Exhibit 10.10

SEPRACOR INC.

2008 DIRECTOR STOCK INCENTIVE PLAN

1.Purpose

The
purpose of this 2008 Director 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 outside directors of the Company and by providing such persons with equity ownership opportunities and performance-based
incentives that are intended to better align the interests of such persons with those of the Company's stockholders.

2.Eligibility

Each
director of the Company who is not an employee of the Company is eligible to be granted options and restricted stock (each, an "Award") under the Plan. Each person who receives an
Award under the Plan is deemed a "Participant".

3.Administration and 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 construe and interpret the
terms of the Plan and any Award agreements entered into under the Plan. 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 mean the Board or a Committee of the Board 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)Authorized Number of Shares.Subject to adjustment under Section 7, Awards may be made under the Plan
for up to 500,000 shares of common stock, $0.10 par value per share, of the Company (the "Common Stock"). Shares issued under the Plan may consist in whole or in part of authorized but unissued shares
or treasury shares.

(b)Share Counting.For purposes of counting the number of shares available for the grant of Awards under the
Plan (i) if any Award (A) expires or is terminated, surrendered or canceled without having been fully exercised or is forfeited in whole or in part (including as the result of shares of
Common Stock subject to such Award being repurchased by the Company at the original issuance price pursuant to a contractual repurchase right) or (B) 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; (ii) shares of Common Stock delivered (either by actual delivery or attestation) to the
Company by a Participant to (A) purchase shares of Common Stock upon the exercise of an Award or (B) satisfy tax

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withholding
obligations (including shares retained from the Award creating the tax obligation) shall not be added back to the number of shares available for the future grant of Awards; and
(iii) shares of Common Stock repurchased by the Company on the open market using the proceeds from the exercise of an Award shall not increase the number of shares available for future grant of
Awards.

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. All Options granted under this Plan shall be designated "Nonstatutory Stock Options."

(b)Initial Grant.Upon the commencement of service on the Board by any individual who is not then an employee
of the Company or any subsidiary of the Company, the Company shall grant to such person a Nonstatutory Stock Option to purchase 20,000 shares of Common Stock (subject to adjustment under
Section 7).

(c)Annual Grant.On the date of each annual meeting of stockholders of the Company, the Company shall grant to
each member of the Board of Directors of the Company who is both serving as a director of the Company immediately prior to and immediately following such annual meeting and who is not then an employee
of the Company or any of its subsidiaries, a Nonstatutory Stock Option to purchase 10,000 shares of Common Stock (subject to adjustment under Section 7); provided, however, that a director
shall not be eligible to receive an option grant under this Section 5(c) until such director has served on the Board for at least six months.

(d)Terms of Director Options.Options granted under this Section 5 shall:



provided
that no additional vesting shall take place after the Participant ceases to serve as a director and further provided that, in addition to the acceleration of vesting provided for in
Section 5(e) and 7(c), the Board may provide for accelerated vesting in the case of attainment of mandatory retirement age or retirement following at least 10 years of service,



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(e)Vesting Upon Death or Disability.



(f)Form of Exercise.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(g) for the number of shares for
which the Option is exercised. Shares of Common Stock subject to the Option will be delivered by the Company as soon as practicable following exercise.

(g)Payment Upon Exercise.Common Stock purchased upon the exercise of an Option granted under the Plan shall be
paid for as follows:



(h)Board Discretion.The Board retains the specific authority to from time to time increase or decrease the
number of shares subject to Options granted under this Section 5, subject to the limitation on the aggregate number of shares issuable to non-employee directors contained in
Section 4(a). The Board also retains the specific authority to issue Restricted Stock Awards in lieu of some or all of the Options otherwise issuable under this Section 5, subject to the
limitation on the aggregate number of shares issuable to non-employee directors contained in Section 4(a).

(i)Limitation on Repricing.Unless such action is approved by the Company's stockholders: (1) 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 7) and (2) the Board may not cancel any outstanding option

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(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.

6.Restricted Stock

(a)General.The Board may grant Awards entitling recipients to acquire shares of Common Stock ("Restricted
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 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.

(b)Annual Grant.



(c)Board Discretion.The Board retains the specific authority to from time to time increase or decrease the
number of shares of Restricted Stock granted under this Section 6, subject to the limitation on the aggregate number of shares issuable to non-employee directors contained in
Section 4(a). The Board also retains the specific authority to issue Options in lieu of some or all of the Restricted Stock otherwise issuable under this Section 4, subject to the
limitation on the aggregate number of shares issuable to non-employee directors contained in Section 4(a).

(d)Additional Provisions Relating to Restricted Stock.



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7.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 dividend or distribution to holders of Common Stock
other than an ordinary cash dividend, (i) the number and class of securities available under this Plan, (ii) share counting rules set forth in Section 4(b) , (iii) the
number and class of securities and exercise price per share of each outstanding Option and each Option issuable under Section 5, (iv) the number of shares subject to and the repurchase
price per share subject to each outstanding Restricted Stock Award and each Restricted Stock Award issuable under Section 6, shall be equitably adjusted by the Company (or substituted Awards
may be made, if applicable) in the manner determined by the Board. Without limiting the generality of 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 an outstanding 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.

(b)Reorganization Events.



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(c)   Change in Control Events.



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8.General Provisions Applicable to Awards

(a)Transferability of Awards.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 or pursuant to a qualified domestic relations order, and,
during the life of the Participant, shall be exercisable only by the Participant; provided, however, that the Board may permit or provide in an Award for the gratuitous transfer of the Award by the
Participant to or for the benefit of any immediate family member, family trust or other entity established for the benefit of the Participant and/or an immediate family member thereof if, with respect
to such proposed transferee, the Company would be eligible to use a Form S-8 for the registration of the sale of the Common Stock subject to such Award under the Securities Act of
1933, as amended; provided, further, that the Company shall not be required to recognize any such transfer until such time as the Participant and such permitted transferee shall, as a condition to
such transfer, deliver to the Company a written instrument in form and substance satisfactory to the Company confirming that such transferee shall be bound by all of the terms and conditions of the
Award. References to a Participant, to the extent relevant in the context, shall include references to authorized transferees.

(b)Documentation.Each Award shall be evidenced in such form (written, electronic or otherwise) 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,
termination or other cessation of employment, authorized leave of absence or other change in

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the
employment or other status of a Participant and the extent to which, and the period during which, the Participant, or the Participant's legal representative, conservator, guardian or Designated
Beneficiary, may exercise rights under the Award.

(e)Withholding.The Participant must satisfy all applicable federal, state, and local or other income and
employment tax withholding obligations before the Company will deliver stock certificates or otherwise recognize ownership of Common Stock under an Award. The Company may decide to satisfy the
withholding obligations through additional withholding on salary or wages. If the Company elects not to or cannot withhold from other compensation, the Participant must pay the Company the full
amount, if any, required for withholding or have a broker tender to the Company cash equal to the withholding obligations. Payment of withholding obligations is due before the Company will issue any
shares on exercise or release from forfeiture of an Award or, if the Company so requires, at the same time as is payment of the exercise price unless the Company determines otherwise. If provided for
in an Award or approved by the Board in its sole discretion, a Participant may satisfy such tax obligations in whole or in part by delivery (either by actual delivery or attestation) of shares of
Common Stock, including shares retained from the Award creating the tax obligation, valued at their Fair Market Value; provided, however, except as otherwise provided by the Board, that the total tax
withholding where stock is being used to satisfy such tax obligations cannot exceed the Company's minimum statutory withholding obligations (based on minimum statutory withholding rates for federal
and state tax purposes, including payroll taxes, that are applicable to such supplemental taxable income). Shares used to satisfy tax withholding requirements cannot be subject to any repurchase,
forfeiture, unfulfilled vesting or other similar requirements.

(f)Amendment of Award.Except as otherwise provided in Section 5(i) with respect to repricings or
Section 9(d) with respect to actions requiring shareholder approval, 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 and changing the date of exercise or realization. The Participant's consent to such action shall be required unless (i) the Board determines that the
action, taking into account any related action, would not materially and adversely affect the Participant's rights under the Plan or (ii) the change is permitted under Section 7 hereof.

(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.

(h)Acceleration.The Board may at any time provide that any Award shall become immediately exercisable in full
or in part, free of some or all restrictions or conditions, or otherwise realizable in full or in part, as the case may be.

9.Miscellaneous

(a)No Right To Board Membership 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 continue as a director of the Company or to maintain any other role 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.

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(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.

(c)Effective Date and Term of Plan.The Plan shall become effective on the date the Plan is approved by the
Company's stockholders (the "Effective Date"). No Awards shall be granted under the Plan after the expiration of 10 years from the Effective Date, 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 (i) no amendment that would require stockholder approval under the rules of the NASDAQ Stock Market ("NASDAQ") may be made effective unless and until such amendment shall have
been approved by the Company's stockholders; and (ii) if NASDAQ amends its corporate governance rules so that such rules no longer require stockholder approval of NASDAQ "material amendments"
to equity compensation plans, then, from and after the effective date of such amendment to the NASDAQ rules, no amendment to the Plan (A) materially increasing the number of shares authorized
under the Plan (other than pursuant to Section 7), (B) expanding the types of Awards that may be granted under the Plan, or (C) materially expanding the class of participants
eligible to participate in the Plan shall be effective unless stockholder approval is obtained. Unless otherwise specified in the amendment, any amendment to the Plan adopted in accordance with this
Section 9(d)
shall apply to, and be binding on the holders of, all Awards outstanding under the Plan at the time the amendment is adopted, provided the Board determines that such amendment does not materially and
adversely affect the rights of Participants under the Plan. No Award shall be made that is conditioned upon stockholder approval of any amendment to the Plan.

(e)Provisions for Foreign Participants.The Board may modify Awards granted to Participants who are foreign
nationals or employed outside the United States or establish subplans or procedures under the Plan to recognize differences in laws, rules, regulations or customs of such foreign jurisdictions with
respect to tax, securities, currency, employee benefit or other matters.

(f)Compliance with Code Section 409A.No Award shall provide for deferral of compensation that does not
comply with Section 409A of the Code, unless the Board, at the time of grant, specifically provides that the Award is not intended to comply with Section 409A of the Code. The Company
shall have no liability to a Participant, or any other party, if an Award that is intended to be exempt from, or compliant with, Section 409A is not so exempt or compliant or for any action
taken by the Board.

(g)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, excluding choice-of-law principles of the law of such state that would require the application of the laws of a
jurisdiction other than such state.

Adopted
by the Board of Directors on February 26, 2008

Adopted
by the Stockholders on May 20, 2008

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