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                                                                    EXHIBIT 10.6

THERAPEUTIC DISCOVERY CORPORATION
Executive Deferral Plan (EDP)
Master Plan Document
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Executive Deferral Plan (EDP)
Master Plan Document
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                              TABLE OF CONTENTS

                                                                            Page
                                                                            ----

Article 1 Definitions . . . . . . . . . . . . . . . . . . . . . . . . . .     1

Article 2 Eligibility . . . . . . . . . . . . . . . . . . . . . . . . . .     5

     2.1  Selection By Committee. . . . . . . . . . . . . . . . . . . . .     5

     2.2  Plan Agreement, Election Form and Beneficiary Election Form . .     5

Article 3 Commitments, Interest and Participation . . . . . . . . . . . .     5

     3.1  Participant Deferral Amount Commitment. . . . . . . . . . . . .     5

     3.2  Deferral Amounts. . . . . . . . . . . . . . . . . . . . . . . .     5

     3.3  Pre-Distribution Crediting Rate . . . . . . . . . . . . . . . .     6

     3.4  Distribution Rate . . . . . . . . . . . . . . . . . . . . . . .     6

     3.5  Termination of Participation. . . . . . . . . . . . . . . . . .     6

     3.6  Unforeseeable Financial Emergency . . . . . . . . . . . . . . .     6

Article 4 7th Year Distribution . . . . . . . . . . . . . . . . . . . . .     7

     4.1  7th Year Distribution . . . . . . . . . . . . . . . . . . . . .     7

     4.2  Timing of Election. . . . . . . . . . . . . . . . . . . . . . .     7

     4.3  Payment of Distribution . . . . . . . . . . . . . . . . . . . .     7

     4.4  Secondary Account Balance . . . . . . . . . . . . . . . . . . .     7

Article 5 Retirement Benefit. . . . . . . . . . . . . . . . . . . . . . .     8

     5.1  Retirement Benefit. . . . . . . . . . . . . . . . . . . . . . .     8

     5.2  Rate of Interest for Retirement Benefit; Vesting. . . . . . . .     8

     5.3  Commencement of Retirement Benefits . . . . . . . . . . . . . .     8

     5.4  Death Prior to Completion of Retirement Benefits. . . . . . . .     8

     5.5  Withdrawal Election . . . . . . . . . . . . . . . . . . . . . .     8

Article 6 Survivor Benefit. . . . . . . . . . . . . . . . . . . . . . . .     9

     6.1  Survivor Benefit. . . . . . . . . . . . . . . . . . . . . . . .     9

     6.2  Amount of Survivor Benefit. . . . . . . . . . . . . . . . . . .     9

     6.3  Benefit Period. . . . . . . . . . . . . . . . . . . . . . . . .     9

     6.4  Eligibility Requirements for Survivor Benefit . . . . . . . . .     9


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Executive Deferral Plan (EDP)
Master Plan Document
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Article 7 Termination Benefit . . . . . . . . . . . . . . . . . . . . . .    10

     7.1  Termination Benefit . . . . . . . . . . . . . . . . . . . . . .    10

     7.2  Primary Account Balance . . . . . . . . . . . . . . . . . . . .    10

     7.3  Secondary Account Balance . . . . . . . . . . . . . . . . . . .    10

     7.4  Payment of Benefit. . . . . . . . . . . . . . . . . . . . . . .    10

Article 8 Disability Benefit. . . . . . . . . . . . . . . . . . . . . . .    11

     8.1  Amount of Disability Benefit. . . . . . . . . . . . . . . . . .    11

Article 9 Beneficiary Designation . . . . . . . . . . . . . . . . . . . .    11

     9.1  Beneficiary Designation . . . . . . . . . . . . . . . . . . . .    11

     9.2  Change of Beneficiary Designation . . . . . . . . . . . . . . .    11

     9.3  No Participant Designation. . . . . . . . . . . . . . . . . . .    11

     9.4  Effect of Payment . . . . . . . . . . . . . . . . . . . . . . .    11

Article 1O Plan Termination, Amendment or Modification. . . . . . . . . .    12

     10.1 Plan Termination. . . . . . . . . . . . . . . . . . . . . . . .    12

     10.2 Amendment or Modification . . . . . . . . . . . . . . . . . . .    12

     10.3 Change in Control . . . . . . . . . . . . . . . . . . . . . . .    12

     10.4 Effect of Payment . . . . . . . . . . . . . . . . . . . . . . .    12

Article 11 Trust. . . . . . . . . . . . . . . . . . . . . . . . . . . . .    13

     11.1 Establishment of the Trust; Premium . . . . . . . . . . . . . .    13

     11.2 Interrelationship of the Plan and the Trust . . . . . . . . . .    13

Article 12 Claims Procedures. . . . . . . . . . . . . . . . . . . . . . .    13

     12.1 Presentation of Claim . . . . . . . . . . . . . . . . . . . . .    13

     12.2 Notification of Decision. . . . . . . . . . . . . . . . . . . .    13

     12.3 Review of a Denied Claim. . . . . . . . . . . . . . . . . . . .    14

     12.4 Decision on Review. . . . . . . . . . . . . . . . . . . . . . .    14

     12.5 Legal Action. . . . . . . . . . . . . . . . . . . . . . . . . .    14


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Executive Deferral Plan (EDP)
Master Plan Document
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Article 13 Miscellaneous. . . . . . . . . . . . . . . . . . . . . . . . .    15

    13.1  Unsecured General Creditor. . . . . . . . . . . . . . . . . . .    15

    13.2  Nonassignability. . . . . . . . . . . . . . . . . . . . . . . .    15

    13.3  Not a Contract of Employment. . . . . . . . . . . . . . . . . .    15

    13.4  Protective Provisions . . . . . . . . . . . . . . . . . . . . .    15

    13.5  Terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . .    15

    13.6  Captions. . . . . . . . . . . . . . . . . . . . . . . . . . . .    16

    13.7  Governing Law . . . . . . . . . . . . . . . . . . . . . . . . .    16

    13.8  Validity. . . . . . . . . . . . . . . . . . . . . . . . . . . .    16

    13.9  Notice. . . . . . . . . . . . . . . . . . . . . . . . . . . . .    16

    13.10 Successors. . . . . . . . . . . . . . . . . . . . . . . . . . .    16

    13.11 Spouse's Interest . . . . . . . . . . . . . . . . . . . . . . .    16

    13.12 Distribution in the Event of Taxation . . . . . . . . . . . . .    17

    13.13 Incompetent . . . . . . . . . . . . . . . . . . . . . . . . . .    17

Article 14 Administration . . . . . . . . . . . . . . . . . . . . . . . .    17

    14.1  Committee Duties. . . . . . . . . . . . . . . . . . . . . . . .    17

    14.2  Agents. . . . . . . . . . . . . . . . . . . . . . . . . . . . .    17

    14.3  Binding Effect of Decision. . . . . . . . . . . . . . . . . . .    18

    14.4  Indemnity of Committee. . . . . . . . . . . . . . . . . . . . .    18

    14.5  Company Information . . . . . . . . . . . . . . . . . . . . . .    18

    14.6  Change in Payments. . . . . . . . . . . . . . . . . . . . . . .    18


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THERAPEUTIC DISCOVERY CORPORATION
Executive Deferral Plan (EDP)
Master Plan Document
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                         THERAPEUTIC DISCOVERY CORPORATION

                              EXECUTIVE DEFERRAL PLAN

                                      Purpose

     The primary purpose of the Executive Deferral Plan (the "EDP" or "Plan") of
Therapeutic Discovery Corporation, a Delaware corporation ("TDC") is to help
attract and maintain high caliber management.  It is the intention of TDC that
the Plan be unfunded for tax purposes and for purposes of Title I of the
Employee Retirement Income Security Act of 1974, as amended.

                                      Article I
                                     Definitions

     For purposes hereof, unless otherwise clearly apparent from the context,
the following phrases or terms shall have the following indicated meanings:

1.1  "Affiliate" shall mean any corporation or entity in which TDC has at least
     twenty-five percent (25%) of the voting control through ownership of equity
     securities or otherwise.

1.2  "Base Rate" shall be the greater of ten percent (10%) or Moody's Seasoned
     Corporate Bond Rate, measured on the November 1 prior to that Plan Year.

1.3  "Beneficiary" shall mean the person or persons, or the entity designated by
     a Participant to receive any benefits payable under this Plan upon the
     death of such Participant.

1.4  "Beneficiary Designation Form" shall mean the form established from time to
     time by the Committee that a Participant completes, signs and returns to
     the Committee to designate one or more Beneficiaries.

1.5  "Bonus Award" shall mean any cash bonus awarded to the Participant under
     the provisions of any of the Company's bonus plans relating to the calendar
     year prior to the Plan Year.  Such Bonus Award shall be credited to the
     Participant's EDP Account as of January 1 of the Plan Year.


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Master Plan Document
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1.6  "Change in Control" shall mean the first to occur of the following events:

     a)  Any "person" (as that term is used in Section 13 and 14(d)(2) of the
         Securities Exchange Act of 1934 ("Exchange Act")) is or becomes the
         beneficial owner (as that term is used in Section 13(d) of the Exchange
         Act), directly or indirectly, of 50% or more of TDC's capital stock
         entitled to vote in the election of directors (however, the option of
         ALZA Corporation ("ALZA") to acquire the shares of TDC (the "Purchase
         Option") shall not be deemed, for purposes of this Plan, to be a
         "Change of Control," unless or until the Purchase Option is
         exercised.);

     b)  During any period of two consecutive years, individuals who at the
         beginning of such period constitute the board of directors of TDC cease
         for any reason to constitute at least a majority thereof, unless the
         election or the nomination for election by TDC's stockholders of each
         new director was approved by a vote of at least three-quarters of the
         directors still in office of TDC who were directors at the beginning of
         the period;

     c)  Any consolidation or merger of TDC, other than a merger of TDC in
         which the holders of the common stock of TDC immediately prior to the
         merger hold more than 50% of the common stock of the surviving
         corporation immediately after the merger;

     d)  The stockholders of TDC approve any plan or proposal for the
         liquidation or dissolution of TDC; or

     e)  Substantially all of the assets of TDC are sold or otherwise
         transferred to parties that are not within a "controlled group of
         corporations" (as defined in Section 1563 of the Internal Revenue Code
         of 1986, as amended) in which TDC is a member.

1.7  "Committee" shall mean the administrative committee appointed to manage and
     administer the Plan in accordance with its provisions pursuant to Article
     14, which Committee shall be the Compensation Committee of the Board of
     Directors unless otherwise determined by the Board of Directors.

1.8  "Company" shall mean Therapeutic Discovery Corporation, a Delaware
     corporation, and any subsidiary or Affiliate thereof.

1.9  "Deferral Amounts" shall mean the amount of Salary and Bonus Award for a
     calendar year deferred by a Participant pursuant to the election made on
     the Election Form.

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Master Plan Document
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1.10 "Disability" shall mean a period of disability during which a Participant
     qualifies for benefits under the Company's group long-term disability plan
     or, if a Participant does not participate in such plan, a period of
     disability during which the Participant would have qualified for benefits
     under such plan had the Participant been a participant in such plan, as
     determined in the sole discretion of the Committee.

1.11 "EDP Account" shall mean the account comprised of the Participant's
     Deferral Amounts and interest credited thereon, which shall be equal to the
     sum of the Primary Account Balance and the Secondary Account Balance.  EDP
     Accounts shall be maintained for each Participant.  A Participant's EDP
     Account shall be utilized solely as a device for the measurement and
     determination of the amounts to be paid to the Participant pursuant to this
     Plan.  A Participant's EDP Account shall not constitute or be treated as a
     trust fund.

1.12 "Election Form" shall mean the form established from time to time by the
     Committee that a Participant completes, signs and returns to the Committee
     to make an election under the Plan.

1.13 "Moody's Seasoned Corporate Bond Rate" shall mean the applicable "Seasoned
     Corporate Bond" rate, which is an arithmetic average of yields of
     representative bonds, including industrials, public utilities, Aaa, Aa, A
     and Baa bonds as published by Moody's Investors Service, Inc. or any
     successor to that service.

1.14 "Participant" shall mean directors of the Company and senior level
     management who are selected for participation in the Plan by the Committee
     and who elect to participate by executing and delivering to the Committee
     the Plan Agreement, the Election Form and the Beneficiary Designation Form.

1.15 "Plan" shall mean the Executive Deferral Plan of the Company, which shall
     be defined by this instrument and by the Plan Agreement, as may be amended
     from time to time.

1.16 "Plan Agreement" shall mean a written agreement, as may be amended from
     time to time, which is entered into by and between the Company and a
     Participant.  Each Plan Agreement executed by a Participant shall provide
     for the entire benefit to which such Participant is entitled to under the
     Plan, and the Plan Agreement bearing the latest date of acceptance by the
     Committee shall govern such entitlement.

1.17 "Plan Year" shall mean calendar year 1996 and subsequent calendar years
     thereafter.

1.18 "Preferred Rate" shall mean 125% of the Base Rate.  The Preferred Rate for
     the 1996 Plan Year shall be twelve and one half percent (12.5%).

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Master Plan Document
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1.19 "Primary Account Balance" shall equal the Participant's Deferral Amounts,
     plus compounded interest credited yearly thereon at the Standard Rate, all
     as determined in accordance with Section 3.3 below.

1.20 "Retirement" and "Retire" shall mean termination of employment or severance
     of a directorship with the Company (i) on or after the attainment of age
     sixty-five (65) or (ii) at a time when the sum of age at last birthday
     ("Rule of 70") plus Years of Service equal 70 or more.

1.21 "Salary" shall mean annual salaries and wages before 401(k) and other
     qualified plan reductions and amounts deferred pursuant to this Plan
     excluding, however, moving allowances, participation in clinical studies,
     income arising from stock option plans, imputed income due to fringe
     benefits, bonuses (including Bonus Awards) or similar items paid to the
     Participant.

1.22 "Secondary Account Balance" shall equal that portion of the cumulative
     interest on the EDP Account, determined in accordance with Section 3.3
     below, that is equal to the sum of (i) the difference between the interest
     on the Primary Account accrued at the Preferred Rate and the interest on
     the Primary Account accrued at the Standard Rate, and (ii) the yearly
     interest at the Preferred Rate on the Secondary Account itself.

1.23 "Standard Rate" shall mean fifty percent (50%) of the Preferred Rate.  The
     Standard Rate for the 1996 Plan Year shall be six and one quarter percent
     (6.25%).

1.24 "Termination of Employment" shall mean the ceasing of employment or
     directorship with the Company, voluntarily or involuntarily, for any reason
     other than Retirement, Disability, or death.  If a Participant is both an
     employee and a Director, a Termination of Employment shall occur only upon
     the termination of the last position held.

1.25 "Trust" shall mean the trust that may be established by the Company, in its
     sole discretion, to which assets may be transferred to for the purpose of
     paying benefits under this Plan.

1.26 "Unforeseeable Financial Emergency" shall mean an unanticipated emergency
     that is caused by an event beyond the control of the Participant that would
     result in severe financial hardship to the Participant resulting from (i) a
     sudden and unexpected illness or accident of the Participant or a dependent
     of the Participant, (ii) a loss of the Participant's property due to
     casualty, or (iii) such other extraordinary and unforeseeable circumstances
     arising as a result of events beyond the control of the Participant, all as
     determined in the sole discretion of the Committee."


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1.27 "Years of Service" shall mean the total number of years in which a
     Participant has been employed by the Company and has completed in each of
     those years 1,000 hours of service.  For purposes of this definition only,
     a year of employment shall be a 365 day period (or 366 day period in the
     case of a leap year) that for the first year of employment commences on the
     employee's date of hiring and that, for any subsequent year, commences on
     an anniversary of that hiring date.  For a non-employee Director
     Participant, "Years of Service" shall mean service as a Director during any
     part of a calendar year.

                                      Article 2
                                     Eligibility

2.1  SELECTION BY COMMITTEE.  The Committee shall have the sole discretion to
     determine the individuals who, in accordance with the purpose of the Plan,
     will be eligible to become Participants.

2.2  PLAN AGREEMENT, ELECTION FORM AND BENEFICIARY ELECTION FORM.  As a
     condition of participation, each Participant shall complete, execute and
     return to the Committee prior to the commencement of the Plan Year for
     which the Participant is to commence participation in the Plan, a Plan
     Agreement, an Election Form and a Beneficiary Designation Form. In
     subsequent Plan Years, a Participant shall complete, execute and return to
     the Committee an Election Form.

                                       Article 3
                       Commitments, Interest and Participation

3.1  PARTICIPANT DEFERRAL AMOUNT COMMITMENT.  Pursuant to the Election Form
     delivered to the Committee prior to the commencement of a Plan Year, the
     Participant may elect for each Plan Year to defer up to fifty percent (50%)
     of his/her Salary and up to one hundred percent (100%), in each case in
     full percentage points, of his/her Bonus Award, subject to the limitations
     of Section 3.2 below.

3.2  DEFERRAL AMOUNTS.  If Salary is deferred by a Participant, the minimum rate
     of deferral shall be $200 per month ($2,400/calendar year) Deferral Amounts
     must be in increments of one hundred dollars ($100).  Bonus Awards may be
     deferred independently of Salary deferrals.


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Master Plan Document
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3.3  PRE-DISTRIBUTION CREDITING RATE.  Subject to the provisions and limitations
     of the Plan, interest shall be credited at the Preferred Rate on the EDP
     Account balance annually on the last day of each Plan Year as though all
     Deferral Amounts, if any, for that Plan Year were made on July 1 of the
     Plan Year. Despite the foregoing, in the event of a Participants death,
     Retirement or Termination of Employment prior to the last day of a Plan
     Year, interest for that Plan Year shall be credited on the EDP Account
     balance up to the day prior to the Participant's death, Retirement or
     Termination of Employment as though all Deferral Amounts, if any, for that
     Plan Year were made on January 1 of the Plan Year.

3.4  DISTRIBUTION RATE.  If, pursuant to the terms of the Plan, a Participant or
     Beneficiary is entitled to receive his or her benefit (other than the 7th
     Year Distribution) in installments, the crediting rate on the undistributed
     portion of the benefits for all periods following the last day of the month
     prior to the date upon which the Participant is no longer an employee or
     Director shall be one of two fixed rates as specified in the Plan.  The
     "Preferred Distribution Rate" shall be composed of the average Preferred
     Rate for the last five (5) Plan Years prior to the commencement of the
     installment payments, including the Plan Year in which the Participant
     terminates employment, or if the Participant has participated in the Plan
     for less than five (5) Plan Years, the average of such rates for the number
     of Plan Years that the Participant has participated in the Plan.  The
     "Standard Distribution Rate" shall be composed of the average Standard Rate
     for the last five (5) Plan Years prior to the commencement of the
     installment payments, including the Plan Year in which the Participant
     terminates employment, or if the Participant has participated in the Plan
     for less than five (5) Plan Years, the average of such rates for the number
     of Plan Years that the Participant has participated in the Plan.

3.5  TERMINATION OF PARTICIPATION.  A Participant who remains an employee or
     director of the Company may not terminate participation in the Plan for any
     reason other than those outlined in Section 3.6, Article 5, Article 6,
     Article 7, Article 8 or Section 10.1.

3.6  UNFORESEEABLE FINANCIAL EMERGENCY.  In the case of Unforeseeable Financial
     Emergency, the Committee may, at its discretion, allow the Participant to
     discontinue deferrals, terminate participation or receive a payout from the
     Plan.  The amount of such payout shall be at the discretion of the
     Committee, provided that such payout shall not exceed the lesser of (i) the
     Participant's EDP Account balance, or (ii) the amount reasonably needed to
     satisfy the Unforeseeable Financial Emergency.


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                                    Article 4
                             7th Year Distribution

4.1  7TH YEAR DISTRIBUTION.  Except as provided in this Article 4, no
     distribution shall be made to a Participant or his or her Beneficiary under
     the Plan until death, Retirement, Disability, Termination of Employment, or
     Unforeseeable Financial Emergency.  In connection with each election to
     defer an annual Deferral Amount (as provided in Section 4.2 below), a
     Participant may elect to receive a future "7th Year Distribution" from the
     Plan with respect to that annual Deferral Amount.

4.2  TIMING OF ELECTION.  Prior to December 31 of the Plan Year immediately
     preceding the Plan Year for which a deferral election is being made, the
     Participant shall elect to:

     a)  receive that Deferral Amount plus interest (as specified below) as a
         7th Year Distribution, or

     b)  leave that Deferral Amount in the EDP Account until such time as
         distributions are required by the other provisions of the Plan.

     Such election shall be made on the Election Form.  If the Participant
     chooses to receive the 7th Year Distribution, he/she shall receive from the
     EDP Account an amount equal to the Primary Account Balance as of the last
     day of the Plan Year that is seven years after the last day of the calendar
     year prior to the first Plan Year in which he or she commences
     participation in the Plan.

4.3  PAYMENT OF DISTRIBUTION.  The payment shall be made in a lump sum within 90
     days of the last day of the Primary Account Balance measurement date
     provided in Section 4.2 above.

4.4  SECONDARY ACCOUNT BALANCE.  If the Primary Account Balance is fully
     distributed in accordance with this Article 4, the Secondary Account
     Balance shall constitute the entire EDP Account and shall be paid in
     accordance with the terms and provisions of this Plan.


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Master Plan Document
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                                    Article 5
                               Retirement Benefit

5.1  RETIREMENT BENEFIT. A Participant who Retires shall become eligible to
     receive, in accordance with this Article, his or her EDP Account (the
     "Retirement Benefit").

5.2  RATE OF INTEREST FOR RETIREMENT BENEFIT; VESTING.  Upon a Participant's
     Retirement, the interest on his/her unpaid EDP Account will be based on
     the Preferred Distribution Rate.  If it has not already done so, a
     Participant's Secondary Account Balance shall vest upon his or her
     Retirement.

5.3  COMMENCEMENT OF RETIREMENT BENEFITS.  Retirement Benefits shall be paid
     over a fifteen (15) year period, payable annually.  Other methods of
     payment shall be at the sole discretion of the Committee.  The initial
     annual Retirement Benefit payment shall commence within thirty (30) days of
     actual Retirement. All subsequent annual payments shall be made prior to
     February 28 of each calendar year thereafter until the Participant's EDP
     Account balance is paid in full.

5.4  DEATH PRIOR TO COMPLETION OF RETIREMENT BENEFITS.  If a retired Participant
     dies before the applicable Retirement Benefit is paid in full, the
     Participant's unpaid Retirement Benefit payments shall continue and be paid
     to that Participant's Beneficiary.

5.5  WITHDRAWAL ELECTION.  A Participant who is eligible to and is receiving a
     Retirement Benefit under the Plan may elect, at any time, to withdraw the
     then remaining unpaid portion of his or her EDP Account balance less a 10%
     withdrawal penalty (the net amount shall be referred to as the "Withdrawal
     Amount").  No partial withdrawals of that balance shall be allowed.  The
     Participant shall make this election by giving the Committee advance
     written notice of the election in a form determined from time to time by
     the Committee.  The penalty shall be equal to 10% of the Participant's
     remaining EDP Account Balance determined immediately prior to the
     withdrawal.  The Participant shall be paid the Withdrawal Amount within 60
     days of his or her election.  Once the Withdrawal Amount is paid, the
     Participant's participation in the Plan shall terminate and the Participant
     shall not be eligible to participate in the Plan in the future.

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                                    Article 6
                                Survivor Benefit

6.1  SURVIVOR BENEFIT.  If a Participant dies before Retirement, Termination of
     Employment or a Disability, the Company will pay the benefit described in
     this Article (the "Survivor's Benefit") to the designated Beneficiary of
     the Participant, in lieu of the Retirement Benefits.

6.2  AMOUNT OF SURVIVOR BENEFIT.  The Survivor Benefit shall equal the existing
     EDP Account Balance at the time of death.

6.3  BENEFIT PERIOD.  The Survivor Benefit shall be paid in a lump sum or over a
     period of time not to exceed 15 years, with interest credited on the unpaid
     balance at the Standard Distribution Rate, as follows:

              Balance of EDP Account       Payment
             ------------------------    -----------
             Up to $100,000             One Lump Sum
             $100,001 - $250,000           5 Years
             $250,001 - $500,000          10 Years
             $500,001 or More             15 Years

     The Committee shall have the sole discretion to decide the number of
benefit payments.  The lump sum payment, or the initial installment payment, of
the Survivor Benefit shall commence within ninety (90) days of the Participant's
death.  Any subsequent annual installment payments shall be made prior to
February 28 of each calendar year thereafter until the Participant's EDP Account
balance is paid in full.

6.4  ELIGIBILITY REQUIREMENTS FOR SURVIVOR BENEFIT.  The obligation of the
     Company to pay the Survivor Benefit to any Beneficiary shall exist only if:

     a)  at the time of death, the Participant (i) was employed by the Company
         or was a director of the Company, (ii) was on an authorized leave of
         absence, or (iii) was absent from employment due to Disability, and, in
         each such case, had not yet begun receiving the Retirement Benefit; and

     b)  proof of death, in such form as reasonably deemed acceptable by the
         Committee, is furnished.


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Executive Deferral Plan (EDP)
Master Plan Document
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                                    Article 7
                               Termination Benefit

7.1  TERMINATION BENEFIT.  The Participant who for any reason experiences a
     Termination of Employment prior to his or her Retirement, death or
     Disability shall be entitled to a Termination Benefit in accordance with
     this Article.

7.2  PRIMARY ACCOUNT BALANCE.  The Participant terminating at any time shall be
     entitled to his or her Primary Account Balance.

7.3  SECONDARY ACCOUNT BALANCE.  The terminating Participant shall be entitled
     to the vested portion of his or her Secondary Account Balance in accordance
     with the vesting schedule contained below, which describes the vesting of
     the accrued interest on each annual Deferral Amount:

                                                  Vested Percentage of
                                                  Accrued Interest With
                                                  Respect to Each Annual
                                                  Deferral Amount in
     Date of Termination                          Secondary Account Balance
     -------------------                          -------------------------

     Prior to the beginning of
     the eighth Plan Year
     following the Plan Year in
     which an Annual Deferral
     Amount is Deferral                                    0%

     On or after the beginning
     of the eighth Plan Year
     following the Plan Year in
     which an Annual Deferral
     Amount is Deferred                                   100%

     Unvested Secondary Account Balances are forfeited at the date of
     Termination of Employment.

7.4  PAYMENT OF BENEFIT. Payment of the Primary Account Balance and the
     Secondary Account balance shall be made in a lump sum within ninety (90)
     days of the Participant's Termination of Employment.


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Executive Deferral Plan (EDP)
Master Plan Document
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                                    Article 8
                               Disability Benefit

8.1  AMOUNT OF DISABILITY BENEFIT.  In the case of the Disability of the
     Participant, the Committee may, at anytime during the Disability period and
     in its sole discretion, allow the Participant to discontinue deferrals and
     to continue to be eligible for benefits under Articles 4, 5, 6 or 7 (in
     accordance with those Articles), or terminate participation and receive a
     "Disability Benefit" in accordance with this Article 8. The amount of the
     Disability Benefit shall be equal to the Participant's existing EDP Account
     balance, as of the date the Committee makes a determination to terminate
     the Participant's participation in the Plan.  The Disability Benefit payout
     shall be at the discretion of the Committee, provided that such payout
     shall begin within ninety (90) days of such determination and shall not
     exceed 15 years in total.  The unpaid balance shall be credited with
     interest at the Standard Distribution Rate from the date of the
     determination through completion of payout.

                                     Article 9
                              Beneficiary Designation

9.1  BENEFICIARY DESIGNATION.  Each Participant shall have the right, at any
     time, to designate any person or persons as Beneficiary or Beneficiaries
     (both principal as well as contingent) to whom benefits under this Plan
     shall be paid in the event of the Participant's death prior to complete
     distribution of the benefits due under this Plan.

9.2  CHANGE OF BENEFICIARY DESIGNATION. Any Beneficiary designation may be
     changed by a Participant at any time by filing a new Beneficiary
     Designation Form with the Committee and shall become effective only when
     received, accepted and acknowledged by the Company in writing.  The filing
     and acceptance of a new Beneficiary Designation Form will cancel all
     Beneficiary Designations previously filed.  The Committee shall be entitled
     to rely on the last designation filed by the Participant prior to death.
     Despite the foregoing, if the Participant names someone other than his or
     her spouse as a Beneficiary, a spousal consent, in the form designated by
     the Committee, must be signed by that Participant's spouse and returned to
     the Committee.

9.3  NO PARTICIPANT DESIGNATION.  If a Participant fails to designate a
     Beneficiary as provided above, or if all designated Beneficiaries
     predecease the Participant, or die prior to complete distribution of the
     Participant's benefits, then the Participant's designated Beneficiary shall
     be deemed to be the surviving spouse.  If the Participant has no surviving
     spouse, the benefits remaining under the Plan shall be payable to the
     Participant's estate.

9.4  EFFECT OF PAYMENT.  The payment of benefits under the Plan to the deemed
     Beneficiary shall completely discharge the Company's obligations under
     this Plan.


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Executive Deferral Plan (EDP)
Master Plan Document
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                                    Article 10
                    Plan Termination, Amendment or Modification

10.1 PLAN TERMINATION.  The Company reserves the right to terminate the Plan at
     any time. Upon termination of the Plan, the Participants' then existing EDP
     Accounts, including interest earned through the date of such termination,
     shall be paid out as if each Participant Retired on the date of
     termination.  Prior to a Change in Control, the Company reserves the right,
     at its sole discretion and notwithstanding any elections made by the
     Participant, to pay such benefits in a lump sum or in annual installments
     for up to 15 years, with interest credited on the unpaid balance using the
     Preferred Distribution Rate.  The termination of the Plan shall not
     adversely affect any Participant or Beneficiary who has become entitled to
     the payment of any benefits under the Plan as of the date of termination;
     provided, however, that the Company shall have the right to pay any
     remaining EDP Account balance in a lump sum.

10.2 AMENDMENT OR MODIFICATION.  The Company may, at any time, amend or modify
     the Plan in whole or in part, provided, however, that no amendment or
     modification shall be effective to decrease or restrict any EDP Account
     balance, calculated as if the Participant experienced a Termination of
     Employment as of the effective date of the amendment or modification, or if
     the Participant was eligible to Retire, the Participant had Retired as of
     the effective date of the amendment or modification.  The amendment or
     modification of the Plan shall not affect any Participant or Beneficiary
     who has become entitled to the payment of benefits under the Plan as of the
     date of the amendment or modification, provided that the Committee has the
     right to make a lump sum payment of all remaining balances.

10.3 CHANGE IN CONTROL.  If a Change in Control occurs, a Participant shall
     immediately become vested in his or her Secondary Account Balance.  If the
     Change of Control is due to the exercise of the Purchase Option by ALZA and
     the Participant becomes an employee of ALZA in connection with the Change
     of Control, then the Participant will no be deemed to have "Retired" or to
     have a "Termination of Employment" from the Company for purposes of this
     Plan, and this Plan will continue, with respect to such Participant, as an
     ALZA plan, subject to the approval of ALZA's Board of Directors.  If (i)
     the Participant does not become an ALZA employee upon such Change of
     Control or (ii) the ALZA Board of Director does not approve the
     continuation of this Plan as an ALZA plan, then the Participant's EDP
     Account shall be paid to the Participant in three equal annual
     installments, the first within sixty days of the decision of the ALZA Board
     of Directors, or the last day of employment with the Company, whichever is
     applicable.  Interest shall accrue at the Preferred Rate on all unpaid
     amounts.

10.4 EFFECT OF PAYMENT.  The full payment of the applicable benefit under
     Articles 5, 6, 7 or 8 of the Plan shall completely discharge all
     obligations to a Participant and his or her Beneficiaries under this Plan
     and the Participant's Plan Agreement shall terminate.

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Executive Deferral Plan (EDP)
Master Plan Document
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                                    Article 11
                                      Trust

11.1 ESTABLISHMENT OF THE TRUST; PREMIUM.  The Company may establish, in its
     sole discretion, the Trust and, if so established, shall at least annually
     transfer over to the Trust such assets as the Committee determines, in its
     sole discretion, are necessary to provide for some or all of the Company's
     future liabilities under the Plan.

11.2 INTERRELATIONSHIP OF THE PLAN AND THE TRUST.  The provisions of the Plan
     and each Plan Agreement shall govern the rights of a Participant to receive
     distributions pursuant to the Plan.  The provisions of the Trust, if the
     Trust is established, shall govern the rights of the Company, a
     Participant, a Participants' Beneficiary and the Company's creditors as to
     the assets of the Trust.  The Company shall at all times remain liable to
     carry out its obligations under the Plan.  The Company's obligations under
     the Plan may be satisfied with Trust assets distributed pursuant to the
     terms of the Trust.

                                     Article 12
                                 Claims Procedures

12.1 PRESENTATION OF CLAIM.  Any Participant or Beneficiary of a deceased
     Participant (such Participant or Beneficiary being referred to below as a
     "Claimant") may deliver to the Committee a written claim for a
     determination with respect to the amounts distributable to such Claimant
     from the Plan.  If such a claim relates to the contents of a notice
     received by the Claimant, the claim must be made within 60 days after such
     notice was received by the Claimant.  All other claims must be made within
     180 days of the date on which the event that caused the claim to arise
     occurred.  The claim must state with particularity the determination
     desired by the Claimant.

12.2 NOTIFICATION OF DECISION.  The Committee shall consider a Claimant's claim
     within 60 days of receipt of that claim, and shall notify the Claimant in
     writing:

     a)  that the Claimant's requested determination has been made, and that
         the claim has been allowed in full; or that the Committee has reached a
         conclusion contrary, in whole or in part, to the Claimant's requested
         determination, and such notice must set forth in a manner calculated to
         be understood by the Claimant:

            (i)   the specific reason(s) for the denial of the claim, or any
                  part of it;

            (ii)  the specific reference(s) to pertinent provisions of the Plan
                  upon which such denial was based;

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Master Plan Document
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            (iii) a description of any additional material or information
                  necessary for the Claimant to perfect the claim, and an
                  explanation of why such material or information is necessary;
                  and

            (iv)  an explanation of the claim review procedure set forth in
                  Section 12.3 below.

12.3 REVIEW OF A DENIED CLAIM.  Within 60 days after receiving a notice from the
     Committee that a claim has been denied, in whole or in part, a Claimant (or
     the Claimant's duly authorized representative) may file with the Committee
     a written request for a review of the denial of the claim.  Thereafter, but
     not later than 30 days after the review procedure began, the Claimant (or
     the Claimant's duly authorized representative):

     c)  may review pertinent documents;

     d)  may submit written comments or other documents; and/or

     e)  may request a hearing, which the Committee, in its sole discretion,
         may grant.

12.4 DECISION ON REVIEW.  The Committee shall render its decision on review
     promptly, and not later than 60 days after the filing of a written request
     for review of the denial, unless a hearing is held or other special
     circumstances require additional time, in which case the Committee's
     decision must be rendered within 120 days after such date.  Such decision
     must be written in a manner calculated to be understood by the Claimant,
     and it must contain:

     d)  specific reasons for the decision;

     e)  specific reference(s) to the pertinent Plan provisions upon which the
         decision was based; and

     f)  such other matters as the Committee deems relevant.

12.5 LEGAL ACTION.  A Claimant's compliance with the foregoing provisions
     of this Article 12 is a mandatory prerequisite to a Claimant's right to
     commence any legal action with respect to any claim for benefits under
     this Plan.


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Executive Deferral Plan (EDP)
Master Plan Document
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                                   Article 13
                                 Miscellaneous

13.1 UNSECURED GENERAL CREDITOR.  Participants and their Beneficiaries, heirs
     and successors shall have the status of general unsecured creditors of the
     Company, and the Plan constitutes a mere promise by the Company to make
     benefit payments in the future.

13.2 NONASSIGNABILITY.  Neither a Participant nor any other person shall have
     any right to commute, sell, assign, transfer, pledge, anticipate, mortgage
     or otherwise encumber, transfer, hypothecate, alienate, or convey in
     advance of actual receipt, the amounts, if any, payable hereunder, or any
     part thereof, which are, and all rights to which are, expressly declared to
     be unassignable and non-transferable.  No part of the amounts payable
     shall, prior to actual payment, be subject to seizure, attachment,
     garnishment or sequestration for the payment of any debts, judgments,
     alimony or separate maintenance owed by a Participant or any other person,
     nor be transferable by operation of law in the event of a Participant's or
     any other person's bankruptcy or insolvency.

13.3 NOT A CONTRACT OF EMPLOYMENT.  The terms and conditions of this Plan shall
     not be deemed to constitute a contract of employment between the Company
     and the Participant, and the Participant (or Beneficiary) shall have no
     rights against the Company except as may otherwise be specifically provided
     herein.  Such employment is acknowledged to be an "at will" employment
     relationship that can be terminated at any time for any reason, with or
     without cause, unless expressly provided in a written employment agreement.
     Moreover, nothing in this Plan shall be deemed to give a Participant the
     right to be retained in the service of the Company or to interfere with the
     right of the Company to discipline or discharge him at any time.

13.4 PROTECTIVE PROVISIONS.  A Participant will cooperate with the Company by
     furnishing any and all information requested by the Company in order to
     facilitate the payment of benefits hereunder, and by taking such physical
     examinations as the Company may deem necessary, and taking such other
     action as may be requested by the Company.

13.5 TERMS. Whenever any words are used herein in the masculine, they shall be
     construed as though they were used in the feminine in all cases where they
     would so apply; and wherever any words are used herein in the singular or
     in the plural, they shall be construed as though they were used in the
     plural or in the singular, as the case may be, in all cases where they
     would so apply.

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Master Plan Document
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13.6  CAPTIONS.  The captions of the articles, sections and paragraphs of this
      Plan are for convenience only and shall not control or affect the meaning
      or construction of any of its provisions.

13.7  GOVERNING LAW.  The provisions of this Plan shall be construed and
      interpreted according to the laws of the State of California.

13.8  VALIDITY.  In case any provision of this Plan shall be illegal or invalid
      for any reason, said illegality or invalidity shall not affect the
      remaining parts hereof, but this Plan shall be construed and enforced as
      if such illegal and invalid provision had never been inserted herein.

13.9  NOTICE.  Any notice or filing required or permitted to be given to the
      Committee under this Plan shall be sufficient if in writing and
      hand-delivered, or sent by registered or certified mail or facsimile
      transmission, to:

                       Therapeutic Discovery Corporation
                       Executive Deferral Plan Committee
                                1375 California
                                P.O. Box 10051
                           Palo Alto, CA 94303-0806

      Such notice shall be deemed given as of the date of delivery or, if
      delivery is made by mail, as of the date shown on the postmark on the
      receipt for registration or certification.

13.10 SUCCESSORS.  The provisions of this Plan shall bind and inure to the
      benefit of the Company and its successors and assigns.  The term
      successors as used herein shall include any corporate or other business
      entity which shall, whether by merger, consolidation, purchase or
      otherwise, acquire all, or substantially all, of the business and assets
      of the Company, and successors or any such corporation or other business
      entity.

13.11 SPOUSE'S INTEREST. Interest in the benefits hereunder of a spouse of a
      Participant who has predeceased the Participant shall automatically pass
      to the Participant and shall not be transferable by such spouse in any
      manner, including but not limited to such spouse's will, nor shall such
      interest pass under the laws of intestate succession.


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Master Plan Document
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13.12 DISTRIBUTION IN THE EVENT OF TAXATION.  If, for any reason, all or any
      portion of a Participant's benefit under this Plan becomes taxable to the
      Participant prior to receipt, a Participant may petition the Committee for
      a distribution of assets sufficient to meet the Participant's tax
      liability (including additions to tax, penalties and interest).  Upon the
      grant of such a petition, which grant shall not be unreasonably withheld,
      the Company shall distribute to the Participant funds in an amount equal
      to that Participant's federal, state and local tax liability associated
      with such taxation (which amount shall not exceed a Participant's accrued
      benefit under the Plan), which liability shall be measured by using that
      Participant's then current highest federal, state and local marginal tax
      rate, plus the rates or amounts for the applicable additions to tax,
      penalties and interest.  If the petition is granted, the tax liability
      distribution shall be made within 90 days of the date when the
      Participant's petition is granted.  Such a distribution shall affect and
      reduce the benefits to be paid under this Plan.

13.13 INCOMPETENT.  In the event that it shall be found upon evidence
      satisfactory to the Committee that any Participant or Beneficiary to whom
      a benefit is payable under this Plan is unable to care for his or her
      affairs because of illness or accident, any payment due (unless prior
      claim had been made by a duly authorized guardian or other legal
      representative) may be paid, upon appropriate indemnification of the
      Committee, to the spouse of such person or any other person deemed by the
      Committee to have incurred expense for such Participant. Any such payment
      shall be a payment out of the account of the Participant and shall be a
      complete discharge of any liability of the Plan for such payment amount.

                                        Article 14
                                      Administration

14.1  COMMITTEE DUTIES.  This Plan shall be administered by the Committee.  The
      Committee shall also have the authority to make, amend, interpret, and
      enforce all appropriate rules and regulations for the administration of
      this Plan and decide or resolve any and all questions including
      interpretations of this Plan, as may arise in connection with the Plan.

14.2  AGENTS.  In the administration of this Plan, the Committee may, from time
      to time, employ agents and delegate to them such administrative duties as
      it sees fit and may from time to time consult with counsel who may be
      counsel to the Company.


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Master Plan Document
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14.3 BINDING EFFECT OF DECISIONS.  The decision or action of the Committee with
     respect to any question arising out of or in connection with the
     administration, interpretation, and application of the Plan, and the rules
     and regulations promulgated hereunder, shall be final and conclusive, and
     binding upon all persons having any interest in the Plan.

14.4 INDEMNITY OF COMMITTEE.  The Company shall indemnify and hold harmless the
     members of the Committee against any and all claims, loss, damage, expense
     or liability arising from any action or failure to act with respect to
     this Plan, except in the case of willful misconduct by the Committee or
     any of its members.

14.5 COMPANY INFORMATION.  To enable the Committee to perform its functions, the
     Company shall supply full and timely information to the Committee on all
     matters relating to the salary of all Participants, the date and
     circumstances of the retirement disability, death, or termination of
     employment of all Participants, and such other pertinent information as the
     Committee may reasonably require.

14.6 CHANGE IN PAYMENTS.  The Committee shall have the power, at its sole
     discretion, to change the manner and timing of payments to be made to a
     Participant or Beneficiary from that which would be otherwise payable.



IN WITNESS WHEREOF the Company has signed this Master Plan Document

this_____day of________________,1996.


Company:                                     Therapeutic Discovery Corporation,
                                             a Delaware corporation

                                             By: /s/ Gary L. Neil
                                                --------------------------------
                                             Its: President
                                                 -------------------------------

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