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Exhibit 10.47

SUMMARY OF EXECUTIVE OFFICER COMPENSATION

Executive Officer Compensation—Payout of 2007 Bonuses

        On January 24, 2008, the Compensation Committee (the "Committee") of the
Board of Directors of Sepracor Inc. (the "Company") approved bonus payments to
the Company's executive officers with respect to their performance during 2007.
The following table sets forth the bonus payments for 2007 paid to each of the
Company's executive officers.

Executive Officer

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  2007 Target
Bonus

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  2007 Bonus
Payment

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  Timothy J. Barberich
Executive Chairman; Former Chief Executive Officer   $ 731,500   $ 660,000  
Adrian Adams
President and Chief Executive Officer   $ 800,000   $ 666,640 (1) Mark H.N.
Corrigan, M.D.
Executive Vice President, Research and Development   $ 258,638   $ 235,000  
David P. Southwell
Executive Vice President, Chief Financial Officer and Secretary   $ 252,890   $
230,000   Andrew I. Koven
Executive Vice President, General Counsel and Corporate Secretary   $ 250,000  
$ 210,000 (1) Robert F. Scumaci
Executive Vice President, Finance and Administration, Treasurer   $ 247,143   $
225,000   Mark Iwicki
Executive Vice President, Chief Commercial Officer   $ 285,000   $ 75,000 (2)

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(1)Amount represents the portion of target bonuses payable to Messrs. Adams and
Koven pro rated from the start of their employment in March 2007.

(2)Mr. Iwicki was guaranteed a 2007 bonus of $75,000.

Executive Officer Compensation for 2008—Base Salary and Target Bonus

        On January 24, 2008, the Committee approved the annual base salaries to
be paid to the Company's executive officers during 2008. In addition, the
Committee established target bonuses for each executive officer as a percentage
of each executive officer's annual base salary. Each executive officer's bonus
for 2008 shall be determined based on, among other things, the Company's overall
performance, as well as such officer's individual performance, during 2008. The
following table sets

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forth the annual base salary for 2008 and 2008 target bonus for each of the
Company's executive officers.

Executive Officer

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  Annual Base
Salary for 2008

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  2008 Target
Bonus Percentage

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  2008
Target Bonus

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Timothy J. Barberich   $ 960,000   80 % $ 768,000 Adrian Adams   $ 1,050,000  
100 % $ 1,050,000 Mark H.N. Corrigan, M.D.    $ 545,000   50 % $ 272,500 David
P. Southwell   $ 530,000   50 % $ 265,000 Andrew I. Koven   $ 525,000   50 % $
262,500 Robert F. Scumaci   $ 520,000   50 % $ 260,000 Mark Iwicki   $ 500,000  
60 % $ 300,000

Stock Option and Restricted Stock Awards

        Each executive officer may also be granted stock options, restricted
stock or other awards pursuant to the Company's equity incentive plans. The
Committee may approve annual equity awards at its meeting that coincides with
the Company's annual meeting of stockholders and may approve grants to newly
named executive officers at its first meeting following the executive's first
day of employment. With the approval of the full Board, additional equity awards
may be granted to executive officers.

Other Compensation

        The Company has also (1) entered into employment agreements with
Messrs. Adams, Koven and Iwicki, (2) entered into letter agreements that include
severance provisions with Dr. Corrigan and Messrs. Scumaci and Southwell,
(3) entered into executive retention agreements with each of its executive
officers, (4) entered into an executive retirement agreement with Mr. Barberich,
and (5) agreed to make gross up payments to each of its executive officers in
the event that any payments received by them in connection with a change of
control constitute parachute payments under Section 280G of the Internal Revenue
Code of 1986, as amended. The Company has previously filed these letter
agreements, employment agreements, executive retention agreements, executive
retirement agreement and a summary of the 280G gross up plan with the Securities
and Exchange Commission.

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Exhibit 10.47