EX-10.68






June 16, 2008



	 	 	 	 	 
	GlaxoSmithKline
	 	 	 	 
	2301 Renaissance Boulevard

	Building #510
RN0420
	 	 	 	 
	King of Prussia, Pennsylvania 19406

	Attn:
	 	Vinod Ramachandran, Ph.D.






Alliance Manager



Re: Third Extension of the Research Term with respect to CENP-E under that certain Collaboration
and License Agreement by and between Glaxo Group Limited, a GlaxoSmithKline company,
(“GSK”) and Cytokinetics, Inc. (“CK”), dated June 20, 2001, as amended (the
“Collaboration Agreement”)



Dear Vinod:



Pursuant to this letter amendment to the Collaboration Agreement (the “Amendment”), GSK and
CK desire to further extend the Research Term solely with respect to the Mitotic Kinesin Target
known as CENP-E, and on the terms set forth herein.



Now therefore, GSK and CK agree, effective as of June 19, 2008, as follows:




	 	1.	 	All capitalized terms not defined herein shall have the meaning ascribed to them in
the Collaboration Agreement.






	 	2.	 	Notwithstanding GSK’s obligation to notify CK in writing of its exercise of its
option to extend the Research Term under Section 2.8.1 of the Collaboration Agreement, the
Research Term is hereby extended for an additional one-year period to expire on June 19,
2009 solely with respect to CENP-E to allow for the conduct of Research Program activities
directed to CENP-E, in accordance with the terms and conditions of the Collaboration
Agreement. GSK shall have no further right to extend the Research Term, unless otherwise
expressly agreed in writing by the Parties.






	 	3.	 	GSK shall have no further right to extend its exclusivity rights under Section 4.2 of
the Collaboration Agreement with respect to CENP-E, unless otherwise expressly agreed in
writing by the Parties.






	 	4.	 	The Research Plan for the extended Research Term is attached as Exhibit A hereto.






	 	5.	 	Notwithstanding Section 2.8.1 of the Collaboration Agreement, GSK has no obligation
to fund any CK FTEs during this extension of the Research Term for CENP-E.






	 	6.	 	Each Party agrees to execute, acknowledge and deliver such further instruments, and
to do all such other acts, as may be necessary or appropriate in order to carry out the
purposes and intent of this Amendment.






	 	7.	 	Except as specifically modified or amended hereby, the Collaboration Agreement shall
remain in full force and effect and, as modified or amended, is hereby ratified, confirmed
and approved. No provision of this Amendment may be modified or amended except expressly
in a writing signed by both Parties, nor shall any terms be waived except expressly in a
writing signed by the Party charged therewith. This Amendment shall be governed in
accordance with the laws of the State of New York, without regard to principles of
conflicts of laws.





If the foregoing is acceptable, please have an authorized representative of GSK countersign this
Amendment where indicated below. Please return one fully executed original to my attention.



Sincerely,



/s/ Michael S. Rabson

Michael S. Rabson, Ph.D.

Sr. Vice President, Business Development & Legal Affairs, and General Counsel



Cytokinetics, Inc.



Agreed and accepted:



GLAXO GROUP LIMITED



/s/ Paul Williamson


For and on behalf of


Edinburgh Pharmaceutical Industries Limited


Corporate Director



/s/ Paul Blackburn


For and on behalf of


Glaxo Group Limited





Corporate Director



18/6/08



	 	 	 
	cc:

	 	Adrian Rawcliffe, SVP WW Business Development, GlaxoSmithKline

Lisa A. DeMarco, Esq., VP & Associate General Counsel, GlaxoSmithKline,

R&D Legal Operations











1






Exhibit A




Research Plan 




[****]





2






[***]





3