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                                  EXHIBIT 10.1


                          GELTEX PHARMACEUTICALS, INC.

                 AMENDED AND RESTATED 1992 EQUITY INCENTIVE PLAN


Section 1. PURPOSE

     The purpose of the GelTex Pharmaceuticals, Inc. Amended and Restated 1992
Equity Incentive Plan (the "Plan") is to attract and retain key employees and
consultants, to provide an incentive for them to achieve long-range performance
goals, and to enable them to participate in the long-term growth of the Company.

Section 2. DEFINITIONS

     "Affiliate" means any business entity in which the Company owns directly or
indirectly 50% or more of the total combined voting power or has a significant
financial interest as determined by the Committee.

     "Award" means any Option, Stock Appreciation Right, Performance Share,
Restricted Stock, Stock Unit or Other Stock-Based Award awarded under the Plan.

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

     "Code" means the Internal Revenue Code of 1986, as amended from time to
time, and any successor to such Code.

     "Committee" means a committee of not less than two members of the Board
appointed by the Board to administer the Plan; provided, however, that until
such committee is appointed, "Committee" means the Board.

     "Common Stock" or "Stock" means the Common Stock, $0.01 par value, of the
Company.

     "Company" means GelTex Pharmaceuticals, Inc.

     "Designated Beneficiary" means the beneficiary designated by a Participant,
in a manner determined by the Committee, to receive amounts due or exercise
rights of the Participant in the event of the Participant's death. In the
absence of an effective designation by a Participant, "Designated Beneficiary"
shall mean the Participant's estate.

     "Effective Date" means June 1, 1992.

     "Fair Market Value" means, with respect to Common Stock or any other
property, the fair market value of such property as determined by the Committee
in good faith or in the manner established by the Committee from time to time.

     "Incentive Stock Option" means an option to purchase shares of Common Stock
awarded to a Participant under Section 6 that is intended to meet the
requirements of Section 422 of the Code or any successor provision.

     "Nonstatutory Stock Option" means an option to purchase shares of Common
Stock


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awarded to a Participant under Section 6 that is not intended to be an Incentive
Stock Option.

     "Option" means an Incentive Stock Option or a Nonstatutory Stock Option.

     "Other Stock-Based Award" means an Award, other than an Option, Stock
Appreciation Right, Performance Share, Restricted Stock or Stock Unit, having a
Common Stock element and awarded to a Participant under Section 11.

     "Participant" means a person selected by the Committee to receive an Award
under the Plan.

     "Performance Cycle" or "Cycle" means the period of time selected by the
Committee during which performance is measured for the purpose of determining
the extent to which an award of Performance Shares has been earned.

     "Performance Shares" mean shares of Common Stock, which may be earned by
the achievement of performance goals, awarded to a Participant under Section 8.

     "Reporting Person" means a person subject to Section 16 of the Securities
Exchange Act of 1934 or any successor provision.

     "Restricted Period" means the period of time during which an Award may be
forfeited to the Company pursuant to the terms and conditions of such Award.

     "Restricted Stock" means shares of Common Stock subject to forfeiture
awarded to a Participant under Section 9.

     "Stock Appreciation Right" or "SAR" means a right to receive any excess in
value of shares of Common Stock over the exercise price awarded to a Participant
under Section 7.

     "Stock Unit" means an award of Common Stock or units that are valued in
whole or in part by reference to, or otherwise based on, the value of Common
Stock, awarded to a Participant under Section 10.

Section 3. ADMINISTRATION

     The Plan shall be administered by the Committee; provided, however, that
any duties described herein as duties of the Committee may at all times be
conducted by the Board as a whole, in its discretion. The Committee shall have
authority to adopt, alter and repeal such administrative rules, guidelines and
practices governing the operation of the Plan as it shall from time to time
consider advisable, and to interpret the provisions of the Plan. The Committee's
decisions shall be final and binding. To the extent permitted by applicable law,
the Committee may delegate to one or more executive officers of the Company the
power to make Awards to Participants who are not Reporting Persons and all
determinations under the Plan with respect thereto, provided that the Committee
shall fix the maximum amount of such Awards for the group and a maximum for any
one Participant.

Section 4. ELIGIBILITY

     All employees and, in the case of Awards other than Incentive Stock
Options, consultants and members of the Board or any Affiliate capable of
contributing significantly to the successful performance of the Company, other
than a person who has 



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irrevocably elected not to be eligible, are eligible to be Participants in the
Plan. Incentive Stock Options may be awarded only to persons eligible to receive
such Options under the Code.

Section 5. STOCK AVAILABLE FOR AWARDS

     (a)  Subject to adjustment under subsection (c), Awards may be made under
the Plan for up to 2,750,000 shares of Common Stock. If any Award in respect of
shares of Common Stock expires or is terminated unexercised or is forfeited
without the Participant having had the benefits of ownership (other than voting
rights), the shares subject to such Award, to the extent of such expiration,
termination or forfeiture, shall again be available for award under the Plan.
Common Stock issued through the assumption or substitution of outstanding grants
from an acquired company shall not reduce the shares available for Awards under
the Plan. Shares issued under the Plan may consist in whole or in part of
authorized but unissued shares or treasury shares.

     (b)  Subject to adjustment under subsection (c), no Participant may receive
an Award which would result in such Participant having received, during the
fiscal year of the Company in which the Award is made, Awards for more than an
aggregate of 250,000 shares of Common Stock.

     (c)  In the event that the Committee in its discretion determines that any
stock dividend, extraordinary cash dividend, creation of a class of equity
securities, recapitalization, reorganization, merger, consolidation, split-up,
spin-off, combination, exchange of shares, warrants or rights offering to
purchase Common Stock at a price substantially below fair market value, or other
similar transaction affects the Common Stock such that an adjustment is required
in order to preserve the benefits or potential benefits intended to be made
available under the Plan, then the Committee (subject, in the case of Incentive
Stock Options, to any limitation required under the Code) shall equitably adjust
any or all of (i) the number and kind of shares in respect of which Awards may
be made under the Plan, (ii) the number and kind of shares subject to
outstanding Awards, and (iii) the award, exercise or conversion price with
respect to any of the foregoing, and if considered appropriate, the Committee
may make provision for a cash payment with respect to an outstanding Award,
provided that the number of shares subject to any Award shall always be a whole
number.

Section 6. STOCK OPTIONS

     (a)  Subject to the provisions of the Plan, the Committee may award
Incentive Stock Options and Nonstatutory Stock Options and determine the number
of shares to be covered by each Option, the option price therefor and the
conditions and limitations applicable to the exercise of the Option. The terms
and conditions of Incentive Stock Options shall be subject to and comply with
Section 422 of the Code, or any successor provision, and any regulations
thereunder, and no Incentive Stock Option may be granted hereunder more than ten
years after the Effective Date.

     (b)  The Committee shall establish the option price at the time each Option
is awarded, which price shall not be less than 100% of the Fair Market Value of
the Common Stock on the date of award with respect to Incentive Stock Options.
Nonstatutory Stock Options may be granted at such prices as the Committee may
determine.

     (c)  Each Option shall be exercisable at such times and subject to such
terms and conditions as the Committee may specify in the applicable Award or
thereafter. The Committee may impose such conditions with respect to the
exercise of Options, including conditions relating



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to applicable federal or state securities laws, as it considers necessary or
advisable.

     (d)  No shares shall be delivered pursuant to any exercise of an Option
until payment in full of the option price therefor is received by the Company.
Such payment may be made in whole or in part in cash or, to the extent permitted
by the Committee at or after the award of the Option, by delivery of a note or
shares of Common Stock owned by the optionee, including Restricted Stock, valued
at their Fair Market Value on the date of delivery, or such other lawful
consideration as the Committee may determine.

     (e)  The Committee may provide that, subject to such conditions as it
considers appropriate, upon the delivery of shares to the Company in payment of
an Option, the Participant shall automatically be awarded an Option for up to
the number of shares so delivered.

Section 7. STOCK APPRECIATION RIGHTS

     (a)  Subject to the provisions of the Plan, the Committee may award SARs in
tandem with an Option (at or after the award of the Option), or alone and
unrelated to an Option. SARs in tandem with an Option shall terminate to the
extent that the related Option is exercised, and the related Option shall
terminate to the extent that the tandem SARs are exercised. SARs granted in
tandem with Options shall have an exercise price not less than the exercise
price of the related Option. SARs granted alone and unrelated to an Option may
be granted at such exercise prices as the Committee may determine.

     (b)  An SAR related to an Option that can only be exercised during limited
periods following a change in control of the Company may entitle the Participant
to receive an amount based upon the highest price paid or offered for Common
Stock in any transaction relating to the change in control or paid during the
thirty-day period immediately preceding the occurrence of the change in control
in any transaction reported in the stock market in which the Common Stock is
normally traded.

Section 8. PERFORMANCE SHARES

     (a)  Subject to the provisions of the Plan, the Committee may award
Performance Shares and determine the number of such shares for each Performance
Cycle and the duration of each Performance Cycle. There may be more than one
Performance Cycle in existence at any one time, and the duration of Performance
Cycles may differ from each other. The payment value of Performance Shares shall
be equal to the Fair Market Value of the Common Stock on the date the
Performance Shares are earned or, in the discretion of the Committee, on the
date the Committee determines that the Performance Shares have been earned.

     (b)  The Committee shall establish performance goals for each Cycle, for
the purpose of determining the extent to which Performance Shares awarded for
such Cycle are earned, on the basis of such criteria and to accomplish such
objectives as the Committee may from time to time select. During any Cycle, the
Committee may adjust the performance goals for such Cycle as it deems equitable
in recognition of unusual or non-recurring events affecting the Company, changes
in applicable tax laws or accounting principles, or such other factors as the
Committee may determine.

     (c)  As soon as practicable after the end of a Performance Cycle, the
Committee shall determine the number of Performance Shares that have been earned
on the basis of performance in relation to the established performance goals.
The payment values of earned Performance Shares shall be distributed to the
Participant or, if the Participant has died, to the Participant's 



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Designated Beneficiary, as soon as practicable thereafter. The Committee shall
determine, at or after the time of award, whether payment values will be settled
in whole or in part in cash or other property, including Common Stock or Awards.

Section 9. RESTRICTED STOCK

     (a)  Subject to the provisions of the Plan, the Committee may award shares
of Restricted Stock and determine the duration of the Restricted Period during
which, and the conditions under which, the shares may be forfeited to the
Company and the other terms and conditions of such Awards. Shares of Restricted
Stock shall be issued for no cash consideration or such minimum consideration as
may be required by applicable law.

     (b)  Shares of Restricted Stock may not be sold, assigned, transferred,
pledged or otherwise encumbered, except as permitted by the Committee, during
the Restricted Period. Shares of Restricted Stock shall be evidenced in such
manner as the Committee may determine. Any certificates issued in respect of
shares of Restricted Stock shall be registered in the name of the Participant
and unless otherwise determined by the Committee, deposited by the Participant,
together with a stock power endorsed in blank, with the Company. At the
expiration of the Restricted Period, the Company shall deliver such certificates
to the Participant or if the Participant has died, to the Participant's
Designated Beneficiary.

Section 10. STOCK UNITS

     (a)  Subject to the provisions of the Plan, the Committee may award Stock
Units subject to such terms, restrictions, conditions, performance criteria,
vesting requirements and payment rules as the Committee shall determine.

     (b)  Shares of Common Stock awarded in connection with a Stock Unit Award
shall be issued for no cash consideration or such minimum consideration as may
be required by applicable law.

Section 11. OTHER STOCK-BASED AWARDS

     (a)  Subject to the provisions of the Plan, the Committee may make other
awards of Common Stock and other awards that are valued in whole or in part by
reference to, or are otherwise based on, Common Stock, including without
limitation convertible preferred stock, convertible debentures, exchangeable
securities and Common Stock awards or options. Other Stock-Based Awards may be
granted either alone or in tandem with other Awards granted under the Plan
and/or cash awards made outside of the Plan.

     (b)  The Committee may establish performance goals, which may be based on
performance goals related to book value, subsidiary performance or such other
criteria as the Committee may determine, Restricted Periods, Performance Cycles,
conversion prices, maturities and security, if any, for any Other Stock-Based
Award. Other Stock-Based Awards may be sold to Participants at the face value
thereof or any discount therefrom or awarded for no consideration or such
minimum consideration as may be required by applicable law.

Section 12. GENERAL PROVISIONS APPLICABLE TO AWARDS

     (a)  Reporting Person Limitations. Notwithstanding any other provision of
the Plan, to the extent required to qualify for the exemption provided by Rule
16b-3 under the Securities Exchange Act of 1934 and any successor provision,
Awards made to a Reporting Person shall 



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not be transferable by such person other than by will or the laws of descent and
distribution or pursuant to a qualified domestic relations order, as defined in
the Code or Title I of the Employee Retirement Income Security Act, or the rules
thereunder.

     (b)  Documentation. Each Award under the Plan shall be evidenced by a
writing delivered to the Participant specifying the terms and conditions thereof
and containing such other terms and conditions not inconsistent with the
provisions of the Plan as the Committee considers necessary or advisable to
achieve the purposes of the Plan or comply with applicable tax and regulatory
laws and accounting principles.

     (c)  Committee Discretion. Each type of Award may be made alone, in
addition to or in relation to any other type of Award. The terms of each type of
Award need not be identical, and the Committee need not treat Participants
uniformly. Except as otherwise provided by the Plan or a particular Award, any
determination with respect to an Award may be made by the Committee at the time
of award or at any time thereafter.

     (d)  Settlement. The Committee shall determine whether Awards are settled
in whole or in part in cash, Common Stock, other securities of the Company,
Awards or other property. The Committee may permit a Participant to defer all or
any portion of a payment under the Plan, including the crediting of interest on
deferred amounts denominated in cash and dividend equivalents on amounts
denominated in Common Stock.

     (e)  Dividends and Cash Awards. In the discretion of the Committee, any
Award under the Plan may provide the Participant with (i) dividends or dividend
equivalents payable currently or deferred with or without interest, and (ii)
cash payments in lieu of or in addition to an Award.

     (f)  Termination of Employment. The Committee shall determine the effect on
an Award of the disability, death, retirement or other termination of employment
of a Participant and the extent to which, and the period during which, the
Participant's legal representative, guardian or Designated Beneficiary may
receive payment of an Award or exercise rights thereunder.

     (g)  Change in Control. In order to preserve a Participant's rights under
an Award in the event of a change in control of the Company, the Committee in
its discretion may, at the time an Award is made or at any time thereafter, take
one or more of the following actions: (i) provide for the acceleration of any
time period relating to the exercise or realization of the Award, (ii) provide
for the purchase of the Award upon the Participant's request for an amount of
cash or other property that could have been received upon the exercise or
realization of the Award had the Award been currently exercisable or payable,
(iii) adjust the terms of the Award in a manner determined by the Committee to
reflect the change in control, (iv) cause the Award to be assumed, or new rights
substituted therefor, by another entity, or (v) make such other provision as the
Committee may consider equitable and in the best interests of the Company.

     (h)  Loans. The Committee may authorize the making of loans or cash
payments to Participants in connection with any Award under the Plan, which
loans may be secured by any security, including Common Stock, underlying or
related to such Award (provided that such Loan shall not exceed the Fair Market
Value of the security subject to such Award), and which may be forgiven upon
such terms and conditions as the Committee may establish at the time of such
loan or at any time thereafter.



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     (i)  Withholding. The Participant shall pay to the Company, or make
provision satisfactory to the Committee for payment of, any taxes required by
law to be withheld in respect of Awards under the Plan no later than the date of
the event creating the tax liability. In the Committee's discretion, such tax
obligations may be paid in whole or in part in shares of Common Stock, including
shares retained from the Award creating the tax obligation, valued at their Fair
Market Value on the date of delivery. The Company and its Affiliates may, to the
extent permitted by law, deduct any such tax obligations from any payment of any
kind otherwise due to the Participant.

     (j)  Foreign Nationals. Awards may be made to Participants who are foreign
nationals or employed outside the United States on such terms and conditions
different from those specified in the Plan as the Committee considers necessary
or advisable to achieve the purposes of the Plan or comply with applicable laws.

     (k)  Amendment of Award. The Committee may amend, modify or terminate any
outstanding Award, including substituting therefor another Award of the same or
a different type, changing the date of exercise or realization and converting an
Incentive Stock Option to a Nonstatutory Stock Option, provided that the
Participant's consent to such action shall be required unless the Committee
determines that the action, taking into account any related action, would not
materially and adversely affect the Participant.

Section 13. MISCELLANEOUS

     (a)  No Right To Employment. No person shall have any claim or right to be
granted an Award, and the grant of an Award shall not be construed as giving a
Participant the right to continued employment. The Company expressly reserves
the right at any time to dismiss a Participant free from any liability or claim
under the Plan, except as expressly provided in the applicable Award.

     (b)  No Rights As Shareholder. Subject to the provisions of the applicable
Award, no Participant or Designated Beneficiary shall have any rights as a
shareholder with respect to any shares of Common Stock to be distributed under
the Plan until he or she becomes the holder thereof. A Participant to whom
Common Stock is awarded shall be considered the holder of the Stock at the time
of the Award except as otherwise provided in the applicable Award.

     (c)  Effective Date. Subject to the approval of the shareholders of the
Company, the Plan shall be effective on the Effective Date. Prior to such
approval, Awards may be made under the Plan expressly subject to such approval.

     (d)  Amendment of Plan. The Board may amend, suspend or terminate the Plan
or any portion thereof at any time, subject to any shareholder approval that the
Board determines to be necessary or advisable.

     (e)  Governing Law. The provisions of the Plan shall be governed by and
interpreted in accordance with the laws of Delaware.



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