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Exhibit 10.11    
    


SCHERING CORPORATION

2000 Galloping Hill Road        Kenilworth, N.J. 07033


Telephone: (908) 298-4000


Confidential
Materials omitted and filed separately with the

Securities and Exchange Commission. Asterisks denote such omissions. 


November
30, 2004 


Mr.
Arthur Hiller

Senior Vice President, Sales & Marketing

Millennium Pharmaceuticals, Inc.

40 Landsdowne Street

Cambridge, Massachusetts 02139-4815 



	Re:
	Additional
Field Force Agreement — Further Amendment to Extend the Decision to Renew Joint Funding for 2005 




Dear
Mr. Hiller: 


        I
am writing with regard to the Addendum, effective June 1, 2003, to the 1995 Collaboration Agreement among Millennium Pharmaceuticals, Inc., Schering Corporation and Schering-Plough,
Ltd., including as such Addendum was previously amended (the "Additional Field Force Agreement"). 


        As
you are aware, Schering and Millennium previously agreed to extend until [**] the deadline for a decision by the JSC on whether or not to continue joint
funding of the Additional Field Force for the 2005 calendar year. In order to ensure that the parties reach a fully informed decision that reflects the best interests of both companies and the
product, Schering is willing to agree to a further extension of the deadline until the JSC meeting scheduled for December 6, 2004, as follows. 


        Any
capitalized terms that are not expressly defined herein shall have the meaning set forth in the Additional Field Force Agreement. 


        The
parties hereby agree to the following additional amendments to the Additional Field Force Agreement in connection with the deadline to renew joint funding obligations for 2005
pursuant to Sections 4.1 and 2.4 of the Additional Field Force Agreement: 



	(1)
	the
date for the 2005 renewal decision is further extended from [**] to not later than [**]. However, nothing in the Additional Field
Force Agreement or this Letter shall be construed as obligating either party to consider or agree to any further extension of this deadline.



	(2)
	In
the event the JSC elects not to renew the Additional Field Force Agreement for 2005, the sixty (60) day period referred to in Section 4.4 of the Additional Field Force Agreement
(and notwithstanding any previous amendments to such period) shall be replaced by the period beginning on the date of such JSC decision and ending on January 14, 2005.



	(3)
	The
parties agree that Schering will continue to share an equal (50:50) portion of any Additional Field Force Expenses incurred with respect to members of the Additional Field Force
that continue to be employed by Millennium during the period beginning on January 1, 2005 and ending on January 14, 2005.



	(4)
	In
the event the JSC elects to renew the Additional Field Force Agreement for 2005, the annual budget for Additional Field Force Expenses for 2005 to be agreed to under Section 3.4.2
of the Additional Field Force Agreement, shall be agreed upon by the JSC within sixty (60) days after such decision. 




        All
other terms and conditions of the Additional Field Force Agreement will remain in full force and effect. 










        Please
indicate your agreement to this Amendment by signing below and returning one fully executed original to my attention. 



	 	Regards,

SCHERING-CORPORATION

on behalf of itself and its Affiliate Schering-Plough Ltd.
	

 	

/s/ Margriet Gabriel-Regis
 Margriet Gabriel-Regis

Vice President





AGREED:

MILLENNIUM PHARMACEUTICALS, INC. 



	By:	/s/ A. J. Hiller
	 
	

Name(print):	

A. J. Hiller
	

 
	

Title:	

Senior Vice President
	

 













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Exhibit 10.11