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                                                                  Exhibit 10.1.1

                                 METABOLIX, INC.

                        INCENTIVE STOCK OPTION AGREEMENT

     Metabolix, Inc., a Delaware corporation (the "Company"), hereby grants as
of February 28, 2002 (the "Grant Date") to DAVID SCOTT (the "Employee"), an
option to purchase a maximum of 1,000 shares (the "Option Shares") of its Common
Stock, $.01 par value ("Common Stock"), at the price of $2.70 per share on the
following terms and conditions:

     1.   GRANT UNDER THE 1995 STOCK PLAN OF METABOLIX, INC. This option is
granted pursuant to and is governed by the 1995 Stock Plan of Metabolix, Inc.,
(the "Plan") and, unless the context otherwise requires, terms used herein shall
have the same meaning as in the Plan. Determinations made in connection with
this option pursuant to the Plan shall be governed by the Plan as it exists on
this date.

     2.   GRANT AS INCENTIVE STOCK OPTION: OTHER OPTIONS. This option is
intended to qualify as an incentive stock option under Section 422 of the
Internal Revenue Code of 1986, as amended (the "Code"). This option is in
addition to any other options heretofore or hereafter granted to the Employee by
the Company or any Related Corporation (as defined in the Plan), but a duplicate
original of this instrument shall not effect the grant of another option.

     3.   VESTING OF OPTION IF EMPLOYMENT CONTINUES. If the Employee has
continued to be employed by the Company or any Related Corporation on the
following dates, the Employee may exercise this option for the number of shares
of Common Stock set opposite the applicable date:

<Table>
                                             
     Less than one year from               -    0 shares
     September 1, 2000

     One year but less than                -    250 shares
     two years from September 1, 2000

     Two years but less than               -    an additional
     three years from September 1, 2000         250 shares

     Three years but less than             -    an additional
     four years from September 1, 2000          250 shares

     Four years or more from               -    an additional
     September 1, 2000                          250 shares
</Table>

The foregoing rights are cumulative and, while the Employee continues to be
employed by the Company or any Related Corporation, may be exercised on or
before the date which is ten years from the date this option is granted. All of
the foregoing rights are subject to Sections 4 and 5, as appropriate, if the
Employee ceases to be employed by the Company and all Related Corporations.

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                                       -2-

     4.   TERMINATION EMPLOYMENT.

          (a)  TERMINATION: If the Employee ceases to be employed by the Company
and all Related Corporations, other than by reason of death or disability as
defined in Section 5, no further installments of this option shall become
exercisable, and this option shall terminate after the passage of sixty (60)
days from the Employee's last day of employment, but in no event later than the
scheduled expiration date. In such a case, the Employee's only rights hereunder
shall be those winch are properly exercised before the termination of this
option.

     5.   DEATH; DISABILITY.

          (a)  DEATH: If the Employee dies while in the employ of the Company
or any Related Corporation, this option may be exercised, to the extent
otherwise exercisable on the date of his or her death, by the Employee's estate,
personal representative or beneficiary to whom this option has been assigned
pursuant to Section 10, at any time within 180 days after the date of death, but
not later than, the scheduled expiration date.

          (b)  DISABILITY: If the Employee ceases to be employed by the Company
and all Related Corporations by reason of his or her disability (as defined in
the Plan), this option may be exercised, to the extent otherwise exercisable on
the date of the termination of his or her employment, at any time within 180
days after such termination, but not later than the scheduled expiration date.

          (c)  EFFECT OF TERMINATION; At the expiration of the 180-day period
provided in paragraph (a) or (b) of this Section 5 or the scheduled expiration
date, whichever is the earlier, this option shall terminate and the only rights
hereunder shall be those as to which the option was properly exercised before
such termination.

     6.   PARTIAL EXERCISE. This option may be exercised in part at any time and
from time to time within the above limits, except that this option may not be
exercised for a fraction of a share unless such exercise is with respect to the
final installment of stock subject to this option and cash in lieu of a
fractional share must be paid, in accordance with Paragraph 13(G) of the Plan,
to permit the Employee to exercise completely such final installment. Any
fractional share with respect to which an installment of this option cannot be
exercised because of the limitation contained in the preceding sentence shall
remain subject to this option and shall be available for later purchase by the
Employee in accordance with the terms hereof.

     7.   PAYMENT OF PRICE. The option price shall be paid in United States
dollars in the following manner:

          (a)  in cash or by check, or any combination of the foregoing, equal
     in amount to the option price; or

          (b)  in the discretion of the Company's Board of Directors, in cash,
     by check, by delivery of shares of the Company's Common Stock having a fair
     market value (as determined by the Board of Directors) equal as of the date
     of exercise to the option price, or by any combination of the foregoing,
     equal in amount to the option price.

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                                       -3-

     Notwithstanding the foregoing, the Employee may not pay any part of the
exercise price hereof by transferring Common Stock to the Company if such
Company's Common Stock is both subject to a substantial risk of forfeiture and
not transferable within the meaning of Section 83 of the Code.

     8.   RESTRICTIONS ON RESALE. Option Shares may not be transferred without
the Company's written consent except by will, by the laws of descent and
distribution and in accordance with the provisions of Sections 17 and 18, if
applicable. Option Shares will be of an illiquid nature and will be deemed to be
"restricted securities" for purposes of the Securities Act of 1933, as amended.
Accordingly, such shares must be sold in compliance with the registration
requirements of such Act or an exemption therefrom.

     9.   METHOD OF EXERCISING OPTION. Subject to the terms and conditions of
this Agreement, this option may be exercised by written notice to the Company at
its principal executive office, or to such transfer agent as the Company shall
designate. Such notice shall state the election to exercise this option and the
number of Option Shares for which it is being exercised and shall be signed by
the person or persons so exercising this option. Such notice shall be
accompanied by payment of the full purchase price of such shares (as provided in
Section 7 hereof), and the Company shall deliver a certificate or certificates
representing such shares as soon as practicable after the notice shall be
received. Such certificate or certificates shall be registered in the name of
the person or persons so exercising this option (or, if this option shall be
exercised by the Employee and if the Employee shall so request in the notice
exercising this option, shall be registered in the name of the Employee and
another person jointly, with right of survivorship). In the event this option
shall be exercised, pursuant to Section 5 hereof, by any person or persons other
than the Employee, such notice shall be accompanied by appropriate proof of the
right of such person or persons to exercise this option.

     10.  OPTION NOT TRANSFERABLE. This option is not transferable or assignable
except by will or by the laws of descent and distribution. During the Employee's
lifetime only the Employee can exercise this option.

     11.  NO OBLIGATION TO EXERCISE OPTION. The grant and acceptance of this
option imposes no obligation on the Employee to exercise it.

     12.  NO OBLIGATION TO CONTINUE EMPLOYMENT. Neither the Plan, this
Agreement, nor the grant of this option imposes any obligation on the Company or
any Related Corporation to continue the Employee in employment.

     13.  NO RIGHTS AS STOCKHOLDER UNTIL EXERCISE. The Employee shall have no
rights as a stockholder with respect to the Option Shares until such time as the
Employee has exercised this option by delivering a notice of exercise and has
paid in full the purchase price for the shares so exercised in accordance with
Section 9. Except as is expressly provided in the Plan with respect to certain
changes in the capitalization of the Company, no adjustment shall be made for
dividends or similar rights for which the record date is prior to such date of
exercise.

     14.  CAPITAL CHANGES AND BUSINESS SUCCESSIONS. The Plan contains provisions
covering the treatment of options in a number of contingencies such as stock
splits and mergers. Provisions in the Plan for adjustment with respect to stock
subject to options and the related provisions with respect to successors to the
business of the Company are hereby made applicable hereunder and are
incorporated herein by reference. The Option Shares shall include all shares
issued in connection with such provisions.

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                                       -4-

     15.  EARLY DISPOSITION. The Employee agrees to notify the Company in
writing immediately after the Employee transfers any Option Shares, if such
transfer occurs on or before the later of (a) the date two years after the date
of this Agreement or (b) the date one year after the date the Employee acquired
such Option Shares. The Employee also agrees to provide the Company with any
information concerning any such transfer required by the Company for tax
purposes.

     16.  WITHHOLDING TAXES. If the Company or any Related Corporation in its
discretion determines that it is obligated to withhold any tax in connection
with the exercise of this option, or in connection with the transfer of, or the
lapse of restrictions on, any Common Stock or other property acquired pursuant
to this option, the Employee hereby agrees that the Company or any Related
Corporation may withhold from the Employee's wages or other remuneration the
appropriate amount of tax. At the discretion of the Company or Related
Corporation, the amount required to be withheld may be withheld in cash from
such wages or other remuneration or in kind from the Common Stock or other
property otherwise deliverable to the Employee on exercise of this option. The
Employee further agrees that, if the Company or any Related Corporation does not
withhold an amount from the Employee's wages or other remuneration sufficient to
satisfy the withholding obligation of the Company or Related Corporation, the
Employee will make reimbursement on demand, in cash, for the amount
underwithheld.

     17.  COMPANY'S RIGHT OF FIRST REFUSAL.

          (a)  EXERCISE OF RIGHT: If the Employee desires to transfer all or any
part of the Option Shares to any person other than the Company (an "Offeror"),
the Employee shall: (i) obtain in writing an irrevocable and unconditional bona
fide offer (the "Offer") for the purchase thereof from the Offeror; and (ii)
give written notice (the "Option Notice") to the Company setting forth the
Employee's desire to transfer such shares, which Option Notice shall be
accompanied by a photocopy of the Offer and shall set forth at least the name
and address of the Offeror and the price and terms of the Offer. Upon receipt of
the Option Notice, the Company shall have an assignable option to purchase any
or all of such Option Shares (the "Company Option Shares") specified in the
Option Notice, such option to be exercisable by giving, within 30 days after
receipt of the Option Notice, a written counter-notice to the Employee. If the
Company elects to purchase any or all of such Company Option Shares, it shall be
obligated to purchase, and the Employee shall be obligated to sell to the
Company, such Company Option Shares at the price and terms indicated in the
Offer within 30 days from the date of delivery by the Company of such
counter-notice.

          (b)  SALE OF OPTION SHARES TO OFFEROR: The Employee may, for 60 days
after the expiration of the 30-day option period as set forth in Section 17(a),
sell to the Offerer, pursuant to the terms of the Offer, any or all of such
Company Option Shares not purchased or agreed to be purchased by the Company or
its assignee; PROVIDED, HOWEVER, that the Employee shall not sell such Company
Option Shares to such Offeror if such Offeror is a competitor of the Company and
the Company gives written notice to the Employee, within 30 days of its receipt
of the Option Notice, stating that the Employee shall not sell his or her
Company Option Shares to such Offeror; and PROVIDED, FURTHER, that prior to the
sale of such Option Shares to an offerer, such Offeror shall execute an
agreement with the Company pursuant to which such Offeror agrees to be subject
to the restrictions set forth in this Section 17. If any or all of such Company
Option Shares are not sold pursuant to an Offer within the time permitted above,
the unsold Company Option Shares shall remain subject to the terms of this
Section 17.

          (c)  ADJUSTMENTS FOR CHANGES IN CAPITAL STRUCTURE: If there shall be
any change in the Common Stock of the Company through merger, consolidation,
reorganization, recapitalization,

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                                       -5-

stock dividend, stock split, combination or exchange of shares, or the like, the
restrictions contained in this Section 17 shall apply with equal force to
additional and/or substitute securities, if any, received by the Employee in
exchange for, or by virtue of his or her ownership of, Option Shares.

          (d)  FAILURE TO DELIVER OPTION SHARES: If the Employee fails or
refuses to deliver on a timely basis duly endorsed certificates representing
Company Option Shares to be sold to the Company or its assignee pursuant to this
Section 17, the Company shall have the right to deposit the purchase price for
such Company Option Shares in a special account with any bank or trust company
in the Commonwealth of Massachusetts, giving notice of such deposit to the
Employee, whereupon such Company Option Shares shall be deemed to have been
purchased by the Company. All such monies shall he held by the bank or trust
company for the benefit of the Employee. All monies deposited with the bank or
trust company but remaining unclaimed for two years after the date of deposit
shall be repaid by the bank or trust company to the Company on demand, and the
Employee shall thereafter look only to the Company for payment. The Company may
place a legend on any certificate for Option Shares delivered to the Employee
reflecting the restrictions on transfer provided in Section 8 hereof and this
Section 17,

          (e)  EXPIRATION OF COMPANY'S RIGHT OF FIRST REFUSAL: The first refusal
rights of the Company set forth above shall remain in effect until such time, if
ever, as a distribution to the public is made of shares of the Company's Common
Stock pursuant to a registration statement filed under the Securities Act of
1933, as amended, or a successor statute, at which time the refusal rights of
the Company set forth herein will automatically expire.

     18.  COMPANY'S RIGHT OF REPURCHASE.

          (a)  RIGHT OF REPURCHASE. The Company shall have the right (the
"Repurchase Right") to repurchase all of the Option Shares from the holder of
this option upon the occurrence of any of the events specified in Section 18(b)
below (the "Repurchase Event"). The Repurchase Right may be exercised by the
Company within 60 days following the later of the date of the exercise of this
option or the date the Company receives actual knowledge of such event (the
"Repurchase Period"). The Repurchase Right shall be exercised by the Company by
giving the holder written notice on or before the last day of the Repurchase
Period of its intention to exercise the Repurchase Right, and, together with
such notice, tendering to the holder an amount equal to the greater of the
option price or the fair market value of the shares. The Company may assign the
Repurchase Right to one or more persons. Upon timely exercise of the Repurchase
Right in the manner provided in this Section 18(a), the holder shall deliver to
the Company the stock certificate or certificates representing the shares being
repurchased, duly endorsed and free and clear of any and all liens, charges and
encumbrances.

     If shares are not purchased under the Repurchase Right, the Employee and
his or her successor in interest, if any, will hold any such shares in his or
her possession subject to all of the provisions of tin's Agreement.

          (b)  COMPANY'S RIGHT TO EXERCISE REPURCHASE RIGHT: The Company shall
have the Repurchase Right in the event that any of the following events shall
occur:

               (i)    The termination of the Employee's employment with the
     Company and all Related Corporations, voluntarily or involuntarily, for any
     reason whatsoever including death or permanent disability;

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                                       -6-

               (ii)   The receivership, bankruptcy or other creditor's
     proceeding regarding the Employee or the taking of any of Employee's shares
     acquired upon exercise of tins option by legal process, such as a levy of
     execution; or

               (iii)  Distribution of shares held by the Employee to his or her
     spouse as such spouse's joint or community interest pursuant to a decree of
     dissolution, operation of law, divorce, property settlement agreement or
     for any other reason, except as may be otherwise permitted by the Company.

          (c)  DETERMINATION OF FAIR MARKET VALUE: The fair market value of the
Option Shares shall be, for purposes of this Section 18, determined in
accordance with Section 6D of the Plan as of the date of the Repurchase Event.
The determination by the Board of Directors of the fair market value shall be
conclusive and binding.

          (d)  EXPIRATION OF COMPANY'S REPURCHASE RIGHT: The Repurchase Right
shall remain in effect until such time, if ever, as (i) the Option Shares are
transferred in accordance with Section 17 hereof or (ii) a distribution to the
public is made of shares of the Company's Comrnon Stock pursuant to a
registration statement filed under the Securities Act of 1933, as amended, or
any successor statute.

     19.  LOCK-UP AGREEMENT. The Employee agrees that in connection with an
underwritten public offering of Common Stock, upon the request of the Company or
the principal underwriter managing such public offering, this Option and the
Option Shares may not be sold, offered for sale or otherwise disposed of without
the prior written consent of the Company or such underwriter, as the case may
be, for at least 180 days after the effectiveness of the Registration Statement
filed in connection with such offering, or such longer period of time as the
Board of Directors may determine if all of the Company's directors and officers
agree to be similarly bound. The lock-up agreement established pursuant to this
paragraph 19 shall have perpetual duration.

     20.  PROVISION OF DOCUMENTATION TO EMPLOYEE. By signing this Agreement the
Employee acknowledges receipt of a copy of this Agreement and a copy of the
Plan.

     21.  MISCELLANEOUS.

          (a)  NOTICES: All notices hereunder shall be in writing and shall be
deemed given when sent by certified or registered mail, postage prepaid, return
receipt requested, to the address set forth below. The addresses for such
notices may be changed from time to time by written notice given in the manner
provided for herein.

          (b)  ENTIRE AGREEMENT; MODIFICATION: This Agreement constitutes the
entire agreement between the parties relative to the subject matter hereof, and
supersedes all proposals, written or oral, and all other communications between
the parties relating to the subject matter of this Agreement. This Agreement
may be modified, amended or rescinded only by a written agreement executed by
both parties.

          (c)  SEVERABILITY: The invalidity, illegality or unenforceability of
any provision of this Agreement shall in no way affect the validity, legality or
enforceability of any other provision.

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                                       -7-

          (d)  SUCCESSORS AND ASSIGNS: This Agreement shall be binding upon and
inure to the benefit of the parties hereto and their respective successors and
assigns, subject to the limitations set forth in Section 10 hereof.

          (c)  GOVERNING LAW: This Agreement shall be governed by and
interpreted in accordance with the laws of the Commonwealth of Massachusetts
without giving effect to the principles of the conflicts of laws thereof.

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     IN WITNESS WHEREOF, the Company and the Employee have caused this
instrument to be executed as of the date first above written.


/s/ David Scott                       METABOLIX, INC.
- ------------------------------        303 Third Street
Employee                              Cambridge, MA 02142-1196

DAVID SCOTT                           By: /s/ James Barber
- ------------------------------            -----------------------------------
Print Name of Employee                    James Barber
                                          President and Chief Executive Officer
27 Calvin St. #1
- ------------------------------
Street Address

Somerville,  MA      02143
- ------------------------------
City   State      Zip Code