EXECUTION VERSION SECURITIES PURCHASE AGREEMENT This Securities Purchase Agreement (this “Agreement”) is dated as of November 2, 2019 by and among Pieris Pharmaceuticals, Inc., a Nevada corporation (the “Company”), and each purchaser identified on the...

EXECUTION VERSION SECURITIES PURCHASE AGREEMENT This Securities Purchase Agreement (this “Agreement”) is dated as of November 2, 2019 by and among Pieris Pharmaceuticals, Inc., a Nevada corporation (the “Company”), and each purchaser identified on the signature pages hereto (each, including its successors and assigns, a “Purchaser” and collectively, the “Purchasers”). RECITALS A. The Company and each Purchaser is executing and delivering this Agreement in reliance upon the exemption from securities registration afforded by Section 4(a)(2) of the Securities Act of 1933, as amended (the “Securities Act”), and Rule 506 of Regulation D (“Regulation D”) as promulgated by the United States Securities and Exchange Commission (the “Commission”) under the Securities Act. B. Each Purchaser, severally and not jointly, wishes to purchase, and the Company wishes to sell, upon the terms and conditions stated in this Agreement: (i) that aggregate number of shares of common stock, par value $0.001 per share (the “Common Stock”), of the Company, set forth below such Purchaser’s name on the signature page of this Agreement (which aggregate amount for all Purchasers together shall be 5,492,960 shares of Common Stock (the “Common Shares”)), (ii) that aggregate number of shares of Series C Convertible Preferred Stock, par value $0.001 per share (the “Preferred Stock”), of the Company, if any, set forth below such Purchaser’s name on the signature page of this Agreement (which aggregate amount for all Purchasers together shall be 3,522 shares of Preferred Stock (the “Preferred Shares” and, together with the Common Shares shall be collectively referred to herein as the “Shares”)) (the shares of Common Stock issuable upon conversion of the Preferred Stock collectively are referred to herein as the “Underlying Shares”) and (iii) warrants, in substantially the form attached hereto as Exhibit A (the “Warrants”), to acquire up to that number of additional shares of Common Stock equal to 100% of the number of Shares purchased by such Purchaser (for such purpose, counting the Preferred Shares with reference to the number of Underlying Shares), rounded up to the nearest whole share (the shares of Common Stock issuable upon exercise of or otherwise pursuant to the Warrants collectively are referred to herein as the “Warrant Shares”). C. The Shares, the Underlying Shares, the Warrants and the Warrant Shares collectively are referred to herein as the “Securities”. D. The Company has engaged Xxxxxxx Xxxxx & Company to act as lead placement agent (the “Placement Agent”) for the offering of the Shares and Warrants on a “best efforts” basis. E. Contemporaneously with the execution and delivery of this Agreement, the parties hereto are executing and delivering a Registration Rights Agreement, substantially in the form attached hereto as Exhibit B (the “Registration Rights Agreement”), pursuant to which, among other things, the Company will agree to provide certain registration rights with respect to the Shares and the Warrant Shares under the Securities Act and the rules and regulations promulgated thereunder and applicable state securities laws.

NOW, THEREFORE, IN CONSIDERATION of the mutual covenants contained in this Agreement, and for other good and valuable consideration, the receipt and adequacy of which are hereby acknowledged, the Company and each Purchaser hereby agree as follows: ARTICLE I DEFINITIONS Section 1.1 Definitions. In addition to the terms defined elsewhere in this Agreement, for all purposes of this Agreement, the following terms shall have the meanings indicated in this Section 1.1: “Action” means any action, suit, inquiry, notice of violation, proceeding (including any partial proceeding such as a deposition) or investigation pending or, to the Company’s Knowledge, threatened against the Company or any of their respective properties or any officer, director or employee of the Company acting in his or her capacity as an officer, director or employee before or by any federal, state, county, local or foreign court, arbitrator, governmental or administrative agency, regulatory authority, stock market, stock exchange or trading facility. “Accredited Investor Questionnaire” means the Accredited Investor Questionnaire set forth as Exhibit F hereto. “Affiliate” means, with respect to any Person, any other Person that, directly or indirectly through one or more intermediaries, Controls, is controlled by or is under common control with such Person, as such terms are used in and construed under Rule 405 under the Securities Act. With respect to a Purchaser, any investment fund or managed account that is managed on a discretionary basis by the same investment manager as such Purchaser will be deemed to be an Affiliate of such Purchaser. “Board of Directors” means the board of directors of the Company. “Business Day” means any day except Saturday, Sunday, any day which is a federal legal holiday in the United States or any day on which banking institutions in the State of New York are authorized or required by law or other governmental action to close. “Certificate of Designation” means the Certificate of Designation to be filed prior to the Closing by the Company with the Nevada Secretary of State, in the form of Exhibit E attached hereto. “Closing” means the closing of the purchase and sale of the Shares and the Warrants on the Closing Date pursuant to Section 2.1. “Closing Bid Price” means, for any security as of any date: (a) the last reported closing bid price per share for such security on the Principal Trading Market, as reported by Bloomberg Financial Markets, or, (b) if the Principal Trading Market begins to operate on an extended hours basis and does not designate the closing bid price then the last bid price of such security prior to 4:00 p.m., New York City time, as reported by Bloomberg Financial Markets, or (c) if the foregoing do not apply, the last closing price of such security in the over-the-counter market on the electronic bulletin board for such security as reported by Bloomberg Financial Markets, or, 2

(d) if no closing bid price is reported for such security by Bloomberg Financial Markets, the average of the bid prices of any market makers for such security as reported in the “pink sheets” by Pink Sheets LLC. If the Closing Bid Price cannot be calculated for a security on a particular date on any of the foregoing bases, the Closing Bid Price of such security on such date shall be the fair market value as mutually determined by the Company and the holder of such security. If the Company and such holder are unable to agree upon the fair market value of such security, then the Board of Directors shall use its good faith judgment to determine the fair market value. The Board of Directors’ determination shall be binding on all parties absent demonstrable error. All such determinations shall be appropriately adjusted for any stock dividend, stock split, stock combination or other similar transaction during the applicable calculation period. “Closing Date” means the Trading Day when all of the Transaction Documents have been executed and delivered by the applicable parties thereto, and all of the conditions set forth in Sections 2.1, 2.2, 5.1 and 5.2 hereof are satisfied or waived, as the case may be, or such other date as the parties may agree. “Common Stock” has the meaning set forth in the Recitals, and also includes any other class of securities into which the Common Stock may hereafter be reclassified or changed. “Common Stock Equivalents” means any securities of the Company which would entitle the holder thereof to acquire at any time Common Stock, including, without limitation, any debt, preferred stock, rights, options, warrants or other instrument that is at any time convertible into or exchangeable for, or otherwise entitles the holder thereof to receive, Common Stock or other securities that entitle the holder to receive, directly or indirectly, Common Stock. “Company Counsel” means Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., with offices located at Xxx Xxxxxxxxx Xxxxxx, Xxxxxx, Xxxxxxxxxxxxx 00000. “Company Covered Person” means, with respect to the Company as an “issuer” for purposes of Rule 506 promulgated under the Securities Act, any Person listed in the first paragraph of Rule 506(d)(1). “Company’s Knowledge” means with respect to any statement made to the Company’s Knowledge, that the statement is based upon the actual knowledge of the officers of the Company having responsibility for the matter or matters that are the subject of the statement, after reasonable inquiry. “Control” (including the terms “controlling”, “controlled by” or “under common control with”) means the possession, direct or indirect, of the power to direct or cause the direction of the management and policies of a Person, whether through the ownership of voting securities, by contract or otherwise. “Effective Date” means the date on which the initial Registration Statement required by Section 2(a) of the Registration Rights Agreement is first declared effective by the Commission. “Exchange Act” means the Securities Exchange Act of 1934, as amended, or any successor statute, and the rules and regulations promulgated thereunder. 3

“GAAP” means U.S. generally accepted accounting principles, as applied by the Company. “Lien” means any lien, charge, claim, encumbrance, security interest, right of first refusal, preemptive right or other restrictions of any kind. “Material Adverse Effect” means a material adverse effect on the results of operations, assets, prospects, business or financial condition of the Company, except that any of the following, either alone or in combination, shall not be deemed a Material Adverse Effect: (i) effects caused by changes or circumstances affecting general market conditions in the U.S. or applicable foreign economy or which are generally applicable to the industry in which the Company operates, provided that such effects are not borne disproportionately by the Company, or (ii) effects caused by earthquakes, hostilities, acts of war, sabotage or terrorism or military actions or any escalation or material worsening of any such hostilities, acts of war, sabotage or terrorism or military actions existing as of the date hereof. “Material Contract” means any contract of the Company that has been filed or was required to have been filed as an exhibit to the SEC Reports pursuant to Item 601(b)(4) or Item 601(b)(10) of Regulation S-K. “New York Courts” means the state and federal courts sitting in the City of New York, Borough of Manhattan. “Nevada Counsel” means Xxxxxxxxxx Xxxxx Xxxxxx Xxxxxxx, LLP, with offices located at 000 Xxxxx Xxxx Xxxxxxx, Xxxxx 0000, Xxx Xxxxx, Xxxxxx 00000. “Outside Date” means the tenth (10th) Business Day following the date of this Agreement. “Person” means an individual, corporation, partnership, limited liability company, trust, business trust, association, joint stock company, joint venture, sole proprietorship, unincorporated organization, governmental authority or any other form of entity not specifically listed herein. “Principal Trading Market” means the Trading Market on which the Common Stock is primarily listed on and quoted for trading, which, as of the date of this Agreement and the Closing Date, shall be the Nasdaq Capital Market. “Pro Rata Portion” means, with respect to any Purchaser, the ratio of (i) such Purchaser’s Subscription Amount and (ii) the aggregate sum of the Subscription Amounts for all of the Purchasers. “Proceeding” means an Action, claim, suit, investigation or proceeding (including, without limitation, an investigation or partial proceeding, such as a deposition), whether commenced or threatened. “Purchase Price” means $3.55 per unit, with $3.425 of each unit attributable to the share of Common Stock or Preferred Stock (for such purpose, counting the Preferred Shares with 4

reference to the number of Underlying Shares), as applicable, included therein and $0.125 of each unit attributable to the Warrants included therein to purchase each Warrant Share. “Registration Statement” means a registration statement meeting the requirements set forth in the Registration Rights Agreement and covering the resale by the Purchasers of the Registrable Securities (as defined in the Registration Rights Agreement). “Rule 144” means Rule 144 promulgated by the Commission pursuant to the Securities Act, as such Rule may be amended from time to time, or any similar rule or regulation hereafter adopted by the Commission having substantially the same effect as such Rule. “Short Sales” include, without limitation, (i) all “short sales” as defined in Rule 200 promulgated under Regulation SHO under the Exchange Act, whether or not against the box, and all types of direct and indirect stock pledges, forward sale contracts, options, puts, calls, short sales, swaps, “put equivalent positions” (as defined in Rule 16a-1(h) under the Exchange Act) and similar arrangements (including on a total return basis), and (ii) sales and other transactions through non-U.S. broker dealers or foreign regulated brokers (but shall not be deemed to include the location and/or reservation of borrowable shares of Common Stock). “Subscription Amount” means, with respect to each Purchaser, the aggregate amount to be paid for the Shares and the related Warrants purchased hereunder as indicated on such Purchaser’s signature page to this Agreement next to the heading “Aggregate Purchase Price (Subscription Amount)” in United States dollars and in immediately available funds. “Subsidiary” means any subsidiary of the Company as set forth on Schedule 3.1(a), and shall, where applicable, include any subsidiary of the Company formed or acquired after the date hereof. “Trading Affiliate” means an Affiliate of a Purchaser who (x) had knowledge of the transactions contemplated hereby, (y) has or shares discretion relating to such Purchaser’s investments or trading or information concerning such Purchaser’s investments, including in respect of the Securities, and (z) is subject to such Purchaser’s review or input concerning such Affiliate’s investments or trading. “Trading Day” means (i) a day on which the Common Stock is listed or quoted and traded on its Principal Trading Market (other than the OTCMarkets), or (ii) if the Common Stock is not listed on a Trading Market (other than the OTCMarkets), a day on which the Common Stock is traded in the over-the-counter market, as reported by the OTCMarkets, or (iii) if the Common Stock is not quoted on any Trading Market, a day on which the Common Stock is quoted in the over-the-counter market as reported in the “pink sheets” by Pink Sheets LLC (or any similar organization or agency succeeding to its functions of reporting prices); provided, that in the event that the Common Stock is not listed or quoted as set forth in (i), (ii) and (iii) hereof, then Trading Day shall mean a Business Day. “Trading Market” means whichever of the New York Stock Exchange, the NYSE Mkt, the Nasdaq Global Select Market, the Nasdaq Global Market, the Nasdaq Capital Market or the OTCMarkets on which the Common Stock is listed or quoted for trading on the date in question. 5

“Transaction Documents” means this Agreement, the schedules and exhibits attached hereto, the Warrants, the Registration Rights Agreement, the Irrevocable Transfer Agent Instructions and any other documents or agreements explicitly contemplated hereunder. “Transfer Agent” means Computershare Trust Company, N.A., the current transfer agent of the Company, with a mailing address of 000 Xxxxxx Xxxxxx #0000, Xxxxxx, XX 00000 0, and a telephone number of (000) 000-0000, or any successor transfer agent for the Company. ARTICLE II PURCHASE AND SALE Section 2.1 Closing. (a) Amount. Subject to the terms and conditions set forth in this Agreement, at the Closing, the Company shall issue and sell to each Purchaser, and each Purchaser shall, severally and not jointly, purchase from the Company, such number of units equal to the quotient resulting from dividing (i) the Subscription Amount for such Purchaser as indicated below such Purchaser’s name on its signature page to this Agreement by (ii) the Purchase Price, rounded down to the nearest whole Share. A “unit” shall consist of (x) one share of Common Stock or 0.001 shares of Preferred Stock, as applicable, and (y) a Warrant to purchase one Warrant Share at an exercise price of $7.10 per share, subject to adjustment as provided in such Warrants. (b) Closing. The Closing of the purchase and sale of the Shares and Warrants shall take place at the offices of Xxxxxxx Procter LLP, The New York Times Building, 000 Xxxxx Xxxxxx, Xxx Xxxx, Xxx Xxxx 00000 on the Closing Date or at such other location(s) or remotely by facsimile transmission or other electronic means as the parties may mutually agree. (c) Form of Payment. Except as may otherwise be agreed to among the Company and one or more of the Purchasers, on or prior to the Business Day immediately prior to the Closing Date, each Purchaser shall wire its Subscription Amount, in United States dollars and in immediately available funds, to a bank account designated by the Company. (d) On the Closing Date, upon receipt of the aggregate Purchase Price: (i) the Company shall irrevocably instruct the Transfer Agent to deliver to each Purchaser (within three Trading Days after the Closing) one or more stock certificates, or evidence of book entry, free and clear of all restrictive and other legends (except as expressly provided in Section 4.1(b) hereof), evidencing the number of Shares such Purchaser is purchasing as is set forth on such Purchaser’s signature page to this Agreement next to the heading “Number and Type of Shares to be Acquired,” and (ii) the Company shall on the Business Day following the Closing Date send for overnight delivery to each Purchaser one or more Warrants, free and clear of all restrictive and other legends (except as expressly provided in Section 4.1(b) hereof), evidencing the number of Warrant Shares such Purchaser is entitled to purchase as is set forth on such Purchaser’s signature page to this Agreement next to the heading “Warrant Shares Subject to Warrant.” Section 2.2 Closing Deliveries. 6

(a) On or prior to the Closing, the Company shall issue, deliver or cause to be delivered to each Purchaser the following (the “Company Deliverables”): (i) facsimile or .pdf copies of one or more stock certificates, free and clear of all restrictive and other legends (except as provided in Section 4.1(b) hereof), evidencing the Shares subscribed for by such Purchaser hereunder, registered in the name of such Purchaser as set forth on the signature pages hereto (the “Stock Certificates”), with the original Stock Certificates delivered by the Transfer Agent within three Trading Days of Closing; (ii) facsimile or .pdf copies of one or more Warrants, executed by the Company and registered in the name of such Purchaser as set forth on the signature pages hereto, pursuant to which such Purchaser shall have the right to acquire such number of Warrant Shares equal to 100% of the number of Shares (for such purpose, counting the Preferred Shares with reference to the number of Underlying Shares) issuable to such Purchaser pursuant to Section 2.2(a)(i), rounded up to the nearest whole share (provided, however, that in the event any Purchasers are Affiliates of each other, all Shares purchased by such Purchasers shall be aggregated together for the purpose of determining the aggregate number of Warrant Shares subject to all Warrants purchased by such Purchasers), on the terms set forth therein, with the original Warrants to be sent on the Business Day following the Closing Date for overnight delivery to the Purchasers; (iii) a legal opinion of (A) Company Counsel, dated as of the Closing Date and in substantially the form attached hereto as Exhibit C-1, executed by such counsel and addressed to the Purchasers and the Placement Agent, and (B) Nevada Counsel, dated as of the Closing Date and in substantially the form attached hereto as Exhibit C-2, executed by such counsel and addressed to the Purchasers and the Placement Agent; (iv) the Registration Rights Agreement, duly executed by the Company; (v) duly executed Irrevocable Transfer Agent Instructions acknowledged in writing by the Transfer Agent instructing the Transfer Agent to deliver, on an expedited basis, a certificate evidencing a number of Shares equal to such Purchaser’s Subscription Amount divided by the Purchase Price, registered in the name of such Purchaser; and (vi) the Compliance Certificate referred to in Section 5.1(h). (b) On or prior to the Closing, each Purchaser shall deliver or cause to be delivered to the Company (or the Placement Agent in the case of clause (ii) below) the following, with respect to such Purchaser (the “Purchaser Deliverables”): (i) subject to the completion of Section 2.2(a)(i) and (ii), its Subscription Amount, in United States dollars and in immediately available funds, in the amount set forth as the “Purchase Price” indicated below such Purchaser’s name on the applicable signature page hereto under the heading “Aggregate Purchase Price (Subscription Amount)” by wire transfer to a bank account designated by the Company; 7

(ii) the Registration Rights Agreement, duly executed by such Purchaser; (iii) a fully completed and duly executed Accredited Investor Questionnaire, satisfactory to the Company, in the form attached hereto as Exhibit F. ARTICLE III REPRESENTATIONS AND WARRANTIES Section 3.1 Representations and Warranties of the Company. Except as (i) set forth in the schedules delivered herewith (the “Disclosure Schedules”), which Disclosure Schedules shall be deemed a part hereof and shall qualify any representation made herein to the extent of the disclosure contained in the corresponding section of the Disclosure Schedules, or (ii) disclosed in the SEC Reports, the Company hereby represents and warrants as of the date hereof and the Closing Date (except for the representations and warranties that speak as of a specific date, which shall be made as of such date), to each of the Purchasers and the Placement Agent: (a) Subsidiaries. The Company has no direct or indirect Subsidiaries other than those listed in Schedule 3.1(a) hereto. Except as disclosed in Schedule 3.1(a) hereto, the Company owns, directly or indirectly, all of the capital stock or comparable equity interests of each Subsidiary free and clear of any and all Liens, and all the issued and outstanding shares of capital stock or comparable equity interest of each Subsidiary are validly issued and are fully paid, non-assessable and free of preemptive and similar rights to subscribe for or purchase securities. (b) Organization and Qualification. The Company and each of its Subsidiaries is an entity duly incorporated or otherwise organized, validly existing and in good standing under the laws of the jurisdiction of its incorporation or organization (as applicable), with the requisite corporate power and authority to own or lease and use its properties and assets and to carry on its business as currently conducted. Neither the Company nor any Subsidiary is in violation or default of any of the provisions of its articles of incorporation or bylaws or other organizational documents. The Company and each of its Subsidiaries is duly qualified to conduct business and is in good standing as a foreign corporation or other entity in each jurisdiction in which the nature of the business conducted or property owned by it makes such qualification necessary, except where the failure to be so qualified or in good standing, as the case may be, would not have or reasonably be expected to result in a Material Adverse Effect, and no Proceeding has been instituted, is pending, or, to the Company’s Knowledge, has been threatened in any such jurisdiction revoking, limiting or curtailing or seeking to revoke, limit or curtail such power and authority or qualification. (c) Authorization; Enforcement; Validity. The Company has the requisite corporate power and authority to enter into and to consummate the transactions contemplated by each of the Transaction Documents to which it is a party and otherwise to carry out its obligations hereunder and thereunder. The Company’s execution and delivery of each of the Transaction Documents to which it is a party and the consummation by it of the transactions 8

contemplated hereby and thereby (including, but not limited to, the sale and delivery of the Shares and the Warrants and the reservation for issuance and the subsequent issuance of the Warrant Shares upon exercise of the Warrants) have been duly authorized by all necessary corporate action on the part of the Company, and no further corporate action is required by the Company, its Board of Directors or its stockholders in connection therewith other than in connection with the Required Approvals. Each of the Transaction Documents to which it is a party has been (or upon delivery will have been) duly executed by the Company and is, or when delivered in accordance with the terms hereof, will constitute the legal, valid and binding obligation of the Company enforceable against the Company in accordance with its terms, except (i) as such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium, liquidation or similar laws relating to, or affecting generally the enforcement of, creditors’ rights and remedies or by other equitable principles of general application, (ii) as limited by laws relating to the availability of specific performance, injunctive relief or other equitable remedies and (iii) insofar as indemnification and contribution provisions may be limited by applicable law. (d) No Conflicts. The execution, delivery and performance by the Company of the Transaction Documents to which it is a party and the consummation by the Company of the transactions contemplated hereby or thereby (including, without limitation, the issuance of the Shares and Warrants and the reservation for issuance and issuance of the Warrant Shares) do not and will not (i) conflict with or violate any provisions of the Company’s or any Subsidiary’s articles of incorporation or bylaws or other similar organizational documents of any Subsidiary, (ii) conflict with, or constitute a default (or an event that with notice or lapse of time or both would result in a default) under, result in the creation of any Lien upon any of the properties or assets of the Company or any Subsidiary or give to others any rights of termination, amendment, acceleration or cancellation (with or without notice, lapse of time or both) of, any Material Contract, or (iii) subject to the Required Approvals, conflict with or result in a violation of any law, rule, regulation, order, judgment, injunction, decree or other restriction of any court or governmental authority to which the Company or a Subsidiary is subject (including federal and state securities laws and regulations and the rules and regulations, assuming the correctness of the representations and warranties made by the Purchasers herein, of any self-regulatory organization to which the Company or its securities are subject, including all applicable Trading Markets), or by which any property or asset of the Company is bound or affected, except in the case of clauses (ii) and (iii) such as would not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect or a material adverse effect on the legality, validity or enforceability of any Transaction Document or the Company’s ability to perform in any material respect on a timely basis its obligations under any Transaction Document. (e) Filings, Consents and Approvals. Neither the Company nor any of its Subsidiaries is required to obtain any consent, waiver, approval, authorization or order of, give any notice to, or make any filing or registration with, any court or other federal, state, local or other governmental authority, holder of outstanding securities of the Company or other Person in connection with the execution, delivery and performance by the Company of the Transaction Documents (including the issuance of the Securities), other than (i) the filing with the Commission of one or more Registration Statements in accordance with the requirements of the Registration Rights Agreement, (ii) filings required by applicable state securities laws, (iii) the 9

filing of a Notice of Sale of Securities on Form D with the Commission under Regulation D of the Securities Act, (iv) the filing of any requisite notices and/or application(s) to the Principal Trading Market for the issuance and sale of the Securities and the listing of the Shares and Warrant Shares for trading or quotation, as the case may be, thereon in the time and manner required thereby, (v) the filings required in accordance with Section 4.4 of this Agreement and (vi) those that have been made or obtained prior to the date of this Agreement (collectively, the “Required Approvals”). (f) Issuance of the Securities. The Shares have been duly authorized and, when issued and paid for in accordance with the terms of the Transaction Documents, will be duly and validly issued, fully paid and non-assessable and free and clear of all Liens, other than restrictions on transfer provided for in the Transaction Documents or imposed by applicable securities laws, and shall not be subject to preemptive or similar rights of stockholders. The Warrants have been duly authorized and, when issued and paid for in accordance with the terms of the Transaction Documents, will be duly and validly issued, free and clear of all Liens, other than restrictions on transfer provided for in the Transaction Documents or imposed by applicable securities laws, and shall not be subject to preemptive or similar rights of stockholders. The Warrant Shares issuable upon exercise of the Warrants have been duly authorized and, when issued and paid for in accordance with the terms of the Transaction Documents and the Warrants, will be duly and validly issued, fully paid and non-assessable, free and clear of all Liens, other than restrictions on transfer provided for in the Transaction Documents or imposed by applicable securities laws, and shall not be subject to preemptive or similar rights of stockholders. Assuming the accuracy of the representations and warranties of the Purchasers in this Agreement, the Securities will be issued in compliance with all applicable federal and state securities laws. As of the Closing Date, the Company shall have reserved from its duly authorized capital stock the number of shares of Common Stock issuable upon exercise of the Warrants (without taking into account any limitations on the exercise of the Warrants set forth in the Warrants). The Company shall, so long as any of the Warrants are outstanding, take all action necessary to reserve and keep available out of its authorized and unissued capital stock, solely for the purpose of effecting the exercise of the Warrants, the number of shares of Common Stock issuable upon exercise of the Warrants (without taking into account any limitations on the exercise of the Warrants set forth in the Warrants). No “bad actor” disqualifying event described in Rule 506(d)(1)(i)-(viii) of the Securities Act (a “Disqualification Event”) is applicable to the Company or, to the Company’s knowledge, any Company Covered Person, except for a Disqualification Event as to which Rule 506(d)(2)(ii–iv) or (d)(3), is applicable. (g) Capitalization. The capitalization of the Company is as described in its most recently filed SEC Report on Form 10-Q, except for issuances pursuant to this Agreement, stock option exercises, issuances pursuant to equity incentive plans, exercises of warrants or issuances pursuant to the Company’s “at the market” equity program. The Company has not issued any capital stock since the date of its most recently filed SEC Report other than to reflect stock option and warrant exercises that do not, individually or in the aggregate, have a material effect on the issued and outstanding capital stock, options and other securities of the Company. No Person has any right of first refusal, preemptive right, right of participation, or any similar right to participate in the transactions contemplated by the Transaction Documents that have not been effectively waived as of the Closing Date. Except as set forth on Schedule 3.1(g) or a result of the purchase and sale of the Shares and Warrants, there are no outstanding options, warrants, 10

scrip rights to subscribe to, calls or commitments of any character whatsoever relating to, or securities, rights or obligations convertible into or exercisable or exchangeable for, or giving any Person any right to subscribe for or acquire any shares of Common Stock, or contracts, commitments, understandings or arrangements by which the Company or any Subsidiary is or may become bound to issue additional shares of Common Stock or Common Stock Equivalents. Except as set forth on Schedule 3.1(g), the issuance and sale of the Shares and Warrants will not obligate the Company to issue shares of Common Stock or other securities to any Person (other than the Purchasers) and will not result in a right of any holder of Company securities to adjust the exercise, conversion, exchange or reset price under any of such securities. All of the outstanding shares of capital stock of the Company are validly issued, fully paid and non- assessable, have been issued in compliance in all material respects with all applicable federal and state securities laws, and none of such outstanding shares was issued in violation of any preemptive rights or similar rights to subscribe for or purchase securities which violation would have or would reasonably be expected to result in a Material Adverse Effect. There are no stockholders agreements, voting agreements or other similar agreements with respect to the Company’s capital stock to which the Company is a party or, to the Company’s Knowledge, between or among any of the Company’s stockholders. (h) SEC Reports; Disclosure Materials. The Company has filed all reports, schedules, forms, statements and other documents required to be filed by it under the Exchange Act, including pursuant to Section 13(a) or 15(d) thereof, for the 12 months preceding the date hereof (or such shorter period as the Company was required by law or regulation to file such material) (the foregoing materials, including the exhibits thereto and documents incorporated by reference therein, being collectively referred to herein as the “SEC Reports”, and the SEC Reports, together with the Disclosure Schedules, being collectively referred to as the “Disclosure Materials”) on a timely basis or has received a valid extension of such time of filing and has filed any such SEC Reports prior to the expiration of any such extension, except where the failure to file on a timely basis would not have or reasonably be expected to result in a Material Adverse Effect and would not have or reasonably be expected to result in any limitation or prohibition on the Company’s ability to register the Shares and Warrant Shares for resale on Form S-3 or any Purchaser’s ability to use Rule 144 to resell any Securities. As of their respective filing dates, or to the extent corrected by a subsequent amendment, the SEC Reports complied in all material respects with the requirements of the Securities Act and the Exchange Act and the rules and regulations of the Commission promulgated thereunder, and none of the SEC Reports, when filed, contained any untrue statement of a material fact or omitted to state a material fact required to be stated therein or necessary in order to make the statements therein, in light of the circumstances under which they were made, not misleading. Each of the Material Contracts to which the Company or any Subsidiary is a party or to which the property or assets of the Company or any of its Subsidiaries are subject has been filed (or incorporated by reference) as an exhibit to the SEC Reports. (i) Financial Statements. The consolidated financial statements of the Company included in the SEC Reports comply in all material respects with applicable accounting requirements and the rules and regulations of the Commission with respect thereto as in effect at the time of filing (or to the extent corrected by a subsequent amendment). Such consolidated financial statements have been prepared in accordance with GAAP applied on a consistent basis during the periods involved, except as may be otherwise specified in such 11

financial statements or the notes thereto and except that unaudited financial statements may not contain all footnotes required by GAAP, and fairly present in all material respects the financial position of the Company and its consolidated Subsidiaries taken as a whole as of and for the dates thereof and the results of operations and cash flows for the periods then ended, subject, in the case of unaudited statements, to normal, immaterial year-end audit adjustments. (j) Material Changes. Since the date of the latest financial statements included within the SEC Reports, except as specifically disclosed in a subsequent SEC Report filed prior to the date hereof and except as disclosed in Schedule 3.1(j), (i) there have been no events, occurrences or developments that have had or would reasonably be expected to have, either individually or in the aggregate, a Material Adverse Effect, (ii) the Company has not incurred any material liabilities (contingent or otherwise) other than (A) trade payables and accrued expenses incurred in the ordinary course of business consistent with past practice and (B) liabilities not required to be reflected in the Company’s financial statements pursuant to GAAP or required to be disclosed in filings made with the Commission, (iii) the Company has not altered materially its method of accounting or the manner in which it keeps its accounting books and records, (iv) the Company has not declared or made any dividend or distribution of cash or other property to its stockholders or purchased, redeemed or made any agreements to purchase or redeem any shares of its capital stock (other than in connection with repurchases of unvested stock issued to employees of the Company) and (v) the Company has not issued any equity securities to any officer, director or Affiliate, except Common Stock issued in the ordinary course as dividends on outstanding preferred stock or issued pursuant to existing Company stock option or stock purchase plans or executive and director compensation arrangements disclosed in the SEC Reports. Except as disclosed in Schedule 3.1(j) and except for the issuance of the Shares and Warrants contemplated by this Agreement, no event, liability or development has occurred or exists with respect to the Company or its Subsidiaries or their respective business, properties, operations or financial condition, that would be required to be disclosed by the Company under applicable securities laws at the time this representation is made that has not been publicly disclosed at least one Trading Day prior to the date that this representation is made. (k) Litigation. There is no Action which (i) adversely affects or challenges the legality, validity or enforceability of any of the Transaction Documents or the Securities or (ii) except as disclosed in Schedule 3.1(k), would, if there were an unfavorable decision, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect. During the past five years, neither the Company nor any Subsidiary, nor to the Company’s Knowledge any director or officer thereof, is or has been the subject of any Action involving a claim of violation of or liability under federal or state securities laws or a claim of breach of fiduciary duty. There has not been, and to the Company’s Knowledge there is not pending or contemplated, any investigation by the Commission involving the Company or any current or former director or officer of the Company. During the past five years, the Commission has not issued any stop order or other order suspending the effectiveness of any registration statement filed by the Company under the Exchange Act or the Securities Act. (l) Employment Matters. No material labor dispute exists or, to the Company’s Knowledge, is imminent with respect to any of the employees of the Company which would have or would reasonably be expected to result in a Material Adverse Effect. None of the Company’s or any Subsidiary’s employees is a member of a labor union that relates to 12

such employee’s relationship with the Company, and neither the Company nor any of its Subsidiaries is a party to a collective bargaining agreement. Except as disclosed in Schedule 3.1(l), no executive officer of the Company (as defined in Rule 501(f) of the Securities Act) has notified the Company or any of its Subsidiaries that such officer intends to leave the Company or any such Subsidiary or otherwise terminate such officer’s employment with the Company or any such Subsidiary. To the Company’s Knowledge, no executive officer or key employee, is, or is now expected to be, in violation of any material term of any employment contract, confidentiality, disclosure or proprietary information agreement or non-competition agreement, or any other contract or agreement or any restrictive covenant in favor of any third party, and to the Company’s Knowledge, the continued employment of each such executive officer or key employee does not subject the Company or any Subsidiary to any liability with respect to any of the foregoing matters, except, in each case, matters that, individually or in the aggregate, would not reasonably be expected to result in a Material Adverse Effect. The Company is in compliance with all U.S. federal, state, local and foreign laws and regulations relating to employment and employment practices, terms and conditions of employment and wages and hours, except where the failure to be in compliance would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect. (m) Compliance. Neither the Company nor any of its Subsidiaries (i) is in default under or in violation of (and no event has occurred that has not been waived that, with notice or lapse of time or both, would result in a default by the Company or any of its Subsidiaries under), nor has the Company or any of its Subsidiaries received written notice of a claim that it is in default under or that it is in violation of, any Material Contract (whether or not such default or violation has been waived), (ii) is in violation of any order of any court, arbitrator or governmental body having jurisdiction over the Company or any of its Subsidiaries or their properties or assets, or (iii) is in violation of, or in receipt of written notice that it is in violation of, any statute, rule or regulation of any governmental authority applicable to the Company or any of its Subsidiaries, except in each case as would not, individually or in the aggregate, have or reasonably be expected to result in a Material Adverse Effect. (n) Regulatory Permits. The Company and each of its Subsidiaries possesses all certificates, authorizations and permits issued by the appropriate federal, state, local or foreign regulatory authorities necessary to conduct its business as currently conducted, except as set forth in the SEC Reports, or such that where the failure to possess such permits, individually or in the aggregate, has not and would not have or would not reasonably be expected to result in a Material Adverse Effect (“Material Permits”), and neither the Company nor any of its Subsidiaries has received any notice of Proceedings relating to the revocation or modification of any such Material Permits. (o) Title to Assets. The Company and each of its Subsidiaries has good and marketable title to all tangible personal property owned by it that is material to its business, in each case free and clear of all Liens except such as do not materially affect the value of such property and do not interfere with the use made and proposed to be made of such property by the Company. Any real property and facilities held under lease by the Company and any of its Subsidiaries are held by it under valid, subsisting and enforceable leases with such exceptions as are not material and do not interfere with the use made and proposed to be made of such property and buildings by the Company and its Subsidiaries. 13

(p) Patents and Trademarks. Except as disclosed in Schedule 3.1(p), to the Company’s Knowledge, the Company and each of its Subsidiaries owns, possesses, licenses or has other rights to use, all patents, patent applications, trade and service marks, trade and service xxxx applications and registrations, trade names, trade secrets, inventions, copyrights, licenses, technology, know-how and other intellectual property rights and similar rights necessary or material for use in connection with its businesses as described in the SEC Reports and which the failure to so would have or reasonably be expected to result in a Material Adverse Effect (collectively, the “Intellectual Property Rights”). Except as disclosed in Schedule 3.1(p), to the Company’s Knowledge, none of the Intellectual Property Rights used by the Company or any Subsidiary violates or infringes upon the patent, trademark, copyright, trade secret or other proprietary rights of any Person. There is no pending or, to the Company’s Knowledge, threatened Proceeding or claim by any Person that the Company’s or any Subsidiary’s business as now conducted infringes or otherwise violates any patent, trademark, copyright, trade secret or other proprietary rights of another. To the Company’s Knowledge, there is no existing infringement by another Person of any of the Intellectual Property Rights that would have or would reasonably be expected to result in a Material Adverse Effect. There is no pending or, to the Company’s Knowledge, threatened Proceeding or claim by another Person challenging the Company’s or any Subsidiary’s rights in or to any material Intellectual Property Rights, or challenging inventorship, validity or scope of any such Intellectual Property Rights. The Company has taken reasonable security measures to protect the secrecy, confidentiality and value of all of its and its Subsidiaries’ Intellectual Property Rights, except where failure to do so would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect. None of the technology employed by the Company or any of its Subsidiaries has been obtained or is being used by the Company or any Subsidiary in violation of any contractual obligation binding on the Company or any Subsidiary or, to the Company’s Knowledge, any of its or its Subsidiaries’ officers, directors or employees or otherwise in violation of the rights of any Person, which violations would have or would reasonably be expected to have a Material Adverse Effect. (q) Insurance. The Company and each of its Subsidiaries is insured by insurers of recognized financial responsibility against such losses and risks and in such amounts as the Company believes to be prudent and customary in the businesses and locations in which the Company and the Subsidiaries are engaged. None of the Company or any of its Subsidiaries has received any written notice of cancellation of any such insurance, nor, to the Company’s Knowledge, will it or any Subsidiary be unable to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage from similar insurers as may be necessary to continue its business without a material increase in cost. (r) Transactions With Affiliates and Employees. Except as set forth in the SEC Reports, none of the executive officers or directors of the Company and, to the Company’s Knowledge, none of the employees of the Company is presently a party to any transaction with the Company (other than for services as employees, officers and directors) that would be required to be disclosed pursuant to Item 404 of Regulation S-K promulgated under the Securities Act. (s) Internal Accounting Controls. The Company maintains a system of internal accounting controls sufficient to provide reasonable assurance that (i) transactions are 14

executed in accordance with management’s general or specific authorizations, (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with GAAP and to maintain asset and liability accountability, (iii) access to assets or incurrence of liabilities is permitted only in accordance with management’s general or specific authorization, and (iv) the recorded accountability for assets and liabilities is compared with the existing assets and liabilities at reasonable intervals and appropriate action is taken with respect to any differences. (t) Xxxxxxxx-Xxxxx; Disclosure Controls. The Company is in compliance in all material respects with all of the provisions of the Xxxxxxxx-Xxxxx Act of 2002 which are applicable to it. The Company has established disclosure controls and procedures (as such term is defined in Rule 13a-15(e) and 15d-15(e) under the Exchange Act) for the Company and designed such disclosure controls and procedures to ensure that information required to be disclosed by the Company in the reports it files or submits under the Exchange Act is recorded, processed, summarized and reported, within the time periods specified in the Commission’s rules and forms. The Company’s certifying officers have evaluated the effectiveness of the Company’s disclosure controls and procedures as of the end of the period covered by the Company’s most recently filed periodic report under the Exchange Act (such date, the “Evaluation Date”). The Company presented in its most recently filed periodic report under the Exchange Act the conclusions of the certifying officers about the effectiveness of the disclosure controls and procedures based on their evaluations as of the Evaluation Date. Since the Evaluation Date, there have been no changes in the Company’s internal control over financial reporting (as such term is defined in the Exchange Act) that have materially affected, or are reasonably likely to materially affect, the Company’s internal control over financial reporting. (u) Certain Fees. Except as disclosed in Schedule 3.1(u), no Person will have, as a result of the transactions contemplated by this Agreement, any valid right, interest or claim against or upon the Company or a Purchaser for any commission, fee or other compensation pursuant to any agreement, arrangement or understanding entered into by or on behalf of the Company, other than the Placement Agent with respect to the offer and sale of the Shares and Warrants (which fees are being paid by the Company). The Purchasers shall have no obligation with respect to any fees or with respect to any claim made by or on behalf of other Persons for fees of a type contemplated in this paragraph (u) pursuant to any agreement to which the Company is a party that may be due in connection with the transactions contemplated by the Transaction Documents. The Company shall indemnify, pay, and hold each Purchaser harmless against, any liability, loss or expense (including, without limitation, attorneys’ fees and out-of- pocket expenses) arising in connection with any such right, interest or claim. (v) Private Placement. Assuming the accuracy of the Purchasers’ representations and warranties set forth in Section 3.2 of this Agreement and the accuracy of the information disclosed in the Accredited Investor Questionnaires provided by the Purchasers, no registration under the Securities Act is required for the offer and sale of the Securities by the Company to the Purchasers under the Transaction Documents. The issuance and sale of the Securities hereunder does not contravene the rules and regulations of the Principal Trading Market. (w) Investment Company. The Company is not, and is not an Affiliate of, and immediately after receipt of payment for the Shares and Warrants, will not be or be an Affiliate 15

of, an “investment company” within the meaning of the Investment Company Act of 1940, as amended. The Company shall conduct its business in a manner so that it will not become subject to the Investment Company Act of 1940, as amended. (x) Registration Rights. Other than each of the Purchasers pursuant to the Registration Rights Agreement or as disclosed in Schedule 3.1(x), no Person has any right to cause the Company to effect the registration under the Securities Act of any securities of the Company. (y) Listing and Maintenance Requirements. The Company’s Common Stock is registered pursuant to Section 12(b) or 12(g) of the Exchange Act, and the Company has taken no action designed to terminate the registration of the Common Stock under the Exchange Act, nor has the Company received any notification that the Commission is contemplating terminating such registration. The Company has not, in the 12 months preceding the date hereof, received written notice from any Trading Market on which the Common Stock is listed or quoted to the effect that the Company is not in compliance with the listing or maintenance requirements of such Trading Market. The Company is in compliance with all listing and maintenance requirements of the Principal Trading Market on the date hereof and the issuance of the Securities will not violate any such listing or maintenance requirements. (z) Application of Takeover Protections; Rights Agreements. The Company and the Board of Directors have taken all necessary action, if any, in order to render inapplicable any control share acquisition, business combination, poison pill (including any distribution under a rights agreement) or other similar anti-takeover provision under the Company’s charter documents or the laws of its state of incorporation that is or could reasonably be expected to become applicable to any of the Purchasers as a result of the Purchasers and the Company fulfilling their obligations or exercising their rights under the Transaction Documents, including, without limitation, the Company’s issuance of the Securities and the Purchasers’ ownership of the Securities. (aa) [RESERVED] (bb) No Integrated Offering. Assuming the accuracy of the Purchasers’ representations and warranties set forth in Section 3.2, neither the Company nor, to the Company’s Knowledge, any Person acting on its behalf has, directly or indirectly, at any time within the past six months, made any offers or sales of any Company security or solicited any offers to buy any security under circumstances that would (i) eliminate the availability of the exemption from registration under Regulation D under the Securities Act in connection with the offer and sale by the Company of the Securities as contemplated hereby or (ii) cause the offering of the Securities pursuant to the Transaction Documents to be integrated with prior offerings by the Company for purposes of any applicable law, regulation or stockholder approval provisions, including, without limitation, under the rules and regulations of any Trading Market on which any of the securities of the Company are listed or designated unless such integration would not have or reasonably be expected to result in a Material Adverse Effect. (cc) Tax Matters. The Company and each of its Subsidiaries (i) has accurately and timely prepared and filed (or requested valid extensions thereof) all foreign, federal and state 16

income and all other tax returns, reports and declarations required by any jurisdiction to which it is subject, (ii) has paid all taxes and other governmental assessments and charges that are material in amount, shown or determined to be due on such returns, reports and declarations, except those being contested in good faith, with respect to which adequate reserves have been set aside on the books of the Company and (iii) has set aside on its books provisions reasonably adequate for the payment of all taxes for periods subsequent to the periods to which such returns, reports or declarations apply, except, in the case of clauses (i) and (ii) above, where the failure to so pay or file any such tax, assessment, charge or return would not have or reasonably be expected to result in a Material Adverse Effect. The Company has not received notice of any unpaid taxes in any material amount claimed to be due by the Company or any Subsidiary by the taxing authority of any jurisdiction. (dd) Environmental Matters. To the Company’s Knowledge, none of the Company or any of its Subsidiaries (i) is in violation of any statute, rule, regulation, decision or order of any governmental agency or body or any court, domestic or foreign, relating to the use, disposal or release of hazardous or toxic substances or relating to the protection or restoration of the environment or human exposure to hazardous or toxic substances (collectively, “Environmental Laws”), (ii) owns or operates any real property contaminated with any substance that is in violation of any Environmental Laws, (iii) is liable for any off-site disposal or contamination pursuant to any Environmental Laws, or (iv) is subject to any claim relating to any Environmental Laws; which violation, contamination, liability or claim has had or would have, individually or in the aggregate, a Material Adverse Effect; and there is no pending investigation or, to the Company’s Knowledge, investigation threatened in writing that might lead to such a claim. (ee) No General Solicitation. Neither the Company nor, to the Company’s Knowledge, any Person acting on behalf of the Company has offered or sold any of the Securities by any form of general solicitation or general advertising. (ff) Off Balance Sheet Arrangements. There is no transaction, arrangement, or other relationship between the Company, any Subsidiary and an unconsolidated or other off balance sheet entity that is required to be disclosed by the Company in the SEC Reports and is not so disclosed and would have or reasonably be expected to result in a Material Adverse Effect. (gg) Foreign Corrupt Practices. Neither the Company nor any of its Subsidiaries, nor to the Company’s Knowledge, any agent or other Person acting on behalf of the Company or any of its Subsidiaries, has (i) directly or indirectly, used any funds for unlawful contributions, gifts, entertainment or other unlawful expenses related to foreign or domestic political activity, (ii) made any unlawful payment to foreign or domestic government officials or employees or to any foreign or domestic political parties or campaigns from corporate funds, (iii) failed to disclose fully any contribution made by the Company or any Subsidiary (or made by any Person acting on its behalf of which the Company is aware) which is in violation of law, or (iv) violated in any material respect any provision of the Foreign Corrupt Practices Act of 1977, as amended. 17

(hh) Acknowledgment Regarding Purchasers’ Purchase of Securities. The Company acknowledges and agrees that each of the Purchasers is acting solely in the capacity of an arm’s length purchaser with respect to the Transaction Documents and the transactions contemplated hereby and thereby. The Company further acknowledges that no Purchaser is acting as a financial advisor or fiduciary of the Company (or in any similar capacity) with respect to the Transaction Documents and the transactions contemplated thereby and any advice given by any Purchaser or any of their respective representatives or agents in connection with the Transaction Documents and the transactions contemplated thereby is merely incidental to the Purchasers’ purchase of the Securities. The Company further represents to each Purchaser that the Company’s decision to enter into this Agreement and the other Transaction Documents has been based solely on the independent evaluation of the transactions contemplated hereby by the Company and its representatives. (ii) Regulation M Compliance. The Company has not, and to the Company’s Knowledge no one acting on its behalf has, (i) taken, directly or indirectly, any action designed to cause or to result in the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of any of the Securities, (ii) sold, bid for, purchased, or, paid any compensation for soliciting purchases of, any of the Securities in violation of Regulation M under the Exchange Act, or (iii) paid or agreed to pay to any Person any compensation for soliciting another to purchase any other securities of the Company, other than, in the case of clauses (ii) and (iii), compensation paid to the Placement Agent in connection with the placement of the Shares and Warrants. (jj) PFIC Status. Neither the Company nor any of its Subsidiaries is or intends to become a “passive foreign investment company” within the meaning of Section 1297 of the U.S. Internal Revenue Code of 1986, as amended. (kk) OFAC Status. Neither the Company nor any of its Subsidiaries is and, to the Company’s Knowledge, no director, officer, agent, employee, Affiliate or Person acting on behalf of the Company or any Subsidiary is currently subject to any U.S. sanctions administered by the Office of Foreign Assets Control of the U.S. Treasury Department (“OFAC”); and the Company will not directly or indirectly use the proceeds of the sale of the Securities, or lend, contribute or otherwise make available such proceeds to any joint venture partner or other Person or entity, towards any sales or operations in Cuba, Iran, Syria, Sudan, Myanmar or any other country sanctioned by OFAC or for the purpose of financing the activities of any Person currently subject to any U.S. sanctions administered by OFAC. (ll) FDA. There is no legal or governmental proceeding to which the Company or any Subsidiary is a party or of which any property or assets of the Company or any Subsidiary is the subject, including any proceeding before the United States Food and Drug Administration of the U.S. Department of Health and Human Services (“FDA”) or comparable federal, state, local or non-U.S. governmental bodies (it being understood that the interaction between the Company and the FDA and such comparable governmental bodies relating to the clinical development and product approval process shall not be deemed proceedings for purposes of this representation), which, singularly or in the aggregate, if determined adversely to the Company or any Subsidiary, would have or would reasonably be expected to have a Material Adverse Effect; and to the Company’s Knowledge, no such proceedings are threatened or 18

contemplated by governmental authorities or threatened by others. The Company and each Subsidiary is in compliance with all applicable federal, state, local and non-U.S. laws, regulations, orders and decrees governing its business as prescribed by the FDA, or any other federal, state or non-U.S. agencies or bodies engaged in the regulation of pharmaceuticals, except where noncompliance would not, singularly or in the aggregate, be reasonably likely to have a Material Adverse Effect. All preclinical studies and clinical trials conducted by or on behalf of the Company and any subsidiary, including those necessary to support approval for commercialization of the Company’s or any Subsidiary’s products or product candidates, have been conducted by the Company or any Subsidiary, as applicable, or to the Company’s Knowledge by third parties, in material compliance with all applicable federal, state or non-U.S. laws, rules, orders and regulations. (mm) No Additional Agreements. The Company does not have any agreement or understanding with any Purchaser with respect to the transactions contemplated by the Transaction Documents other than as specified in the Transaction Documents. Section 3.2 Representations and Warranties of the Purchasers. Each Purchaser hereby, for itself and for no other Purchaser, represents and warrants as of the date hereof and as of the Closing Date to the Company and the Placement Agent as follows: (a) Organization; Authority. Such Purchaser is an entity duly organized, validly existing and in good standing under the laws of the jurisdiction of its organization with the requisite corporate, limited liability company or partnership power and authority to enter into and to consummate the transactions contemplated by the applicable Transaction Documents and otherwise to carry out its obligations hereunder and thereunder. The execution and delivery of this Agreement by such Purchaser and performance by such Purchaser of the transactions contemplated by this Agreement have been duly authorized by all necessary corporate or, if such Purchaser is not a corporation, such partnership, limited liability company or other applicable like action, on the part of such Purchaser. Each Transaction Document to which it is a party has been duly executed by such Purchaser, and when delivered by such Purchaser in accordance with the terms hereof, will constitute the valid and legally binding obligation of such Purchaser, enforceable against it in accordance with its terms, except as such enforceability may be limited by applicable bankruptcy, insolvency, reorganization, moratorium, liquidation or similar laws relating to, or affecting generally the enforcement of, creditors’ rights and remedies or by other equitable principles of general application. (b) No Conflicts. The execution, delivery and performance by such Purchaser of this Agreement and the Registration Rights Agreement and the consummation by such Purchaser of the transactions contemplated hereby and thereby will not (i) result in a violation of the organizational documents of such Purchaser, (ii) conflict with, or constitute a default (or an event which with notice or lapse of time or both would become a default) under, or give to others any rights of termination, amendment, acceleration or cancellation of, any agreement, indenture or instrument to which such Purchaser is a party, or (iii) result in a violation of any law, rule, regulation, order, judgment or decree (including federal and state securities laws) applicable to such Purchaser, except in the case of clauses (ii) and (iii) above, for such conflicts, defaults, rights or violations which would not, individually or in the aggregate, reasonably be expected to 19

have a material adverse effect on the ability of such Purchaser to perform its obligations hereunder. (c) Investment Intent. Such Purchaser understands that the Securities are “restricted securities” and have not been registered under the Securities Act or any applicable state securities law and is acquiring the Shares and Warrants and, upon exercise of the Warrants, will acquire the Warrant Shares issuable upon exercise thereof as principal for its own account and not with a view to, or for distributing or reselling such Securities or any part thereof in violation of the Securities Act or any applicable state securities laws, provided, however, that by making the representations herein, such Purchaser does not agree to hold any of the Securities for any minimum period of time and reserves the right, subject to the provisions of this Agreement and the Registration Rights Agreement, at all times to sell or otherwise dispose of all or any part of such Securities pursuant to an effective registration statement under the Securities Act or under an exemption from such registration and in compliance with applicable federal and state securities laws. Such Purchaser is acquiring the Securities hereunder in the ordinary course of its business. Such Purchaser does not presently have any agreement, plan or understanding, directly or indirectly, with any Person to distribute or effect any distribution of any of the Securities (or any securities which are derivatives thereof) to or through any Person; such Purchaser is not a registered broker-dealer under Section 15 of the Exchange Act or an entity engaged in a business that would require it to be so registered as a broker-dealer. (d) Purchaser Status. At the time such Purchaser was offered the Shares and Warrants, it was, and at the date hereof it is, and on each date on which it exercises the Warrants it will be, an “accredited investor” as defined in Rule 501(a) under the Securities Act. (e) General Solicitation. Such Purchaser is not purchasing the Securities as a result of any advertisement, article, notice or other communication regarding the Securities published in any newspaper, magazine or similar media or broadcast over television or radio or presented at any seminar or any other general advertisement. (f) Experience of Such Purchaser. Such Purchaser, either alone or together with its representatives, has such knowledge, sophistication and experience in business and financial matters so as to be capable of evaluating the merits and risks of the prospective investment in the Securities, and has so evaluated the merits and risks of such investment. Such Purchaser is able to bear the economic risk of an investment in the Securities and, at the present time, is able to afford a complete loss of such investment. (g) Access to Information. Such Purchaser acknowledges that it has had the opportunity to review the Disclosure Materials and has been afforded the opportunity to ask such questions as it has deemed necessary of, and to receive answers from, representatives of the Company concerning the terms and conditions of the offering of the Securities. Neither such inquiries nor any other investigation conducted by or on behalf of such Purchaser or its representatives or counsel shall modify, amend or affect such Purchaser’s right to rely on the truth, accuracy and completeness of the Company’s representations and warranties contained in the Transaction Documents. 20

(h) Brokers and Finders. No Person will have, as a result of the transactions contemplated by this Agreement, any valid right, interest or claim against or upon the Company or any Purchaser for any commission, fee or other compensation pursuant to any agreement, arrangement or understanding entered into by or on behalf of such Purchaser. (i) Independent Investment Decision. Such Purchaser has independently evaluated the merits of its decision to purchase Securities pursuant to the Transaction Documents, and such Purchaser confirms that it has not relied on the advice of any other Purchaser’s business and/or legal counsel in making such decision. Such Purchaser understands that nothing in this Agreement or any other materials presented by or on behalf of the Company to the Purchaser in connection with the purchase of the Securities constitutes legal, tax or investment advice. Such Purchaser has consulted such legal, tax and investment advisors as it, in its sole discretion, has deemed necessary or appropriate in connection with its purchase of the Securities. Such Purchaser understands that the Placement Agent has acted solely as the agent of the Company in this placement of the Shares and Warrants and such Purchaser has not relied on the business or legal advice of the Placement Agent or any of its agents, counsel or Affiliates in making its investment decision hereunder, and confirms that none of such Persons has made any representations or warranties to such Purchaser in connection with the transactions contemplated by the Transaction Documents. (j) Reliance on Exemptions. Such Purchaser understands that the Securities are being offered and sold to it in reliance on specific exemptions from the registration requirements of United States federal and state securities laws and that the Company is relying in part upon the truth and accuracy of, and such Purchaser’s compliance with, the representations, warranties, agreements, acknowledgements and understandings of such Purchaser set forth herein in order to determine the availability of such exemptions and the eligibility of such Purchaser to acquire the Securities. (k) No Governmental Review. Such Purchaser understands that no United States federal or state agency or any other government or governmental agency has passed on or made any recommendation or endorsement of the Securities or the fairness or suitability of the investment in the Securities nor have such authorities passed upon or endorsed the merits of the offering of the Securities (l) Residency. Such Purchaser’s residence (if an individual) or offices in which its investment decision with respect to the Securities was made (if an entity) are located at the address immediately below such Purchaser’s name on its signature page hereto. (m) Accuracy of Accredited Investor Questionnaire. The Accredited Investor Questionnaire delivered by such Purchaser in connection with this Agreement is complete and accurate in all respects as of the date of this Agreement and will be correct as of the Closing Date. The Company and each of the Purchasers acknowledge and agree that no party to this Agreement has made or makes any representations or warranties with respect to the transactions contemplated hereby other than those specifically set forth in this Article III and the Transaction Documents. 21

ARTICLE IV OTHER AGREEMENTS OF THE PARTIES Section 4.1 Transfer Restrictions. (a) Compliance with Laws. Notwithstanding any other provision of this Article IV, each Purchaser, severally but not jointly, covenants that the Securities may be disposed of only pursuant to an effective registration statement under, and in compliance with the requirements of, the Securities Act, or pursuant to an available exemption from, or in a transaction not subject to, the registration requirements of the Securities Act, and in compliance with any applicable state and federal securities laws. In connection with any transfer of the Securities other than (i) pursuant to an effective registration statement, (ii) to the Company, (iii) pursuant to Rule 144 (provided that such Purchaser provides the Company with reasonable assurances (in the form of seller and, if applicable, broker representation letters) that the securities may be sold pursuant to such rule) or (iv) in connection with a bona fide pledge as contemplated in Section 4.1(b), the Company may require the transferor thereof to provide to the Company an opinion of counsel selected by the transferor and reasonably acceptable to the Company, the form and substance of which opinion shall be reasonably satisfactory to the Company, to the effect that such transfer does not require registration of such transferred Securities under the Securities Act. As a condition of transfer, any such transferee shall agree in writing to be bound by the terms of this Agreement and the Registration Rights Agreement and shall have the rights of a Purchaser under this Agreement and the Registration Rights Agreement with respect to such transferred Securities. (b) Legends. Certificates evidencing the Securities shall bear any legend as required by the “blue sky” laws of any state and a restrictive legend in substantially the following form, until such time as they are not required under Section 4.1(c): [NEITHER THESE SECURITIES NOR THE SECURITIES ISSUABLE UPON EXERCISE OF THESE SECURITIES HAVE BEEN REGISTERED] [THESE SECURITIES HAVE NOT BEEN REGISTERED] UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “SECURITIES ACT”), OR APPLICABLE STATE SECURITIES LAWS. THE SECURITIES MAY NOT BE OFFERED FOR SALE, SOLD, TRANSFERRED OR ASSIGNED (I) IN THE ABSENCE OF (A) AN EFFECTIVE REGISTRATION STATEMENT FOR THE SECURITIES UNDER THE SECURITIES ACT OR (B) AN AVAILABLE EXEMPTION FROM, OR IN A TRANSACTION NOT SUBJECT TO, THE REGISTRATION REQUIREMENTS OF THE SECURITIES ACT AND IN ACCORDANCE WITH APPLICABLE STATE SECURITIES LAWS OR BLUE SKY LAWS AS EVIDENCED BY A LEGAL OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE COMPANY AND ITS TRANSFER AGENT OR (II) UNLESS SOLD PURSUANT TO RULE 144 UNDER SAID ACT. The Company acknowledges and agrees that a Purchaser may from time to time pledge, and/or grant a security interest in, some or all of the legended Securities in connection with applicable securities laws, pursuant to a bona fide margin agreement in compliance with a bona fide margin loan. Such a pledge would not be subject to approval or consent of the Company and 22

no legal opinion of legal counsel to the pledgee, secured party or pledgor shall be required in connection with the pledge, but such legal opinion shall be required in connection with a subsequent transfer or foreclosure following default by such Purchaser transferee of the pledge. No notice shall be required of such pledge, but such Purchaser’s transferee shall promptly notify the Company of any such subsequent transfer or foreclosure of such legended Securities. Each Purchaser acknowledges that the Company shall not be responsible for any pledges relating to, or the grant of any security interest in, any of the Securities or for any agreement, understanding or arrangement between any Purchaser and its pledgee or secured party. At the appropriate Purchaser’s expense, the Company will execute and deliver such reasonable documentation as a pledgee or secured party of Securities may reasonably request in connection with a pledge or transfer of the Securities, including the preparation and filing of any required prospectus supplement under Rule 424(b)(3) of the Securities Act or other applicable provision of the Securities Act to appropriately amend the list of selling stockholders thereunder. Each Purchaser acknowledges and agrees that, except as otherwise provided in Section 4.1(c), any Securities subject to a pledge or security interest as contemplated by this Section 4.1(b) shall continue to bear the legend set forth in this Section 4.1(b) and be subject to the restrictions on transfer set forth in Section 4.1(a). (c) Removal of Legends. The legend set forth in Section 4.1(b) above shall be removed and the Company shall issue a certificate or book-entry statement without such legend or any other legend to the holder of the applicable Securities upon which it is stamped or issue to such holder by electronic delivery at the applicable balance account at the Depository Trust Company (“DTC”), if (i) such Securities are registered for resale under the Securities Act (provided that, if a Purchaser is selling pursuant to the Registration Statement, such Purchaser agrees to only sell such Securities during such time that the Registration Statement is effective and not withdrawn or suspended, and only as permitted by the Registration Statement), (ii) such Securities are sold or transferred pursuant to Rule 144 (if the transferor is not an Affiliate of the Company), or (iii) such Securities are eligible for sale under Rule 144, without the requirement for the Company to be in compliance with the current public information required under Rule 144 as to such securities and without volume or manner-of-sale restrictions. Following the earlier of (i) the Effective Date or (ii) Rule 144 becoming available for the resale of Securities, without the requirement for the Company to be in compliance with the current public information required under Rule 144 as to such securities and without volume or manner-of-sale restrictions, the Company shall deliver to the Transfer Agent irrevocable instructions that the Transfer Agent shall reissue a certificate representing the applicable Shares or issue a certificate representing the applicable Warrant Shares without legend upon receipt by the Transfer Agent of the legended certificates for such Shares. Any fees (with respect to the Transfer Agent or otherwise) associated with the removal of such legend shall be borne by the Company. Following the Effective Date, or at such earlier time as a legend is no longer required for certain Securities (in which case a Purchaser shall also be required to provide reasonable assurances, in the form of seller and, if applicable, broker representation letters), the Company will no later than three Trading Days following the delivery by a Purchaser to the Company or the Transfer Agent (with notice to the Company) of (i) a legended certificate representing Shares or Warrant Shares (endorsed or with stock powers attached, signatures guaranteed, and otherwise in form necessary to affect the reissuance and/or transfer) or (ii) an Exercise Notice and payment of the applicable exercise price in the manner stated in the Warrants to effect the exercise of such Warrant in accordance with its terms, and an opinion of counsel to the extent required by Section 4.1(a), 23

deliver or cause to be delivered to the transferee of such Purchaser or such Purchaser, as applicable, a certificate representing such Securities that is free from all restrictive and other legends. The Company may not make any notation on its records or give instructions to the Transfer Agent that enlarge the restrictions on transfer set forth in this Section 4.1(c) other than to comply with applicable law. Certificates or book entry statements for Shares or Warrant Shares subject to legend removal hereunder may be transmitted by the Transfer Agent to a Purchaser by crediting the account of such Purchaser’s prime broker with DTC as directed by such Purchaser. (d) Irrevocable Transfer Agent Instructions. The Company shall issue irrevocable instructions to the Transfer Agent, and any subsequent transfer agent, in substantially the form of Exhibit D attached hereto (the “Irrevocable Transfer Agent Instructions”). The Company represents and warrants that no instruction other than the Irrevocable Transfer Agent Instructions referred to in this Section 4.1(d) (or instructions that are consistent therewith) will be given by the Company to the Transfer Agent in connection with this Agreement, and that the Securities shall otherwise be freely transferable on the books and records of the Company as and to the extent provided in this Agreement and the other Transaction Documents and applicable law. The Company acknowledges that a breach by it of its obligations under this Section 4.1(d) will cause irreparable harm to a Purchaser. Accordingly, the Company acknowledges that the remedy at law for a breach of its obligations under this Section 4.1(d) will be inadequate and agrees, in the event of a breach or threatened breach by the Company of the provisions of this Section 4.1(d), that a Purchaser shall be entitled, in addition to all other available remedies, to an order and/or injunction restraining any breach and requiring immediate issuance and transfer, without the necessity of showing economic loss and without any bond or other security being required. (e) Acknowledgement. Each Purchaser, severally but not jointly, acknowledges its primary responsibilities under the Securities Act and accordingly will not sell or otherwise transfer the Securities or any interest therein without complying with the requirements of the Securities Act and applicable law. While the Registration Statement remains effective, each Purchaser hereunder may sell the Shares and Warrant Shares in accordance with the plan of distribution contained in the Registration Statement and if it does so it will comply therewith and with the related prospectus delivery requirements unless an exemption therefrom is available. Each Purchaser, severally and not jointly with the other Purchasers, agrees that if it is notified by the Company in writing at any time that the Registration Statement registering the resale of the Shares or the Warrant Shares is not effective or that the prospectus included in such Registration Statement no longer complies with the requirements of Section 10 of the Securities Act, such Purchaser will refrain from selling such Shares and Warrant Shares until such time as the Purchaser is notified by the Company that such Registration Statement is effective or such prospectus is compliant with Section 10 of the Securities Act, unless such Purchaser is able to, and does, sell such Shares or Warrant Shares pursuant to an available exemption from the registration requirements of Section 5 of the Securities Act. Both the Company and its Transfer Agent, and their respective directors, officers, employees and agents, may rely on this Section 4.1(e) and each Purchaser, severally but not jointly, with the other Purchasers will indemnify and hold harmless each of such persons from any breaches or violations of this Section 4.1(e). 24

(f) Buy-In. If the Company shall fail for any reason or for no reason to issue to a Purchaser un-legended certificates or book-entry statements within three Trading Days after receipt of all documents necessary for the removal of the legend set forth above (the “Deadline Date”), then, in addition to all other remedies available to such Purchaser, if on or after the Trading Day immediately following such three Trading Day period, such Purchaser is required to purchase (in an open market transaction or otherwise) shares of Common Stock to deliver in satisfaction of a sale by the holder of shares of Common Stock that such Purchaser anticipated receiving from the Company without any restrictive legend (a “Buy-In”), then the Company shall, within three Trading Days after such Purchaser’s request and in the Company’s sole discretion, either (i) pay cash to such Purchaser in an amount equal to such Purchaser’s total purchase price (including brokerage commissions, if any) for the shares of Common Stock so purchased (the “Buy-In Price”), at which point the shares of Common Stock held by such Purchaser equal to the number of shares of Common Stock so purchased shall be forfeited to the Company and the Company’s obligation to deliver such certificate or book-entry statement (and to issue such shares of Common Stock) shall terminate, or (ii) promptly honor its obligation to deliver to such Purchaser a certificate or certificates or book-entry statements representing such shares of Common Stock and pay cash to the Purchaser in an amount equal to the excess (if any) of the Buy-In Price over the product of (a) such number of shares of Common Stock, multiplied by (b) the Closing Bid Price on the Deadline Date. A Purchaser shall provide the Company written notice indicating the amounts payable to such Purchaser in respect of the Buy-In, together with applicable confirmations and other evidence reasonably requested by the Company. Section 4.2 Reservation of Common Stock. (a) The Company shall take all action necessary to at all times during the period the Warrants are outstanding have authorized, and reserved for the purpose of issuance from and after the Closing Date, the number of shares of Common Stock issuable upon exercise of the Warrants issued at the Closing (without taking into account any limitations on exercise of the Warrants set forth in the Warrants). (b) The Company shall reserve and keep available at all times during which the Preferred Shares remain outstanding, free of preemptive rights, a sufficient number of shares of Common Stock for the purpose of enabling the Company to issue the Underlying Shares upon conversion of the Preferred Shares pursuant to the Certificate of Designation. The form of Notice of Conversion included in the Certificate of Designation sets forth the totality of the procedures required of the Purchasers in order to convert the Preferred Shares. No additional legal opinion, other information or instructions shall be required of the Purchasers to convert their Preferred Shares. The Company shall honor conversions of the Preferred Shares and shall deliver Underlying Shares in accordance with the terms, conditions and time periods set forth in the Transaction Documents. (c) Acknowledgment of Dilution. The Company acknowledges that the issuance of the Shares may result in dilution of the outstanding shares of Common Stock, which dilution may be substantial under certain market conditions. The Company further acknowledges that its obligations under the Transaction Documents, including without limitation its obligation to issue the Shares pursuant to the Transaction Documents, are unconditional and absolute and 25

not subject to any right of set off, counterclaim, delay or reduction, regardless of the effect of any such dilution or any claim the Company may have against any Purchaser and regardless of the dilutive effect that such issuance may have on the ownership of the other stockholders of the Company. (d) Furnishing of Information. In order to enable the Purchasers to sell the Securities under Rule 144, until the earlier of (i) the date that the Securities cease to be Registrable Securities (as defined in the Registration Rights Agreement) (and for no less than 12 months from the Closing), (ii) the date that is 24 months from the Closing or (iii) a Fundamental Transaction (as defined in the Warrant) pursuant to which the Company is no longer a reporting company under the Exchange Act, the Company shall use its commercially reasonable efforts to timely file (or obtain extensions in respect thereof and file within the applicable grace period) all reports required to be filed by the Company after the date hereof pursuant to the Exchange Act. Except as set forth in clause (iii) above, during such period, if the Company is not required to file reports pursuant to the Exchange Act, it will prepare and furnish to the Purchasers and make publicly available in accordance with Rule 144(c) such information as is required for the Purchasers to sell the Securities under Rule 144. Section 4.3 No Integration. The Company shall not, and shall use its commercially reasonable efforts to ensure that no Affiliate of the Company shall, sell, offer for sale or solicit offers to buy or otherwise negotiate in respect of any security (as defined in Section 2 of the Securities Act) that will be integrated with the offer or sale of the Securities in a manner that would require the registration under the Securities Act of the sale of the Securities to the Purchasers, or that will be integrated with the offer or sale of the Securities for purposes of the rules and regulations of any Trading Market such that it would require stockholder approval prior to the closing of such other transaction unless stockholder approval is obtained before the closing of such subsequent transaction. Section 4.4 Securities Laws Disclosure; Publicity. On or before 9:00 a.m., New York City time, on the Business Day immediately following the date hereof, the Company shall issue a press release (the “Press Release”) reasonably acceptable to the Placement Agent disclosing all material terms of the transactions contemplated hereby. On or before 5:30 p.m., New York City time, on the fourth Trading Day immediately following the execution of this Agreement, the Company will file a Current Report on Form 8-K with the Commission describing the terms of the Transaction Documents (and including as exhibits to such Current Report on Form 8-K the material Transaction Documents (including, without limitation, this Agreement, the form of Warrant and the Registration Rights Agreement)). Notwithstanding the foregoing, the Company shall not publicly disclose the name of any Purchaser or an Affiliate of any Purchaser, or include the name of any Purchaser or an Affiliate of any Purchaser in any press release or filing with the Commission (other than the Registration Statement) or any regulatory agency or Trading Market, without the prior written consent of such Purchaser, except (i) as required by federal securities law in connection with (A) any registration statement contemplated by the Registration Rights Agreement and (B) the filing of final Transaction Documents (including signature pages thereto) with the Commission and (ii) to the extent such disclosure is required by law, request of the Staff of the Commission or Trading Market regulations, in which case the Company shall provide the Purchasers with prior written notice of such disclosure permitted under this subclause (ii). From and after the issuance of the Press Release, no Purchaser shall be in possession of any material, 26

non-public information received from the Company or any of its officers, directors, employees or agents that is not disclosed in the Press Release unless a Purchaser shall have executed a written agreement regarding confidentiality and use of such information. Each Purchaser, severally and not jointly with the other Purchasers, covenants that it will comply with the provisions of any confidentiality or nondisclosure agreement executed by it and, in addition, until such time as the transactions contemplated by this Agreement are required to be publicly disclosed by the Company as described in this Section 4.4 or as otherwise set forth in any such confidentiality or nondisclosure agreement, such Purchaser will maintain the confidentiality of all disclosures made to it in connection with this transaction (including the existence and terms of this transaction). Section 4.5 Shareholder Rights Plan. No claim will be made or enforced by the Company or, with the consent of the Company, any other Person, that any Purchaser is an “Acquiring Person” under any control share acquisition, business combination, poison pill (including any distribution under a rights agreement) or similar anti-takeover plan or arrangement in effect or hereafter adopted by the Company, or that any Purchaser could be deemed to trigger the provisions of any such plan or arrangement, in either case solely by virtue of receiving Securities under the Transaction Documents or under any other written agreement between the Company and the Purchasers. Section 4.6 Non-Public Information. Except with respect to the material terms and conditions of the transactions contemplated by the Transaction Documents, including this Agreement, or as expressly required by any applicable securities law, the Company covenants and agrees that neither it, nor any other Person acting on its behalf, will provide any Purchaser or its agents or counsel with any information regarding the Company that the Company believes constitutes material non-public information without the express written consent of such Purchaser, unless prior thereto such Purchaser shall have executed a written agreement regarding the confidentiality and use of such information. The Company understands and confirms that each Purchaser shall be relying on the foregoing covenant in effecting transactions in securities of the Company. Section 4.7 Use of Proceeds. The Company shall use the net proceeds from the sale of the Shares and Warrants hereunder for working capital and general corporate purposes. Section 4.8 Listing of Securities. In the time and manner required by the Principal Trading Market, the Company shall prepare and file with such Principal Trading Market an additional shares listing application covering all of the Shares and Warrant Shares and shall use its reasonable best efforts to take all steps necessary to cause all of the Shares and Warrant Shares to be approved for listing on the Principal Trading Market as promptly as possible thereafter. Section 4.9 Form D; Blue Sky. The Company agrees to timely file a Form D with respect to the Securities as required under Regulation D and to provide a copy thereof, promptly upon the written request of any Purchaser. The Company, on or before the Closing Date, shall take such action as the Company shall reasonably determine is necessary in order to obtain an exemption for or to qualify the Securities for sale to the Purchasers at the Closing pursuant to this Agreement under applicable securities or “Blue Sky” laws of the states of the United States 27

(or to obtain an exemption from such qualification) and shall provide evidence of such actions promptly upon the written request of any Purchaser. Section 4.10 Indemnification of Purchasers. Subject to the provisions of this Section 4.10, the Company will indemnify and hold each Purchaser and its directors, officers, shareholders, members, partners, employees and agents (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title), each Person who controls such Purchaser (within the meaning of Section 15 of the Securities Act and Section 20 of the Exchange Act), and the directors, officers, shareholders, agents, members, partners or employees (and any other Persons with a functionally equivalent role of a Person holding such titles notwithstanding a lack of such title or any other title) of such controlling persons (each, a “Purchaser Party”) harmless from any and all losses, liabilities, obligations, claims, contingencies, damages, costs and expenses, including all judgments, amounts paid in settlements, court costs and reasonable attorneys’ fees and costs of investigation that any such Purchaser Party may suffer or incur as a result of or relating to (a) any breach of any of the representations, warranties, covenants or agreements made by the Company in this Agreement or in the other Transaction Documents or (ii) any Action instituted against a Purchaser in any capacity, or any Purchaser Party, by any stockholder of the Company who is not an Affiliate of such Purchaser seeking indemnification, with respect to any of the transactions contemplated by the Transaction Documents (unless such Action is based upon a breach of such Purchaser’s representations, warranties or covenants under the Transaction Documents or any other agreement with the Company, or any agreements or understandings such Purchaser may have with any such stockholder or any violations by the Purchaser of state or federal securities laws or any conduct by such Purchaser which constitutes fraud, gross negligence, willful misconduct or malfeasance). Promptly after receipt by any such Person (the “Indemnified Person”) of notice of any demand, claim or circumstances which would or might give rise to a claim or the commencement of any Proceeding or investigation in respect of which indemnity may be sought pursuant to this Section 4.10, such Indemnified Person shall promptly notify the Company in writing and the Company shall assume the defense thereof, including the employment of counsel reasonably satisfactory to such Indemnified Person, and shall assume the payment of all fees and expenses relating to such Proceeding or investigation; provided, however, that the failure of any Indemnified Person so to notify the Company shall not relieve the Company of its obligations hereunder except to the extent that the Company is actually and materially prejudiced by such failure to notify. In any such proceeding, any Indemnified Person shall have the right to retain its own counsel, but the fees and expenses of such counsel shall be at the expense of such Indemnified Person unless: (i) the Company and the Indemnified Person shall have mutually agreed to the retention of such counsel; (ii) the Company shall have failed promptly to assume the defense of such proceeding and to employ counsel reasonably satisfactory to such Indemnified Person in such proceeding; or (iii) in the reasonable judgment of counsel to such Indemnified Person, representation of both parties by the same counsel would be inappropriate due to actual or potential differing interests between them. The Company shall not be liable for any settlement of any proceeding effected without its prior written consent, which consent shall not be unreasonably withheld, delayed or conditioned or to the extent fees or costs incurred pursuant to this Section 4.10 are attributable to the Indemnified Person’s breach of any of the representations, warranties, covenants or agreements made by the Purchasers in this Agreement or the other Transaction Documents. Without the prior written consent of the Indemnified Person, which consent shall not be unreasonably withheld, delayed or conditioned, 28

the Company shall not effect any settlement of any pending or threatened proceeding in respect of which any Indemnified Person is or could have been a party and indemnity could have been sought hereunder by such Indemnified Person, unless such settlement includes an unconditional release of such Indemnified Person from all liability arising out of such proceeding. Section 4.11 Short Sales and Confidentiality After The Date Hereof. Such Purchaser shall not, and shall cause its Trading Affiliates not to, engage, directly or indirectly, in any transactions in the Company’s securities (including, without limitation, any Short Sales involving the Company’s securities) during the period from the date hereof until the earlier of such time as (i) the transactions contemplated by this Agreement are first publicly announced as required by and described in Section 4.4 or (ii) this Agreement is terminated in full pursuant to Section 6.17. Each Purchaser, severally and not jointly with the other Purchasers, covenants that until such time as the transactions contemplated by this Agreement are publicly disclosed by the Company as described in Section 4.4, such Purchaser will maintain the confidentiality of the existence and terms of this transaction and the information included in the Transaction Documents and Disclosure Schedules. Notwithstanding the foregoing, no Purchaser makes any representation, warranty or covenant hereby that it will not engage in Short Sales in the securities of the Company after the time that the transactions contemplated by this Agreement are first publicly announced as described in Section 4.4 (subject to any written agreement between such Purchaser and the Company regarding the confidentiality and use of material non-public information); provided, however, each Purchaser agrees, severally and not jointly with any Purchasers, that they will not enter into any Net Short Sales (as hereinafter defined) from the period commencing on the Closing Date and ending on the earliest of (x) the Effective Date of the initial Registration Statement, (y) the second anniversary of the Closing Date or (z) the date that such Purchaser no longer holds any Securities. For purposes of this Section 4.11, a “Net Short Sale” by any Purchaser shall mean a sale of Common Stock by such Purchaser that is marked as a non-exempt short sale and that is made at a time when there is no equivalent offsetting long position in Common Stock held by such Purchaser. For purposes of determining whether there is an equivalent offsetting position in Common Stock held by the Purchaser, Warrant Shares that have not yet been issued pursuant to the exercise of Warrants shall be deemed to be held long by the Purchaser, and the amount of shares of Common Stock held in a long position shall be all Shares and unexercised Warrant Shares (ignoring any exercise limitations included therein) issuable to such Purchaser on such date, plus any shares of Common Stock or Common Stock Equivalents otherwise then held by such Purchaser. Notwithstanding the foregoing, in the event that a Purchaser is a multi-managed investment vehicle whereby separate portfolio managers manage separate portions of such Purchaser’s assets and the portfolio managers have no direct knowledge of the investment decisions made by the portfolio managers managing other portions of such Purchaser’s assets, the representation set forth above shall apply only with respect to the portion of assets managed by the portfolio manager that have knowledge about the financing transaction contemplated by this Agreement. Moreover, notwithstanding the foregoing, in the event that a Purchaser has sold Securities pursuant to Rule 144 prior to the Effective Date of the initial Registration Statement and the Company has failed to deliver certificates book-entry statements without legends prior to the settlement date for such sale (assuming that such certificates or book-entry statements meet the requirements set forth in Section 4.1(c) for the removal of legends), the provisions of this Section 4.11 shall not prohibit the Purchaser from entering into Net Short Sales for the purpose of delivering shares of Common Stock in settlement of such sale. 29

Section 4.12 Delivery of Shares and Warrants After Closing. The Company shall deliver, or cause to be delivered, the respective Shares and Warrants purchased by each Purchaser to such Purchaser within three Trading Days of the Closing Date. Section 4.13 [RESERVED] Section 4.14 [RESERVED] Section 4.15 No Dilutive Issuances. For a period of 90 days from the Closing Date, the Company may not offer or sell any Common Stock or Common Stock Equivalents for a per- share price (determined on an as-converted basis) of less than $3.55 (adjusted for stock splits, reverse splits, etc.). Notwithstanding the foregoing, this Section 4.15 shall not apply in respect of the issuance of (a) shares of Common Stock or options to employees, consultants, officers or directors of the Company pursuant to any stock or option plan (or a bona fide inducement grant to new employees outside of any such plan) duly adopted by a majority of the non-employee members of the Board of Directors of the Company or a majority of the members of a committee of non-employee directors established for such purpose, (b) securities upon the exercise of or conversion of any convertible securities or warrants issued and outstanding on or prior to the date of or pursuant to this Agreement or any options held by current or former employees or consultants of the Company, (c) shares of Common Stock or securities convertible into Common Stock issued in connection with acquisitions, asset purchases, licenses, joint ventures, technology license agreements, collaborations or strategic transactions involving the Company and other entities approved by the Board of Directors, or (d) securities issued to financial institutions or lessors in connection with credit or lending arrangements, equipment financings or lease arrangements. The Company acknowledges that this covenant is a material inducement to cause the Purchasers to enter into this Agreement. ARTICLE V CONDITIONS PRECEDENT TO CLOSING Section 5.1 5.1 Conditions Precedent to the Obligations of the Purchasers to Purchase Securities. The obligation of each Purchaser to acquire Shares and Warrants at the Closing is subject to the fulfillment to such Purchaser’s satisfaction, on or prior to the Closing Date, of each of the following conditions, any of which may be waived by such Purchaser (as to itself only): (a) Representations and Warranties. The representations and warranties of the Company contained herein shall be true and correct in all material respects (except for those representations and warranties which are qualified as to materiality, in which case such representations and warranties shall be true and correct in all respects) as of the date when made and as of the Closing Date, as though made on and as of such date, except for such representations and warranties that speak as of a specific date. (b) Performance. The Company shall have performed, satisfied and complied in all material respects with all covenants, agreements and conditions required by the Transaction Documents to be performed, satisfied or complied with by it at or prior to the Closing. (c) No Injunction. No statute, rule, regulation, executive order, decree, ruling or injunction shall have been enacted, entered, promulgated or endorsed by any court or 30

governmental authority of competent jurisdiction that prohibits the consummation of any of the transactions contemplated by the Transaction Documents. (d) Consents. The Company shall have obtained in a timely fashion any and all consents, permits, approvals, registrations and waivers necessary for consummation of the purchase and sale of the Securities at the Closing (including all Required Approvals), all of which shall be and remain so long as necessary in full force and effect. (e) Adverse Change. Since the date of execution of this Agreement, no event or series of events shall have occurred that has had or would reasonably be expected to have a Material Adverse Effect. (f) No Suspensions of Trading in Common Stock. The Common Stock shall not have been suspended, as of the Closing Date, by the Commission or the Principal Trading Market from trading on the Principal Trading Market nor shall suspension by the Commission or the Principal Trading Market have been threatened, as of the Closing Date, either (A) in writing by the Commission or the Principal Trading Market or (B) by falling below the minimum listing maintenance requirements of the Principal Trading Market. (g) Company Deliverables. The Company shall have delivered the Company Deliverables in accordance with Section 2.2(a). (h) Compliance Certificate. The Company shall have delivered to each Purchaser a certificate, dated as of the Closing Date and signed by its Chief Executive Officer or its Principal Accounting and Financial Officer, certifying to the fulfillment of the conditions specified in Sections 5.1(a) and (b). (i) Termination. This Agreement shall not have been terminated as to such Purchaser in accordance with Section 6.17 herein. Section 5.2 Conditions Precedent to the Obligations of the Company to sell Securities. The Company’s obligation to sell and issue the Shares and Warrants at the Closing to the Purchasers is subject to the fulfillment to the satisfaction of the Company on or prior to the Closing Date of the following conditions, any of which may be waived by the Company: (a) Representations and Warranties. The representations and warranties made by the Purchasers in Section 3.2 hereof shall be true and correct in all material respects (except for those representations and warranties which are qualified as to materiality, in which case such representations and warranties shall be true and correct in all respects) as of the date when made, and as of the Closing Date as though made on and as of such date, except for representations and warranties that speak as of a specific date. (b) Performance. Such Purchaser shall have performed, satisfied and complied in all material respects with all covenants, agreements and conditions required by the Transaction Documents to be performed, satisfied or complied with by such Purchaser at or prior to the Closing Date. 31

(c) No Injunction. No statute, rule, regulation, executive order, decree, ruling or injunction shall have been enacted, entered, promulgated or endorsed by any court or governmental authority of competent jurisdiction that prohibits the consummation of any of the transactions contemplated by the Transaction Documents. (d) Consents. The Company shall have obtained in a timely fashion any and all consents, permits, approvals, registrations and waivers necessary for consummation of the purchase and sale of the Securities at the Closing (including all Required Approvals), all of which shall be and remain so long as necessary in full force and effect. (e) Purchasers Deliverables. Such Purchaser shall have delivered its Purchaser Deliverables in accordance with Section 2.2(b). (f) Termination. This Agreement shall not have been terminated as to such Purchaser in accordance with Section 6.17 herein. ARTICLE VI MISCELLANEOUS Section 6.1 Fees and Expenses. The Company and each Purchaser, severally and not jointly with any other Purchaser, shall pay the fees and expenses of their respective advisers, counsel, accountants and other experts, if any, and all other expenses incurred by such party in connection with the negotiation, preparation, execution, delivery and performance of this Agreement. The Company shall pay all Transfer Agent fees, stamp taxes and other taxes and duties levied in connection with the sale and issuance of the Securities to the Purchasers. Each Purchaser, severally and not jointly with any other Purchaser, shall be responsible for all other tax liability that may arise as a result of holding or transferring the Securities by it. Notwithstanding the foregoing, the Company shall reimburse the Lead Investor for its fees and expenses incurred in connection with the purchase of the Securities and the registration of such Securities under the Registration Rights Agreement, such fees not to exceed $25,000 in the aggregate. Section 6.2 Entire Agreement. The Transaction Documents, together with the exhibits and schedules thereto, and any confidentiality or nondisclosure agreement entered into prior to the date of this Agreement with respect to the transactions contemplated thereby, contain the entire understanding of the parties with respect to the subject matter hereof and supersede all prior agreements, understandings, discussions and representations, oral or written, with respect to such matters, which the parties acknowledge have been merged into such documents, exhibits and schedules. At or after the Closing, and without further consideration, the Company and the Purchasers will execute and deliver to the other such further documents as may be reasonably requested in order to give practical effect to the intention of the parties under the Transaction Documents. Section 6.3 Notices. Any and all notices or other communications or deliveries required or permitted to be provided hereunder shall be in writing and shall be deemed given and effective on the earliest of (a) the date of transmission, if such notice or communication is delivered via facsimile (provided the sender receives a machine-generated confirmation of 32

successful transmission) at the facsimile number specified in this Section 6.3 prior to 5:00 p.m., New York City time, on a Trading Day, (b) the next Trading Day after the date of transmission, if such notice or communication is delivered via facsimile at the facsimile number specified in this Section 6.3 on a day that is not a Trading Day or later than 5:00 p.m., New York City time, on any Trading Day, (c) the Trading Day following the date of mailing, if sent by U.S. nationally recognized overnight courier service with next day delivery specified, or (d) upon actual receipt by the party to whom such notice is required to be given. The address for such notices and communications shall be as follows: If to the Company: Pieris Pharmaceuticals, Inc. 000 Xxxxx Xxxxxx Xxxxxx, XX 00000 Telephone No.: (000) 000-0000 Attention: Xxxxx Xxxxx, General Counsel Email: xxxxx@xxxxxx.xxx With a copy to (which shall not constitute notice): Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. Xxx Xxxxxxxxx Xxxxxx Xxxxxx, XX 00000 Telephone No.: (000) 000-0000 Attention: Xxxxxxx X. Xxxxx Xxxx X. Xxxxxxx Email: XXXxxxx@xxxxx.xxx XXXxxxxxx@xxxxx.xxx If to a Purchaser: To the address set forth under such Purchaser’s name on the signature page hereof; or such other address as may be designated in writing hereafter, in the same manner, by such Person. Section 6.4 Amendments; Waivers; No Additional Consideration. No provision of this Agreement may be waived, modified, supplemented or amended except in a written instrument signed, in the case of an amendment, by the Company and the Purchasers holding or having the right to acquire a majority of the Shares and the Warrant Shares on a fully-diluted basis at the time of such amendment (which amendment shall be binding on all Purchasers or, in the case of a waiver, by the party against whom enforcement of any such waiver is sought). No waiver of any default with respect to any provision, condition or requirement of this Agreement shall be deemed to be a continuing waiver in the future or a waiver of any subsequent default or a waiver of any other provision, condition or requirement hereof, nor shall any delay or omission of either party to exercise any right hereunder in any manner impair the exercise of any such right. No consideration shall be offered or paid to any Purchaser to amend or consent to a waiver or modification of any provision of any Transaction Document that, by its terms, applies to all 33

Purchasers, unless the same consideration is also offered to all Purchasers who then hold Securities. Section 6.5 Construction. The headings herein are for convenience only, do not constitute a part of this Agreement and shall not be deemed to limit or affect any of the provisions hereof. The language used in this Agreement will be deemed to be the language chosen by the parties to express their mutual intent, and no rules of strict construction will be applied against any party. This Agreement shall be construed as if drafted jointly by the parties, and no presumption or burden of proof shall arise favoring or disfavoring any party by virtue of the authorship of any provisions of this Agreement or any of the Transaction Documents. Section 6.6 Successors and Assigns. The provisions of this Agreement shall inure to the benefit of and be binding upon the parties and their successors and permitted assigns. This Agreement, or any rights or obligations hereunder, may not be assigned by the Company without the written consent of Purchasers holding or having the right to acquire a majority of the Shares and the Warrant Shares on a fully-diluted basis at the time of such consent except to a successor in the event of a Fundamental Transaction. Any Purchaser may assign its rights hereunder in whole or in part to any Person to whom such Purchaser assigns or transfers any Securities in compliance with the Transaction Documents and applicable law, provided that such transferee shall agree in writing to be bound, with respect to the transferred Securities, by the terms and conditions of this Agreement that apply to the “Purchasers”. Section 6.7 No Third-Party Beneficiaries. This Agreement is intended for the benefit of the parties hereto and their respective successors and permitted assigns and is not for the benefit of, nor may any provision hereof be enforced by, any other Person, except (i) the Placement Agent is an intended third party beneficiary of Article III hereof and (ii) each Purchaser Party is an intended third party beneficiary of Section 4.10. Section 6.8 Survival. Subject to applicable statute of limitations, the representations, warranties agreements and covenants contained herein shall survive the Closing and the delivery of the Securities and any confidentiality or nondisclosure obligations set forth in any agreement entered into prior to the date of this Agreement with respect to the transactions contemplated by the Transaction Documents shall survive according to the terms of such agreements. Section 6.9 Execution. This Agreement may be executed in two or more counterparts, all of which when taken together shall be considered one and the same agreement and shall become effective when counterparts have been signed by each party and delivered to the other party, it being understood that both parties need not sign the same counterpart. In the event that any signature is delivered by facsimile transmission, or by e-mail delivery of a “.pdf” format data file, such signature shall create a valid and binding obligation of the party executing (or on whose behalf such signature is executed) with the same force and effect as if such facsimile signature page were an original thereof. Section 6.10 Severability. If any provision of this Agreement is held to be invalid or unenforceable in any respect, the validity and enforceability of the remaining terms and provisions of this Agreement shall not in any way be affected or impaired thereby and the parties 34

will attempt to agree upon a valid and enforceable provision that is a reasonable substitute therefor, and upon so agreeing, shall incorporate such substitute provision in this Agreement. Section 6.11 Replacement of Securities. If any certificate or instrument evidencing any Securities is mutilated, lost, stolen or destroyed, the Company shall issue or cause to be issued in exchange and substitution for and upon cancellation thereof, or in lieu of and substitution therefor, a new certificate or instrument, but only upon receipt of evidence reasonably satisfactory to the Company and the Transfer Agent of such loss, theft or destruction and the execution by the holder thereof of a customary lost certificate affidavit of that fact and an agreement to indemnify and hold harmless the Company and the Transfer Agent for any losses in connection therewith or, if required by the Transfer Agent, a bond in such form and amount as is required by the Transfer Agent. The applicants for a new certificate or instrument under such circumstances shall also pay any reasonable third-party costs associated with the issuance of such replacement Securities. If a replacement certificate or instrument evidencing any Securities is requested due to a mutilation thereof, the Company may require delivery of such mutilated certificate or instrument as a condition precedent to any issuance of a replacement. Section 6.12 Remedies. In addition to being entitled to exercise all rights provided herein or granted by law, including recovery of damages, each of the Purchasers and the Company will be entitled to specific performance under the Transaction Documents. The parties agree that monetary damages may not be adequate compensation for any loss incurred by reason of any breach of obligations described in the foregoing sentence and hereby agree to waive in any Action for specific performance of any such obligation (other than in connection with any Action for a temporary restraining order) the defense that a remedy at law would be adequate. Section 6.13 Payment Set Aside. To the extent that the Company makes a payment or payments to any Purchaser pursuant to any Transaction Document or a Purchaser enforces or exercises its rights thereunder, and such payment or payments or the proceeds of such enforcement or exercise or any part thereof are subsequently invalidated, declared to be fraudulent or preferential, set aside, recovered from, disgorged by or are required to be refunded, repaid or otherwise restored to the Company, a trustee, receiver or any other Person under any law (including, without limitation, any bankruptcy law, state or federal law, common law or equitable cause of action), then to the extent of any such restoration the obligation or part thereof originally intended to be satisfied shall be revived and continued in full force and effect as if such payment had not been made or such enforcement or setoff had not occurred. Section 6.14 Adjustments in Share Numbers and Prices. In the event of any stock split, subdivision, dividend or distribution payable in shares of Common Stock (or other securities or rights convertible into, or entitling the holder thereof to receive directly or indirectly shares of Common Stock), combination or other similar recapitalization or event occurring after the date hereof and prior to the Closing, each reference in any Transaction Document to a number of shares or a price per share shall be deemed to be amended to appropriately account for such event. Section 6.15 Governing Law. All questions concerning the construction, validity, enforcement and interpretation of this Agreement shall be governed by and construed and enforced in accordance with the internal laws of the State of New York, without regard to the 35

principles of conflicts of law thereof. Each party agrees that all Proceedings concerning the interpretations, enforcement and defense of the transactions contemplated by this Agreement and any other Transaction Documents (whether brought against a party hereto or its respective Affiliates, employees or agents) shall be commenced exclusively in the New York Courts. Each party hereto hereby irrevocably submits to the exclusive jurisdiction of the New York Courts for the adjudication of any dispute hereunder or in connection herewith or with any transaction contemplated hereby or discussed herein (including with respect to the enforcement of any of the Transaction Documents), and hereby irrevocably waives, and agrees not to assert in any Proceeding, any claim that it is not personally subject to the jurisdiction of any such New York Court, or that such Proceeding has been commenced in an improper or inconvenient forum. Each party hereto hereby irrevocably waives personal service of process and consents to process being served in any such Proceeding by mailing a copy thereof via registered or certified mail or overnight delivery (with evidence of delivery) to such party at the address in effect for notices to it under this Agreement and agrees that such service shall constitute good and sufficient service of process and notice thereof. Nothing contained herein shall be deemed to limit in any way any right to serve process in any manner permitted by law. EACH PARTY HERETO HEREBY IRREVOCABLY WAIVES, TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW, ANY AND ALL RIGHT TO TRIAL BY JURY IN ANY LEGAL PROCEEDING ARISING OUT OF OR RELATING TO THIS AGREEMENT OR THE TRANSACTIONS CONTEMPLATED HEREBY. Section 6.16 Waiver of Conflicts. Each Purchaser acknowledges that Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C., outside general counsel to the Company, has in the past performed and is or may now or in the future represent one or more Purchasers or their Affiliates in matters unrelated to the transactions contemplated by the this Agreement, including representation of such Purchasers or their Affiliates in matters of a similar nature to the transactions contemplated by this Agreement. The applicable rules of professional conduct require that Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. inform the Purchasers hereunder of this representation and obtain their consent. Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. has served as outside general counsel to the Company and has negotiated the terms of this Agreement solely on behalf of the Company. Each Purchaser hereby (a) acknowledges that they have had an opportunity to ask for and have obtained information relevant to such representation; (b) acknowledges that with respect to the transactions contemplated by this Agreement, Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C. has represented solely the Company, and not any Purchaser or any stockholder, director or employee of the Company or any Purchaser; and (c) gives its informed consent to Mintz, Levin, Cohn, Ferris, Glovsky and Popeo, P.C.’s representation of the Company in the transactions contemplated by this Agreement. Section 6.17 Termination. This Agreement may be terminated and the sale and purchase of the Shares and the Warrants abandoned at any time prior to the Closing by either the Company or any Purchaser (with respect to itself only) upon written notice to the other, if the Closing has not been consummated on or prior to 5:00 p.m., New York City time, on the Outside Date; provided, however, that the right to terminate this Agreement under this Section 6.17 shall not be available to any Person whose failure to comply with its obligations under this Agreement has been the cause of or resulted in the failure of the Closing to occur on or before such time. Nothing in this Section 6.17 shall be deemed to release any party from any liability for any 36

breach by such party of the terms and provisions of this Agreement or the other Transaction Documents or to impair the right of any party to compel specific performance by any other party of its obligations under this Agreement or the other Transaction Documents. In the event of a termination pursuant to this Section 6.17, the Company shall promptly notify all non-terminating Purchasers. Upon a termination in accordance with this Section 6.17, the Company and the terminating Purchaser(s) shall not have any further obligation or liability (including arising from such termination) to the other, and no Purchaser will have any liability to any other Purchaser under the Transaction Documents as a result therefrom. The Company and any Purchaser(s) may extend the term of this Agreement in accordance with the amendment provisions of Section 6.4 herein. [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK] 37

IN WITNESS WHEREOF, the parties hereto have caused this Securities Purchase Agreement to be duly executed by their respective authorized signatories as of the date first indicated above. PIERIS PHARMACEUTICALS, INC. By: /s/ Xxxxxxx Xxxxx Name: Xxxxxxx Xxxxx Title: CEO [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK] [SIGNATURE PAGES FOR PURCHASERS FOLLOW] [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: AQUILO CAPITAL, L.P. By: /s/ Xxxx Xxxxxxxxxx Name: Xxxx Xxxxxxxxxx Title: Managing Member, Aquilo Capital Management, LLC, General Partner Aggregate Purchase Price (Subscription Amount): $4,000,001.55 Number and Type of Shares to be Acquired: Common Stock: 1,126,761 Preferred Stock: N/A Warrant Shares: 1,126,761 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: Biotechnology Value Fund, L.P. By: /s/ Xxxx Xxxxxxx Name: Xxxx Xxxxxxx Title: President BVF Inc., GP BVF Partners L.P. Aggregate Purchase Price (Subscription Amount): $6,375,800.00 Number and Type of Shares to be Acquired: Common Stock: N/A Preferred Stock: 1,796 Warrant Shares: 1,796,000 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: Biotechnology Value Fund II, L.P. By: /s/ Xxxx Xxxxxxx Name: Xxxx Xxxxxxx Title: President BVF Inc., GP BVF Partners L.P. Aggregate Purchase Price (Subscription Amount): $5,129,750.00 Number and Type of Shares to be Acquired: Common Stock: N/A Preferred Stock: 1,445 Warrant Shares: 1,445,000 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: Biotechnology Value Trading Fund OS, L.P. By: /s/ Xxxx Xxxxxxx Name: Xxxx Xxxxxxx Title: President BVF Inc., GP BVF Partners L.P., Sole Member BVF Partners OS, Ltd. Aggregate Purchase Price (Subscription Amount): $940,750.00 Number and Type of Shares to be Acquired: Common Stock: N/A Preferred Stock: 265 Warrant Shares: 265,000 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: MSI BVF SPV L.L.C. By: /s/ Xxxx Xxxxxxx Name: Xxxx Xxxxxxx Title: President BVF Inc., GP BVF Partners L.P., Attorney-In-Fact Aggregate Purchase Price (Subscription Amount): $56,800.00 Number and Type of Shares to be Acquired: Common Stock: N/A Preferred Stock: 16 Warrant Shares: 16,000 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: EcoR1 Capital Fund, LP By: /s/ Xxxx Xxxxxxxx Name: Xxxx Xxxxxxxx Title: Manger, EcoR1 Capital LLC, as General Partner Aggregate Purchase Price (Subscription Amount): $1,508,402.10 Number and Type of Shares to be Acquired: Common Stock: 424,902 Preferred Stock: n/a Warrant Shares: 424,902 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: EcoR1 Capital Fund Qualified LP By: /s/ Xxxx Xxxxxxxx Name: Xxxx Xxxxxxxx Title: Manger, EcoR1 Capital LLC, as General Partner Aggregate Purchase Price (Subscription Amount): $7,491,600.50 Number and Type of Shares to be Acquired: Common Stock: 2,110,310 Preferred Stock: n/a Warrant Shares: 2,110,310 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: Samsara BioCapital, L.P. By: Samsara BioCapital GP, LLC By: /s/ Xxxxxxxx Xxxxxxxx, MD, PhD Name: Xxxxxxxx Xxxxxxxx, MD, PhD Title: Managing Member Aggregate Purchase Price (Subscription Amount): $2,500,002.30 Number and Type of Shares to be Acquired: Common Stock: 704,226 Preferred Stock: n/a Warrant Shares: 704,226 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above): [Signature Page to Securities Purchase Agreement]

NAME OF PURCHASER: Citadel Multi-Strategy Equities Master Fund Ltd. By: Citadel Advisors LLC, its portfolio manager By: /s/ Xxxxxxxx Xxxxxxx Name: Xxxxxxxx Xxxxxxx Title: Authorized Signatory Aggregate Purchase Price (Subscription Amount): $4,000,001.55 Number and Type of Shares to be Acquired: Common Stock: 1,126,761 Preferred Stock: n/a Warrant Shares: 1,126,761 Tax ID No.: Address for Notice/Residency of Purchaser: Delivery Instructions (if different than above):

EXHIBITS A: Form of Warrant B: Form of Registration Rights Agreement C: Form of Opinion of Company Counsel D: Form of Irrevocable Transfer Agent Instructions E: Form of Certificate of Designation F: Accredited Investor Questionnaire

EXHIBIT A Form of Warrant 49

EXHIBIT B Form of Registration Rights Agreement 50

EXHIBIT C-1 Form of Opinion of Company Counsel 51

EXHIBIT C-2 Form of Opinion of Nevada Counsel

EXHIBIT D Irrevocable Transfer Agent Instructions

EXHIBIT E Form of Certificate of Designation

EXHIBIT F ACCREDITED INVESTOR QUESTIONNAIRE