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                                                                 EXHIBIT 10.33



                                      RULES

                                     OF THE

                         MILLENNIUM PHARMACEUTICALS, INC

                                    SAYE PLAN









                (Established by the Company on 21 September 2001
                       and approved by the Inland Revenue
                         under Schedule 9 to the Income
                         and Corporation Taxes Act 1988
                              on October 16, 2001]
                              under ref SRS 2690 )




                                ERNST & YOUNG LLP
                                   ROLLS HOUSE
                                 ROLLS BUILDINGS
                                   FETTER LANE
                                 LONDON EC4A 1NH
                               TEL: 020 7951 2000
                               FAX: 020 7951 4001

                          FINAL VERSION - OCTOBER 2001



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                                    CONTENTS

RULE

1.  Definitions and interpretation

2.  Invitations to apply for Options

3.  Scaling down

4.  Grant of Options

5.  Plan limits

6.  Rights of exercise and lapse of Options

7.  Exercise of Options

8.  Takeovers and liquidations

9.  Exchange of Options on a takeover

10. Variation of share capital

11. Administration

12. Amendments

13. General



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                         MILLENNIUM PHARMACEUTICALS, INC

                                    SAYE PLAN



1.   DEFINITIONS AND INTERPRETATION

     In this Plan, the following words and expressions shall, where the context
     so permits, have the following meanings:

     "ASSOCIATED COMPANY"          has the meaning that the expression bears in
                                   Paragraph 23 of Schedule 9 by virtue of
                                   section 187(2) of the Taxes Act;

     "AUDITORS"                    means the auditors for the time being of the
                                   Company;

     "BONUS"                       means any sum payable by way of terminal
                                   bonus under a Savings Contract being the
                                   additional payment made by the nominated
                                   Savings Authority when repaying contributions
                                   under a Savings Contract;

     "BONUS                        DATE" means the earliest date on which the
                                   relevant Bonus is payable;

     "COMMITTEE"                   means the Board of Directors for the time
                                   being of the Company or a committee thereof
                                   duly designated for the administration of
                                   this Plan (or any person authorised by that
                                   committee);

     "THE COMPANY"                 means Millennium Pharmaceuticals, Inc whose
                                   principal office is at 75 Sidney Street,
                                   Cambridge, Massachusetts, 02139, USA;

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     "CONTROL"                     has the meaning given by section 840 of the
                                   Taxes Act;


     "DATE-OF-GRANT"               means the date on which an Option is granted;

     "ELIGIBLE-EMPLOYEE"           means:

                                   (a)  any person who is a director required to
                                        devote to his duties not less than 25
                                        hours per week (excluding meal breaks),
                                        or any employee (other than one who is a
                                        director), of any Participating Company
                                        who:

                                        (i)  has such qualifying period (if any)
                                             of continuous service (being a
                                             period commencing not earlier than
                                             five years prior to the Date of
                                             Grant) as the Committee may in its
                                             absolute discretion and from time
                                             to time determine; and

                                        (ii) is chargeable to tax in respect of
                                             his office or employment under Case
                                             I of Schedule E; and

                                   (b)  any other director or employee of any
                                        Participating Company whom the Committee
                                        may in their absolute discretion and
                                        from time to time select,

                                   who is not precluded from participating in
                                   this Plan by paragraph 8 of Schedule 9
                                   (material interest in a close company within
                                   the preceding 12 months);


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     "EXERCISE PRICE"              means the price (in Pounds Sterling) at which
                                   each share of Stock subject to an Option may
                                   be acquired on the exercise of that Option,
                                   being (subject to Rule 10) not manifestly
                                   less than eighty five per cent (85%) of the
                                   Market Value of a share of Stock (or such
                                   other percentage as shall from time to time
                                   be specified in paragraph 25 of Schedule 9)
                                   on the business day preceding the day on
                                   which invitations are issued;

     "GMT"                         means Greenwich Mean Time;

     "GROUP COMPANY"               means the Company, any company under the
                                   Control of the Company, and any other
                                   Associated Company;

     "MARKET VALUE"                means on any day:

                                   (a)  if the Stock is listed on the New York
                                        Stock Exchange, the closing price of the
                                        Stock on that exchange; or

                                   (b)  if the Stock is not listed on the New
                                        York Stock Exchange, the market value as
                                        determined in accordance with Part VIII
                                        of the Taxation of Chargeable Gains Act
                                        1992 and agreed in advance with the
                                        Inland Revenue Shares Valuation
                                        Division;


                                                                               4

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                                        converted into Pounds Sterling using the
                                        prevailing exchange rate on that date as
                                        determined from the Wall Street Journal,
                                        or such other source as the Committee
                                        may in its absolute discretion and from
                                        time to time determine, or any other
                                        exchange rate as shall be agreed with
                                        the Inland Revenue prior to the Date of
                                        Grant.

     "MAXIMUM-CONTRIBUTION"        means the maximum aggregate Monthly
                                   Contribution which a Participant may make
                                   under all Savings Contracts linked to options
                                   granted to him under this Plan or any other
                                   savings-related share option plan approved by
                                   the Inland Revenue under Schedule 9, being
                                   the lesser of:

                                   (a)  (pound)250 per month (or such other
                                        maximum amount as shall be specified in
                                        paragraph 24(2)(a) of Schedule 9); and

                                   (b)  such other maximum contribution as may
                                        be determined from time to time by the
                                        Committee which need not be the same in
                                        relation to all Eligible Employees
                                        provided that it does not infringe the
                                        requirements of paragraphs 26(1) and (2)
                                        of Schedule 9 (participation on similar
                                        terms);

     "MONTHLY CONTRIBUTION"        means the monthly contribution agreed to be
                                   paid by an Optionholder under his Savings
                                   Contract;

     "OPTION"                      means a right to acquire Stock pursuant to
                                   this Plan;

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     "OPTION HOLDER"               means an Eligible Employee to whom an Option
                                   has been granted under this Plan;

     "PARTICIPATING COMPANY"       means the Company and any company of which
                                   the Company has Control but excluding any
                                   company which is for the time being specified
                                   by the Committee as not being a Participating
                                   Company;

     "THIS PLAN"                   means the Millennium Pharmaceuticals, Inc
                                   SAYE Plan, as amended from time to time;

     "SAVINGS AUTHORITY"           means the building society or bank recognised
                                   by the Committee from time to time for the
                                   purpose of receiving Monthly Contributions
                                   under Savings Contracts;

     "SAVINGS CONTRACT"            means a contract under a certified
                                   contractual savings scheme (within the
                                   meaning of section 326 of the Taxes Act)
                                   approved by the Inland Revenue for the
                                   purpose of Schedule 9;

     "SCHEDULE 9"                  means Schedule 9 to the Taxes Act;

     "SPECIFIED AGE"               means the age of 60;

     "STOCK"                       means the common stock of the Company which
                                   satisfies the requirements of paragraphs 10
                                   to 14 of Schedule 9;

     "TAXES ACT"                   means the Income and Corporation Taxes Act
                                   1988.

     References to any statutory provision are to that provision as amended or
     re-enacted from time to time, and, unless the context otherwise requires,
     words in the singular shall include the plural and vice versa and words
     importing the masculine shall include the feminine and vice versa.


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<PAGE>


2. INVITATIONS TO APPLY FOR OPTIONS

     2.1  The Committee may invite all Eligible Employees to apply for the grant
          of Options on such dates as it may from time to time resolve after the
          approval of this Plan or any amendment hereto by the Inland Revenue
          under Schedule 9.

     2.2  Such invitations shall be made to all Eligible Employees and shall
          include details of the following matters which shall be determined by
          the Committee:

          (a)  the Exercise Price or the means by which it will be notified to
               Eligible Employees;

          (b)  the latest date by which applications must be received, being
               neither earlier than 14 days nor later than 28 days after the
               date of the invitations; and

          (c)  the Maximum Contribution.

     2.3  Each invitation shall be accompanied by:

          (a)  a proposal form for a Savings Contract; and

          (b)  an application form.

     2.4  An application form shall be in such form as the Committee may from
          time to time prescribe (subject to the prior approval of the Inland
          Revenue) save that it must provide for the applicant to state:

          (a)  the Monthly Contribution (being a multiple of(pound)1 and not
               less than(pound)5) which he wishes to make under the related
               Savings Contract; and


                                                                               7

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          (b)  that his proposed Monthly Contribution (when taken together with
               any Monthly Contribution he makes under any other Savings
               Contract linked to an Option granted to him under this Plan or
               any other savings-related share option plan approved by the
               Inland Revenue under Schedule 9) will not exceed (pound)250 per
               month (or such other maximum amount as shall be specified in
               paragraph 24(2)(a) of Schedule 9).

     2.5  Each application shall provide that, in the event of scaling down in
          accordance with Rule 3, the Committee is authorised by the applicant
          to modify his application to reflect such scaling down.

     2.6  Each application shall be deemed to be for an Option over such number
          of shares of Stock as can be acquired at the Exercise Price with the
          expected repayment under the related Savings Contract at the Bonus
          Date.


3. SCALING DOWN

     3.1  To the extent that valid applications are received in excess of any
          maximum number of shares of Stock which may be determined by the
          Committee pursuant to Rule 5, the Committee shall scale down
          applications in the same manner in order to eliminate the excess by:

          (a)  imposing a lower Maximum Contribution in respect of the offer;
               and/or

          (b)  reducing pro-rata the proposed Monthly Contributions in excess
               of(pound)5; and

          (c)  so far as necessary, selecting by lot.

     3.2  Where applications are scaled down in accordance with Rule 3.1 all
          relevant applications shall be deemed to have been amended or
          withdrawn, as the case may be.

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<PAGE>

4. GRANT OF OPTIONS

     4.1  Options shall be granted as soon as the Committee deems practicable
          following the date stated on the relevant invitation as being the date
          of its expiry in accordance with Rule 2.2 (b) provided that the Date
          of Grant shall not in any circumstances be more than 30 days (or 42
          days in the event that applications are scaled down under Rule 3)
          after the day by reference to which the Exercise Price was fixed.

     4.2  No Option shall be granted to a person unless at the Date of Grant he
          is an Eligible Employee.

     4.3  As soon as is practicable after having granted an Option to an
          Eligible Employee the Committee shall issue to him, or procure the
          issue to him of, an option certificate. The option certificate shall
          be in such form determined by the Committee from time to time (subject
          to it being acceptable to the Inland Revenue) and shall state:

          (a)  the Date of Grant of the Option;

          (b)  the number and class of Stock over which the Option is granted;
               and

          (c)  the Exercise Price payable for each share of Stock subject to the
               Option.

     4.4  Subject to the right of an Optionholder's personal representatives to
          exercise an Option as provided in Rule 6.4, every Option shall be
          personal to the Eligible Employee to whom it is granted and shall not
          be capable of being transferred, assigned or charged.

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<PAGE>

5. PLAN LIMITS

     In respect of each grant of Options under the Plan, the Committee may in
     its discretion place a limit on the number of shares of Stock to be made
     available under this Plan on that occasion.

6. RIGHTS OF EXERCISE AND LAPSE OF OPTIONS

     6.1  Save as provided in Rules 6.4 (death), 6.5 (good leavers), 6.8
          (reaching the Specified Age) and 8 (takeovers etc), an Option may be
          exercised only during the six-month period commencing with the Bonus
          Date under the related Savings Contract.

     6.2  Save as provided in Rules 6.4, 6.5 and 6.6, an Optionholder may only
          exercise an Option while he is a director or employee of a Group
          Company.

     6.3  No Option may be exercised by an Optionholder at any time when he is,
          or by the personal representatives of an Optionholder who at the date
          of his death was, prohibited from such exercise by virtue of the
          provisions of paragraph 8 of Schedule 9 (material interest in a close
          company within the preceding 12 months).

     6.4  Subject to Rule 6.3, an Option may be exercised by the personal
          representatives of a deceased Optionholder:

          (a)  during the period of one year following the date of the
               Optionholder's death if such death occurs before the Bonus Date;
               or

          (b)  during the period of one year following the Bonus Date if the
               Optionholder's death occurs within the period of six months after
               the Bonus Date.


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<PAGE>


     6.5  Subject to Rule 6.6, if an Optionholder ceases to hold any office or
          employment with a Participating Company on account of:

          (a)  injury or disability (evidenced to the satisfaction of the
               Committee); or

          (b)  redundancy (within the meaning of the Employment Rights Act
               1996); or

          (c)  retirement on reaching the Specified Age or any other age at
               which he is bound to retire in accordance with the terms of his
               contract of employment; or

          (d)  the transfer of the undertaking or part-undertaking in which the
               Optionholder is employed to a person other than a Group Company;
               or

          (e)  the Company by which the Optionholder is employed ceasing to be
               under the Control of the Company

               the Option may be exercised by five o'clock in the afternoon
               (5.00pm) GMT on the day the period of six months after the date
               of such cessation expires.

     6.6  An Optionholder shall not be treated as having ceased to hold any
          office or employment with a Participating Company for the purposes of
          this Rule 6 if he continues to hold any office or employment with a
          Group Company.

     6.7  An Option shall lapse on the occurrence of the earliest of the
          following:

          (a)  subject to Rule 6.7(b) below, at five o'clock in the afternoon
               (5.00pm) GMT on the day the period of six months after the Bonus
               Date expires; or

          (b)  at five o'clock in the afternoon (5.00pm) GMT on the day any of
               the applicable periods specified in Rules 6.4 (exercise by
               personal representatives) and 6.5 (good leavers) expire but if an
               Optionholder dies

                                                                              11

<PAGE>

               while time is running under Rule 6.5, the Option shall not lapse
               until five o'clock in the afternoon (5.00pm) GMT on the day the
               relevant period in Rule 6.4(a) or (b) expires;

          (c)  subject to Rule 9 (exchange of options on a takeover), at five
               o'clock in the afternoon (5.00pm) GMT on the day the applicable
               periods in Rules 8.1, 8.2, 8.3 and 8.4 (takeovers etc) expire;

          (d)  subject to Rule 6.6 (retaining an office or employment with an
               associated company etc), at five o'clock in the afternoon
               (5.00pm) GMT on the day on which an Optionholder ceases to be a
               director or employee of a Participating Company for any reason
               other than his death or those specified in Rule 6.5 (good
               leavers); and

          (e)  at five o'clock in the afternoon (5.00pm) GMT on the day on which
               the Optionholder becomes bankrupt or does or omits to do anything
               as a result of which he is deprived of the legal or beneficial
               ownership of the Option.

     6.8  If an Optionholder continues to be employed by a Participating Company
          after the date on which he reaches the Specified Age, he may exercise
          an Option by five o'clock in the afternoon (5.00pm) GMT on the day on
          which the period of six months following that date expires.

     7. EXERCISE OF OPTIONS

     7.1  An Option may only be exercised with monies not exceeding the amount
          of repayment (including any Bonus or interest) made under the related
          Savings Contract. For this purpose, repayment under the Savings
          Contract shall exclude the repayment of any Monthly Contribution the
          due date for payment of which falls more than one month after the date
          on which repayment is made.


                                                                              12

<PAGE>


     7.2  Save as otherwise provided in this Plan, an Option shall be
          exercisable in whole or in part by notice in writing (in the form
          prescribed by the Committee) given by the Optionholder (or his
          personal representatives) to the Company. If exercised in part, the
          Option shall lapse as to the unexercised part. The notice of exercise
          of the Option shall be accompanied by the relevant Option Certificate
          and either a remittance in cleared funds for the aggregate of the
          Exercise Prices payable or authority for the Savings Authority to pay
          such amount to the Company.

     7.3  Within 30 days after the Option Exercise the Committee shall allot or
          procure the transfer of the Stock in respect of which the Option has
          been validly exercised and shall issue a definitive certificate in
          respect of the Stock allotted or transferred unless the Committee
          considers that such allotment or transfer would not be lawful or
          appropriate in the relevant jurisdiction.

     7.4  Stock allotted under this Plan shall rank pari passu in all respects
          with the shares of Stock of the same class for the time being in issue
          save as regards any rights attaching to such Stock by reference to a
          record date prior to the date of allotment and, in the case of a
          transfer of existing Stock, the transferee shall not acquire any
          rights attaching to such Stock by reference to a record date prior to
          the date of such transfer.

     7.5  If and so long as the Stock is traded on NASDAQ or listed on any other
          stock exchange, the Company shall apply, or procure the application,
          for the formal admittance of any Stock allotted under this Plan to
          NASDAQ or to that other exchange.

     8. TAKEOVERS AND LIQUIDATIONS

     8.1  If any person obtains Control of the Company as a result of making:

                                                                              13

<PAGE>



          (a)  a general offer to acquire the whole of the issued ordinary share
               capital of the Company which is made on a condition such that if
               it is satisfied the person making the offer will have Control of
               the Company; or

          (b)  a general offer to acquire all the stock in the Company which is
               of the same class as the Stock,

               any Option may be exercised immediately before and conditionally
               upon such change of Control or by five o'clock in the afternoon
               (5.00pm) GMT on the day the period of six months after that date
               expires. For the purposes of this Rule 8.1 a person shall be
               deemed to have obtained Control of the Company if he and others
               acting in concert with him have together obtained Control of it.

     8.2  If, under section 425 of the Companies Act 1985 (or closely comparable
          overseas legislation acceptable to the Inland Revenue), the Court
          sanctions a compromise or arrangement proposed for the purposes of or
          in connection with a scheme for the reconstruction of the Company or
          its amalgamation with any other company or companies, any Option may
          be exercised immediately prior to and conditionally upon the Court
          sanctioning such compromise or arrangement or by five o'clock in the
          afternoon (5.00pm) GMT on the day the period of six months after the
          date of such compromise or arrangement expires.

     8.3  If any person becomes bound or entitled to acquire stock in the
          Company under sections 428 to 430 of the Companies Act 1985 (or
          closely comparable overseas legislation acceptable to the Inland
          Revenue) any subsisting Option may be exercised at any time when that
          person remains so bound or entitled.

     8.4  If the Company passes a resolution for voluntary winding up, any
          Option may be exercised by five o'clock in the afternoon (5.00pm) GMT
          on the day the period of six months after the passing of the
          resolution expires.

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     8.5  Notwithstanding any other provisions of this Plan, if at Bonus Date
          the Optionholder holds an office or employment in a company which is
          not a Participating Company but which is a company under the Control
          of the Company or an Associated Company, he may exercise his option by
          five o'clock in the afternoon (5.00pm) GMT on the day the period of 6
          months after the Bonus Date expires.

9. EXCHANGE OF OPTIONS ON A TAKEOVER

     9.1  Notwithstanding the provisions of Rule 8, if any company ("the
          Acquiring Company") obtains Control of the Company or becomes bound or
          entitled to acquire stock in the Company within any of the sets of
          circumstances specified in Rules 8.1, 8.2 and 8.3, any Optionholder
          may at any time within the periods specified in those Rules, by
          agreement with the Acquiring Company, release his Option ("the Old
          Option") in consideration of the grant to him of a new option ("the
          New Option") which is equivalent to the Old Option (by virtue of
          satisfying the requirements of paragraph 15(3) of Schedule 9) but
          relates to shares in a different company (whether the Acquiring
          Company itself or some other company falling within paragraph (b) or
          (c) of paragraph 10 of Schedule 9).

     9.2  Where any New Options are granted pursuant to Rule 9.1 they shall be
          regarded for the purposes of the subsequent application of the
          provisions of this Plan as having been granted at the time when the
          corresponding Old Options were granted and, with effect from the date
          on which the New Options are granted:

          (a)  save for the definitions of "Participating Company" and "Group
               Company" in Rule 1, references to "the Company" (including the
               definition in Rule 1) shall be construed as being references to
               the

                                                                              15

<PAGE>


               Acquiring Company or such other company to whose stock the New
               Option relate; and

          (b)  references to "Stock" (including the definition in Rule 1) shall
               be construed as being references to shares in the Acquiring
               Company or shares in such other company to which the New Options
               relate.

10. VARIATION OF SHARE CAPITAL

     10.1 In the event of any capitalisation issue, rights issue, consolidation,
          subdivision, reduction or other variation of the share capital of the
          Company:

          (a)  the number of shares of Stock comprised in an Option;

          (b)  their Exercise Price;

          (c)  where an Option has been exercised but no Stock has been allotted
               or transferred in satisfaction of such exercise, the number of
               shares of Stock to be so allotted or transferred and their
               Exercise Price;

               may, subject to the prior approval of the Inland Revenue, be
               varied in such manner as the Committee shall determine and (save
               in the event of a capitalisation) the Auditors (acting as experts
               and not arbitrators) shall confirm in writing to be in their
               opinion fair and reasonable.

     10.2 The Committee may take such steps as they consider necessary to notify
          Optionholders of any adjustment made under this Rule 10 and to call
          in, cancel, endorse, issue or re-issue any option certificate
          consequent upon such adjustment.


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<PAGE>



11. ADMINISTRATION

     11.1 The Committee shall have power from time to time to make and vary such
          regulations (not being inconsistent with this Plan) for the
          implementation and administration of this Plan as they think fit.

     11.2 The decision of the Committee shall be final and binding in all
          matters relating to this Plan (other than in the case of matters to be
          determined or confirmed by the Auditors in accordance with this Plan).

     11.3 The costs of establishing and administering this Plan shall be borne
          by the Company.

     11.4 The Company may, but shall not be obliged to, provide Eligible
          Employees or Optionholders with copies of any notices circulars or
          other documents sent to shareholders of the Company.

12. AMENDMENTS

     12.1 Prior to approval of this Plan by the Inland Revenue under Schedule 9
          the Committee may alter the Rules of this Plan as may be necessary to
          obtain such approval.

     12.2 After the date on which this Plan is approved by the Inland Revenue
          under Schedule 9, the Rules may be amended in any respect by
          resolution of the Committee provided that no amendment shall take
          effect which would cause this Plan (or any or all of the Options
          granted under it) to cease to be approved by the Inland Revenue and no
          amendment shall have effect until it has been approved by the Inland
          Revenue.

     12.3 Written notice of any amendment to this Plan shall be given to all
          Optionholders affected thereby.

                                                                              17

<PAGE>



13. GENERAL

     13.1 This Plan shall commence upon the date of its approval by the Inland
          Revenue and shall (unless previously terminated by a resolution of the
          Committee or a resolution of the Company in General Meeting) terminate
          at five o'clock in the afternoon (5.00pm) GMT on the day the period of
          ten years from such date expires. On termination no further Options
          may be granted but such termination shall be without prejudice to any
          accrued rights in existence at the date thereof.

     13.2 The Company will at all times keep available sufficient authorised and
          unissued Stock, or shall ensure that sufficient Stock will be
          available (whether as treasury Stock or otherwise), to satisfy the
          exercise to the full extent still possible of all subsisting Options,
          taking account of any other obligations of the Company to issue Stock.

     13.3 Notwithstanding any other provision of this Plan:

          (a)  this Plan shall not form part of any contract of employment
               between any Participating Company and any employee of any such
               company and the rights and obligations of any individual under
               the terms of his office or employment with any Group Company
               shall not be affected by his participation in this Plan or any
               right which he may have to participate in it and this Plan shall
               afford such an individual no additional rights to compensation or
               damages in consequence of the termination of such office or
               employment for any reason whatsoever;

          (b)  no Optionholder shall be entitled to any compensation or damages
               for any loss or potential loss which he may suffer by reason of
               being unable to exercise an Option in consequence of the loss or
               termination of his office or employment with any Group Company
               for any reason whatsoever;

                                                                              18

<PAGE>


          (c)  this Plan shall not confer on any person any legal or equitable
               rights (other than those constituting the Options themselves)
               against any Group Company directly or indirectly, or give rise to
               any cause of action at law or in equity against any Group
               Company.

     13.4 Save as otherwise provided in this Plan any notice or communication to
          be given by the Company to any Eligible Employee or Optionholder may
          be:

          (a)  delivered by electronic mail bearing the Eligible Employee's or
               Optionholder's electronic signature and it shall be deemed to
               have been received upon electronic confirmation of such delivery;
               or

          (b)  personally delivered or sent by ordinary post to his last known
               address and where a notice or communication is sent by post it
               shall be deemed to have been received 48 hours after the same was
               put into the post properly addressed and stamped.

               Stock certificates and other communications sent by post will be
               sent at the risk of the Eligible Employee or Optionholder
               concerned and the Company shall have no liability whatsoever to
               any such person in respect of any notification, document, stock
               certificate or other communication so given, sent or made.

     13.5 Any notice to be given to the Company shall be delivered or sent to
          the Company at its registered office and shall be effective upon
          receipt.

     13.6 This Plan and all Options granted under it shall be governed by and
          construed in accordance with English law.


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