Common use of Agreement to Sell and Purchase the Units; Placement Agent Clause in Contracts

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below), the Sellers will sell to the Investor, and the Investor will purchase from the Sellers, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated ___, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller nor any other person acting on such Seller’s behalf has provided the Investors or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller understands and confirms that the Investors will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Canaccord Genuity Inc. (the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated ___December 9, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller the Company confirms that neither such Seller it nor any other person acting on such Seller’s its behalf has provided the Investors Investor or their any Other Investor or its respective agents or counsel with any information that it believes constitutes or could reasonably be expected to might constitute material, non-public information. Each Seller understands and confirms that information which is not otherwise disclosed in or incorporated by reference into the Investors will rely on the foregoing representations in effecting transactions in securities of the CompanyProspectus Supplement.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), . the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors each investor (collectively, the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have agreed Company intends to pay the Placement Agent a fee (the “Placement Fee”) and other consideration certain expenses in respect of the sale of Units to the InvestorUnits, as further described in the Disclosure Package. 2.4 The Company has entered into a Placement Agency Agreement, dated ___, 2010 the date hereof (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as has been or will be disclosed in the Prospectus and/or in any Current Report on Form 8-public informationK furnished or to be furnished by the Company to the Commission in accordance with Section 13. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price Purchase Price therefor set forth on the Signature Page. 2.2 The Sellers propose to Company may enter into substantially agreements similar to this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of the Units to them. (The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements”). The Company may accept or reject any one or more Agreements in its sole discretion.” 2.3 Investor acknowledges that the Sellers have agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___October 25, 2010 2007 (the “Placement Agency Agreement”), with the Placement Agent and Emory University Xxxxxxxx Curhan & Ford Co. (the “Selling StockholderPlacement Agent”), which Placement Agency Agreement ) that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. Investor acknowledges that the Company has agreed to pay the Placement Agent a fee (the “Placement Fee”) in respect of the sale of Units to the Investor. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller further confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public nonpublic information. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company. 2.4 The Company covenants and agrees to use its best efforts to keep the Registration Statement effective for as long as is needed to deliver freely tradable Warrant Shares.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Lazard Capital Markets LLC (the “Placement Agent Agent” or “LCM”) a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the InvestorInvestor and that a portion of the Placement Fee will be paid to CIBC World Markets Corp. and Nxxxxxx & Co., who have served as co-financial advisors to the Company during the Offering. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___November 2, 2010 2007 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and the Company’s Form 8-public informationK filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Xxxx Capital Partners, LLC (the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration certain expenses in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated ___the date hereof, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents hereby incorporates such representations, warranties, covenants and warrants that a true agreements herein, as if made on (a) the date hereof and correct copy of (b) the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller Closing Date. The Company confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and/or in the Company’s Form 8-public informationK to be filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated October ___, 2010 2012 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement hereto as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller the Company confirms that neither such Seller it nor any other person acting on such Seller’s its behalf has provided the Investors Investor or their any Other Investor or its respective agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below), the Sellers will sell to the Investor, and the Investor will purchase from the Sellers, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated ___, 2010 (the “Placement Agency Agreement”), with the Placement Agent Agent, Emory University, Xxxxxx X. Xxxxxxxxxx and Emory University Xxxxxxx X. Xxxxxxxx (collectively, the “Selling StockholderStockholders”), which Placement Agency Agreement contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller nor any other person acting on such Seller’s behalf has provided the Investors or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller understands and confirms that the Investors will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. At any Additional Closing (as defined in Section 3.1), the Company will sell to the Investor, and the Investor will purchase from the Company, upon the terms and conditions set forth herein, the number of Additional Shares set forth in the Additional Shares Exercise Notice for the aggregate purchase price of such shares. 2.2 The Sellers propose to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Lazard Capital Markets LLC (“LCM” or the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor, as well as upon the sale of any Additional Shares. 2.4 2.3 The Company has entered into a Placement Agency Agent Agreement, dated ___January 19, 2010 2012 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors or their agents or counsel Investor with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and the Company’s Form 8-public informationK filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Lazard Capital Markets LLC (the “Placement Agent Agent” or “LCM”) a fee (the “Placement Fee”) and other consideration certain expenses in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___the date hereof, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and/or in the Company’s Form 8-public informationK to be filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. Notwithstanding the foregoing, the Investor acknowledges and agrees that at any time prior to the Company’s filing of the press release pursuant to Section 13 below, Xxxx Capital Partners, LLC (“Xxxx” or the “Placement Agent”) may, in its discretion, reduce the allocation of Units granted to, and corresponding aggregate purchase price to be paid by, the Investor without the prior written consent of the Investor (a “Cutback”). Upon the occurrence of any Cutback, the Placement Agent shall promptly notify the Investor and may require the Investor to execute a replacement signature page to this Agreement reflecting the new reduced number of Units to be purchased by the Investor after such Cutback (the “Remaining Units”). For the avoidance of doubt, without the requirement of any amendment, waiver or written consent hereunder by any party hereto, upon any Cutback, the Company shall solely have an obligation to issue and sell to the Investor, and the Investor shall solely have an obligation to purchase the Remaining Units. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (or, alternatively, sell Securities pursuant to the Prospectus without any Subscription Agreement) (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay the Placement Agent a fee (and to reimburse the “Placement Fee”) and other consideration Agent for certain expenses in respect of the sale of Units the Securities to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___, 2010 as of the date hereof (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller nor any other person acting on such Seller’s behalf has provided the Investors or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller understands and confirms that the Investors will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price Purchase Price therefor set forth on the Signature Page. 2.2 The Sellers propose to Company may enter into substantially agreements similar to this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of the Units to them. (The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements”). The Company may accept or reject any one or more Agreements in its sole discretion.” 2.3 Investor acknowledges that the Sellers have agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___October 9, 2010 2008 (the “Placement Agency Agreement”), with the Placement Agent Xxxxxxxx Curhan & Ford Co. and Emory University Xxxxxxx Brothers, L.P. (the “Selling StockholderPlacement Agents”), which Placement Agency Agreement ) that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. Investor acknowledges that the Company has agreed to pay the Placement Agents a fee (the “Placement Fee”) in respect of the sale of Units to the Investor. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller further confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public nonpublic information. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company. 2.4 The Company covenants and agrees to use its best efforts to keep the Registration Statement effective for as long as is needed to deliver freely tradable Warrant Shares.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Lazard Capital Markets LLC (“LCM” or the “Placement Agent Agent”) a fee of six and one-half percent (6.5%) (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___, 2010 the date hereof (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller nor any other person acting on such Seller’s behalf has provided the Investors or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller understands and confirms that the Investors Investor will rely on the foregoing such representations and warranties and covenants set forth in the Placement Agent Agreement and herein in effecting transactions in securities of the Company. All of the disclosure furnished by or on behalf of the Company to the Investor regarding the Company, its business and the transactions contemplated hereby, including the Disclosure Package and the Offering Information, is true and correct in all material respects and does not contain any untrue statement of a material fact or omit to state any material fact necessary in order to make the statements made therein, in light of the circumstances under which they were made, not misleading. 2.5 The Company covenants and agrees to use its best efforts to keep the Registration Statement effective until the earlier of (x) such time as all of the Shares and Warrant Shares issued or issuable can be sold by the Investor or its affiliates immediately without compliance with the registration requirements of the Act pursuant to Rule 144 under the Act and (y) the date all of the Shares and Warrant Shares issued or issuable shall have been sold by the Investor and its affiliates.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay the Placement Agent a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated __________, 2010 2011 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”)Agent, which Placement Agency Agreement contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller the Company confirms that neither such Seller it nor any other person acting on such Seller’s its behalf has provided the Investors or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, non-public information. Each Seller information The Company understands and confirms that the Investors will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Canaccord Genuity Inc. (the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agreement, dated ___July 1, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller the Company confirms that neither such Seller it nor any other person acting on such Seller’s its behalf has provided the Investors Investor or their any Other Investor or its respective agents or counsel with any information that it believes constitutes or could reasonably be expected to might constitute material, non-public information. Each Seller understands and confirms that information which is not otherwise disclosed in or incorporated by reference into the Investors will rely on the foregoing representations in effecting transactions in securities of the CompanyProspectus Supplement.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. 2.2 The Sellers propose Company proposes to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect expects to complete sales of Units to them. The Investor and the Other Investors, if any, Investors are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Xxxxxxx Xxxxx & Company, L.L.C. (the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration certain expenses in respect of the sale of Units to the Investor. 2.4 The Company has entered into a Placement Agency Agent Agreement, dated ___the date hereof, 2010 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors Investor or their agents or counsel with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and/or in the Company’s Form 8-public informationK to be filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.

Agreement to Sell and Purchase the Units; Placement Agent. 2.1 At the Closing (as defined in Section 3.1 below3.1), the Sellers Company will sell to the Investor, and the Investor will purchase from the SellersCompany, upon the terms and conditions set forth herein, the number of Units set forth on the last page of the Agreement to which these Terms and Conditions for Purchase of Units are attached as Annex I (the “Signature Page”) for the aggregate purchase price therefor set forth on the Signature Page. At any Additional Closing (as defined in Section 3.1), the Company will sell to the Investor, and the Investor will purchase from the Company, upon the terms and conditions set forth herein, the number of Additional Shares set forth in the Additional Shares Exercise Notice for the aggregate purchase price of such shares. 2.2 The Sellers propose to enter into substantially this same form of Subscription Agreement with certain other investors (the “Other Investors”) and expect to complete sales of Units to them. The Investor and the Other Investors, if any, are hereinafter sometimes collectively referred to as the “Investors,” and this Agreement and the Subscription Agreements executed by the Other Investors are hereinafter sometimes collectively referred to as the “Agreements.” 2.3 Investor acknowledges that the Sellers have Company has agreed to pay Lazard Capital Markets LLC (“LCM” or the “Placement Agent Agent”) a fee (the “Placement Fee”) and other consideration in respect of the sale of Units to the Investor, as well as upon the exercise of the Warrants and the sale of any Additional Shares. 2.4 2.3 The Company has entered into a Placement Agency Agent Agreement, dated ___January 10, 2010 2011 (the “Placement Agency Agreement”), with the Placement Agent and Emory University (the “Selling Stockholder”), which Placement Agency Agreement that contains certain representations, warranties, covenants and agreements of the Company that may be relied upon by the Investor, which shall be a third party beneficiary thereof. The Company represents and warrants that a true and correct copy of the Placement Agency Agreement is attached to this Agreement as Exhibit B. Except with respect to the material terms and conditions of the transactions contemplated by this Agreement, the Placement Agency Agreement and any other documents or agreements contemplated hereby or thereby, each Seller confirms that neither such Seller it nor any other person Person acting on such Seller’s its behalf has provided the Investors or their agents or counsel Investor with any information that constitutes or could reasonably be expected to constitute material, nonnonpublic information, except as will be disclosed in the Prospectus and the Company’s Form 8-public informationK filed with the Commission in connection with the Offering. Each Seller The Company understands and confirms that the Investors Investor will rely on the foregoing representations in effecting transactions in securities of the Company.