UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

WASHINGTON, D.C. 20549

FORM 8-K

CURRENT REPORT
Pursuant to Section 13 OR 15(d) of The Securities Exchange Act of 1934

Date of Report (Date of earliest event reported):  March 4, 2009

Sepracor Inc.

(Exact Name of Registrant as Specified in its Charter)

Delaware	0-19410	22-2536587
(State or Other Juris- diction of Incorporation	(Commission File Number)	(IRS Employer Identification No.)

84 Waterford Drive Marlborough, MA	01752
(Address of Principal Executive Offices)	(Zip Code)

Registrant’s telephone number, including area code:  (508) 481-6700

(Former Name or Former Address, if Changed Since Last Report)

Check the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions (see General Instruction A.2. below):

o Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425)

o Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12)

o Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b))

o Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c))

Item 8.01  Other Events

On March 5, 2009 Sepracor Inc. (“Sepracor”) announced that it has completed the analysis and validation of the preliminary results of a Phase II, 440-patient study evaluating the efficacy and safety of SEP-225441, a modified-release formulation of eszopiclone for the treatment of generalized anxiety disorder (“GAD”).  Sepracor determined that the study did not meet its primary efficacy endpoint, which was reduction in symptoms of GAD as assessed using the clinician-rated HAM-A scale (Hamilton Anxiety Rating Scale, a standard scale used to assess anxiety in clinical trials and consisting of a list of symptoms commonly associated with anxiety).  Sepracor is in the process of further analyzing the data in an effort to determine whether any of the secondary endpoints were met and whether this compound warrants further clinical development.

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SIGNATURES

Pursuant to the requirements of the Securities Exchange Act of 1934, the registrant has duly caused this report to be signed on its behalf by the undersigned hereunto duly authorized.

	Sepracor Inc.
Date: March 5, 2009	By:	/s/ Andrew I. Koven
	Name: Andrew I. Koven
	Title: Executive Vice President, General Counsel and Corporate Secretary

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