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                                                                   Exhibit 10.41

                           CREATIVE BIOMOLECULES, INC.
                          EMPLOYEE STOCK PURCHASE PLAN
                           (as amended April 16, 1998)

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            Creative BioMolecules, Inc., a Delaware corporation (the "Company")
establishes this Employee Stock Purchase Plan (the "Plan") so that eligible
employees of the Company and Affiliated Companies, if any, may be granted
options to purchase Common Stock of the Company.

 1.         Purpose.

            The Plan provides Eligible Employees an opportunity to acquire
shares of Company Common Stock, $.01 par value, under circumstances which enable
them to obtain the income tax benefits described in Code Section 423. The Plan
is intended to provide employees incentive to continue to promote the Company's
best interests and to enhance its long-term performance.

 2.         Definitions.

            Wherever used, the following words and phrases will have the
meanings stated below unless a different meaning is plainly required by the
context:

"Affiliated Company" means any subsidiary corporation of the Company, as defined
in Code Sections 424(f).

"Applicable Grant Date" means for any Option the date on which such Option was
granted, which shall be the Effective Date or a Semiannual Grant Date, as the
case may be.

"Board" means the Board of Directors of the Company.

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

"Committee" means a committee appointed by the Board to which the Board may
delegate its powers to administer the Plan.

"Common Stock" means shares of the common stock of the Company,
$.01 par value.

"Company" means Creative BioMolecules, Inc., a Delaware
corporation.

"Compensation" means the total cash remuneration a Participant receives during
an Exercise Period as salary or wages, including overtime pay and bonuses and
excluding all other forms of remuneration.

"Disability" means permanent and total disability as defined in
Code Section 22(e)(3).

"Effective Date" means the effective date of a registration statement under the
Securities Act of 1933, as amended, for the shares of Common Stock to be issued
pursuant to the Plan. Filing of any such registration statement is at the
discretion of the Company.
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"Eligible Employee" means each person who, on the Effective Date or on an
applicable Semiannual Grant Date, is employed by the Company or an Affiliated
Company and has been an employee for 3 or more months at that date. An employee
will not be eligible to participate during an Exercise Period if his or her
customary employment as of the first day of the period is either less than 20
hours per week or 5 months or less on a calendar year basis. No employee will be
eligible if he or she is an owner of 5% or more of the stock of the Company or
an Affiliated Company, as determined under Code Section 423(b)(3). In addition,
in no event may any person subject to Section 16 of the Exchange Act who has
ceased participation (within the meaning of Rule 16b-3) be considered an
Eligible Employee for participation until at least six months have elapsed from
the date participation ended.

"Exchange Act" means the Securities Exchange Act of 1934.

"Exercise Date" means any date on which an Eligible Employee purchases Common
Stock pursuant to an Option under this Plan, which shall, with respect to each
Option, be the last day of the Exercise Period in which such Option is granted.

"Exercise Period" means the six month period commencing on an Applicable Grant
Date and ending at 5 p.m on June 30 or December 31, as applicable. However, the
first exercise period commences on the Effective Date and ends at 5 p.m on
December 31, 1992. If the Plan is terminated, then the Exercise Period in which
it is terminated shall end on the date immediately preceding the effective date
of such termination. If any of the preceding ending dates falls on a Saturday,
Sunday or legal holiday in the Commonwealth of Massachusetts, then that Exercise
Period shall end on the day most closely preceding such date which is not a
Saturday, Sunday or legal holiday in the Commonwealth of Massachusetts.

"Fair Market Value Per Share of Common Stock" shall mean (i) the average (on
that date) of the high and low prices of the Common Stock on the principal
national securities exchange on which the Common Stock is traded, if the Common
Stock is then traded on a national securities exchange, or on the NASDAQ
National Market System, if the Common Stock is not then traded or a national
securities exchange; or (ii) the closing bid price (or average of bid prices)
last quoted (on that day) by an established quotation service for
over-the-counter securities, if the Common Stock is not reported on the NASDAQ
National Market System. If the Common Stock is neither listed on a national
securities exchange nor reported on the NASDAQ National Market System nor traded
on the over-the-counter market, fair market value shall be such value as the
Board, in good faith, determines. Notwithstanding any provision of the Plan to
the contrary, no determination made with respect to the Fair Market Value of
Common Stock subject to an Option shall be inconsistent with Code Section 423.

"Initial Notice Period" means the period beginning on the Effective Date and
ending on the 15th day thereafter.


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"Notice Period" means that period beginning 30 days prior to the applicable
Semiannual Grant Date and ending on the 15th day prior to said date.

"Option" means an option granted hereunder which will entitle an Eligible
Employee to purchase shares of Common Stock.

"Option Price" means the lower of: (1) 85% of the Fair Market Value per share of
Common Stock as of the Applicable Grant Date on which the Option being exercised
was granted or (2) 85% of the Fair Market Value per share of Common Stock as of
the Exercise Date on which such Option is exercised.

"Participant" means an Eligible Employee who has elected to participate in the
Plan during the period between such election and the termination of such
Eligible Employee's participation in the Plan.

"Plan" means the Creative BioMolecules, Inc. Employee Stock Purchase Plan as set
forth herein.

"Retirement" is a termination on or after the first day of the month of a
Participant's 65th birthday.

"Semiannual Grant Date" means each January 1 and July 1 following the completion
of the first Exercise Period. If any of the dates falls on a Saturday, Sunday or
legal holiday in the Commonwealth of Massachusetts, then that Exercise Period
shall end on the day most closely succeeding such date which is not a Saturday,
Sunday or legal holiday in the Commonwealth of Massachusetts.

"Withholding Account" means a bookkeeping record of all amounts withheld during
an Exercise Period for a specific Eligible Employee, which are available for the
exercise of an Option granted hereunder. Specific segregation of funds is not
required.

3.          Administration.

            The Plan shall be administered by the Board, which, to the extent it
shall determine, may delegate its powers with respect to the administration of
the Plan (except its powers to terminate or amend the Plan) to the Committee. If
the Board chooses to appoint a Committee, references hereinafter to the Board
shall be deemed to refer to the Committee. Subject to the express provisions of
the Plan, the Board may interpret the Plan, prescribe, amend and rescind rules
and regulations relating to it, determine the terms and provisions of the
Options granted hereunder and make all other determinations necessary or
advisable for the administration of the Plan; provided, however, that all such
interpretations, rules, determinations, terms and conditions shall be made and
prescribed in the context of preserving the tax treatment of the Options under
this Plan granted to Eligible Employees subject to United States Federal Income
Taxation and the Plan itself under Section 423 of the Code. In addition, this
Plan is intended to comply in all respects with Rule 16b-3 or its successor
promulgated under the 1934 Act with respect to participants who are subject to
Section


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16 of the 1934 Act. Any provision in this Plan with respect to such persons
contrary to Rule 16b-3 shall be modified to the extent necessary for such
provision to comply with Rule 16b-3 to the extent permissible by law and deemed
appropriate by the Board. The determinations of the Board on all matters
regarding the Plan shall be conclusive.

4.          Maximum Shares to be Granted under the Plan.

            The aggregate number of shares of Common Stock available for grant
as Options pursuant to Section 5 shall not exceed seven-hundred fifty thousand
(750,000), subject to adjustment pursuant to Section 9. Shares of Common Stock
granted pursuant to the Plan may either be authorized but unissued shares or
shares now or hereafter held in the treasury of the Company. In the event that
any Option granted pursuant to Section 5 expires or is terminated, surrendered
or cancelled without being exercised, in whole or in part, for any reason, the
number of shares of Common Stock theretofore subject to such Option shall again
be available for grant as an Option pursuant to Section 5 and shall not reduce
the aggregate number of shares of Common Stock available for grant as such
Options, as set forth in the first sentence of this Section.

5.          Eligibility for Participation and Granting of Options.

            (a) Each employee of the Company who enrolls in the Plan and who is
an Eligible Employee on the Effective Date or a Semiannual Grant Date, as the
case may be, is granted without any further action by Company an Option
hereunder which will entitle him or her to purchase, on the immediately
following Exercise Date at the Option Price per share for Options granted on
such date, shares of Common Stock equal in value up to fifteen percent (15%) of
the Eligible Employee's Compensation during the Election Period divided by such
applicable Option Price per share of Common Stock.

            (b) If the number of shares of Common Stock for which Options are
granted pursuant to paragraph 5(a) exceeds the applicable number set forth in
Section 4, then the Options granted under paragraph 5(a) to all Eligible
Employees shall, in a nondiscriminatory manner, be reduced on a pro rata basis
in a manner which the Board determines to be consistent with Code Section 423.

            (c) No Eligible Employee shall be granted an Option under the Plan
which permits his or her rights to purchase stock under all employee stock
purchase plans (as defined in Code Section 423) of the Company and any
Affiliated Company to accrue at a rate which exceeds $25,000 of fair market
value of such stock (determined at the time of the grant of such Option) for
each calendar year in which such Option is outstanding at any time. Any Option
granted under the Plan shall be deemed to be modified to the extent necessary to
satisfy this paragraph.


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6.          Terms of Options.

            (a) Each Option shall automatically be exercised on the last day of
the Exercise Period for such Option, using the funds which have accrued in a
Participant's Withholding Account as of such day, unless the Participant
withdraws from the Plan or is deemed to withdraw during the Exercise Period. An
Option granted hereunder may be exercised only through the use of the funds
which have accrued in a Participant's Withholding Account. Any Option, to the
extent unexercised on the Exercise Date, shall expire on the Exercise Date.

            (b) As soon as reasonably possible following exercise in accordance
with Paragraph 6(a) and upon the Participant's written request, a certificate
representing the whole number of shares of Common Stock purchased, registered in
the name of the Optionee, shall be delivered to the Optionee or to such other
person designated by Optionee including, without limitation, the Participant's
broker.

            (c) A Participant shall be deemed to have withdrawn from
participation in the Plan upon the occurrence of any of the following:

                (i) Voluntary discontinuance while employed. A Participant may
discontinue his or her election and withdraw from this Plan by giving written
notice to the Company no later than the last day of the Notice Period within
that Exercise Period, specifying that the Participant is so withdrawing from the
Plan, provided, however, that a Participant who shall have discontinued his or
her election to participate and withdrawn from this Plan may not participate in
the Plan during the next following Offering Period.

                (ii) Termination of employment. Unless employment has terminated
due to Retirement, Disability or death, a Participant will be deemed to have
discontinued participation on the first day of the Exercise Period in which
termination occurs and amounts withheld from compensation during the Exercise
Period will be refunded without election by the Participant.

                (iii) Retirement. In the event a Participant's employment
terminates because of Retirement during the first three months of an Exercise
Period, the Participant will be deemed to have discontinued participation on the
first day of the Exercise Period in which Retirement occurs and amounts withheld
from Compensation during the Exercise Period will be refunded. If Retirement
occurs during the last three months of the Exercise Period, the Participant will
continue to participate through the balance of the Exercise Period in which
Retirement occurs (without further withholding) unless he or she elects a
voluntary discontinuance within the Notice Period for that Exercise Period.

                (iv) Death or Disability. In the event the employment of the
Participant by the Company or an Affiliated Company terminates as a result of
the Participant's Disability or Death, the Participant will be deemed to
participate (without further withholding) through the balance of the Exercise
Period in which


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death or Disability occurs, unless he or she (or the executor, administrator or
representative, as the case may be) elects a voluntary discontinuance within the
Notice Period for that Exercise Period.

                (v) Levy or attachment. The filing with or levying upon the
Company or the custodian of any judgment, attachment, garnishee, or other Court
order affecting the Participant's account under this Plan will terminate his or
her participation.

                (vi) Plan Termination/ Expiration. The termination of this Plan
by the Company prior to its expiration or its expiration upon allocation of all
available shares will terminate participation.

            (d) A Participant's employment shall not be deemed terminated by
reason of a transfer to another employer which is related to the Company within
the meaning of Code Sections 423 (e) or (f). A Participant who has elected
participation under the Plan who is absent from work with the Company or with an
Affiliated Company because of temporary disability (any disability other than a
permanent and total Disability) or who is on leave of absence for a period of
less than 90 days shall not, during the period of any such absence, be deemed,
by virtue of such absence alone, to have terminated employment. In the case of a
leave of absence which is longer than 90 days, a Participant will not be deemed
to have terminated employment until the later of the 91st day of such leave or,
if later, such date as the Participant's reemployment rights are not protected
by contract or law.

            (e) Upon the discontinuance of an election and withdrawal from this
Plan by a Participant, all withheld amounts in the account which are
attributable to such Participant shall be transferred to such Participant within
thirty (30) days of such discontinuance and withdrawal, except to the extent
such withheld amounts are applied to the exercise of an Option as provided
above. In no event shall any amounts be withheld from a Participant's
Compensation for allocation to such Participant's Withholding Account after the
date such Participant's employment shall cease.

            (f) In no event may any discontinuance of a Participant's election
and withdrawal from this Plan be in respect to a portion rather than all of such
Participant's Withholding Account on such date.

7.          Payment for Common Stock Through Withholding.

            (a) Employee Contributions

            Each Eligible Employee may elect to participate in this Plan by
filing an enrollment application and payroll withholding form with his or her
employer's payroll department during the Initial Notice Period or during a
Notice Period, which election shall be effective in the case of an election
filed during the Initial Notice Period, for the Exercise Period commencing on
the Effective Date and all subsequent Exercise Periods, or, in the


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case of an election filed during a Notice Period, for the next Exercise Period
and for all subsequent Exercise Periods, until, in any case, such Participant's
participation in the Plan terminates. Each Eligible Employee who elects to
participate shall specify the amount of his or her contributions to be made by
payroll deduction by specifying a whole percentage from 1% to 15% of such
Participant's Compensation payable for each payroll period.

            No interest shall accrue or be payable to any Participant in the
Plan with respect to any sums withheld at the Participant's election, whether
such sums be applied to purchase Common Stock, or are returned to the
Participant.

            Payroll deductions may be increased by a Participant only during a
subsequent Notice Period, but may be decreased, upon the Participant's written
election, effective as of the first payroll period for which it is
administratively practical to put the decrease into effect.

            (b) Application of Payroll Contributions

            The Company shall maintain a separate account into which it shall
deposit all amounts withheld for payment of shares of Common Stock and shall
maintain sufficient records to show each Participant's Withholding Account.

            On the last day of each Exercise Period all amounts in a
Participant's Withholding Account shall be paid over to the Company in payment
of the Option Price for the number of whole shares of Common Stock which can be
purchased on such date with such withheld total amount, unless otherwise
directed in accordance with Section 6 above. In lieu of fractional shares,
unapplied cash shall be carried forward to the next Exercise Period unless the
Participant requests a cash payment.

8.          Transferability of Options and Common Stock.

            (a) No Option may be transferred, assigned, pledged, or hypothecated
(whether by operation of law or otherwise), except as provided by will or the
applicable laws of descent or distribution, and no Option shall be subject to
execution, attachment or similar process. Any attempted assignment, transfer,
pledge, hypothecation or other disposition of an Option, or levy of attachment
or similar process upon the Option not specifically permitted herein shall be
null and void and without effect. An Option may be exercised only by the
Eligible Employee during his or her lifetime, or by his or her legal
representative if permitted by Section 423 of the Code, or pursuant to Section 6
by his or her estate or the person who acquires the right to exercise such
Option upon his or her death by bequest or inheritance.

            (b) Participants in the Plan who wish to avail themselves of the
favorable tax benefits of Code Section 423 may not transfer or otherwise dispose
of shares of Common Stock acquired by them or on their behalf under this Plan
(other than in the case of a Participant's death) until after the later of one
year


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from the date of acquisition of said shares or two years after the Applicable
Grant Date of the Option pursuant to which said shares of Common Stock were
acquired. In the case of any person subject to Section 16 of the 1934 Act,
shares purchased under this Plan must be held for six months from the Exercise
Date in order for the Participant to obtain the benefit of Rule 16b-3.

            (c) Each Eligible Employee who receives shares of Common Stock
pursuant to this Plan agrees, by electing to participate, to notify the Company,
in writing, immediately after such Participant makes a Disqualifying Disposition
of any shares acquired pursuant to the exercise of an Option under this Plan. A
Disqualifying Disposition is any disposition (including any sale) of such shares
before the later of two years after the Applicable Grant Date for said Option or
one year after the receipt of shares pursuant to the exercise of said Option. If
the Participant has died before such stock is sold, these holding period
requirements do not apply and no Disqualifying Disposition can occur thereafter.

 9.         Adjustment Provisions.

            The aggregate number of shares of Common Stock with respect to which
Options may be granted, the aggregate number of shares of Common Stock subject
to each outstanding Option, and the Option Price per share of each Option shall
all be appropriately adjusted for any increase or decrease in the number of
shares of issued Common Stock resulting from a subdivision or consolidation of
shares, whether through reorganization, recapitalization, stock split-up, stock
distribution or combination of shares, or the payment of a share dividend or
other increase or decrease in the number of such shares outstanding effected
without receipt of consideration by the Company. Adjustments shall be made
according to the sole discretion of the Board, and its decision shall be binding
and conclusive.

10.         Dissolution, Merger and Consolidation.

            Upon the dissolution or liquidation of the Company, or upon a merger
or consolidation of the Company in which the Company is not the surviving
corporation, the holder of each Option then outstanding under the Plan will
thereafter be entitled to receive at the next Exercise Date upon the exercise of
such Option for each share as to which such Option shall be exercised, as nearly
as reasonably may be determined, the cash, securities and/or property which a
holder of one share of the Common Stock was entitled to receive upon and at the
time of such transaction. The Board shall take such steps in connection with
such transactions as the Board shall deem necessary to assure that the
provisions of this Section 10 shall thereafter be applicable, as nearly as
reasonably may be determined, in relation to the said cash, securities and/or
property as to which such holder of such Option might thereafter be entitled to
receive.

11.         Shareholder Approval.

            The Plan is subject to approval by the holders of a majority of the
outstanding shares of Common Stock (and the holders of any


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other class of stock to the extent required by agreement or Code Section 423)
within 12 months before or after the date of adoption of the Plan by the Board.
The Plan shall be null and void and of no effect if the foregoing condition is
not fulfilled.

12.         Miscellaneous.

            (a) Legal and Other Requirements. The obligations of the Company to
sell and deliver Common Stock under the Plan shall be subject to all applicable
laws, regulations, rules and approvals, including, but not by way of limitation,
the effectiveness of a registration statement under the Securities Act of 1933
if deemed necessary or appropriate by the Company. Certificates for shares of
Common Stock issued hereunder may be legended as the Board shall deem
appropriate.

            (b) Termination and Amendment of Plan. Except as provided in the
following sentence, the Plan may be terminated or amended by the shareholders,
by the Board, or by the Committee, including amendment of the Plan from time to
time to designate corporations whose employees may be offered options under the
plan from among a group consisting of the Company and any corporation which is
or becomes its Affiliate. Amendments effecting: (1) any increase in the
aggregate number of shares which may be issued under the Plan (other than an
increase merely reflecting a change in capitalization such as a stock dividend
or stock split) or (2) changing the designation of corporations whose employees
may be offered options under the Plan, except designations described in the
preceding sentence, must be approved by the shareholders within twelve (12)
months after such amendment is adopted by the Board or by the Committee or such
amendment is void ab initio. No amendment shall affect any Options theretofore
granted or any Common Stock theretofore acquired by a Participant, unless such
amendment shall expressly so provide and unless any Participant to whom an
Option has been granted who would be adversely affected by such amendment
consents in writing thereto. If the scope of any amendment is such as to require
shareholder approval in order to comply with Rule 16b-3 under the 1934 Act, then
such amendment shall also require approval by the shareholders.

            (c) Application of Funds. The proceeds received by the Company from
the sale of Common Stock pursuant to Options will be used for general corporate
purposes.

            (d) Withholding Taxes. Upon a Disqualifying Disposition, within the
meaning of Paragraph 8(c), of any shares of Common Stock received pursuant to
the exercise of any Option under the Plan, the Company shall have the right to
require the Participant to remit to the Company an amount sufficient to satisfy
all federal, state and local requirements as to income tax withholding and
employee contributions to employment taxes or, alternatively, in the Board's
sole discretion, the Company may withhold all such amounts from other cash
compensation then being paid to the Participant by the Company.

            (e) Right to Terminate Employment. Nothing in the Plan or any
agreement entered into pursuant to the Plan shall confer upon


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any Eligible Employee or other optionee the right to continue in the employment
of the Company or any Affiliated Company or affect any right which the Company
or any Affiliated Company may have to terminate the employment of such Eligible
Employee or other optionee.

            (f) Rights as a Shareholder. A Participant shall not have any right
as a shareholder with respect to shares of Common Stock issuable pursuant to the
exercise of an Option hereunder, unless and until a certificate or certificates
for such shares of Common Stock are issued to him or her or the Company reflects
the Participant's ownership in its stock ledger or other appropriate record of
Common Stock ownership.

            (g) Leaves of Absence. The Board shall be entitled to make such
rules, regulations and determinations as it deems appropriate under the Plan in
respect of any leave of absence taken by any Eligible Employee, provided such
rules are consistent with Code Section 423.

            (h) Notices. Every direction, revocation or notice authorized or
required by the Plan shall be deemed delivered to the Company (1) on the date it
is personally delivered to the Treasurer of the Company (or such other person as
may be designated by the Company from time to time with notice given to each
Participant) at its principal executive offices or (2) three business days after
it is sent by registered or certified mail, postage prepaid, addressed to the
Treasurer of the Company (or such other person as may be designated by the
Company from time to time with notice given to each Participant) at such offices
or (3) on the date on which delivery was guaranteed by a third party business
(such as Federal Express and including the postal service); and shall be deemed
delivered to a Participant (1) on the date it is personally delivered to him or
her or (2) three business days after it is sent by registered or certified mail,
postage prepaid, addressed to him or her at the last address shown for him or
her on the records of the Company or of any Affiliate or (3) on the date on
which delivery was guaranteed by a third party business (such as Federal Express
and including the postal service), provided that the documents were sent to him
or her at the last address shown for him or her on the records of the Company or
of any Affiliate.

            (i) All Eligible Employees shall have the same rights and privileges
under the Plan, except that the amount of Common Stock which may be purchased
under Options granted under this Plan shall bear a uniform relationship to the
Compensation of Eligible Employees. All rules and determinations of the Board in
the administration of the Plan shall be uniformly and consistently applied to
all persons in similar circumstances.

            (j) Applicable Law. All questions pertaining to the validity,
construction and administration of the Plan and Options granted hereunder shall
be determined in conformity with the law of Delaware, to the extent not
inconsistent with Section 423 of the Code and regulations thereunder.


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