STOCKHOLDER WAIVER



 Exhibit 4.1 
 ICAGEN, INC. 
 STOCKHOLDER 
 WAIVER, AMENDMENT AND TERMINATION AGREEMENT 
  

 WHEREAS, Icagen, Inc., a Delaware corporation (the “Company”), and certain stockholders of the Company are parties to the Amended and Restated
Stockholders’ Agreement dated as of April 16, 2004 (the “Stockholders’ Agreement”) setting forth certain rights with respect to the registration of their shares of common stock, $0.001 par value per share (the “Common
Stock”), of the Company under the Securities Act of 1933, as amended (the “Securities Act”); 
 WHEREAS, over two years have
passed since the completion of the Company’s initial public offering of shares of Common Stock in February 2005, making certain of the agreements in the Stockholders’ Agreement unnecessary, burdensome or inappropriate for stockholders of a
public company; and 
 WHEREAS, except for affiliates of the Company, the parties to the Stockholders’ Agreement are eligible to sell
their shares of Common Stock that are the subject of the Stockholders’ Agreement in reliance on Rule 144(k) of the Securities Act. 
 NOW, THEREFORE, the undersigned, representing the holders of at least 70% of the Registrable Securities (as defined in the Stockholders’ Agreement) then held by the Holders (as defined in the Stockholders’ Agreement) whose
registration rights have not expired pursuant to Section 2.15 of the Stockholders’ Agreement do hereby agree, pursuant to and in accordance with Section 4.3 of the Stockholders’ Agreement, as follows: 
 1. Stockholders’ Agreement. The undersigned hereby approves of the termination of or amendment to the following provisions of
the Stockholders’ Agreement: 
 (i) Section 2.2(a) of the Stockholders’ Agreement be amended in its entirety and restated to
read as follows: 
 “Request for Registration. If the Company shall determine to file a registration statement with respect to any
of its securities either for its own account or the account of a security holder or holders (other than with respect to a registration statement filed pursuant to the Company’s initial public offering; a registration statement filed pursuant to
Section 2.1, 2.3 or 2.4 hereof; a “shelf” registration statement; or a registration statement covering shares to be sold solely for the account of another holder or holders, which shares were acquired pursuant to either (A) an
acquisition of a company of which they were formerly stockholders, (B) a “private placement” under the Securities Act or (C) Rule 144A under the Securities Act) at any time and from time to time, the Company will, prior to the
filing of such registration statement: 
 (i) promptly give to each Holder written notice thereof advising them of their right
to join in such registration; and 
 (ii) use its best efforts to include in such registration, except as set forth in
Section 2.2(b) below, and in any underwriting involved therein, all the Registrable Securities specified in a written request or 








 
requests, made by any Holder within twenty (20) days after the written notice from the Company described in clause (i) above is effective (which
request shall state the intended method of disposition of such Registrable Securities) to the extent necessary to permit their sale or other disposition in accordance with the intended method of distribution specified in the request of such Holder.
Such written request may specify all or a part of a Holder’s Registrable Securities. Notwithstanding the foregoing: (i) the Company shall have the right to postpone or withdraw any registration effected pursuant to this Section 2.2
without obligation to any Holder and (ii) the rights of this Section 2.2 shall not apply with respect to registration statements filed in connection with the Company’s initial public offering.” 
 (ii) Section 2.11(a) of the Stockholders’ Agreement be and hereby is terminated. 
 (iii) Section 2.15 of the Stockholders’ Agreement be amended in its entirety and restated to read as follows: 
 “All of the Company’s obligations to register Registrable Securities pursuant to this Agreement shall terminate with respect to a particular
Holder on the earlier to occur of (A) December 15, 2009 or (B) the date all shares of Registrable Securities held by such Holder may be sold pursuant to Rule 144(k).” 
 2. Waiver of Notice. The undersigned hereby waives any notice to which the undersigned may be entitled, in the undersigned’s
capacity as a stockholder or otherwise, of any agreement contemplated by this Stockholder Waiver, Amendment and Termination Agreement. 
 3. Effectiveness. The undersigned hereby agrees that this Stockholder Waiver, Amendment and Termination Agreement shall be effective for all purposes upon receipt by the Company or its counsel of signed signature pages
of this Stockholder Waiver, Amendment and Termination Agreement (or a facsimile thereof) representing the requisite stockholder consents referred to above, and that the Company is authorized to attach such signed signature pages to the pages
comprising the balance of this Stockholder Waiver, Amendment and Termination Agreement. 
 The undersigned further agrees that the agreements
herein are severable, so that in the event any transaction contemplated by one waiver, amendment or termination does not occur, the other waivers, amendments and terminations shall remain effective. 
 This Stockholder Waiver, Amendment and Termination Agreement may be executed in one or more counterparts. 
  

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 IN WITNESS WHEREOF, the undersigned has executed this Stockholder Waiver, Amendment and Termination
Agreement as of the date set forth below. 
  

									
		 		 	COMPANY:
			
		 		 	ICAGEN, INC.
				
	Dated: July 10, 2007	 		 	By:	 	/s/ P. Kay Wagoner
		 		 		 	Name:	 	P. Kay Wagoner, Ph.D.
		 		 		 	Title:	 	President and Chief Executive Officer
			
		 		 	STOCKHOLDERS:
				
	Dated: May 29, 2007	 		 	By:	 	/s/ Jean Deleage
		 		 		 	Name:	 	Jean Deleage
				
	Dated: May 24, 2007	 		 	By:	 	/s/ Juerg Geigy
		 		 		 	Name:	 	Juerg Geigy
				
	Dated: June 5, 2007	 		 	By:	 	/s/ Sheikh Isam K. Kabbani
		 		 		 	Name:	 	Sheikh Isam K. Kabbani
				
	Dated: July 10, 2007	 		 	By:	 	/s/ André L. Lamotte
		 		 		 	Name:	 	André L. Lamotte
			
		 		 	AL-MIDANI INVESTMENT COMPANY, LTD.
				
	Dated: June 4, 2007	 		 	By:	 	/s/ M. N. ALMIDANI
		 		 		 	Name:	 	M. N. ALMIDANI
		 		 		 	Title:	 	DIRECTOR
			
		 		 	ALTA BIOPHARMA PARTNERS, L.P.
				
	Dated: May 31, 2007	 		 	By:	 	Alta BioPharma Management, LLC
				
		 		 	By:	 	/s/ Alix Marduel
		 		 		 	Name:	 	Alix Marduel
		 		 		 	Title:	 	Managing Director

  

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		 		 	ALTA EMBARCADERO BIOPHARMA PARTNERS, LLC
				
	Dated: May 31, 2007	 		 	By:	 	/s/ Hilary Strain
		 		 		 	Name:	 	Hilary Strain
		 		 		 	Title:	 	Under Power of Attorney
			
		 		 	ELI LILLY AND COMPANY
				
	Dated: May 25, 2007	 		 	By:	 	/s/ James B. Lootens
		 		 		 	Name:	 	James B. Lootens
		 		 		 	Title:	 	Secretary
			
		 		 	FINOVE, LTD.
				
	Dated: June 8, 2007	 		 	By:	 	/s/ CHRISTOPHER LE BOUTILLIER
		 		 		 	Name:	 	CHRISTOPHER LE BOUTILLIER
		 		 		 	Title:	 	DIRECTOR
			
		 		 	GUTRAFIN LTD.
				
	Dated: May 25, 2007	 		 	By:	 	/s/ Francis C. Lang
		 		 		 	Name:	 	Francis C. Lang
		 		 		 	Title:	 	Senior Investment Representative
			
		 		 	HØEGH INVEST AS
				
	Dated: May 22, 2007	 		 	By:	 	/s/ Carl Preben Høegh
		 		 		 	Name:	 	Carl Preben Høegh
		 		 		 	Title:	 	Senior Partner
			
		 		 	FRED D. HUTCHISON AND NANCY HUTCHISON, TEN COM
				
	Dated: July 5, 2007	 		 	By:	 	/s/ Fred D. Hutchison
		 		 		 	Name:	 	Fred D. Hutchison, individually and as Attorney in Fact for Nancy L. Hutchinson

  

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		 		 	ICAGEN CHASE PARTNERS (ALTA BIO), LLC
				
	Dated: May 31, 2007	 		 	By:	 	Alta/Chase BioPharma Management, LLC
		 		 		 		 	
				
		 		 	By:	 	/s/ Alix Marduel
		 		 		 	Name:	 	Alix Marduel
		 		 		 	Title:	 	Member
			
		 		 	PHARMABIO DEVELOPMENT INC. d/b/a NOVAQUEST
				
	Dated: May 22, 2007	 		 	By:	 	/s/ Kerry E. Zook
		 		 		 	Name:	 	Kerry E. Zook
		 		 		 	Title:	 	V.P., General Counsel
			
		 		 	SELECTRA INVESTMENT & MANAGEMENT II, INC.
				
	Dated: May 25, 2007	 		 	By:	 	/s/ F. C. Lang
		 		 		 	Name:	 	F. C. Lang
		 		 		 	Title:	 	Chairman & CEO
			
		 		 	TRIANGLE SECURITIES AS C/F FRED D. HUTCHISON—IRA
				
	Dated: July 5, 2007	 		 	By:	 	/s/ Fred D. Hutchison
		 		 		 	Name:	 	Fred D. Hutchison, Beneficiary
			
		 		 	VENROCK ASSOCIATES
				
	Dated: May 23, 2007	 		 	By:	 	/s/ Anthony B. Evnin
		 		 		 	Name:	 	Anthony B. Evnin
		 		 		 	Title:	 	General Partner
			
		 		 	VENROCK ASSOCIATES II, L.P.
				
	Dated: May 23, 2007	 		 	By:	 	/s/ Anthony B. Evnin
		 		 		 	Name:	 	Anthony B. Evnin
		 		 		 	Title:	 	General Partner

  

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		 		 	XANTHUS LIMITED
				
	Dated: June 1, 2007	 		 	By:	 	/s/ R.M. Falla /s/ G.R. Le Page
		 		 		 	Name:	 	R.M. Falla and G.R. Le Page
		 		 		 	Title:	 	Directors
			
		 		 	ZIAD ZEIN EL ABDIN CORPORATION
				
	Dated: June 20, 2007	 		 	By:	 	/s/ Hounada Mukhtar Mohd Diab
		 		 		 	Name:	 	Hounada Mukhtar Mohd Diab
		 		 		 	Title:	 	Wife of Ziad Zein El Abdin

  

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