**Exhibit 10.1**

**SEPRACOR INC.**

**2000 STOCKINCENTIVE PLAN**

1.                 *Purpose*

Thepurpose of this 2000 Stock Incentive Plan (the “Plan”) of Sepracor Inc., aDelaware****corporation (the “Company”), is toadvance the interests of the Company’s stockholders by enhancing the Company’sability to attract, retain and motivate persons who make (or are expected tomake) important contributions to the Company by providing such persons withequity ownership opportunities and performance-based incentives and therebybetter aligning the interests of such persons with those of the Company’sstockholders. Except where the context otherwise requires, the term “Company”shall include any of the Company’s present or future subsidiary corporations asdefined in Section 424(f) of the Internal Revenue Code of 1986, asamended, and any regulations promulgated thereunder (the “Code”) and any otherbusiness venture (including, without limitation, joint venture or limitedliability company) in which the Company has a significant interest, as determinedby the Board of Directors of the Company (the “Board”).

2.                 *Eligibility*

All ofthe Company’s employees, officers, directors, consultants and advisors (and anyindividuals who have accepted an offer for employment) are eligible to begranted options, restricted stock awards, or other stock-based awards (each, an“Award”) under the Plan. Each person who has been granted an Award under thePlan shall be deemed a “Participant”.

3.                 *Administration, Delegation*

(a)   *Administration by Board of Directors*.   ThePlan will be administered by the Board. The Board shall have authority to grantAwards and to adopt, amend and repeal such administrative rules, guidelines andpractices relating to the Plan as it shall deem advisable. The Board maycorrect any defect, supply any omission or reconcile any inconsistency in thePlan or any Award in the manner and to the extent it shall deem expedient tocarry the Plan into effect and it shall be the sole and final judge of suchexpediency. All decisions by the Board shall be made in the Board’s solediscretion and shall be final and binding on all persons having or claiming anyinterest in the Plan or in any Award. No director or person acting pursuant tothe authority delegated by the Board shall be liable for any action ordetermination relating to or under the Plan made in good faith.

(b)   *Appointment of Committees*.   Tothe extent permitted by applicable law, the Board may delegate any or all ofits powers under the Plan to one or more committees or subcommittees of the Board(a “Committee”). All references in the Plan to the “Board” shall mean theBoard or a Committee of the Board referred to in Section 3(b) to theextent that the Board’s powers or authority under the Plan have been delegatedto such Committee.

4.                 *Stock Available for Awards*

(a)   *Number of Shares*.   Subjectto adjustment under Section 8, Awards may be made under the Plan for up to2,500,000 shares of common stock, $.10 par value per share, of the Company (the“Common Stock”). If any Award expires or is terminated, surrendered or canceledwithout having been fully exercised or is forfeited in whole or in part orresults in any Common Stock not being issued, the unused Common Stock coveredby such Award shall again be available for the grant of Awards under the Plan,subject, however, in the case of Incentive Stock Options (as hereinafterdefined), to any limitation required under the Code. Shares issued under thePlan may consist in whole or in part of authorized but unissued shares ortreasury shares.

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(b)   *Per-Participant Limit*.   Subjectto adjustment under Section 8, for Awards granted after the Common Stockis registered under the Securities Exchange Act of 1934 (the “Exchange Act”),the maximum number of shares of Common Stock with respect to which Awards maybe granted to any Participant under the Plan shall be****500,000per calendar year. The per-Participant limit described in this Section 4(b) shallbe construed and applied consistently with Section 162(m) of the Code(“Section 162(m)”).

5.                 *Stock Options*

(a)   *General*.   The Board maygrant options to purchase Common Stock (each, an “Option”) and determine thenumber of shares of Common Stock to be covered by each Option, the exerciseprice of each Option and the conditions and limitations applicable to theexercise of each Option, including conditions relating to applicable federal orstate securities laws, as it considers necessary or advisable. An Option whichis not intended to be an Incentive Stock Option (as hereinafter defined) shallbe designated a “Nonstatutory Stock Option”.

(b)   *Incentive Stock Options*.   AnOption that the Board intends to be an “incentive stock option” as defined in Section 422of the Code (an “Incentive Stock Option”) shall only be granted to employees ofthe Company and shall be subject to and shall be construed consistently withthe requirements of Section 422 of the Code. The Company shall have noliability to a Participant, or any other party, if an Option (or any partthereof) which is intended to be an Incentive Stock Option is not an IncentiveStock Option.

(c)   *Exercise Price*.   The Boardshall establish the exercise price at the time each Option is granted andspecify it in the applicable option agreement, provided, however, that theexercise price shall not be less than 100% of the fair market value of theCommon Stock, as determined by the Board, at the time the Option is granted.

(d)   *Duration of Options*.   EachOption shall be exercisable at such times and subject to such terms andconditions as the Board may specify in the applicable option agreement,provided however, that no Option will be granted for a term in excess of tenyears.

(e)   *Exercise of Option*.   Optionsmay be exercised by delivery to the Company of a written notice of exercisesigned by the proper person or by any other form of notice (includingelectronic notice) approved by the Board together with payment in full asspecified in Section 5(f) for the number of shares for which theOption is exercised.

(f)    *Payment Upon Exercise.  *CommonStock purchased upon the exercise of an Option granted under the Plan shall bepaid for as follows:

(1)   in cash or by check, payable to the order of the Company;

(2)   except as the Board may, in its sole discretion, otherwise providein an option agreement, by (i) delivery of an irrevocable andunconditional undertaking by a creditworthy broker to deliver promptly to theCompany sufficient funds to pay the exercise price or (ii) delivery by theParticipant to the Company of a copy of irrevocable and unconditionalinstructions to a creditworthy broker to deliver promptly to the Company cashor a check sufficient to pay the exercise price;

(3)   when the Common Stock is registered under the Exchange Act, bydelivery of shares of Common Stock owned by the Participant valued at theirfair market value as determined by (or in a manner approved by) the Board ingood faith (“Fair Market Value”), provided (i) such method of payment isthen permitted under applicable law and (ii) such Common Stock was ownedby the Participant at least six months prior to such delivery;

(4)   to the extent permitted by the Board, in its sole discretion by (i) deliveryof a promissory note of the Participant to the Company on terms determined bythe Board, or (ii) payment of such other lawful consideration as the Boardmay determine; or

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(5)   by any combination of the above permitted forms of payment.

(g)   *Substitute Options*.   Inconnection with a merger or consolidation of an entity with the Company or theacquisition by the Company of property or stock of an entity, the Board maygrant Options in substitution for any options or other stock or stock-basedawards granted by such entity or an affiliate thereof. Substitute Options maybe granted on such terms as the Board deems appropriate in the circumstances,notwithstanding any limitations on Options contained in the other sections ofthis Section 5.

6.                 *Restricted Stock*

(a)   *Grants*.   The Board may grantAwards entitling recipients to acquire shares of Common Stock, subject to theright of the Company to repurchase all or part of such shares at their issueprice or other stated or formula price (or to require forfeiture of such sharesif issued at no cost) from the recipient in the event that conditions specifiedby the Board in the applicable Award are not satisfied prior to the end of theapplicable restriction period or periods established by the Board for suchAward (each, a “Restricted Stock Award”).

(b)   *Terms and Conditions*.   TheBoard shall determine the terms and conditions of any such Restricted StockAward, including the conditions for repurchase (or forfeiture) and the issueprice, if any. Any stock certificates issued in respect of a Restricted StockAward shall be registered in the name of the Participant and, unless otherwisedetermined by the Board, deposited by the Participant, together with a stockpower endorsed in blank, with the Company (or its designee). At the expirationof the applicable restriction periods, the Company (or such designee) shalldeliver the certificates no longer subject to such restrictions to theParticipant or if the Participant has died, to the beneficiary designated, in amanner determined by the Board, by a Participant to receive amounts due orexercise rights of the Participant in the event of the Participant’s death (the“Designated Beneficiary”). In the absence of an effective designation by aParticipant, Designated Beneficiary shall mean the Participant’s estate.

7.                 *Other Stock-Based Awards*

TheBoard shall have the right to grant other Awards based upon the Common Stockhaving such terms and conditions as the Board may determine, including thegrant of shares based upon certain conditions, the grant of securitiesconvertible into Common Stock and the grant of stock appreciation rights.

8.                 *Adjustments for Changes in Common Stock and Certain Other Events*

(a)   *Changes in Capitalization*.   Inthe event of any stock split, reverse stock split, stock dividend,recapitalization, combination of shares, reclassification of shares, spin-offor other similar change in capitalization or event, or any distribution toholders of Common Stock other than a normal cash dividend, (i) the numberand class of securities available under this Plan, (ii) the per-Participantlimit set forth in Section 4(b), (iii) the number and class ofsecurities and exercise price per share subject to each outstanding Option, (iv) therepurchase price per share subject to each outstanding Restricted Stock Award,and (v) the terms of each other outstanding Award shall be appropriatelyadjusted by the Company (or substituted Awards may be made, if applicable) tothe extent the Board shall determine, in good faith, that such an adjustment(or substitution) is necessary and appropriate. If this Section 8(a) appliesand Section 8(c) also applies to any event, Section 8(c) shallbe applicable to such event, and this Section 8(a) shall not beapplicable.

(b)   *Liquidation or Dissolution*.   Inthe event of a proposed liquidation or dissolution of the Company, the Boardshall upon written notice to the Participants provide that all then unexercisedOptions will (i) become exercisable in full as of a specified time atleast 10 business days prior to the effective date of such liquidation ordissolution and (ii) terminate effective upon such liquidation ordissolution, except to the extent exercised before such effective date. TheBoard may specify the effect of a 

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liquidation ordissolution on any Restricted Stock Award or other Award granted under the Planat the time of the grant of such Award.

(c)   *Acquisition and Change in Control Events*

(1)          *Definitions*

(a)           An“Acquisition Event” shall mean:

(i)            anymerger or consolidation of the Company with or into another entity as a resultof which the Common Stock is converted into or exchanged for the right toreceive cash, securities or other property; or

(ii)        anyexchange of shares of the Company for cash, securities or other propertypursuant to a statutory share exchange transaction.

(b)          A“Change in Control Event” shall mean:

(i)            theacquisition by an individual, entity or group (within the meaning ofSection 13(d)(3) or 14(d)(2) of the Securities Exchange Act of1934, as amended (the “Exchange Act”)) (a “Person”) of beneficial ownership ofany capital stock of the Company if, after such acquisition, such Personbeneficially owns (within the meaning of Rule 13d-3 promulgatedunder the Exchange Act) 30% or more of either (x) the then-outstandingshares of common stock of the Company (the “Outstanding Company Common Stock”)or (y) the combined voting power of the then-outstanding securities of theCompany entitled to vote generally in the election of directors (the“Outstanding Company Voting Securities”); *provided, however*,that for purposes of this subsection (i), the following acquisitions shall notconstitute a Change in Control Event: (A) any acquisition directly fromthe Company (excluding an acquisition pursuant to the exercise, conversion orexchange of any security exercisable for, convertible into or exchangeable forcommon stock or voting securities of the Company, unless the Person exercising,converting or exchanging such security acquired such security directly from theCompany or an underwriter or agent of the Company), (B) any acquisition byany employee benefit plan (or related trust) sponsored or maintained by theCompany or any corporation controlled by the Company, or (C) anyacquisition by any corporation pursuant to a Business Combination (as definedbelow) which complies with clauses (x) and (y)  of subsection(iii) of this definition; or

(ii)        such time as theContinuing Directors (as defined below) do not constitute a majority of theBoard (or, if applicable, the Board of Directors of a successor corporation tothe Company), where the term “Continuing Director” means at any date a memberof the  Board (x) who was a memberof the Board on the date of the initial adoption of this Plan by the Board or(y) who was nominated or elected subsequent to such date by at least amajority of the directors who were Continuing Directors at the time of suchnomination or election or whose election to the Board was recommended orendorsed by at least a majority of the directors who were Continuing Directorsat the time of such nomination or election; *provided*, *however*, that there shall be excluded from this clause(y) any individual whose initial assumption of office occurred as a resultof an actual or threatened election contest with respect to the election orremoval of directors or other actual or threatened solicitation of proxies orconsents, by or on behalf of a person other than the Board; or

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(iii)    the consummation of a merger,consolidation, reorganization, recapitalization or statutory share exchangeinvolving the Company or a sale or other disposition of all or substantiallyall of the assets of the Company (a “Business Combination”), unless,immediately following such Business Combination, each of the following twoconditions is satisfied: (x) all or substantially all of the individualsand entities who were the beneficial owners of the Outstanding Company CommonStock and Outstanding Company Voting Securities immediately prior to suchBusiness Combination beneficially own, directly or indirectly, more than 50% ofthe then-outstanding shares of common stock and the combined voting power ofthe then-outstanding securities entitled to vote generally in the election ofdirectors, respectively, of the resulting or acquiring corporation in suchBusiness Combination (which shall include, without limitation, a corporationwhich as a result of such transaction owns the Company or substantially all of theCompany’s assets either directly or through one or more subsidiaries) (suchresulting or acquiring corporation is referred to herein as the “AcquiringCorporation”) in substantially the same proportions as their ownership of theOutstanding Company Common Stock and Outstanding Company Voting Securities,respectively, immediately prior to such Business Combination and (y) noPerson (excluding the Acquiring Corporation or any employee benefit plan (orrelated trust) maintained or sponsored by the Company or by the AcquiringCorporation) beneficially owns, directly or indirectly, 30% or more of thethen-outstanding shares of common stock of the Acquiring Corporation, or of thecombined voting power of the then-outstanding securities of such corporation entitledto vote generally in the election of directors (except to the extent that suchownership existed prior to the Business Combination).

(2)          *Effect onOptions*

(a)           *AcquisitionEvent*.   Upon the occurrence of an Acquisition Event (regardlessof whether such event also constitutes a Change in Control Event), or theexecution by the Company of any agreement with respect to an Acquisition Event(regardless of whether such event will result in a Change in Control Event),the Board shall provide that all outstanding Options shall be assumed, orequivalent options shall be substituted, by the acquiring or succeedingcorporation (or an affiliate thereof); *provided**that* if such Acquisition Event also constitutes a Change inControl Event, except to the extent specifically provided to the contrary inthe instrument evidencing any Option or any other agreement between aParticipant and the Company, such assumed or substituted options shall be immediatelyexercisable in full upon the occurrence of such Acquisition Event. For purposeshereof, an Option shall be considered to be assumed if, following consummationof the Acquisition Event, the Option confers the right to purchase, for eachshare of Common Stock subject to the Option immediately prior to theconsummation of the Acquisition Event, the consideration (whether cash,securities or other property) received as a result of the Acquisition Event byholders of Common Stock for each share of Common Stock held immediately priorto the consummation of the Acquisition Event (and if holders were offered achoice of consideration, the type of consideration chosen by the holders of amajority of the outstanding shares of Common Stock); provided, however, that ifthe consideration received as a result of the Acquisition Event is not solelycommon stock of the acquiring or succeeding corporation (or an affiliatethereof), the Company may, with the consent of the acquiring or succeedingcorporation, provide for the consideration to be received upon the exercise ofOptions to consist solely of common stock of the acquiring or succeeding 

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corporation (or anaffiliate thereof) equivalent in fair market value to the per shareconsideration received by holders of outstanding shares of Common Stock as aresult of the Acquisition Event.

Notwithstanding the foregoing, if the acquiring orsucceeding corporation (or an affiliate thereof) does not agree to assume, orsubstitute for, such Options, then the Board shall, upon written notice to theParticipants, provide that all then unexercised Options will become exercisablein full as of a specified time prior to the Acquisition Event and willterminate immediately prior to the consummation of such Acquisition Event,except to the extent exercised by the Participants before the consummation ofsuch Acquisition Event; provided, however, in the event of an Acquisition Eventunder the terms of which holders of Common Stock will receive upon consummationthereof a cash payment for each share of Common Stock surrendered pursuant tosuch Acquisition Event (the “Acquisition Price”), then the Board may insteadprovide that all outstanding Options shall terminate upon consummation of suchAcquisition Event and that each Participant shall receive, in exchangetherefor, a cash payment equal to the amount (if any) by which (A) theAcquisition Price multiplied by the number of shares of Common Stock subject tosuch outstanding Options (whether or not then exercisable), exceeds (B) theaggregate exercise price of such Options.

(b)          *Change inControl Event that is not an Acquisition Event*.   Upon theoccurrence of a Change in Control Event that does not also constitute anAcquisition Event, except to the extent specifically provided to the contraryin the instrument evidencing any Option or any other agreement between aParticipant and the Company, all Options then-outstanding shall automaticallybecome immediately exercisable in full.

(3)          *Effect onRestricted Stock Awards*

(a)           *AcquisitionEvent that is not a Change in Control Event*.   Upon theoccurrence of an Acquisition Event that is not a Change in Control Event, therepurchase and other rights of the Company under each outstanding RestrictedStock Award shall inure to the benefit of the Company’s successor and shallapply to the cash, securities or other property which the Common Stock wasconverted into or exchanged for pursuant to such Acquisition Event in the samemanner and to the same extent as they applied to the Common Stock subject tosuch Restricted Stock Award.

(b)          *Change inControl Event*.   Upon the occurrence of a Change in ControlEvent (regardless of whether such event also constitutes an Acquisition Event),except to the extent specifically provided to the contrary in the instrumentevidencing any Restricted Stock Award or any other agreement between aParticipant and the Company, all restrictions and conditions on all RestrictedStock Awards then-outstanding shall automatically be deemed terminated orsatisfied.

(4)          *Effect onOther Awards*

(a)           *AcquisitionEvent that is not a Change in Control Event*.   The Board shallspecify the effect of an Acquisition Event that is not a Change in ControlEvent on any other Award granted under the Plan at the time of the grant ofsuch Award.

(b)          *Change inControl Event*.   Upon the occurrence of a Change in Control Event(regardless of whether such event also constitutes an Acquisition Event),except to the extent specifically provided to the contrary in the instrumentevidencing any other Award or any other agreement between a Participant and theCompany, all other 

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Awards shall becomeexercisable, realizable or vested in full, or shall be free of all conditionsor restrictions, as applicable to each such Award.

(5)          *Limitations*.   Notwithstanding the foregoing provisionsof this Section 8(c), if the Change in Control Event is intended to beaccounted for as a “pooling of interests” for financial accounting purposes,and if the acceleration to be effected by the foregoing provisions of this Section 8(c) wouldpreclude accounting for the Change in Control Event as a “pooling of interests”for financial accounting purposes, then no such acceleration shall occur uponthe Change in Control Event.

9.                 *General Provisions Applicable to Awards*

(a)   *Transferability of Awards*.   Except as the Board mayotherwise determine or provide in an Award, Awards shall not be sold, assigned,transferred, pledged or otherwise encumbered by the person to whom they aregranted, either voluntarily or by operation of law, except by will or the lawsof descent and distribution, and, during the life of the Participant, shall beexercisable only by the Participant. References to a Participant, to the extentrelevant in the context, shall include references to authorized transferees.

(b)   *Documentation*.   Each Award shall be evidenced by awritten instrument in such form as the Board shall determine. Each Award maycontain terms and conditions in addition to those set forth in the Plan.

(c)   *Board Discretion*.   Except as otherwise provided by thePlan, each Award may be made alone or in addition or in relation to any otherAward. The terms of each Award need not be identical, and the Board need nottreat Participants uniformly.

(d)   *Termination of Status*.   The Board shall determine theeffect on an Award of the disability, death, retirement, authorized leave ofabsence or other change in the employment or other status of a Participant andthe extent to which, and the period during which, the Participant, theParticipant’s legal representative, conservator, guardian or DesignatedBeneficiary may exercise rights under the Award.

(e)   *Withholding*.   Each Participant shall pay to theCompany, or make provision satisfactory to the Board for payment of, any taxesrequired by law to be withheld in connection with Awards to such Participant nolater than the date of the event creating the tax liability. Except as theBoard may otherwise provide in an Award, when the Common Stock is registeredunder the Exchange Act, Participants may, to the extent then permitted underapplicable law, satisfy such tax obligations in whole or in part by delivery ofshares of Common Stock, including shares retained from the Award creating thetax obligation, valued at their Fair Market Value. The Company may, to theextent permitted by law, deduct any such tax obligations from any payment ofany kind otherwise due to a Participant.

(f)    *Amendment of Award*.   The Board may amend, modify orterminate any outstanding Award, including but not limited to, substitutingtherefor another Award of the same or a different type, changing the date ofexercise or realization, and converting an Incentive Stock Option to aNonstatutory Stock Option, provided that the Participant’s consent to suchaction shall be required unless the Board determines that the action, takinginto account any related action, would not materially and adversely affect theParticipant.

(g)   *Conditions on Delivery of Stock*.   The Company will notbe obligated to deliver any shares of Common Stock pursuant to the Plan or toremove restrictions from shares previously delivered under the Plan until (i) allconditions of the Award have been met or removed to the satisfaction of theCompany, (ii) in the opinion of the Company’s counsel, all other legalmatters in connection with the issuance and delivery of such shares have beensatisfied, including any applicable securities laws and any applicable stockexchange or stock market rules and regulations, and (iii) theParticipant has executed and delivered 

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to the Company suchrepresentations or agreements as the Company may consider appropriate tosatisfy the requirements of any applicable laws, rules or regulations.

(h)   *Acceleration*.   The Board mayat any time provide that any Options shall become immediately exercisable infull or in part, that any Restricted Stock Awards shall be free of restrictionsin full or in part or that any other Awards may become exercisable in full orin part or free of some or all restrictions or conditions, or otherwiserealizable in full or in part, as the case may be.

10.          *Miscellaneous*

(a)   *No Right To Employment or Other Status*.   No personshall have any claim or right to be granted an Award, and the grant of an Awardshall not be construed as giving a Participant the right to continuedemployment or any other relationship with the Company. The Company expresslyreserves the right at any time to dismiss or otherwise terminate itsrelationship with a Participant free from any liability or claim under thePlan, except as expressly provided in the applicable Award.

(b)   *No Rights As Stockholder*.   Subject to the provisions ofthe applicable Award, no Participant or Designated Beneficiary shall have anyrights as a stockholder with respect to any shares of Common Stock to bedistributed with respect to an Award until becoming the record holder of suchshares. Notwithstanding the foregoing, in the event the Company effects a splitof the Common Stock by means of a stock dividend and the exercise price of andthe number of shares subject to such Option are adjusted as of the date of thedistribution of the dividend (rather than as of the record date for suchdividend), then an optionee who exercises an Option between the record date andthe distribution date for such stock dividend shall be entitled to receive, onthe distribution date, the stock dividend with respect to the shares of CommonStock acquired upon such Option exercise, notwithstanding the fact that such shareswere not outstanding as of the close of business on the record date for suchstock dividend.

(c)   *Effective Date and Term of Plan*.   The Plan shall becomeeffective on the date on which it is adopted by the Board, but no Award grantedto a Participant that is intended to comply with Section 162(m) shallbecome exercisable, vested or realizable, as applicable to such Award, unlessand until the Plan has been approved by the Company’s stockholders to theextent stockholder approval is required by Section 162(m) in themanner required under Section 162(m) (including the vote requiredunder Section 162(m)). No Awards shall be granted under the Plan after thecompletion of ten years from the earlier of (i) the date on which the Planwas adopted by the Board or (ii) the date the Plan was approved by theCompany’s stockholders, but Awards previously granted may extend beyond thatdate.

(d)   *Amendment of Plan*.   The Board may amend, suspend orterminate the Plan or any portion thereof at any time, provided that to the extentrequired by Section 162(m), no Award granted to a Participant that isintended to comply with Section 162(m) after the date of suchamendment shall become exercisable, realizable or vested, as applicable to suchAward, unless and until such amendment shall have been approved by the Company’sstockholders as required by Section 162(m) (including the voterequired under Section 162(m)).

(e)   *Governing Law*.   Theprovisions of the Plan and all Awards made hereunder shall be governed by andinterpreted in accordance with the laws of the State of Delaware, withoutregard to any applicable conflicts of law.
|        | Adopted by the Board of Directors on  February 24, 2000 |
|--------|--------------------------------------------------------------|
|   | Adopted by the  Stockholders on May 24, 2000            |

 

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**AMENDMENT NO 1. TO2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”) of Sepracor Inc. be, and hereby is, amended asfollows:

1.     Section 4,paragraph (a) is deleted in its entirety and the following is substitutedin its place:

*“(a)  *Number of Shares.   Subjectto adjustment under Section 8, Awards may be made under the Plan for up to4,000,000 shares of common stock, $.10 par value per share, of the Company (the“Common Stock”). If any Award expires or is terminated, surrendered or cancelledwithout having been fully exercised or is forfeited in whole or in part orresults in any Common Stock not being issued, the unused Common Stock coveredby such Award shall again be available for the grant of Awards under the Plan,subject, however, in the case of Incentive Stock Options (as hereinafterdefined), to any limitation required under the Code. Shares issued under thePlan may consist in whole or in part of authorized but unissued shares ortreasury shares.”
|        | Adopted by the Board of Directors on  February 21, 2002 |
|--------|--------------------------------------------------------------|
|   | Adopted by the  Stockholders on May 22, 2002            |

 

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**AMENDMENT NO 2. TO2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”) of Sepracor Inc. be, and hereby is, amended asfollows:

1.     Section 4,paragraph (a) is deleted in its entirety and the following is substitutedin its place:

*“(a)  *Number of Shares.   Subjectto adjustment under Section 8, Awards may be made under the Plan for up to5,5000,000 shares of common stock, $.10 par value per share, of the Company(the “Common Stock”). If any Award expires or is terminated, surrendered or cancelledwithout having been fully exercised or is forfeited in whole or in part orresults in any Common Stock not being issued, the unused Common Stock coveredby such Award shall again be available for the grant of Awards under the Plan,subject, however, in the case of Incentive Stock Options (as hereinafterdefined), to any limitation required under the Code. Shares issued under thePlan may consist in whole or in part of authorized but unissued shares ortreasury shares.”
|        | Adopted by the Board of Directors on  February 20, 2003 |
|--------|--------------------------------------------------------------|
|   | Adopted by the  Stockholders on May 22, 2003            |

 

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**AMENDMENT NO 3. TO2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”), as amended, of Sepracor Inc. be, and hereby is,further amended as follows:

1.     Section 4,paragraph (a) is deleted in its entirety and the following is substitutedin its place:

“(a)   *Number of Shares*.   Subject to adjustment under Section 8,Awards may be made under the Plan for up to 8,000,000 shares of common stock,$.10 par value per share, of the Company (the “Common Stock”). If any Awardexpires or is terminated, surrendered or cancelled without having been fullyexercised or is forfeited in whole or in part or results in any Common Stocknot being issued, the unused Common Stock covered by such Award shall again beavailable for the grant of Awards under the Plan, subject, however, in the caseof Incentive Stock Options (as hereinafter defined), to any limitation requiredunder the Code. Shares issued under the Plan may consist in whole or in part ofauthorized but unissued shares or treasury shares.”
|        | Adopted by the Board of Directors on  February 11, 2004. |
|--------|---------------------------------------------------------------|
|   | Adopted by the  Stockholders on May 19, 2004.            |

 

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**AMENDMENT NO. 4 TO2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”), as amended, of Sepracor Inc. be, and hereby is,further amended as follows:

1.     Section 4,paragraph (a) is deleted in its entirety and the following is substitutedin its place:

“(a)   *Number of Shares*.   Subject to adjustment under Section 8,Awards may be made under the Plan for up to 9,500,000 shares of common stock,$.10 par value per share, of the Company (the “Common Stock”). If any Awardexpires or is terminated, surrendered or cancelled without having been fullyexercised or is forfeited in whole or in part or results in any Common Stocknot being issued, the unused Common Stock covered by such Award shall again beavailable for the grant of Awards under the Plan, subject, however, in the caseof Incentive Stock Options (as hereinafter defined), to any limitation requiredunder the Code. Shares issued under the Plan may consist in whole or in part ofauthorized but unissued shares or treasury shares.”
|        | Adopted by the Board of Directors on  April 1, 2005. |
|--------|-----------------------------------------------------------|
|   | Adopted by the  Stockholders on May 19, 2005.        |

 

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**AMENDMENT NO. 5 TO 2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”) of Sepracor Inc. be and hereby is, amended asfollows:

1.     The following Section 5(h) is hereby added:

(h)   *Limitation on Repricing*.   Unlesssuch action is approved by the Company’s stockholders: (i) no outstandingOption granted under the Plan may be amended to provide an exercise price pershare that is lower than the then-current exercise price per share of suchoutstanding Option (other than adjustments pursuant to Section 8), and (ii) theBoard may not cancel any outstanding option (whether or not granted under thePlan) and grant in substitution therefor new Awards under the Plan covering thesame or a different number of shares of Common Stock and having an exerciseprice per share lower than the then-current exercise price per share of thecancelled Option.

2.     Section 9(f) ishereby deleted in its entirety and replaced with the following:

(f)   *Amendment of Plan*.   Except as prohibited by Section 5(h),the Board may amend, modify or terminate any outstanding Award, including butnot limited to, substituting therefore another Award of the same or a differenttype, changing the date of exercise or realization, and converting an IncentiveStock Option to a Non-Statutory Stock Option, provided that the Participant’sconsent to such action shall be required unless the Board determines that theaction, taking into account any related action, would not materially andadversely affect the Participant.

|  | Adopted by the  Board of Directors on May 13, 2005 |
|--|---------------------------------------------------------|

 

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**AMENDMENT NO. 6 TO 2000 STOCK INCENTIVE PLANOFSEPRACOR INC.**

The 2000 StockIncentive Plan (the “Plan”) of Sepracor Inc. be and hereby is, amended asfollows:

1.     Section 4,paragraph (a) is deleted in its entirety and the following is substitutedin its place:

“(a)   *Number of Shares*.   Subjectto adjustment under Section 8, Awards may be made under the Plan for up to11,500,000 shares of common stock, $.10 par value per share, of the Company(the “Common Stock”). If any Award expires or is terminated, surrendered or cancelledwithout having been fully exercised or is forfeited in whole or in part orresults in any Common Stock not being issued, the unused Common Stock coveredby such Award shall again be available for the grant of Awards under the Plan,subject, however, in the case of Incentive Stock Options (as hereinafterdefined), to any limitation required under the Code. Shares issued under thePlan may consist in whole or in part of authorized but unissued shares ortreasury shares.”

|   | Adopted by the Board of Directors on  April 5, 2006. |
|--------|-----------------------------------------------------------|
|   | Adopted by the  Stockholders on May 18, 2006.        |

 

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