Exhibit 10.1

SEPRACOR INC.

2000 STOCK INCENTIVE PLAN

1.                                       PURPOSE

The purpose of this 2000 Stock Incentive Plan (the “Plan”) of Sepracor Inc., a
Delaware corporation (the “Company”), is to advance the interests of the
Company’s stockholders by enhancing the Company’s ability to attract, retain and
motivate persons who make (or are expected to make) important contributions to
the Company by providing such persons with equity ownership opportunities and
performance-based incentives and thereby better aligning the interests of such
persons with those of the Company’s stockholders.  Except where the context
otherwise requires, the term “Company” shall include any of the Company’s
present or future subsidiary corporations as defined in Section 424(f) of the
Internal Revenue Code of 1986, as amended, and any regulations promulgated
thereunder (the “Code”) and any other business venture (including, without
limitation, joint venture or limited liability company) in which the Company has
a significant interest, as determined by the Board of Directors of the Company
(the “Board”).

2.                                       ELIGIBILITY

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

3.                                       ADMINISTRATION, DELEGATION

(A)                                  ADMINISTRATION BY BOARD OF DIRECTORS.  THE
PLAN WILL BE ADMINISTERED BY THE BOARD.  THE BOARD SHALL HAVE AUTHORITY TO GRANT
AWARDS AND TO ADOPT, AMEND AND REPEAL SUCH ADMINISTRATIVE RULES, GUIDELINES AND
PRACTICES RELATING TO THE PLAN AS IT SHALL DEEM ADVISABLE.  THE BOARD MAY
CORRECT ANY DEFECT, SUPPLY ANY OMISSION OR RECONCILE ANY INCONSISTENCY IN THE
PLAN OR ANY AWARD IN THE MANNER AND TO THE EXTENT IT SHALL DEEM EXPEDIENT TO
CARRY THE PLAN INTO EFFECT AND IT SHALL BE THE SOLE AND FINAL JUDGE OF SUCH
EXPEDIENCY.  ALL DECISIONS BY THE BOARD SHALL BE MADE IN THE BOARD’S SOLE
DISCRETION AND SHALL BE FINAL AND BINDING ON ALL PERSONS HAVING OR CLAIMING ANY
INTEREST IN THE PLAN OR IN ANY AWARD.  NO DIRECTOR OR PERSON ACTING PURSUANT TO
THE AUTHORITY DELEGATED BY THE BOARD SHALL BE LIABLE FOR ANY ACTION OR
DETERMINATION RELATING TO OR UNDER THE PLAN MADE IN GOOD FAITH.

(B)                                 APPOINTMENT OF COMMITTEES. TO THE EXTENT
PERMITTED BY APPLICABLE LAW, THE BOARD MAY DELEGATE ANY OR ALL OF ITS 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

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MEAN THE BOARD OR A COMMITTEE OF THE BOARD REFERRED TO IN SECTION 3(B) TO THE
EXTENT THAT THE BOARD’S POWERS OR AUTHORITY UNDER THE PLAN HAVE BEEN DELEGATED
TO SUCH COMMITTEE.

4.                                       STOCK AVAILABLE FOR AWARDS

(A)                                  NUMBER OF SHARES. SUBJECT TO ADJUSTMENT
UNDER SECTION 8, AWARDS MAY BE MADE UNDER THE PLAN FOR UP TO 2,500,000 SHARES OF
COMMON STOCK, $.10 PAR VALUE PER SHARE, OF THE COMPANY (THE “COMMON STOCK”).  IF
ANY AWARD EXPIRES OR IS TERMINATED, SURRENDERED OR CANCELED WITHOUT HAVING BEEN
FULLY EXERCISED OR IS FORFEITED IN WHOLE OR IN PART OR RESULTS IN ANY COMMON
STOCK NOT BEING ISSUED, THE UNUSED COMMON STOCK COVERED BY SUCH AWARD SHALL
AGAIN BE AVAILABLE FOR THE GRANT OF AWARDS UNDER THE PLAN, SUBJECT, HOWEVER, IN
THE CASE OF INCENTIVE STOCK OPTIONS (AS HEREINAFTER DEFINED), TO ANY LIMITATION
REQUIRED UNDER THE CODE.  SHARES ISSUED UNDER THE PLAN MAY CONSIST IN WHOLE OR
IN PART OF AUTHORIZED BUT UNISSUED SHARES OR TREASURY SHARES.

(B)                                 PER-PARTICIPANT LIMIT.  SUBJECT TO
ADJUSTMENT UNDER SECTION 8, FOR AWARDS GRANTED AFTER THE COMMON STOCK IS
REGISTERED UNDER THE SECURITIES EXCHANGE ACT OF 1934 (THE “EXCHANGE ACT”), THE
MAXIMUM NUMBER OF SHARES OF COMMON STOCK WITH RESPECT TO WHICH AWARDS MAY BE
GRANTED TO ANY PARTICIPANT UNDER THE PLAN SHALL BE 500,000 PER CALENDAR YEAR.
THE PER-PARTICIPANT LIMIT DESCRIBED IN THIS SECTION 4(B) SHALL BE CONSTRUED AND
APPLIED CONSISTENTLY WITH SECTION 162(M) OF THE CODE (“SECTION 162(M)”).

5.                                       STOCK OPTIONS

(A)                                  GENERAL.  THE BOARD MAY GRANT OPTIONS TO
PURCHASE COMMON STOCK (EACH, AN “OPTION”) AND DETERMINE THE NUMBER OF SHARES OF
COMMON STOCK TO BE COVERED BY EACH OPTION, THE EXERCISE PRICE OF EACH OPTION AND
THE CONDITIONS AND LIMITATIONS APPLICABLE TO THE EXERCISE OF EACH OPTION,
INCLUDING CONDITIONS RELATING TO APPLICABLE FEDERAL OR STATE SECURITIES LAWS, AS
IT CONSIDERS NECESSARY OR ADVISABLE.  AN OPTION WHICH IS NOT INTENDED TO BE AN
INCENTIVE STOCK OPTION (AS HEREINAFTER DEFINED) SHALL BE DESIGNATED A
“NONSTATUTORY STOCK OPTION”.

(B)                                 INCENTIVE STOCK OPTIONS.  AN OPTION THAT THE
BOARD INTENDS TO BE AN “INCENTIVE STOCK OPTION” AS DEFINED IN SECTION 422 OF THE
CODE (AN “INCENTIVE STOCK OPTION”) SHALL ONLY BE GRANTED TO EMPLOYEES OF THE
COMPANY AND SHALL BE SUBJECT TO AND SHALL BE CONSTRUED CONSISTENTLY WITH THE
REQUIREMENTS OF SECTION 422 OF THE CODE.  THE COMPANY SHALL HAVE NO LIABILITY TO
A PARTICIPANT, OR ANY OTHER PARTY, IF AN OPTION (OR ANY PART THEREOF) WHICH IS
INTENDED TO BE AN INCENTIVE STOCK OPTION IS NOT AN INCENTIVE STOCK OPTION.

(C)                                  EXERCISE PRICE. THE BOARD SHALL ESTABLISH
THE EXERCISE PRICE AT THE TIME EACH OPTION IS GRANTED AND SPECIFY IT IN THE
APPLICABLE OPTION AGREEMENT, PROVIDED, HOWEVER, THAT THE EXERCISE PRICE SHALL
NOT BE LESS THAN 100% OF THE FAIR MARKET VALUE OF THE COMMON STOCK, AS
DETERMINED BY THE BOARD, AT THE TIME THE OPTION IS GRANTED.

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(D)                                 DURATION OF OPTIONS. EACH OPTION SHALL BE
EXERCISABLE AT SUCH TIMES AND SUBJECT TO SUCH TERMS AND CONDITIONS AS THE BOARD
MAY SPECIFY IN THE APPLICABLE OPTION AGREEMENT, PROVIDED HOWEVER, THAT NO OPTION
WILL BE GRANTED FOR A TERM IN EXCESS OF TEN YEARS.

(E)                                  EXERCISE OF OPTION.  OPTIONS MAY BE
EXERCISED BY DELIVERY TO THE COMPANY OF A WRITTEN NOTICE OF EXERCISE SIGNED BY
THE PROPER PERSON OR BY ANY OTHER FORM OF NOTICE (INCLUDING ELECTRONIC NOTICE)
APPROVED BY THE BOARD TOGETHER WITH PAYMENT IN FULL AS SPECIFIED IN SECTION 5(F)
FOR THE NUMBER OF SHARES FOR WHICH THE OPTION IS EXERCISED.

(F)                                    PAYMENT UPON EXERCISE.  COMMON STOCK
PURCHASED UPON THE EXERCISE OF AN OPTION GRANTED UNDER THE PLAN SHALL BE PAID
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 PROVIDE IN AN OPTION AGREEMENT, BY (I) DELIVERY OF AN
IRREVOCABLE AND UNCONDITIONAL UNDERTAKING BY A CREDITWORTHY BROKER TO DELIVER
PROMPTLY TO THE COMPANY SUFFICIENT FUNDS TO PAY THE EXERCISE PRICE OR (II)
DELIVERY BY THE PARTICIPANT TO THE COMPANY OF A COPY OF IRREVOCABLE AND
UNCONDITIONAL INSTRUCTIONS TO A CREDITWORTHY BROKER TO DELIVER PROMPTLY TO THE
COMPANY CASH OR A CHECK SUFFICIENT TO PAY THE EXERCISE PRICE;

(3)                                  WHEN THE COMMON STOCK IS REGISTERED UNDER
THE EXCHANGE ACT, BY DELIVERY OF SHARES OF COMMON STOCK OWNED BY THE PARTICIPANT
VALUED AT THEIR FAIR MARKET VALUE AS DETERMINED BY (OR IN A MANNER APPROVED BY)
THE BOARD IN GOOD FAITH (“FAIR MARKET VALUE”), PROVIDED (I) SUCH METHOD OF
PAYMENT IS THEN PERMITTED UNDER APPLICABLE LAW AND (II) SUCH COMMON STOCK WAS
OWNED BY THE PARTICIPANT AT LEAST SIX MONTHS PRIOR TO SUCH DELIVERY;

(4)                                  TO THE EXTENT PERMITTED BY THE BOARD, IN
ITS SOLE DISCRETION BY (I) DELIVERY OF A PROMISSORY NOTE OF THE PARTICIPANT TO
THE COMPANY ON TERMS DETERMINED BY THE BOARD, OR (II) PAYMENT OF SUCH OTHER
LAWFUL CONSIDERATION AS THE BOARD MAY DETERMINE; OR

(5)                                  BY ANY COMBINATION OF THE ABOVE PERMITTED
FORMS OF PAYMENT.

(G)                                 SUBSTITUTE OPTIONS. IN CONNECTION WITH A
MERGER OR CONSOLIDATION OF AN ENTITY WITH THE COMPANY OR THE ACQUISITION BY THE
COMPANY OF PROPERTY OR STOCK OF AN ENTITY, THE BOARD MAY GRANT OPTIONS IN
SUBSTITUTION FOR ANY OPTIONS OR OTHER STOCK OR STOCK-BASED AWARDS GRANTED BY
SUCH ENTITY OR AN AFFILIATE THEREOF.  SUBSTITUTE OPTIONS MAY BE GRANTED ON SUCH
TERMS AS THE BOARD DEEMS APPROPRIATE IN THE CIRCUMSTANCES, NOTWITHSTANDING ANY
LIMITATIONS ON OPTIONS CONTAINED IN THE OTHER SECTIONS OF THIS SECTION 5.

6.                                       RESTRICTED STOCK

(A)                                  GRANTS.  THE BOARD MAY GRANT AWARDS
ENTITLING RECIPIENTS TO ACQUIRE SHARES OF COMMON STOCK, SUBJECT TO THE RIGHT OF
THE COMPANY TO REPURCHASE ALL OR PART OF SUCH SHARES AT THEIR ISSUE PRICE OR
OTHER STATED OR FORMULA PRICE (OR TO REQUIRE FORFEITURE OF SUCH SHARES IF ISSUED

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AT NO COST) FROM THE RECIPIENT IN THE EVENT THAT CONDITIONS SPECIFIED BY THE
BOARD IN THE APPLICABLE AWARD ARE NOT SATISFIED PRIOR TO THE END OF THE
APPLICABLE RESTRICTION PERIOD OR PERIODS ESTABLISHED BY THE BOARD FOR SUCH AWARD
(EACH, A “RESTRICTED STOCK AWARD”).

(B)                                 TERMS AND CONDITIONS.  THE BOARD SHALL
DETERMINE THE TERMS AND CONDITIONS OF ANY SUCH RESTRICTED STOCK AWARD, INCLUDING
THE CONDITIONS FOR REPURCHASE (OR FORFEITURE) AND THE ISSUE PRICE, IF ANY.  ANY
STOCK CERTIFICATES ISSUED IN RESPECT OF A RESTRICTED STOCK AWARD SHALL BE
REGISTERED IN THE NAME OF THE PARTICIPANT AND, UNLESS OTHERWISE DETERMINED BY
THE BOARD, DEPOSITED BY THE PARTICIPANT, TOGETHER WITH A STOCK POWER ENDORSED IN
BLANK, WITH THE COMPANY (OR ITS DESIGNEE). AT THE EXPIRATION OF THE APPLICABLE
RESTRICTION PERIODS, THE COMPANY (OR SUCH DESIGNEE) SHALL DELIVER THE
CERTIFICATES NO LONGER SUBJECT TO SUCH RESTRICTIONS TO THE PARTICIPANT OR IF THE
PARTICIPANT HAS DIED, TO THE BENEFICIARY DESIGNATED, IN A MANNER DETERMINED BY
THE BOARD, BY A PARTICIPANT TO RECEIVE AMOUNTS DUE OR EXERCISE RIGHTS OF THE
PARTICIPANT IN THE EVENT OF THE PARTICIPANT’S DEATH (THE “DESIGNATED
BENEFICIARY”).  IN THE ABSENCE OF AN EFFECTIVE DESIGNATION BY A PARTICIPANT,
DESIGNATED BENEFICIARY SHALL MEAN THE PARTICIPANT’S ESTATE.

7.                                       OTHER STOCK-BASED AWARDS

The Board shall have the right to grant other Awards based upon the Common Stock
having such terms and conditions as the Board may determine, including the grant
of shares based upon certain conditions, the grant of securities convertible
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.  IN THE EVENT OF
ANY STOCK SPLIT, REVERSE STOCK SPLIT, STOCK DIVIDEND, RECAPITALIZATION,
COMBINATION OF SHARES, RECLASSIFICATION OF SHARES, SPIN-OFF OR OTHER SIMILAR
CHANGE IN CAPITALIZATION OR EVENT, OR ANY DISTRIBUTION TO HOLDERS OF COMMON
STOCK OTHER THAN A NORMAL CASH DIVIDEND, (I) THE NUMBER AND CLASS OF SECURITIES
AVAILABLE UNDER THIS PLAN, (II) THE PER-PARTICIPANT LIMIT SET FORTH IN SECTION
4(B), (III) THE NUMBER AND CLASS OF SECURITIES AND EXERCISE PRICE PER SHARE
SUBJECT TO EACH OUTSTANDING OPTION, (IV) THE REPURCHASE PRICE PER SHARE SUBJECT
TO EACH OUTSTANDING RESTRICTED STOCK AWARD, AND (V) THE TERMS OF EACH OTHER
OUTSTANDING AWARD SHALL BE APPROPRIATELY ADJUSTED BY THE COMPANY (OR SUBSTITUTED
AWARDS MAY BE MADE, IF APPLICABLE) TO THE EXTENT THE BOARD SHALL DETERMINE, IN
GOOD FAITH, THAT SUCH AN ADJUSTMENT (OR SUBSTITUTION) IS NECESSARY AND
APPROPRIATE.  IF THIS SECTION 8(A) APPLIES AND SECTION 8(C) ALSO APPLIES TO ANY
EVENT, SECTION 8(C) SHALL BE APPLICABLE TO SUCH EVENT, AND THIS SECTION 8(A)
SHALL NOT BE APPLICABLE.

(B)                                 LIQUIDATION OR DISSOLUTION.  IN THE EVENT OF
A PROPOSED LIQUIDATION OR DISSOLUTION OF THE COMPANY, THE BOARD SHALL UPON
WRITTEN NOTICE TO THE PARTICIPANTS PROVIDE THAT ALL THEN UNEXERCISED OPTIONS
WILL (I) BECOME EXERCISABLE IN FULL AS OF A SPECIFIED TIME AT LEAST 10 BUSINESS
DAYS PRIOR TO THE EFFECTIVE DATE OF SUCH LIQUIDATION OR DISSOLUTION AND (II)
TERMINATE EFFECTIVE UPON SUCH LIQUIDATION OR DISSOLUTION, EXCEPT TO THE EXTENT
EXERCISED BEFORE SUCH EFFECTIVE DATE.  THE BOARD MAY SPECIFY THE EFFECT OF A
LIQUIDATION OR DISSOLUTION ON ANY RESTRICTED STOCK AWARD OR OTHER AWARD GRANTED
UNDER THE PLAN AT THE TIME OF THE GRANT OF SUCH AWARD.

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(c)                                  Acquisition and Change in Control Events

(1)                                  Definitions

(a)                                  An “Acquisition Event” shall mean:

(i)                                     any merger or consolidation of the
Company with or into another entity as a result of which the Common Stock is
converted into or exchanged for the right to receive cash, securities or other
property; or

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

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

(i)                                     the acquisition by an individual, entity
or group (within the meaning of Section 13(d)(3) or 14(d)(2) of the Securities
Exchange Act of 1934, as amended (the “Exchange Act”)) (a “Person”) of
beneficial ownership of any capital stock of the Company if, after such
acquisition, such Person beneficially owns (within the meaning of Rule 13d-3
promulgated under the Exchange Act) 30% or more of either (x) the
then-outstanding shares of common stock of the Company (the “Outstanding Company
Common Stock”) or (y) the combined voting power of the then-outstanding
securities of the Company 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 not
constitute a Change in Control Event: (A) any acquisition directly from the
Company (excluding an acquisition pursuant to the exercise, conversion or
exchange of any security exercisable for, convertible into or exchangeable for
common stock or voting securities of the Company, unless the Person exercising,
converting or exchanging such security acquired such security directly from the
Company or an underwriter or agent of the Company), (B) any acquisition by any
employee benefit plan (or related trust) sponsored or maintained by the Company
or any corporation controlled by the Company, or (C) any acquisition by any
corporation pursuant to a Business Combination (as defined below) which complies

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with clauses (x) and (y)  of subsection (iii) of this definition; or

(ii)                                  such time as the Continuing Directors (as
defined below) do not constitute a majority of the Board (or, if applicable, the
Board of Directors of a successor corporation to the Company), where the term
“Continuing Director” means at any date a member of the Board (x) who was a
member of 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 a
majority of the directors who were Continuing Directors at the time of such
nomination or election or whose election to the Board was recommended or
endorsed by at least a majority of the directors who were Continuing Directors
at 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 result of an actual or threatened election contest with
respect to the election or removal of directors or other actual or threatened
solicitation of proxies or consents, by or on behalf of a person other than the
Board; or

(iii)                               the consummation of a merger, consolidation,
reorganization, recapitalization or statutory share exchange involving the
Company or a sale or other disposition of all or substantially all of the assets
of the Company (a “Business Combination”), unless, immediately following such
Business Combination, each of the following two conditions is satisfied: (x) all
or substantially all of the individuals and entities who were the beneficial
owners of the Outstanding Company Common Stock and Outstanding Company Voting
Securities immediately prior to such Business Combination beneficially own,
directly or indirectly, more than 50% of the then-outstanding shares of common
stock and the combined voting power of the then-outstanding securities entitled
to vote generally in the election of directors, respectively, of the resulting
or acquiring corporation in such Business Combination (which shall include,
without limitation, a corporation which as a result of such transaction owns the
Company or substantially all of the Company’s assets either directly or through
one or more subsidiaries) (such resulting or acquiring corporation is referred
to herein as the

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“Acquiring Corporation”) in substantially the same proportions as their
ownership of the Outstanding Company Common Stock and Outstanding Company Voting
Securities, respectively, immediately prior to such Business Combination and (y)
no Person (excluding the Acquiring Corporation or any employee benefit plan (or
related trust) maintained or sponsored by the Company or by the Acquiring
Corporation) beneficially owns, directly or indirectly, 30% or more of the
then-outstanding shares of common stock of the Acquiring Corporation, or of the
combined voting power of the then-outstanding securities of such corporation
entitled to vote generally in the election of directors (except to the extent
that such ownership existed prior to the Business Combination).

(2)                                  Effect on Options

(a)                                  Acquisition Event.  Upon the occurrence of
an Acquisition Event (regardless of whether such event also constitutes a Change
in Control Event), or the execution 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, or equivalent options shall be substituted, by the acquiring
or succeeding corporation (or an affiliate thereof); provided that if such
Acquisition Event also constitutes a Change in Control Event, except to the
extent specifically provided to the contrary in the instrument evidencing any
Option or any other agreement between a Participant and the Company, such
assumed or substituted options shall be immediately exercisable in full upon the
occurrence of such Acquisition Event.  For purposes hereof, an Option shall be
considered to be assumed if, following consummation of the Acquisition Event,
the Option confers the right to purchase, for each share of Common Stock subject
to the Option immediately prior to the consummation of the Acquisition Event,
the consideration (whether cash, securities or other property) received as a
result of the Acquisition Event by holders of Common Stock for each share of
Common Stock held immediately prior to the consummation of the Acquisition Event
(and if holders were offered a choice of consideration, the type of
consideration chosen by the holders of a majority of the outstanding shares of
Common Stock); provided, however, that if the consideration received as a result
of the Acquisition Event is not solely common stock of the acquiring or
succeeding

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corporation (or an affiliate thereof), the Company may, with the consent of the
acquiring or succeeding corporation, provide for the consideration to be
received upon the exercise of Options to consist solely of common stock of the
acquiring or succeeding corporation (or an affiliate thereof) equivalent in fair
market value to the per share consideration received by holders of outstanding
shares of Common Stock as a result of the Acquisition Event.

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

(b)                                 Change in Control Event that is not an
Acquisition Event.  Upon the occurrence of a Change in Control Event that does
not also constitute an Acquisition Event, except to the extent specifically
provided to the contrary in the instrument evidencing any Option or any other
agreement between a Participant and the Company, all Options then-outstanding
shall automatically become immediately exercisable in full.

(3)                                  Effect on Restricted Stock Awards

(a)                                  Acquisition Event that is not a Change in
Control Event. Upon the occurrence of an Acquisition Event that is not a Change
in Control Event, the repurchase and other rights of the Company under each
outstanding Restricted Stock Award shall inure to the benefit of the Company’s
successor and shall apply to the cash, securities or other property which the
Common Stock was converted into or

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exchanged for pursuant to such Acquisition Event in the same manner and to the
same extent as they applied to the Common Stock subject to such Restricted Stock
Award.

(b)                                 Change in Control 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 instrument evidencing any Restricted Stock Award or any
other agreement between a Participant and the Company, all restrictions and
conditions on all Restricted Stock Awards then-outstanding shall automatically
be deemed terminated or satisfied.

(4)                                  Effect on Other Awards

(a)                                  Acquisition Event that is not a Change in
Control Event. The Board shall specify the effect of an Acquisition Event that
is not a Change in Control Event on any other Award granted under the Plan at
the time of the grant of such Award.

(b)                                 Change in Control 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 instrument evidencing any other Award or any other agreement
between a Participant and the Company, all other Awards shall become
exercisable, realizable or vested in full, or shall be free of all conditions or
restrictions, as applicable to each such Award.

(5)                                  Limitations.  Notwithstanding the foregoing
provisions of this Section 8(c), if the Change in Control Event is intended to
be accounted 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) would preclude accounting for the Change in Control Event as a
“pooling of interests” for financial accounting purposes, then no such
acceleration shall occur upon the Change in Control Event.

9.                                       GENERAL PROVISIONS APPLICABLE TO AWARDS

(A)                                  TRANSFERABILITY OF AWARDS.  EXCEPT AS THE
BOARD MAY OTHERWISE DETERMINE OR PROVIDE IN AN AWARD, AWARDS SHALL NOT BE SOLD,
ASSIGNED, TRANSFERRED, PLEDGED OR OTHERWISE ENCUMBERED BY THE PERSON TO WHOM
THEY ARE GRANTED, EITHER VOLUNTARILY OR BY OPERATION OF LAW, EXCEPT BY WILL OR
THE LAWS OF DESCENT AND DISTRIBUTION, AND, DURING THE LIFE OF THE PARTICIPANT,
SHALL

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BE EXERCISABLE ONLY BY THE PARTICIPANT.  REFERENCES TO A PARTICIPANT, TO THE
EXTENT RELEVANT IN THE CONTEXT, SHALL INCLUDE REFERENCES TO AUTHORIZED
TRANSFEREES.

(B)                                 DOCUMENTATION.  EACH AWARD SHALL BE
EVIDENCED BY A WRITTEN INSTRUMENT IN SUCH FORM AS THE BOARD SHALL DETERMINE.
EACH AWARD MAY CONTAIN TERMS AND CONDITIONS IN ADDITION TO THOSE SET FORTH IN
THE PLAN.

(C)                                  BOARD DISCRETION.  EXCEPT AS OTHERWISE
PROVIDED BY THE PLAN, EACH AWARD MAY BE MADE ALONE OR IN ADDITION OR IN RELATION
TO ANY OTHER AWARD.  THE TERMS OF EACH AWARD NEED NOT BE IDENTICAL, AND THE
BOARD NEED NOT TREAT PARTICIPANTS UNIFORMLY.

(D)                                 TERMINATION OF STATUS.  THE BOARD SHALL
DETERMINE THE EFFECT ON AN AWARD OF THE DISABILITY, DEATH, RETIREMENT,
AUTHORIZED LEAVE OF ABSENCE OR OTHER CHANGE IN THE EMPLOYMENT OR OTHER STATUS OF
A PARTICIPANT AND THE EXTENT TO WHICH, AND THE PERIOD DURING WHICH, THE
PARTICIPANT, THE PARTICIPANT’S LEGAL REPRESENTATIVE, CONSERVATOR, GUARDIAN OR
DESIGNATED BENEFICIARY MAY EXERCISE RIGHTS UNDER THE AWARD.

(E)                                  WITHHOLDING.  EACH PARTICIPANT SHALL PAY TO
THE COMPANY, OR MAKE PROVISION SATISFACTORY TO THE BOARD FOR PAYMENT OF, ANY
TAXES REQUIRED BY LAW TO BE WITHHELD IN CONNECTION WITH AWARDS TO SUCH
PARTICIPANT NO LATER THAN THE DATE OF THE EVENT CREATING THE TAX LIABILITY. 
EXCEPT AS THE BOARD MAY OTHERWISE PROVIDE IN AN AWARD, WHEN THE COMMON STOCK IS
REGISTERED UNDER THE EXCHANGE ACT, PARTICIPANTS MAY, TO THE EXTENT THEN
PERMITTED UNDER APPLICABLE LAW, SATISFY SUCH TAX OBLIGATIONS IN WHOLE OR IN PART
BY DELIVERY OF SHARES OF COMMON STOCK, INCLUDING SHARES RETAINED FROM THE AWARD
CREATING THE TAX OBLIGATION, VALUED AT THEIR FAIR MARKET VALUE. THE COMPANY MAY,
TO THE EXTENT PERMITTED BY LAW, DEDUCT ANY SUCH TAX OBLIGATIONS FROM ANY PAYMENT
OF ANY KIND OTHERWISE DUE TO A PARTICIPANT.

(F)                                    AMENDMENT OF AWARD.  THE BOARD MAY AMEND,
MODIFY OR TERMINATE ANY OUTSTANDING AWARD, INCLUDING BUT NOT LIMITED TO,
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 BOARD DETERMINES THAT THE ACTION, TAKING
INTO ACCOUNT ANY RELATED ACTION, WOULD NOT MATERIALLY AND ADVERSELY AFFECT THE
PARTICIPANT.

(G)                                 CONDITIONS ON DELIVERY OF STOCK.  THE
COMPANY WILL NOT BE OBLIGATED TO DELIVER ANY SHARES OF COMMON STOCK PURSUANT TO
THE PLAN OR TO REMOVE RESTRICTIONS FROM SHARES PREVIOUSLY DELIVERED UNDER THE
PLAN UNTIL (I) ALL CONDITIONS OF THE AWARD HAVE BEEN MET OR REMOVED TO THE
SATISFACTION OF THE COMPANY, (II) IN THE OPINION OF THE COMPANY’S COUNSEL, ALL
OTHER LEGAL MATTERS IN CONNECTION WITH THE ISSUANCE AND DELIVERY OF SUCH SHARES
HAVE BEEN SATISFIED, INCLUDING ANY APPLICABLE SECURITIES LAWS AND ANY APPLICABLE
STOCK EXCHANGE OR STOCK MARKET RULES AND REGULATIONS, AND (III) THE PARTICIPANT
HAS EXECUTED AND DELIVERED TO THE COMPANY SUCH REPRESENTATIONS OR AGREEMENTS AS
THE COMPANY MAY CONSIDER APPROPRIATE TO SATISFY THE REQUIREMENTS OF ANY
APPLICABLE LAWS, RULES OR REGULATIONS.

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(H)                                 ACCELERATION.  THE BOARD MAY AT ANY TIME
PROVIDE THAT ANY OPTIONS SHALL BECOME IMMEDIATELY EXERCISABLE IN FULL OR IN
PART, THAT ANY RESTRICTED STOCK AWARDS SHALL BE FREE OF RESTRICTIONS IN FULL OR
IN PART OR THAT ANY OTHER AWARDS MAY BECOME EXERCISABLE IN FULL OR IN PART OR
FREE OF SOME OR ALL RESTRICTIONS OR CONDITIONS, OR OTHERWISE REALIZABLE IN FULL
OR IN PART, AS THE CASE MAY BE.

10.                                 MISCELLANEOUS

(A)                                  NO RIGHT TO EMPLOYMENT OR OTHER STATUS.  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 OR ANY OTHER RELATIONSHIP WITH THE COMPANY.  THE COMPANY EXPRESSLY
RESERVES THE RIGHT AT ANY TIME TO DISMISS OR OTHERWISE TERMINATE ITS
RELATIONSHIP WITH 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 WITH RESPECT TO AN AWARD UNTIL BECOMING THE RECORD
HOLDER OF SUCH SHARES.  NOTWITHSTANDING THE FOREGOING, IN THE EVENT THE COMPANY
EFFECTS A SPLIT OF THE COMMON STOCK BY MEANS OF A STOCK DIVIDEND AND THE
EXERCISE PRICE OF AND THE NUMBER OF SHARES SUBJECT TO SUCH OPTION ARE ADJUSTED
AS OF THE DATE OF THE DISTRIBUTION OF THE DIVIDEND (RATHER THAN AS OF THE RECORD
DATE FOR SUCH DIVIDEND), THEN AN OPTIONEE WHO EXERCISES AN OPTION BETWEEN THE
RECORD DATE AND THE DISTRIBUTION DATE FOR SUCH STOCK DIVIDEND SHALL BE ENTITLED
TO RECEIVE, ON THE DISTRIBUTION DATE, THE STOCK DIVIDEND WITH RESPECT TO THE
SHARES OF COMMON STOCK ACQUIRED UPON SUCH OPTION EXERCISE, NOTWITHSTANDING THE
FACT THAT SUCH SHARES WERE NOT OUTSTANDING AS OF THE CLOSE OF BUSINESS ON THE
RECORD DATE FOR SUCH STOCK DIVIDEND.

(C)                                  EFFECTIVE DATE AND TERM OF PLAN.  THE PLAN
SHALL BECOME EFFECTIVE ON THE DATE ON WHICH IT IS ADOPTED BY THE BOARD, BUT NO
AWARD GRANTED TO A PARTICIPANT THAT IS INTENDED TO COMPLY WITH SECTION 162(M)
SHALL BECOME EXERCISABLE, VESTED OR REALIZABLE, AS APPLICABLE TO SUCH AWARD,
UNLESS AND UNTIL THE PLAN HAS BEEN APPROVED BY THE COMPANY’S STOCKHOLDERS TO THE
EXTENT STOCKHOLDER APPROVAL IS REQUIRED BY SECTION 162(M) IN THE MANNER REQUIRED
UNDER SECTION 162(M) (INCLUDING THE VOTE REQUIRED UNDER SECTION 162(M)). NO
AWARDS SHALL BE GRANTED UNDER THE PLAN AFTER THE COMPLETION OF TEN YEARS FROM
THE EARLIER OF (I) THE DATE ON WHICH THE PLAN WAS ADOPTED BY THE BOARD OR (II)
THE DATE THE PLAN WAS APPROVED BY THE COMPANY’S STOCKHOLDERS, BUT AWARDS
PREVIOUSLY GRANTED MAY EXTEND BEYOND THAT DATE.

(D)                                 AMENDMENT OF PLAN.  THE BOARD MAY AMEND,
SUSPEND OR TERMINATE THE PLAN OR ANY PORTION THEREOF AT ANY TIME, PROVIDED THAT
TO THE EXTENT REQUIRED BY SECTION 162(M), NO AWARD GRANTED TO A PARTICIPANT THAT
IS INTENDED TO COMPLY WITH SECTION 162(M) AFTER THE DATE OF SUCH AMENDMENT SHALL
BECOME EXERCISABLE, REALIZABLE OR VESTED, AS APPLICABLE TO SUCH AWARD, UNLESS
AND UNTIL SUCH AMENDMENT SHALL HAVE BEEN APPROVED BY THE COMPANY’S STOCKHOLDERS
AS REQUIRED BY SECTION 162(M) (INCLUDING THE VOTE REQUIRED UNDER SECTION
162(M)).

11

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(E)                                  GOVERNING LAW.  THE PROVISIONS OF THE PLAN
AND ALL AWARDS MADE HEREUNDER SHALL BE GOVERNED BY AND INTERPRETED IN ACCORDANCE
WITH THE LAWS OF THE STATE OF DELAWARE, WITHOUT REGARD TO ANY APPLICABLE
CONFLICTS OF LAW.

Adopted by the Board of Directors on February 24, 2000

Adopted by the Stockholders on May 24, 2000

12

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AMENDMENT NO 1. TO

2000 STOCK INCENTIVE PLAN

OF

SEPRACOR INC.

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

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

“(a) Number of Shares.  Subject to adjustment under Section 8, Awards may be
made under the Plan for up to 4,000,000 shares of common stock, $.10 par value
per share, of the Company (the “Common Stock”).  If any Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on February 21, 2002

Adopted by the Stockholders on May 22, 2002

13

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AMENDMENT NO 2. TO

2000 STOCK INCENTIVE PLAN

OF

SEPRACOR INC.

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

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

“(a) Number of Shares.  Subject to adjustment under Section 8, Awards may be
made under the Plan for up to 5,5000,000 shares of common stock, $.10 par value
per share, of the Company (the “Common Stock”).  If any Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on February 20, 2003

Adopted by the Stockholders on May 22, 2003

14

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AMENDMENT NO 3. TO

2000 STOCK INCENTIVE PLAN

OF

SEPRACOR INC.

The 2000 Stock Incentive 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 substituted in 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 Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on February 11, 2004.

Adopted by the Stockholders on May 19, 2004.

15

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AMENDMENT NO. 4 TO

2000 STOCK INCENTIVE PLAN

OF

SEPRACOR INC.

The 2000 Stock Incentive 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 substituted in 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 Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on April 1, 2005.

Adopted by the Stockholders on May 19, 2005.

16

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AMENDMENT NO. 5 TO
2000 STOCK INCENTIVE PLAN
OF
SEPRACOR INC.

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

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

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

2.                                       Section 9(f) is hereby 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 but not limited to, substituting therefore another Award of the same
or a different type, changing the date of exercise or realization, and
converting an Incentive Stock Option to a Non-Statutory Stock Option, provided
that the Participant’s consent to such action shall be required unless the Board
determines that the action, taking into account any related action, would not
materially and adversely affect the Participant.

Adopted by the Board of Directors on May 13, 2005

17

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AMENDMENT NO. 6 TO
2000 STOCK INCENTIVE PLAN
OF
SEPRACOR INC.

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

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

“(a) Number of Shares.  Subject to adjustment under Section 8, Awards may be
made under the Plan for up to 11,500,000 shares of common stock, $.10 par value
per share, of the Company (the “Common Stock”).  If any Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on April 5, 2006.

Adopted by the Stockholders on May 18, 2006.

18

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AMENDMENT NO. 7 TO
2000 STOCK INCENTIVE PLAN
OF
SEPRACOR INC.

The 2000 Stock Incentive 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 substituted in its place:

 “(a)  Number of Shares.  Subject to adjustment under Section 8, Awards may be
made under the Plan for up to 13,500,000 shares of common stock, $.10 par value
per share, of the Company (the “Common Stock”).  If any Award expires or is
terminated, surrendered or cancelled without having been fully exercised or is
forfeited in whole or in part or results in any Common Stock not being issued,
the unused Common Stock covered by such Award shall again be available for the
grant of Awards under the Plan, subject, however, in the case of Incentive Stock
Options (as hereinafter defined), to any limitation required under the Code. 
Shares issued under the Plan may consist in whole or in part of authorized but
unissued shares or treasury shares.”

Adopted by the Board of Directors on March 8, 2007.

Adopted by the Stockholders on May 15, 2007.

19

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