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Exhibit 10.1    
    


 
 

AMENDMENT AND PATENT ASSIGNMENT AGREEMENT    
    


        This Amendment and Patent Assignment Agreement (this "Amendment"), dated as of this 2nd day of July, 2004 (the
"Amendment Date"), is made by and between Sepracor Inc., a Delaware corporation ("Sepracor"), and
Aventis Pharma SA (successor in interest to Rhone-Poulenc Rorer SA), a corporation organized under the laws of France ("Aventis"). 


RECITALS  


A.    Sepracor
and Aventis entered into that certain License and Assignment Agreement dated as of September 30, 1999 (the "1999
Agreement"). 


B.    Aventis
owns certain patents and patent applications, if any, as more particularly described on Schedule 1.21, which are the
foreign counterparts of the RPR Application (as defined in the 1999 Agreement) assigned to Sepracor pursuant to the 1999 Agreement and certain know-how relating to (+) zopiclone, the
racemate or the other enantiomer thereof, or metabolites of any of the foregoing. 


C.    Aventis
is willing to assign the above-referenced patents and patent applications, if any, to Sepracor and license to Sepracor exclusive rights under the above-referenced
know-how to make, have made, use, market, sell, offer for sale, have sold and distribute pharmaceutical products containing (+) zopiclone worldwide, on the terms and subject to the
conditions set forth in the 1999 Agreement and this Amendment, and Sepracor is willing to accept such assignment and license. 


D.    Sepracor
is willing to allow Aventis to assign certain rights under the 1999 Agreement to a third party. 


E.    Sepracor
and Aventis wish to amend certain provisions of the 1999 Agreement as set forth specifically in this Amendment. 


        NOW THEREFORE, in consideration of the mutual promises, covenants and agreements hereinafter set forth, the sufficiency of which is hereby
acknowledged, the parties to this Amendment mutually agree as follows: 


ARTICLE 1  


 DEFINITIONS  


        Capitalized terms used herein and not otherwise defined shall have the meanings given to them in the 1999 Agreement, as amended. 


ARTICLE 2  


 AMENDMENT OF 1999 AGREEMENT  


        Effective from and after the date hereof, subject to Article 5 of this Amendment, the 1999 Agreement shall be amended as follows: 



         2.1  All
references to the defined term "RPR" shall be replaced throughout the 1999 Agreement by the term "Aventis" as defined in this Amendment. 


         2.2  Article 1
(Definitions) is hereby amended as follows: 



      2.2.1  The
definition of "Agreement" is hereby amended and restated in its entirety as follows: 



        "Agreement" shall mean this License and Assignment Agreement, as amended. 




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      2.2.2  The
definition of the term "Product" is hereby amended by adding the phrase ", provided, however, that in the Additional Territory, the term "Product' shall not
include (±) zopiclone" to the end of such definition. 


      2.2.3  A
new definition of "Additional Patents" is hereby added as Section 1.21 as follows: 



        "Additional Patents" shall mean French Patent Application No. 91-00490 and PCT International Patent Application No.
PCT/FR92/00031 (collectively "Priority Applications"), and any patents and patent applications (whether pending, lapsed, or abandoned) in the Additional Territory claiming benefit of at least one
Priority Application, including without limitation, those described on Schedule 1.21 hereto, and any and all additions, divisions, continuations,
continuations-in-part, reissues, reexaminations, substitutions, supplemental protection certificates, extensions, patent term extensions, and renewals thereof, and patents
issued therefrom, which are the foreign counterparts of the RPR Application. 




      2.2.4  A
new definition of "Additional Territory" is hereby added as Section 1.22 as follows: 



        "Additional Territory" shall mean all of the countries in the world and their territories and possessions, other than the United States of
America and its territories and possessions. 




      2.2.5  A
new definition of "Amendment Date" is hereby added as Section 1.23 as follows: 



        "Amendment Date" shall mean July 2, 2004. 




      2.2.6  A
new definition of "Amendment Effective Date" is hereby added as Section 1.24 as follows: 



        "Amendment Effective Date" shall mean the date upon which the shareholders of Aventis SA shall have sold to Sanofi-Synthelabo, and
Sanofi-Synthelabo shall have purchased from the shareholders of Aventis SA, more than fifty percent (50%) of the shares and voting rights of Aventis SA in furtherance of the tender offer launched by
Sanofi-Synthelabo with respect to Aventis SA on the terms set forth in the "Note d'Information" that received approval of the French "Autorites des Marches Financiers", as the same may be amended. 





         2.3  The
existing Section 2.1 shall be made Section 2.1(a) and a new Section 2.1(b) is hereby added as follows: 



        Within
ten (10) Business Days of the Amendment Effective Date, Aventis shall assign all right, title and interest to the Additional Patents to Sepracor pursuant to an assignment
substantially in the form attached hereto as Schedule 2.1(b) and shall deliver such executed assignments to Sepracor within such ten
(10) Business Day period. Within twenty (20) Business Days of execution and delivery by Aventis of such assignment, up to date copies of all underlying prosecution history files of the
RPR Application and the Additional Patents not previously provided to Sepracor shall be transmitted to Sepracor. Sepracor may, at its sole discretion, attend to filing and recordation of such
assignments with the applicable patent office(s) in the applicable jurisdiction(s). 




         2.4  Section 2.2
is hereby amended by adding the following phrase at the end of the first sentence: 



        and,
as of the Amendment Effective Date, an exclusive license (exclusive even as to Aventis and its Affiliates except as provided under Section 2.9) under the RPR
Know-How and Improvements to develop, have developed, make, have made, use, market, sell, offer for sale, have sold and distribute Product in the Additional Territory. 




         2.5  Section 2.2
is hereby further amended by (i) adding the phrase "or, as of the Amendment Effective Date, the Additional Territory" after the term
"Territory" in the last sentence of Section 2.2 


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and
(ii) replacing the phrase "Section 2.7" with the phrase "Section 2.9" in the first parenthetical in the first sentence of Section 2.2. 



         2.6  Section 2.3
is hereby amended by adding the phrase "or, as of the Amendment Effective Date, the Additional Territory" after the term "Territory" in the last line
of Section 2.3 and by deleting the word "European" in Section 2.3. 


         2.7  Section 2.7
is hereby deleted in its entirety. 


         2.8  A
new Section 2.9 is hereby added to the Agreement as follows: 



        Aventis
hereby reserves, and nothing in this Agreement shall impair or limit, Aventis' or its Affiliates' or sublicensees' rights under the RPR Know-How and Improvements to
make or have made pharmaceutical products other than Product, or subject to Article 26, to otherwise utilize the RPR Know-How and Improvements for any purposes which are not
expressly and exclusively granted to Sepracor pursuant to the terms of this Agreement, including without limitation for the purposes of meeting and otherwise fulfilling all of Aventis' (and its
Affiliates' and sublicensees') legal, regulatory and contractual obligations with respect to (±) zopiclone in the Additional Territory. 




         2.9  Section 3.2.4
is hereby deleted in its entirety. 


       2.10  Section 5.2
is hereby amended by adding the phrase, "in the Territory" after the phrase "to avoid loss of any rights" in the first sentence of
Section 5.2. 


       2.11  Section 5.3
is hereby deleted in its entirety, and a new Section 5.3 is added in lieu thereof which reads in its entirety as follows: 



        After
the Effective Date, Aventis shall provide Sepracor full access to the information referenced in Section 2.3 hereof, and shall use good faith reasonable efforts in fully
cooperating with Sepracor in order to enable Sepracor to obtain Regulatory Approval of Products. At Sepracor's request, Aventis shall disclose to Sepracor in writing, or via mutually acceptable
electronic media, copies or reproductions of all written RPR Know-How reasonably available to Aventis or its Affiliates in order to enable Sepracor to obtain Regulatory Approval of
Products. In addition, during the term of this Agreement, Aventis shall promptly disclose to Sepracor in writing, or via mutually acceptable electronic media, on an ongoing basis copies or
reproductions of all Improvements that are reasonably necessary to research, develop, register, manufacture, market, use or sell Product. Such Improvements shall be automatically deemed to be within
the scope of the licenses granted herein without payment of any additional compensation. Sepracor shall have the right to use for all purposes in connection with Regulatory Approval (or other
regulatory approval in the Additional Territory) or any regulatory application for Product all RPR Know-How and other information disclosed pursuant to this Section and under this
Agreement. Upon Sepracor's request, Aventis shall provide reasonable technical assistance to enable Sepracor to utilize RPR Know-How to
obtain Regulatory Approval of Products, and from time to time at Sepracor's reasonable request, Aventis shall use good faith reasonable efforts to assist Sepracor in providing responses to questions
that may be raised by regulatory authorities in connection with Sepracor's applications for Regulatory Approval of Products. Sepracor shall be solely responsible for obtaining all Regulatory Approvals
(and other regulatory approvals in the Additional Territory) related to the Product. 




       2.12  Article 6
(Infringement) is hereby amended by adding the phrase "or the Additional Patents, as applicable" after the term "RPR Applications" each time such term
appears in Article 6. 


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       2.13  Article 8
(Term) is hereby deleted in its entirety, and a new Article 8 is added in lieu thereof which reads in its entirety as follows: 



 ARTICLE 8—TERM  




        This Agreement will commence as of the Effective Date and, unless sooner terminated as provided hereunder, shall terminate on the expiration of the royalty
obligations of Article 3, after which time Sepracor will have a fully paid-up, royalty-free and irrevocable exclusive license under RPR Know-How and
Improvements to develop, have developed, make, have made, use, market, sell, offer for sale, have sold and distribute Product in the Territory and the Additional Territory. Notwithstanding the
foregoing, if Sepracor breaches its obligations under Section 2.4, then this Agreement shall terminate ten (10) years from the Effective Date, or thirty (30) days after Aventis
gives notice to Sepracor of such breach, as applicable. Upon any such early termination of this Agreement, all rights to RPR Know-How and Improvements licensed hereunder to Sepracor shall
revert to Aventis, and Sepracor and its Affiliates and Licensees shall make no further use of the same. 


       2.14  Section 10.1.5
is hereby amended by adding the following clause at the end of such Section 10.1.5: 



        As
of the Amendment Date, Aventis' right, title and interest in the Additional Patents, or RPR Know-How as it relates to (+) zopiclone, in the Additional Territory are not
assigned, transferred, or conveyed to a Third Party or, to Aventis' knowledge, otherwise encumbered by a Third Party; 




       2.15  Section 10.1.6
is hereby amended by adding the following clause at the end of such Section 10.1.6: 




As
of the Amendment Date, Aventis is the sole and exclusive owner of the Additional Patents and, to Aventis' knowledge, the sole and exclusive owner or licensee of the RPR Know-How as it
relates to (+)zopiclone, all of which to the knowledge of Aventis, are free and clear of any liens, charges and encumbrances and, to the knowledge of Aventis, except for Aventis' Affiliates, no other
person, corporate or other private entity or governmental entity or subdivision thereof has, or shall have, any claim of control with respect to the Additional Patents, and RPR Know-How as
it relates to (+) zopiclone, in the Additional Territory; 





       2.16  Section 10.1.7
is hereby amended by adding the following clause at the end of such Section 10.1.7: 



        As
of the Amendment Date, in the Additional Territory, there are no claims, judgments or settlements against or owed by Aventis pending or, to the knowledge of Aventis, threatened with
respect to the Additional Patents and the RPR Know-How, as they relate to Zopiclone Technology or Product; 




       2.17  Section 10.1.10
is hereby amended by adding the following clause at the end of such Section 10.1.10: 



        As
of the Amendment Date, Aventis has not performed any searches to determine if, and has no actual knowledge that, the development, manufacture, use, distribution, marketing, promotion
and sale of Compound in the Additional Territory interferes or infringes on any intellectual property rights owned or possessed by any Third Party; and 




       2.18  A
new Section 10.1.12 is hereby added as follows: 




Aventis
and its Affiliates (and any employee, consultant, or agent thereof) shall not directly or indirectly take any action, or cause any action to be taken, between the Amendment Date and 




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the
Amendment Effective Date that is inconsistent with or would alter the correctness of Aventis' representations and warrants in this Agreement. 





       2.19  Section 10.3
is hereby deleted in its entirety and hereby replaced with a new Section 10.3 as follows: 



        During
the term of this Agreement, Aventis covenants that neither Aventis nor any of its Affiliates will develop, use, market, promote, sell or distribute (or agree with any third party
to do any of the foregoing) in the Territory any product containing Compound, the racemate or the other enantiomer thereof, as an active ingredient. 




       2.20  Article 11
(Adverse Events) is hereby amended and restated in its entirety as follows: 



        Following
the Effective Date, Sepracor shall be solely responsible for complying with all legal and/or regulatory obligations in the Territory regarding the reporting of adverse events
related to Product and following the Amendment Effective Date, Sepracor shall be solely responsible for complying with all legal and/or regulatory obligations in the Additional Territory regarding the
reporting of adverse events related to Product. 




       2.21  Section 12.1
is hereby amended by adding the phrase "or the Additional Territory" after the term "Territory" in Section 12.1. 


       2.22  Article 15
(Notices) is hereby amended by replacing the existing notice address for Aventis with the following address: 




Aventis
Pharma SA 


c/o
Aventis Pharmaceuticals Inc.

Mail Stop: BX2-716A

200 Crossing Boulevard, P.O. Box 6890

Bridgewater, NJ 08807-0890

Attn: Vice President Business Development/TL&A

Facsimile: (908) 231-4480 





       2.23  Section 23.2
is hereby amended by deleting the phrase "in the Territory," in the third line of Section 23.2. 


       2.24  A
new Article 26 is hereby added as follows: 



 ARTICLE 26—INFORMATION  




        From and after the Amendment Effective Date, Aventis shall ensure that Aventis and its Affiliates (and employees, consultants, and agents thereof) do not,
directly or indirectly, use or otherwise place in the public domain, any information owned by, or in the possession or control of (including without limitation information relating to Compound or any
metabolites thereof provided by Sepracor to Aventis or its Affiliates), Aventis or its Affiliates that is not in the public domain, specifically relating to Compound (to the extent such exists as of
the Amendment Date) or (±) zopiclone, or any metabolite of either, including but not limited to information relating to research, development, pharmacological
characteristics, clinical effect, clinical trials, manufacture, marketing, commercialization, distribution, importation, exportation, cost, pricing, supply, sales, sales support, or use thereof;  provided, however, that in the Additional Territory, any current or future employees and agents of
Aventis or its Affiliates involved in research, development, manufacture, sales, marketing, promotion, medical communications, or regulatory maintenance of pharmaceutical products containing
(±) zopiclone in the Additional Territory, shall be free to use any Aventis information specifically relating to (±) zopiclone
solely in connection with those activities in the Additional Territory. For purposes of clarity, in no event shall the foregoing prohibit or in any way limit (i) the rights of Aventis or its
Affiliates to use, directly or 


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indirectly,
such information in connection with any actual or proposed sale, assignment or other transfer of rights in (±) zopiclone from Aventis or its Affiliates to
a Third Party (a "Transferee") or (ii) the rights of any Transferee to use, directly or indirectly, such information. Notwithstanding anything to the contrary contained herein,
(i) Aventis, its Affiliates and any employee, agent, or consultant of Aventis, shall be allowed to use, directly or indirectly, such information as required by any applicable law or any
applicable regulatory authority or other governmental entity in the Additional Territory and (ii) the provisions of this Article 26 shall not exclude use of any information independently
developed by Sanofi-Synthelabo or its Affiliates prior to the Amendment Effective Date. 



       2.25  The
following schedules are hereby added as schedules to the 1999 Agreement: 



    2.25.1  Schedule 1.21
attached hereto is hereby added to the 1999 Agreement as Schedule 1.21. 


    2.25.2  Schedule 2.1(b)
attached hereto is hereby added to the 1999 Agreement as Schedule 2.1(b). 




       2.26  Except
as otherwise set forth herein, the 1999 Agreement shall remain in full force and effect. 


ARTICLE 3  


 ADDITIONAL OBLIGATIONS OF AVENTIS  


         3.1  Aventis
shall, within twenty (20) Business Days of the Amendment Effective Date, deliver copies of the documents described on Schedule 3.1 hereto to
Sepracor, to the extent Aventis has not previously delivered copies of such documents, solely to the extent such documents are within the possession or control of Aventis (or its Affiliates, agents,
employees or consultants) on the Amendment Date and are legally permitted to be disclosed. 



         3.2  Within
ten (10) Business Days after the Amendment Date, Aventis shall provide Sepracor with (i) a current docket listing and description of the status of
each of the Additional Patents and copies of all related outstanding actions, if any and (ii) a copy of the prosecution history of any pending applications among the Additional Patents, if any.
From and after the Amendment Date until the earlier of (x) the Amendment Effective Date and (y) the date, if any, that it is determined by Aventis and communicated to Sepracor that the
Amendment Effective Date will not occur, Aventis shall conduct maintenance and prosecution of the Additional Patents consistent with Aventis' past practice and otherwise in the ordinary course of
business, provided, however, that Aventis shall timely pay any taxes, annuities, or maintenance fees due
between the Amendment Date and the Amendment Effective Date. 


ARTICLE 4  


 CONSENT TO ASSIGNMENT  


         4.1  Pursuant
to the terms of Section 18.1 of the 1999 Agreement, Sepracor hereby consents to the assignment by Aventis of Aventis' rights, in whole or in part, under
Article 3 and Article 4 of the 1999 Agreement, as amended by this Amendment, including, without limitation, its right to receive Royalties pursuant to Section 3.1, its right to
receive Royalty Statements pursuant to Section 4.1 and its right to conduct audits pursuant to Section 4.5. 


         4.2  In
connection with the foregoing consent to assignment, Aventis shall have the right to provide complete and unredacted copies of the 1999 Agreement and this Amendment
to any potential assignee, provided, however, that such potential assignee agrees to be bound by confidentiality provisions substantially similar to those set forth in Article 7 of the 1999
Agreement. 


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ARTICLE 5  


 EFFECTIVE DATE  


         5.1  Except
with respect to the provisions of Sections 2.18, 2.22, 3.2 and 4.2 of this Amendment which shall be effective as of the Amendment Date, this Amendment shall
become effective on the date upon which the shareholders of Aventis SA shall have sold to Sanofi-Synthelabo, and Sanofi-Synthelabo shall have purchased from the shareholders of Aventis SA, more than
fifty percent (50%) of the shares and voting rights of Aventis SA in furtherance of the tender offer launched by Sanofi-Synthelabo with respect to Aventis SA on the terms set forth in the "Note
d'Information" that received approval of the French "Autorites des Marches Financiers", as the same may be amended (the "Purchase Event"). Notwithstanding the foregoing, to the extent an event occurs
which would require payment of $5,000,000 under Section 3.2.4 of the 1999 Agreement following the Amendment Date, but prior to the Amendment Effective Date, no such payment shall be made unless
it is determined by Aventis and communicated to Sepracor that the Amendment Effective Date will not occur (the date such notice is communicated, the "Termination
Date"), in which event such payment shall be made within (10) Business Days following the Termination Date. 


[NO FURTHER TEXT ON THIS PAGE]  


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IN WITNESS WHEREOF, the Parties have executed this Amendment as of the date first above written. 



	AVENTIS PHARMA SA
	

By:	
 	

/s/  DIRK OLDENBURG      

	Name:	 	Dirk Oldenburg
	Title:	 	General Counsel
	
SEPRACOR INC.
	

By:	
 	

/s/  WILLIAM E. YELLE      

	Name:	 	William E. Yelle
	Title:	 	VP, Business Development










SCHEDULE 1.21  


 ADDITIONAL PATENTS  



	Country
 
	 	Application Date
	 	Application Number
	 	Grant date
	 	Patent Number
	 	Expiration date

	AR	 	16/01/1992	 	321649	 	31/05/1995	 	248024	 	31/05/2010
	AT	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	E 121089	 	16/01/2012
	AU	 	16/01/1992	 	92 12264	 	07/01/1997	 	671797	 	16/01/2012
	BD	 	15/01/1992	 	92 5	 	14/01/1993	 	1002434	 	17/01/2007
	BE	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	BY	 	17/05/1994	 	1681	 	14/05/1997	 	1854	 	16/01/2012
	CA	 	16/01/1992	 	2099782	 	03/12/2003	 	2099782	 	16/01/2012
	CH	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	CZ	 	16/01/1992	 	93 1380	 	02/04/1996	 	281011	 	16/01/2012
	DE	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	69202060.8	 	16/01/2012
	DK	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	ES	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	2071486	 	16/01/2012
	FI	 	16/01/1992	 	93 3248	 	14/11/1997	 	100331	 	16/01/2012
	FR	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	GB	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	GR	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	HU	 	16/01/1992	 	P93 02063	 	02/10/2000	 	218928	 	16/01/2012
	IE	 	16/01/1992	 	92 126	 	21/11/1995	 	66110	 	16/01/2012
	IL	 	16/01/1992	 	100677	 	28/02/1996	 	100677	 	16/01/2012
	IT	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	LU	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	MA	 	15/01/1992	 	22677	 	01/10/1992	 	22392	 	15/01/2012
	MX	 	16/01/1992	 	92 180	 	12/08/1994	 	175679	 	16/01/2012
	NG	 	16/01/1992	 	92 15	 	30/07/1992	 	RP 11252	 	16/01/2012
	NL	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	NO	 	16/01/1992	 	93 1919	 	08/01/1997	 	179911	 	16/01/2012
	NZ	 	15/01/1992	 	241313	 	20/07/1993	 	241313	 	15/01/2012
	OA	 	16/01/1992	 	60387	 	15/04/1994	 	9807	 	16/01/2012
	PH	 	16/01/1992	 	43784	 	23/12/1997	 	30982	 	23/12/2014
	PK	 	16/01/1992	 	92 22	 	19/12/1993	 	132928	 	16/01/2008
	PL	 	16/01/1992	 	P 299834	 	01/02/1995	 	166976	 	16/01/2012
	PT	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	RU	 	16/01/1992	 	93 051787	 	10/05/1998	 	2110519	 	16/01/2012
	SE	 	16/01/1992	 	92903994.9-2101	 	12/04/1995	 	609210	 	16/01/2012
	SK	 	16/01/1992	 	93 719	 	18/02/1998	 	279060	 	16/01/2012
	TN	 	17/01/1992	 	92 004	 	06/10/1992	 	16531	 	17/01/2012
	YU	 	17/01/1992	 	92P 55	 	11/06/2002	 	48 878	 	17/01/2012
	ZA	 	15/01/1992	 	92 302	 	28/10/1992	 	92 302	 	15/01/2012










SCHEDULE 2.1(b)  


 ASSIGNMENT OF ADDITIONAL PATENTS  


ASSIGNMENT  


WHEREAS,
Aventis Pharma SA ("Aventis"), a French corporation having a place of business at 20, avenue Raymond-Aron, F-92160 Antony, France, owns, by assignment, all right,
title, and interest in and to French Patent Application Serial No. 91-00490, entitled "Optically Active 5H-Pyrrolo[3,4-b] pyrazine Derivative,
Its Preparation and Pharmaceutical Compositions Containing Same", and PCT International Patent Application No. PCT/FR92/00031, and any and all non-United States patents or patent
applications related to either of the aforesaid applications, including without limitation the patents and patent applications listed in Attachment A, and any invention described therein (collectively
hereinafter "Eszopiclone Foreign Patents"); and 


WHEREAS,
Sepracor Inc. ("Sepracor"), a Delaware corporation having a place of business at 84 Waterford Drive, Marlborough, Massachusetts USA 01752, is desirous of obtaining Aventis' entire
right, title, and interest in, to, and under the Eszopiclone Foreign Patents, and Aventis desires to assign to Sepracor its entire right, title and interest in the same. 


NOW
THEREFORE, be it known that, for good and valuable consideration to Aventis, the receipt and sufficiency of which is hereby acknowledged, Aventis hereby sells, assigns, transfers, and sets over to
Sepracor, its lawful successors and assigns, Aventis' entire right, title, and interest in, to, and under Eszopiclone Foreign Patents (all of which are hereby incorporated by reference as if fully set
forth herein), any inventions described or claimed therein, all rights to claim priority on the basis of any Eszopiclone Foreign Patents, and all applications for Letters Patent that may be filed for
such invention in any country other than the United States and all Letters Patent that may be granted on any such application, and any and all extensions, supplemental protection certificates,
additions, divisions, substitutions, and renewals of any of the foregoing, in each case, as fully and entirely as the same would have been held and enjoyed by Aventis if this assignment had not been
made. 


AND,
AVENTIS HEREBY further convenants that Aventis shall, from time to time after the date hereof upon the request of Sepracor, execute and deliver to Sepracor such further conveyance instruments or
confirmatory assignments as may be necessary or desirable to evidence more fully the transfer of ownership of all Eszopiclone Foreign Patents to Sepracor, or the original ownership of all the
Eszopiclone Foreign Patents on the part of Aventis, to the fullest extent possible, and to perform any other acts deemed necessary to carry out the intent of this instrument. 


AND,
AVENTIS HEREBY authorizes and requests that any official of any country whose duty it is to issue patents or other evidence or forms of industrial property protection on applications as
aforesaid, to issue all patents or Letters Patents for this invention to Sepracor, its successors and assigns, in accordance with the terms of this instrument. 








        IN
WITNESS WHEREOF, Aventis has caused its authorized representative to execute this Assignment 



	AVENTIS PHARMA SA	 	 	 	 
	

By:	
 	

 	
 	

Date:	
 	

 
	 	 	
	 	 	 	

	Name:	 	 	 	 	 	 
	Title:	 	 	 	 	 	 




 




	State of	 	)	 	 
	 	 	)	 	SS.:
	County of	 	)	 	 





        On this            day
of                        , 2004, before me, a Notary Public in and for the State and County aforesaid, personally
appeared                        ,
to me known and known to me to be the person of that name, who signed and sealed the foregoing instrument, and he acknowledged the same to be his free act and deed. 



	 	 	
	 	,
	 	 	Notary Public.










ATTACHMENT A  



	1.	 	French Patent Application No. 91-00490, filed 17 January 1991;
	2.	 	PCT International Patent Application No. PCT/FR92/00031, filed 16 January 1992;
	3.	 	European Patent Application No. 92903994.9-2101, filed 16 January 1992;
	4.	 	Argentinian Patent No. 248024, granted 31 May 1995;
	5.	 	Austrian Patent No. E 121089, granted 12 April 1995;
	6.	 	Australian Patent No. 671797, granted 7 January 1997;
	7.	 	Bangladesh Patent No. 1002434, granted 14 January 1993;
	8.	 	Belgian Patent No. 609210, granted 12 April 1995;
	9.	 	Belarus Patent No. 1854, granted 14 May 1997;
	10.	 	Canadian Patent No. 2,099,782, granted 3 December 2003;
	11.	 	Swiss Patent No. 609210, granted 12 April 1995;
	12.	 	Czech Republic Patent No. 281011, granted 2 April 1996;
	13.	 	German Patent No. 69202060.8, granted 12 April 1995;
	14.	 	Danish Patent No. 609210, granted 12 April 1995;
	15.	 	Spanish Patent No. 2071486, granted 12 April 1995;
	16.	 	Finnish Patent No. 100331, granted 14 November 1997;
	17.	 	French Patent No. 609210, granted 12 April 1995;
	18.	 	British Patent No. 609210, granted 12 April 1995;
	19.	 	Greek Patent No. 609210, granted 12 April 1995;
	20.	 	Hungarian Patent No. 218928, granted 2 October 2000;
	21.	 	Ireland Patent No. 66110, granted 21 November 1995;
	22.	 	Israeli Patent No. 100677, granted 28 February 1996;
	23.	 	Italian Patent No. 609210, granted 12 April 1995;
	24.	 	Japanese Patent Application No. 1992-504006, filed 16 January 1992;
	25.	 	Luxembourg Patent No. 609210, granted 12 April 1995;
	26.	 	Moroccan Patent No. 22392, granted 1 October 1992;
	27.	 	Mexican Patent No. 175679, granted 12 August 1994;
	28.	 	Nigerian Patent No. RP 11252, granted 30 July 1992;
	29.	 	Netherlands Patent No. 609210, granted 12 April 1995;
	30.	 	Norwegian Patent No. 179911, granted 8 January 1997;
	31.	 	New Zealand Patent No. 241313, granted 20 July 1993;
	32.	 	OAPI Patent No. 9807, granted 15 April 1994;
	33.	 	Philippine Patent No. 30982, granted 23 December 1997;
	34.	 	Pakistan Patent No. 132928, granted 19 December 1993;
	35.	 	Polish Patent No. 166976, granted 1 February 1995;
	36.	 	Portuguese Patent No. 609210, granted 12 April 1995;
	37.	 	Russian Federation Patent No. 2110519, granted 10 May 1998;
	38.	 	Swedish Patent No. 609210, granted 12 April 1995;
	39.	 	Slovakian Patent No. 279060, granted 18 February 1998;
	 	 	 









	40.	 	Tunisian Patent No. 16531, granted 6 October 1992;
	41.	 	Yugoslavian Patent No. 48 878, granted 11 June 2002; and
	42.	 	South African Patent No. 92 302, granted 28 October 1992.









SCHEDULE 3.1  


 ADDITIONAL DOCUMENTATION  


        Draft or completed reports of any clinical or nonclinical studies or experiments not published or previously provided to Sepracor as of the Amendment Effective
Date, including postmarketing reviews and safety surveillance reports relating to Compound, the racemate, the other enantiomer thereof, or metabolites of any of the foregoing. 











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Exhibit 10.1


AMENDMENT AND PATENT ASSIGNMENT AGREEMENT