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Exhibit 10.16    
    


***Text Omitted and Filed Separately

Pursuant to a Confidential Treatment Request

Under C.F.R.§§200.80(b)(4) and Rule 406

of the Securities Act of 1933, as amended.  


 Supplementary Agreement  


 to the License Agreement dated September 1, 2006 between Aetas and NovaCardia  


With
reference to the license agreement ("License Agreement") for K201 dated September 1, 2006 by and between Aetas Pharma Co., Ltd. ("Licensor") and NovaCardia Inc. ("Licensee"),
Licensor and Licensee hereby enter into this Supplementary Agreement ("Supplementary Agreement") as of January 5, 2007 in order to supplement and amend the License Agreement to incorporate the
Products for oral administration further to the existing intravenous administration. 


1.    General    


	1.1
	For
avoidance of doubt, any amendment made herein shall apply to any and all provisions of the License Agreement. 





2.    Definitions (Article 1)    


	2.1
	The
definition of the "API" shall amend as follows: 



Article 1 (3) "API" shall mean the active pharmaceutical ingredient comprising the Licensed Compound, which shall only be used for making
Product for intravenous (IV) administration and/or oral administration in the Field for the Territory hereunder. 



	2.2
	The
definition of the "Filed" shall amend as follows: 



Article 1 (9) "Field" shall mean the treatment and/or prevention of cardiac arrhythmia including atrial fibrillation and/or
[. . .***. . .] in humans for the intravenous (IV) administration, and of all cardiac diseases for the oral
formulation. 



	2.3
	The
definition of the "Patents" shall amend as follows: 



Article 1 (20) "Patents" shall mean any and all patent applications and patents that Licensor Controls as of the Effective Date or during
the Term, which would, but for the grant of rights to practice such patent applications or patents, be infringed by the manufacture, use, sale, offer for sale or import of Products or API in the
Territory in the Field for intravenous (IV) administration and/or oral administration, including, 


***Confidential Treatment Requested



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without
limitation, any substitutions, extensions, registrations, confirmations, reissues, re-examinations, renewals and similar filings with respect to any patent and any
provisionals, converted provisionals, continued prosecution applications, continuations, divisionals and continuations-in-part of any patent application. The Patents as of the
Effective Date are set forth on Exhibit A, which Patents may be added by mutual agreement from time to time to Exhibit A as may be arising out of any result relating to the Product or
API made by Licensor hereunder. 



	2.4
	The
definition of the "Products" of the License Agreement shall amend as follows: 



Article 1 (25) "Products" shall mean any and all pharmaceutical product formulations for intravenous (IV) administration and/or
oral administration in the Field for the Territory containing the Licensed Compound as an active ingredient. 



	2.5
	The
definition of the "Subject Right" shall amend as follows: 



Article 1 (28) "Subject Right" shall mean (a) any license or other right to the Licensed Compound, Products, Patents and Technical
Information for any or all other cardiac uses outside of the Field, and/or (b) any license or other right to the Licensed Compound, Patents and Technical Information for pharmaceutical product
formulations for any or all routes of administration (other than intravenous (IV) and oral administration), including, but not limited to sublingual, transdermal, intramuscular, subcutaneous
and inhaled administrations, for any or all uses. 




3.    GRANTS (Article 2)    


	3.1
	Article 2
(2) of the License Agreement shall amend as follows:



	2.
	Licensee
hereby agrees to use its commercially reasonable efforts to develop, register and market Product, as it makes for its products having a similar market potential, in any
country of the Territory to maximize the potential of Product. For the purpose hereof, Licensee shall have material obligations in the development to; i) commence the first intravenous (IV)
administration to the first subject in a Phase 1 clinical study [. . .***. . .] from the Effective Date,
ii) commence the first iv administration to the first patient in the phase 3 clinical study [. . .***. . .]
from the Effective Date, and iii) commence the first oral administration to the first subject in a Phase 1 clinical study
[. . .***. . .] from the Effective Date of the Supplementary Agreement. 
***Confidential Treatment Requested








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3A.    TECHNICAL ASSISTANCE OF LICENSOR; RESEARCH (Article 3)    


Article 3A.1
Article 3 (3) of the License Agreement shall amend as follows: 



	3.
	Recognizing
the rights as granted to Licensee under Article 2, supply of any material including but not limited to API and Products necessary for gaining the Regulatory Approval
and marketing the Product by Licensee hereunder shall make available under Licensee's sole responsibility. Notwithstanding the foregoing in this Article 3(3), both parties shall discuss in good
faith and agreed upon any appropriate arrangements, where Licensor may supply Licensee, at reasonable consideration, with samples for clinical testing and bulk materials of the Products for the
research and development of formulations for iv and/or oral administration. In the event that Licensor is unable to supply such samples or materials of the Product appropriately, Licensor may use its
commercially reasonable efforts to assist Licensee at Licensee's expenses to find any contract-manufacturer for Licensee. 




4.    Fees and Royalties (Article 4)    


	4.1
	In
addition to the Fees to be paid by Licensee to Licensor under Article 4 (1) i, ii and iii of the License Agreement, the provision "iv" shall be inserted after "iii",
and Licensee shall, following the occurrence of each of the events below, pay to Licensor the fees or milestone payments set forth below:



	iv
	Milestone
Schedule, oral administration:



	a.
	US$500,000
upon the signing of this Supplementary Agreement; and



	b.
	US$[. . .***. . .]
upon
[. . .***. . .] of the Product in the Territory



	c.
	US$[. . .***. . .]
upon
[. . .***. . .] of the Product in the Territory



	d.
	US$[. . .***. . .]
upon
[. . .***. . .] for a Product in the Territory



	e.
	US$[. . .***. . .]
upon
[. . .***. . .] for a Product in the Territory









	4.2
	For
avoidance of doubt, all payments under Article 4 (1) i, ii and iii shall apply only to the occurrence with respect to Product for intravenous
(IV) administration and Article 4 (1) iv shall apply only to the occurrence with respect to Product for oral administration. 
***Confidential Treatment Requested





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	4.3
	For
avoidance of doubt, the language of "total annual Net Sales of all Products in the Territory" in Article 4 (2) means the "total annual Net Sales of all Products not
only for intravenous (IV) administration but also for oral administration in all countries in the Territory". 




5.    Effective Date    


	5.1
	This
Supplementary Agreement shall become effective as of December 1, 2006 and shall remain effective until the expiration or termination of the License Agreement. 



6.    Effectiveness of the License Agreement    


	6.1
	Except
for the terms and conditions as amended or supplemented herein, all other terms and conditions of the License Agreement and its related agreements shall remain in full force
and effect. 



7.    Titles    


	7.1
	Titles
in this Supplementary Agreement have been inserted for convenience only and shall have in no way be used in the interpretation hereof. 



In
Witness Whereof, the parties hereto have caused this Supplementary Agreement to be executed by their duly authorized representatives. 



	Aetas Pharma Co., Ltd.	 	NovaCardia, Inc.
	

By	
 	

/s/ Toru Kaneko
 Toru Kaneko

President	
 	

By	
 	

/s/ Randall E. Woods
 Randall E. Woods

President & CEO
	

Date	
 	

18 January 2007
	
 	

Date	
 	

15 January 2007





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Exhibit 10.16