Lender Trustees and
                       Additional Eligible Lender Trustees

         SECTION 10.1 Eligibility Requirements for Eligible Lender Trustee. The
Eligible Lender Trustee shall at all times be a corporation or association (i)
qualifying as an "eligible lender" as such term is defined in Section 435(d) of
the Higher Education Act for purposes of holding legal title to the Trust
Student Loans on behalf of the Trust, with a valid lender identification number
with respect to the Trust Student Loans from the Department; (ii) being
authorized to exercise corporate trust powers and hold legal title to the Trust
Student Loans; (iii) having in effect Guarantee Agreements with each of the
Guarantors; (iv) having a combined capital and surplus of at least $50,000,000
and being subject to supervision or examination by Federal or state authorities;
(v) having its principal place of business in the State of Delaware and
otherwise complying with Section 3807 of the Delaware Business Trust Act; and
(vi) having (or having a parent which has) a rating in respect of its long-term
senior unsecured debt of at least BBB- (or the equivalent) by each of the Rating
Agencies (or which, if the long-term senior unsecured debt of such corporation
or association is not rated by any Rating Agency, shall have provided to the
Indenture Trustee written confirmation from such Rating Agency that the
appointment of such corporation or association to serve as Eligible Lender
Trustee will not result in and of itself in a reduction or withdrawal of the
then current rating of any of the Notes). If the Eligible Lender Trustee shall
publish reports of condition at least annually, pursuant to law or to the
requirements of the aforesaid supervising or examining authority, then for the
purpose of this Section, the combined capital and surplus of the Eligible Lender
Trustee shall be deemed to be its combined capital and surplus as set forth in
its most recent report of condition so published. In case at any time the
Eligible Lender Trustee shall cease to be eligible in accordance with the
provisions of this Section, the Eligible Lender Trustee shall resign immediately
in the manner and with the effect specified in Section 10.2.

         SECTION 10.2 Resignation or Removal of Eligible Lender Trustee. The
Eligible Lender Trustee may at any time resign and be discharged from the trusts
hereby created by giving written notice thereof to the Administrator. Upon
receiving such notice of resignation, the Administrator shall promptly appoint a
successor Eligible Lender Trustee meeting the eligibility requirements of
Section 10.1 by written instrument, in duplicate, one copy of which instrument
shall be delivered to the resigning Eligible Lender Trustee and one copy to the
successor Eligible Lender Trustee. If no successor Eligible Lender Trustee shall
have been so appointed and have accepted appointment within 30 days after the
giving of such notice of resignation, the resigning Eligible Lender Trustee may
petition any court of competent jurisdiction for the appointment of a successor
Eligible Lender Trustee; provided, however, that such right to appoint or to
petition for the appointment of any such successor shall in no event relieve the
resigning Eligible Lender Trustee from any obligations otherwise imposed on it
under the Basic Documents until such successor has in fact assumed such
appointment.

         If at any time the Eligible Lender Trustee shall cease to be or shall
be likely to cease to be eligible in accordance with the provisions of Section
10.1 and shall fail to resign after written

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<PAGE>

request therefor by the Administrator, or if at any time an Insolvency Event
with respect to the Eligible Lender Trustee shall have occurred and be
continuing, then the Administrator may remove the Eligible Lender Trustee. If
the Administrator shall remove the Eligible Lender Trustee under the authority
of the immediately preceding sentence, the Administrator shall promptly appoint
a successor Eligible Lender Trustee by written instrument, in duplicate, one
copy of which instrument shall be delivered to the outgoing Eligible Lender
Trustee so removed and one copy to the successor Eligible Lender Trustee and
payment of all fees owed to the outgoing Eligible Lender Trustee.

         Any resignation or removal of the Eligible Lender Trustee and
appointment of a successor Eligible Lender Trustee pursuant to any of the
provisions of this Section shall not become effective until acceptance of
appointment by the successor Eligible Lender Trustee pursuant to Section 10.3,
payment of all fees and expenses owed to the outgoing Eligible Lender Trustee
and the filing of a certificate of amendment to the Trust's certificate of trust
pursuant to Section 3810(b) of the Delaware Business Trust Act. The
Administrator shall provide notice of such resignation or removal of the
Eligible Lender Trustee and to each of the Rating Agencies.

         SECTION 10.3 Successor Eligible Lender Trustee. Any successor Eligible
Lender Trustee appointed pursuant to Section 10.2 shall execute, acknowledge and
deliver to the Administrator and to its predecessor Eligible Lender Trustee an
instrument accepting such appointment under this Agreement, and thereupon the
resignation or removal of the predecessor Eligible Lender Trustee shall become
effective and such successor Eligible Lender Trustee, without any further act,
deed or conveyance, shall become fully vested with all the rights, powers,
duties and obligations of its predecessor under this Agreement, with like effect
as if originally named as Eligible Lender Trustee. The predecessor Eligible
Lender Trustee shall upon payment of its fees and expenses deliver to the
successor Eligible Lender Trustee all documents, statements, moneys and
properties held by it under this Agreement and shall assign, if permissible, to
the successor Eligible Lender Trustee the lender identification number obtained
from the Department on behalf of the Trust; and the Administrator and the
predecessor Eligible Lender Trustee shall execute and deliver such instruments
and do such other things as may reasonably be required for fully and certainly
vesting and confirming in the successor Eligible Lender Trustee all such rights,
powers, duties and obligations.

         No successor Eligible Lender Trustee shall accept such appointment as
provided in this Section unless at the time of such acceptance such successor
Eligible Lender Trustee shall be eligible pursuant to Section 10.1.

         Upon acceptance of appointment by a successor Eligible Lender Trustee
pursuant to this Section, the Administrator shall mail notice of the successor
of such Eligible Lender Trustee to the holder of the Excess Distribution
Certificate, the Indenture Trustee, the Noteholders, the Rating Agencies and the
Swap Counterparty. If the Administrator shall fail to mail such notice within 10
days after acceptance of appointment by the successor Eligible Lender Trustee,
the successor Eligible Lender Trustee shall cause such notice to be mailed at
the expense of the Administrator.

                                       20

<PAGE>

         SECTION 10.4 Merger or Consolidation of Eligible Lender Trustee. Any
corporation into which the Eligible Lender Trustee may be merged or converted or
with which it may be consolidated, or any corporation resulting from any merger,
conversion or consolidation to which the Eligible Lender Trustee shall be a
party, or any corporation succeeding to all or substantially all the corporate
trust business of the Eligible Lender Trustee, shall, without the execution or
filing of any instrument or any further act on the part of any of the parties
hereto, anything herein to the contrary notwithstanding, be the successor of the
Eligible Lender Trustee hereunder; provided that such corporation shall be
eligible pursuant to Section 10.1; and provided further that the Eligible Lender
Trustee shall mail notice of such merger or consolidation to the Rating Agencies
not less than 15 days prior to the effective date thereof.

         SECTION 10.5 Appointment of Co-Eligible Lender Trustee or Separate
Eligible Lender Trustee. Notwithstanding any other provisions of this Agreement,
at any time, for the purpose of meeting any legal requirements of any
jurisdiction in which any part of the Trust may at the time be located, the
Administrator and the Eligible Lender Trustee acting jointly shall have the
power and shall execute and deliver all instruments to appoint one or more
Persons approved by the Eligible Lender Trustee, meeting the eligibility
requirements of clauses (i) through (iii) of Section 10.1, to act as co-trustee,
jointly with the Eligible Lender Trustee, or separate trustee or separate
trustees, of all or any part of the Trust Estate, and to vest in such Person, in
such capacity, such title to the Trust Estate, or any part thereof, and, subject
to the other provisions of this Section, such powers, duties, obligations,
rights and trusts as the Administrator and the Eligible Lender Trustee may
consider necessary or desirable. If the Administrator shall not have joined in
such appointment within 15 days after the receipt by it of a request so to do,
the Eligible Lender Trustee alone shall have the power to make such appointment.
No co-trustee or separate trustee under this Agreement shall be required to meet
the terms of eligibility as a successor trustee pursuant to clauses (iv), (v)
and (vi) of Section 10.1 and no notice of the appointment of any co-trustee or
separate trustee shall be required pursuant to Section 10.3.

         Each separate trustee and co-trustee shall, to the extent permitted by
law, be appointed and act subject to the following provisions and conditions:

                  (i)  all rights, powers, duties, and obligations conferred or
         imposed upon the Eligible Lender Trustee shall be conferred upon and
         exercised or performed by the Eligible Lender Trustee and such separate
         trustee or co-trustee jointly (it being understood that such separate
         trustee or co-trustee is not authorized to act separately without the
         Eligible Lender Trustee joining in such act), except to the extent that
         under any law of any jurisdiction in which any particular act or acts
         are to be performed, the Eligible Lender Trustee shall be incompetent
         or unqualified to perform such act or acts, in which event such rights,
         powers, duties, and obligations (including the holding of title to the
         Trust or any portion thereof in any such jurisdiction) shall be
         exercised and performed singly by such separate trustee or co-trustee,
         solely at the direction of the Eligible Lender Trustee;

                  (ii) no trustee under this Agreement shall be personally
         liable by reason of any act or omission of any other trustee under this
         Agreement; and

                                       21

<PAGE>

                  (iii) the Administrator and the Eligible Lender Trustee acting
         jointly may at any time accept the resignation of or remove any
         separate trustee or co-trustee.

         Any notice, request or other writing given to the Eligible Lender
Trustee shall be deemed to have been given to each of the then separate trustees
and co-trustees, as effectively as if given to each of them. Every instrument
appointing any separate trustee or co-trustee shall refer to this Agreement and
the conditions of this Article. Each separate trustee and co-trustee, upon its
acceptance of the trusts conferred, shall be vested with the estates or property
specified in its instrument of appointment, either jointly with the Eligible
Lender Trustee or separately, as may be provided therein, subject to all the
provisions of this Agreement, specifically including every provision of this
Agreement relating to the conduct of, affecting the liability of, or affording
protection to, the Eligible Lender Trustee. Each such instrument shall be filed
with the Eligible Lender Trustee and a copy thereof given to the Administrator.

         Any separate trustee or co-trustee may at any time appoint the Eligible
Lender Trustee as its agent or attorney-in-fact with full power and authority,
to the extent not prohibited by law, to do any lawful act under or in respect of
this Agreement on its behalf and in its name. If any separate trustee or
co-trustee shall die, become incapable of acting, resign or be removed, all its
estates, properties, rights, remedies and trusts shall vest in and be exercised
by the Eligible Lender Trustee, to the extent permitted by law, without the
appointment of a new or successor trustee.

                                   ARTICLE XI

                                  Miscellaneous

         SECTION 11.1 Supplements and Amendments. This Agreement may be amended
by the Depositor and the Eligible Lender Trustee, with prior written notice to
the Rating Agencies, without the consent of any of the Noteholders or the Swap
Counterparty, to cure any ambiguity, to correct or supplement any provisions in
this Agreement or for the purpose of adding any provisions to or changing in any
manner or eliminating any of the provisions in this Agreement or modifying in
any manner the rights of the Noteholders or the Swap Counterparty; provided,
however, that such action shall not, as evidenced by an Opinion of Counsel,
adversely affect in any material respect the interests of any Noteholder or the
Swap Counterparty.

This Agreement may also be amended from time to time by the Depositor and the
Eligible Lender Trustee, with prior written notice to the Rating Agencies, with
the consent of (i) the Class A Noteholders evidencing not less than a majority
of the Outstanding Amount of the Class A Notes and (ii) the Class B Noteholders
evidencing not less than a majority of the Class B Notes, for the purpose of
adding any provisions to or changing in any manner or eliminating any of the
provisions of this Agreement or modifying in any manner the rights of the Class
A Noteholders or Class B Noteholders, as the case may be; provided, however,
that no such amendment shall (a) increase or reduce in any manner the amount of,
or accelerate or delay the timing of, collections

                                       22

<PAGE>

of payments on Trust Student Loans or distributions that shall be required to be
made for the benefit of the Noteholders or (b) reduce the aforesaid percentage
of the Outstanding Amount of any class of Notes required to consent to any such
amendment, without the consent of all the outstanding Noteholders of such class.

         This Agreement may also be amended from time to time by the Depositor
and the Eligible Lender Trustee, with prior written notice to the Rating
Agencies, with the consent of the Swap Counterparty for the purpose of adding
any provisions to, changing in any manner, or eliminating any of the provisions
of this Agreement or modifying in any manner the rights of the Swap Counterparty
if in the Opinion of Counsel such amendment materially adversely affects the
interests of the Swap Counterparty.

         Promptly after the execution of any such amendment or consent, the
Eligible Lender Trustee shall furnish written notification of the substance of
such amendment or consent to the holder of the Excess Distribution Certificate,
the Indenture Trustee, the Swap Counterparty and each of the Rating Agencies.

         It shall not be necessary for the consent of the Noteholders, the
Indenture Trustee or the Swap Counterparty pursuant to this Section to approve
the particular form of any proposed amendment or consent, but it shall be
sufficient if such consent shall approve the substance thereof. The manner of
obtaining such consents (and any other consents of provided for in this
Agreement or in any other Basic Document) and of evidencing the authorization of
the execution thereof shall be subject to such reasonable requirements as the
Eligible Lender Trustee may prescribe.

         Prior to the execution of any amendment to this Agreement, the Eligible
Lender Trustee shall be entitled to receive and rely upon an Opinion of Counsel
stating that the execution of such amendment is authorized or permitted by this
Agreement. The Eligible Lender Trustee may, but shall not be obligated to, enter
into any such amendment which affects the Eligible Lender Trustee's own rights,
duties or immunities under this Agreement or otherwise.

         SECTION 11.2 No Legal Title to Trust Estate in Holder of the Excess
Distribution Certificate. The holder of the Excess Distribution Certificate
shall not have legal title to any part of the Trust Estate. The holder of the
Excess Distribution Certificate shall be entitled to receive distributions with
respect to its undivided beneficial ownership interest therein only in
accordance with Section 3.13 of this Agreement. No transfer, by operation of law
or otherwise, of any right, title, or interest of the holder of the Excess
Distribution Certificate to and in its beneficial ownership interest in the
Trust Estate shall operate to terminate this Agreement or the trusts hereunder
or entitle any transferee to an accounting or to the transfer to it of legal
title to any part of the Trust Estate.

         SECTION 11.3 Limitations on Rights of Others. Except for Section 2.7,
the provisions of this Agreement are solely for the benefit of the Eligible
Lender Trustee, the Depositor, the holder of the Excess Distribution
Certificate, the Administrator and, to the extent expressly provided herein, the
Indenture Trustee, the Noteholders and the Swap Counterparty, and nothing

                                       23

<PAGE>

in this Agreement (other than Section 2.7), whether express or implied, shall be
construed to give to any other Person any legal or equitable right, remedy or
claim in the Trust Estate or under or in respect of this Agreement or any
covenants, conditions or provisions contained herein.

         SECTION 11.4 Notices. Unless otherwise expressly specified or permitted
by the terms hereof, all notices shall be in writing and shall be deemed given
upon receipt by the intended recipient or three Business Days after mailing if
mailed by certified mail, postage prepaid (except that notice to the Eligible
Lender Trustee shall be deemed given only upon actual receipt by the Eligible
Lender Trustee), if to the Eligible Lender Trustee, addressed to its Corporate
Trust Office; if to the Depositor, addressed to SLM Funding Corporation, 304
South Minnesota Street, Suite B, Carson City, Nevada 89703, or, as to each
party, at such other address as shall be designated by such party in a written
notice to each other party.

         SECTION 11.5 Severability. Any provision of this Agreement that is
prohibited or unenforceable in any jurisdiction shall, as to such jurisdiction,
be ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining provisions hereof, and any such prohibition or
unenforceability in any jurisdiction shall not invalidate or render
unenforceable such provision in any other jurisdiction.

         SECTION 11.6 Separate Counterparts. This Agreement may be executed by
the parties hereto in separate counterparts, each of which when so executed and
delivered shall be an original, but all such counterparts shall together
constitute but one and the same instrument.

         SECTION 11.7 Successors and Assigns. All covenants and agreements
contained herein shall be binding upon to the benefit of, the Depositor and its
successors, the Eligible Lender Trustee and its successors, each holder of the
Excess Distribution Certificate and its successors and permitted assigns, all as
herein provided. Any request, notice, direction, consent, waiver or other
instrument or action by a Noteholder or the holder of the Excess Distribution
Certificate shall bind the successors and assigns of such holder.

         SECTION 11.8 No Petition.

         (a)      The Depositor will not at any time institute against the Trust
                  any bankruptcy proceedings under any United States Federal or
                  state bankruptcy or similar law in connection with any
                  obligations relating to the Excess Distribution Certificate,
                  the Notes, this Agreement or any of the other Basic Documents.

         (b)      The Eligible Lender Trustee (not in its individual capacity
                  but solely as Eligible Lender Trustee), by entering into this
                  Agreement, the holder of the Excess Distribution Certificate
                  by accepting the Excess Distribution Certificate, and the
                  Indenture Trustee and each Noteholder by accepting the
                  benefits of this Agreement, hereby covenant and agree that
                  they will not at any time institute against the Depositor or
                  the Trust, or join in any institution against the Depositor or
                  the Trust of, any bankruptcy, reorganization, arrangement,
                  insolvency, receivership or liquidation proceedings, or other
                  proceedings under any United States

                                       24

<PAGE>

               Federal or state bankruptcy or similar law in connection with any
               obligations relating to the Notes, this Agreement or any of the
               other Basic Documents.

         SECTION 11.9  No Recourse. Each holder of the Excess Distribution
Certificate by accepting the Excess Distribution Certificate acknowledges that
such holder's certificate represents beneficial interests in the Trust only and
do not represent interests in or obligations of the Depositor, the Servicer, the
Administrator, the Eligible Lender Trustee, the Indenture Trustee, the Swap
Counterparty or any Affiliate thereof or any officer, director or employee of
any thereof and no recourse may be had against such parties or their assets,
except as may be expressly set forth or contemplated in this Agreement, the
Excess Distribution Certificate or the other Basic Documents.

         SECTION 11.10 Headings. The headings of the various Articles and
Sections herein are for convenience of reference only and shall not define or
limit any of the terms or provisions hereof.

         SECTION 11.11 Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of Delaware, without
reference to its conflict of law provisions, and the obligations, rights and
remedies of the parties hereunder shall be determined in accordance with such
laws.

                                       25

<PAGE>

         IN WITNESS WHEREOF, the parties hereto have caused this Trust Agreement
to be duly executed by their respective officers hereunto duly authorized, as of
the day and year first above written.

                                    CHASE MANHATTAN BANK USA, NATIONAL
                                    ASSOCIATION,
                                    not in its individual capacity but solely as
                                    Eligible Lender Trustee,

                                    By /s/ JOHN J. CASHIN
                                       ---------------------
                                         Name:  John J. Cashin
                                         Title: Vice President

                                    SLM FUNDING CORPORATION,
                                    as the Depositor,

                                    By /s/ J. LANCE FRANKE
                                       --------------------------------
                                         Name:  J. Lance Franke
                                         Title: Vice President

                                       26

<PAGE>

                                                                       EXHIBIT A
                                                          TO THE TRUST AGREEMENT

                                    RESERVED

                                       1

<PAGE>

                                                                       EXHIBIT B
                                                          TO THE TRUST AGREEMENT

                                    RESERVED

<PAGE>

                                                                       EXHIBIT C
                                                          TO THE TRUST AGREEMENT

                    [FORM OF EXCESS DISTRIBUTION CERTIFICATE]
                      [SEE REVERSE FOR CERTAIN DEFINITIONS]

         THIS EXCESS DISTRIBUTION CERTIFICATE MAY NOT BE ACQUIRED BY OR FOR THE
ACCOUNT OF A BENEFIT PLAN (AS DEFINED BELOW). THIS CERTIFICATE IS NOT GUARANTEED
OR INSURED BY ANY GOVERNMENTAL AGENCY.

                          SLM STUDENT LOAN TRUST 2002-4
                         EXCESS DISTRIBUTION CERTIFICATE

         evidencing a fractional undivided interest in the Trust, as defined
         below, the property of which includes a pool of student loans sold to
         the Trust by SLM Funding Corporation.

         (This Excess Distribution Certificate does not represent an interest in
         or obligation of SLM Funding Corporation, the Servicer (as defined
         below), the Eligible Lender Trustee (as defined below) or any of their
         respective affiliates, except to the extent described below.)

                                       i

<PAGE>

         THIS CERTIFIES THAT SLM Funding Corporation is the registered owner of
a 100% percentage interest in this Excess Distribution Certificate. The SLM
Student Loan Trust 2002-4(the "Trust") was formed under the laws of the State of
Delaware by SLM Funding Corporation, a Delaware corporation (the "Depositor").
The Trust was created pursuant to a Trust Agreement dated as of July 1, 2002
(the "Trust Agreement") between the Depositor and Chase Manhattan Bank USA,
National Association, a national banking association, not in its individual
capacity but solely as eligible lender trustee on behalf of the Trust (the
"Eligible Lender Trustee"), a summary of certain of the pertinent provisions of
which is set forth below. To the extent not otherwise defined herein, the
capitalized terms used herein have the meanings assigned to them in Appendix A
to the Trust Agreement.

         Issued under the Indenture dated as of July 1, 2002, between the Trust
and Deutsche Bank Trust Company Americas, as Indenture Trustee, are Notes
designated as "Floating Rate Student Loan-Backed Notes" (the "Notes"). This
Excess Distribution Certificate is issued under and is subject to the terms,
provisions and conditions of the Trust Agreement, to which Trust Agreement the
holder of this Excess Distribution Certificate by virtue of the acceptance
hereof assents and by which such holder is bound. The property of the Trust
includes a pool of student loans (the "Trust Student Loans"), all moneys paid
thereunder on or after April 8, 2002, certain bank accounts and the proceeds
thereof and certain other rights under the Trust Agreement, the Sale Agreement,
the Purchase Agreement, the Administration Agreement and the Servicing Agreement
and all proceeds of the foregoing.

         To the extent of funds available therefor, amounts owing hereon will be
distributed on the 15th day of each March, June, September and December (or, if
such 15th day is not a Business Day, the next succeeding Business Day) (each a
"Distribution Date"), commencing on September 16, 2002, to the person in whose
name this Excess Distribution Certificate is registered as of the close of
business on the day immediately preceding the Distribution Date (such day the
"Record Date"), in each case to the extent of such holder's fractional and
undivided interest in the amount to be distributed hereon on such Distribution
Date pursuant to Sections 2.8.1C.1(F)(ii) and 2.8.2B.2 of the Administration
Agreement.

         The holder of this Excess Distribution Certificate acknowledges and
agrees that its rights to receive distributions in respect of this Excess
Distribution Certificate are subordinated to the rights of the Noteholders as
described in the Basic Documents.

                                       ii

<PAGE>

         It is the intent of the Depositor, and the holder of this Excess
Distribution Certificate that, for purposes of Federal, state and local income
and franchise and any other income taxes, the Notes will be treated as
newly-issued debt of, and this Excess Distribution Certificate will be treated
as equity in, the Trust. The holder of this Excess Distribution Certificate
agrees to treat, and to take no action inconsistent with the treatment of, this
Excess Distribution Certificate for such tax purposes as equity in the Trust.

         The holder of this Excess Distribution Certificate, by its acceptance
of this Excess Distribution Certificate, covenants and agrees that it will not
at any time institute against the Depositor or the Trust, or join in any
institution against the Depositor or the Trust of, any bankruptcy,
reorganization, arrangement, insolvency, receivership or liquidation
proceedings, or other proceedings under any United States Federal or state
bankruptcy or similar law in connection with any obligations relating to this
Excess Distribution Certificate, the Notes, the Trust Agreement or any of the
other Basic Documents.

         Distributions on this Excess Distribution Certificate will be made as
provided in the Administration Agreement to the holder of record hereof without
the presentation or surrender of this Excess Distribution Certificate or the
making of any notation hereon. Except as otherwise provided in the Trust
Agreement and notwithstanding the above, the final distribution on this Excess
Distribution Certificate will be made after due notice by the Administrator of
the pendency of such distribution and only upon presentation and surrender of
this Excess Distribution Certificate at the office or agency maintained for the
purpose by the Eligible Lender Trustee in the Borough of Manhattan, The City of
New York.

         Reference is hereby made to the further provisions of this Excess
Distribution Certificate set forth on the reverse hereof, which further
provisions shall for all purposes have the same effect as if set forth at this
place.

         Unless the certificate of authentication hereon shall have been
executed by an authorized officer of the Eligible Lender Trustee or its
authenticating agent, by manual signature, this Excess Distribution Certificate
shall not entitle the holder hereof to any benefit under the Trust Agreement or
the Administration Agreement or be valid for any purpose.

                 IN WITNESS WHEREOF, the Eligible Lender Trustee on behalf of

                                      iii

<PAGE>

the Trust and not in its individual capacity has caused this Excess Distribution
Certificate to be duly executed as of the date set forth below.

                                            SLM STUDENT LOAN TRUST 2002-4
                                            by CHASE MANHATTAN BANK USA,
                                            NATIONAL ASSOCIATION, not in its
                                            individual capacity but solely as
                                            Eligible Lender Trustee

                                            By:______________________________
                                                   Authorized Signatory

Date: ______________ ___, 20___

                                       iv

<PAGE>

                     TRUSTEE'S CERTIFICATE OF AUTHENTICATION

This is the Excess Distribution Certificate referred to in the within-mentioned
Trust Agreement.

                                            CHASE MANHATTAN BANK USA, NATIONAL
                                            ASSOCIATION, not in its individual
                                            capacity but solely as Eligible
                                            Lender Trustee,

                                            By:____________________________
                                                  Authorized Signatory

                                            OR

                                            JPMORGAN CHASE BANK, solely in its
                                            capacity as Authenticating Agent for
                                            the Eligible Lender Trustee,

                                            By:__________________________
                                                  Authenticating Agent

Date: __________ ___,200__

                                       v

<PAGE>

                  [Reverse of Excess Distribution Certificate]

         This Excess Distribution Certificate does not represent an obligation
of, or an interest in, the Depositor, Sallie Mae Servicing L.P., as servicer
(the "Servicer"), Student Loan Marketing Association, as administrator (the
"Administrator"), the Eligible Lender Trustee or any affiliates of any of them,
and no recourse may be had against such parties or their assets, except as may
be expressly set forth or contemplated herein, in the Trust Agreement or in the
other Basic Documents. In addition, this Excess Distribution Certificate is not
guaranteed by any governmental agency or instrumentality and is limited in right
of payment to certain collections with respect to the Trust Student Loans, all
as more specifically set forth in the Administration Agreement. A copy of each
of the Trust Agreement, the Sale Agreement, the Purchase Agreement, the
Administration Agreement, the Servicing Agreement and the Indenture may be
examined during normal business hours at the principal office of the
Administrator, and at such other places, if any, designated by the
Administrator, by the holder of this Excess Distribution Certificate upon
request.

         The Trust Agreement permits, with certain exceptions therein provided,
the amendment thereof and the certification of the rights and obligations of the
Depositor and the rights of the holders of this Excess Distribution Certificate
under the Trust Agreement at any time by the Depositor and the Eligible Lender
Trustee with the consent of the holders of the Class A Notes and the Class B
Notes, each voting as a class evidencing not less than a majority of the
outstanding principal balance of each class of the Notes. The Trust Agreement
also permits the amendment thereof, in certain limited circumstances, without
the consent of the Noteholders.

         As provided in the Trust Agreement and subject to certain limitations
therein set forth, the transfer of this Excess Distribution Certificate is
registerable in the Excess Distribution Certificate Register upon surrender of
this Excess Distribution Certificate for registration of transfer at the offices
or agencies maintained by Chase Manhattan Bank USA, National Association in its
capacity as Excess Distribution Certificate Registrar, or by any successor
Excess Distribution Certificate Registrar, in the Borough of Manhattan, The City
of New York, accompanied by a written instrument of transfer in form
satisfactory to the Eligible Lender Trustee and the Excess Distribution
Certificate Registrar duly executed by the holder hereof or such holder's
attorney duly authorized in writing, and thereupon a new Excess Distribution
Certificate will be issued to the designated transferee.

                                       vi

<PAGE>

         As provided in the Trust Agreement and subject to certain limitations
therein set forth, this Excess Distribution Certificate is exchangeable for a
new Excess Distribution Certificate as requested by the holder surrendering the
same. No service charge will be made for any such registration of transfer or
exchange, but the Eligible Lender Trustee or the Excess Distribution Certificate
Registrar may require payment of a sum sufficient to cover any tax or
governmental charge payable in connection therewith.

         The Eligible Lender Trustee, the Certificate Registrar and any agent of
the Eligible Lender Trustee or the Excess Distribution Certificate Registrar may
treat the person in whose name this Excess Distribution Certificate is
registered as the owner hereof for all purposes, and none of the Eligible Lender
Trustee or the Excess Distribution Certificate Registrar or any such agent shall
be affected by any notice to the contrary.

         This Excess Distribution Certificate (including any beneficial interest
herein) may not be acquired by or for the account of (i) an employee benefit
plan (as defined in Section 3(3) of ERISA) that is subject to the provisions of
Title I of ERISA, (ii) a plan described in section 4975(e)(1) of the Internal
Revenue Code of 1986, as amended (the "Code"), including an individual
retirement account described in Section 408(a) of the Code or a Keogh plan or
(iii) any entity whose underlying assets include plan assets by reason of a
plan's investment in the entity (each, a "Benefit Plan"). By accepting and
holding this Excess Distribution Certificate, the holder hereof shall be deemed
to have represented and warranted that it is not a Benefit Plan, it is not
purchasing this Excess Distribution Certificate on behalf of a Benefit Plan, is
not using assets of a Benefit Plan to purchase this Excess Distribution
Certificate and to have agreed that if this Excess Distribution Certificate is
deemed to be a plan asset, the Holder will promptly dispose of this Excess
Distribution Certificate.

         The obligations and responsibilities created by the Trust Agreement and
the Trust created thereby shall terminate upon the payment to Noteholders and
the holder of this Excess Distribution Certificate of all amounts required to be
paid to them pursuant to the Trust Agreement, the Administration Agreement and
the Indenture and the disposition of all property held as part of the Trust. The
Depositor may at its option purchase the corpus of the Trust at a price
specified in the Administration Agreement; however, such right of purchase is
exercisable only on any Distribution Date on or after the date on which the Pool
Balance is less than or equal to 10% of the

                                      vii

<PAGE>

Initial Pool Balance. Any Trust Student Loans remaining in the Trust as of the
end of the Collection Period immediately preceding the Trust Auction Date will
be offered for sale by the Indenture Trustee by auction in accordance with the
procedure described in the Indenture.

         This Excess Distribution Certificate shall be construed in accordance
with the laws of the State of Delaware, without reference to its conflict of law
provisions, and the obligations, rights and remedies of the parties hereunder
shall be determined in accordance with such laws.

                                      viii

<PAGE>

                                   ASSIGNMENT

         FOR VALUE RECEIVED, the undersigned hereby sells, assigns and transfers
unto

PLEASE INSERT SOCIAL SECURITY
OR OTHER IDENTIFYING NUMBER
OF ASSIGNEE

________________________________________________________________________________
(Please print or type name and address, including postal zip code, of assignee)

________________________________________________________________________________
the within Excess Distribution Certificate, and all rights thereunder, hereby
irrevocably constituting and appointing

______________________________________________________________________  Attorney
to transfer said Excess Distribution Certificate on the books of the Excess
Distribution Certificate Registrar, with full power of substitution in the
premises.

Dated:

______________________________*
     Signature Guaranteed:

______________________________*

*      NOTICE: The signature to this assignment must correspond with the name as
it appears upon the face of the within the Excess Distribution Certificate in
every particular, without alteration, enlargement or any change whatever. Such
signature must be guaranteed by a member firm of the New York Stock Exchange or
a commercial bank or trust company.

                                       ix

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