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                                                                   EXHIBIT 10.1

                                   DYAX CORP.

                 AMENDED AND RESTATED 1995 EQUITY INCENTIVE PLAN

Section 1. PURPOSE

         The purpose of the Dyax Corp. 1995 Equity Incentive Plan (the "Plan")
is to attract and retain key employees and directors and consultants of the
Company and its Affiliates, to provide an incentive for them to assist the
Company 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 the Compensation Committee of the Board or such other
committee of the Board appointed by the Board to administer the Plan or a
specified portion thereof; provided, however, that in any instance the Board of
Directors may take away any action delegated to the Committee hereunder. If a
Committee is authorized to grant Awards to a Reporting Person or a "covered
employee" within the meaning of Section 162(m) of the Code, each member shall be
a "Non-Employee Director" or the equivalent within the meaning of Rule 16b-3
under the Exchange Act or an "outside director" or the equivalent within the
meaning of Section 162(m) of the Code, respectively.

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

         "Company" means Dyax Corp. (formerly named Biotage, 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.

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         "Effective Date" means July 13, 1995.

         "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 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 selected by the Committee
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.

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Section 3. ADMINISTRATION

         The Plan shall be administered by the Committee; provided, however,
that in any instance the Board of Directors may take any action delegated
hereunder to the Committee. 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 or covered employees and
all determinations under the Plan with respect thereto, provided that the
Committee shall fix the maximum amount of such Awards for all such Participants
and a maximum for any one Participant.

Section 4. ELIGIBILITY

         All employees and, in the case of Awards other than Incentive Stock
Options, directors and consultants of the Company or any Affiliate, capable of
contributing significantly to the successful performance of the Company, other
than a person who has 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 (b), and after giving effect
to the 0.652-for-one reverse stock split of the Company's Common Stock affected
in March 1998, Awards may be made under the Plan for up to Five Million Five
Hundred Thousand (5,500,000) shares of Common Stock, which number includes
shares previously issued upon exercise of options granted under the Plan. In no
event shall the number of shares of Common Stock that may be subject to Awards
for any individual exceed 489,000 shares of Common Stock in the aggregate except
to the extent of any adjustment under subsection (b). If any Award in respect of
shares of Common Stock expires or is terminated unexercised or is forfeited, 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) In the event that the Committee 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

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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. See subsection (b) below. 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 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, or by
retaining shares otherwise issuable pursuant to the Option, in each case valued
at their Fair Market Value on the date of delivery or retention, 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 or retention of shares to the Company
in payment of an Option, the Participant 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, which SAR can only be exercised upon
or 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

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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 any stock market in which the Common Stock is usually
traded.










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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 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 may 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.

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         (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) 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 to comply with applicable tax and regulatory
laws and accounting principles.

         (b) 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.

         (c) 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.

         (d) 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.

         (e) 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,

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guardian or Designated Beneficiary may receive payment of an Award or exercise
rights thereunder.

         (f) 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 (as defined by
the Committee), 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.

         (g) 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.

         (h) WITHHOLDING TAXES. 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.

         (i) 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 to comply with
applicable laws.

         (j) 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

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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 STOCKHOLDER. Subject to the provisions of the
applicable Award, no Participant or Designated Beneficiary shall have any rights
as a stockholder 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 stockholders of the
Company, the Plan shall be effective on the Effective Date. Before such
approval, Awards may be made under the Plan expressly subject to such approval.

         (d) AMENDMENT OF PLAN. The Committee may amend, suspend or terminate
the Plan or any portion thereof at any time, subject to any stockholder approval
that the Committee 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 the State of Delaware.

                    -----------------------------------------

THIS PLAN WAS APPROVED BY THE BOARD OF DIRECTORS ON JULY 13, 1995.

THIS PLAN WAS APPROVED BY THE STOCKHOLDERS ON AUGUST 8, 1995.

THIS PLAN WAS AMENDED BY THE BOARD OF DIRECTORS ON OCTOBER 17, 1996, AND SUCH
AMENDMENT WAS APPROVED BY THE STOCKHOLDERS EFFECTIVE AS OF OCTOBER 23, 1996.

THIS PLAN WAS FURTHER AMENDED BY THE BOARD OF DIRECTORS ON OCTOBER 22, 1997 AND
ON JANUARY 28, 1998, AND SUCH AMENDMENTS WERE APPROVED BY THE STOCKHOLDERS
EFFECTIVE AS OF MARCH 23, 1998.

THIS PLAN WAS FURTHER AMENDED BY THE BOARD OF DIRECTORS ON AUGUST 13, 1998, AND
SUCH AMENDMENT WAS APPROVED BY THE STOCKHOLDERS EFFECTIVE AS OF AUGUST 28, 1998.

THIS PLAN WAS FURTHER AMENDED BY THE BOARD OF DIRECTORS ON AUGUST 5, 1999, AND
SUCH AMENDMENT WAS APPROVED BY THE STOCKHOLDERS EFFECTIVE AS OF OCTOBER 29,
1999.

THIS PLAN WAS FURTHER AMENDED BY THE BOARD OF DIRECTORS ON MARCH 16, 2000, AND
SUCH AMENDMENT WAS APPROVED BY THE STOCKHOLDERS EFFECTIVE AS OF MARCH 20, 2000.

THIS PLAN WAS FURTHER AMENDED BY THE BOARD OF DIRECTORS ON OCTOBER 26, 2001.


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