EX-24 3 attach_2.htm

POWER OF ATTORNEY





KNOWN ALL MEN BY THESE PRESENTS, that the undersigned hereby constitutes and appoints CRAIG

L. SLUTZKIN as his/her true and lawful attorney-in-fact and agent for him/her and in his/her

name, place and stead, in any and all capacities, to sign any and all documents relating to

any and all Securities and Exchange Commission filings which may be required, granting unto

said attorney-in-fact and agent full power and authority to do and perform each and every act

and thing requisite and necessary to be done in and about the premises, as fully to all

intents and purposes as he/she might or could do in person, thereby ratifying and confirming

all that said attorney-in-fact may lawfully do or cause to be done by virtue hereof.



This power shall continue in effect until terminated in writing.





By: /s/ Philippe O. Chambon

Philippe O. Chambon



By: /s/ Jeani Delagardelle

Jeani Delagardelle



By: /s/ Ronald Hunt

Ronald Hunt





Dated: September 29, 2006