AZ-001 (Staccato prochlorperazine). We are developing AZ-001 to treat patients suffering from acute migraine headaches. According to the National Headache Foundation, approximately 13 million people in the United States have been diagnosed with migraine headaches. In October 2005, we completed a 75 patient, multi-center, double-blind, placebo-controlled Phase IIa clinical trial in patients suffering from moderate to severe acute migraine headaches. Two doses of AZ-001 (5 mg and 10 mg) were studied in the clinical trial, and both doses exhibited positive trends when compared to placebo. AZ-001 was generally well tolerated, and there were no serious adverse events in the trial. We plan to initiate a Phase IIb clinical trial of AZ-001 in the first half of 2006

Exhibit 1.1

_____ Shares¹

Alexza Pharmaceuticals, Inc.

Common Stock

PURCHASE AGREEMENT

_____________________, 2006

PIPER JAFFRAY & CO.
PACIFIC GROWTH EQUITIES, LLC
RBC CAPITAL MARKETS CORPORATION
JMP SECURITIES LLC
   As Representatives of the several
   Underwriters named in Schedule I hereto
c/o Piper Jaffray & Co.
800 Nicollet Mall
Minneapolis, Minnesota 55402

Ladies and Gentlemen:

     Alexza Pharmaceuticals, Inc., a Delaware corporation (the “Company") proposes to sell to the several Underwriters named in Schedule I hereto (the “Underwriters”) an aggregate of ______ shares (the “Firm Shares”) of Common Stock, $0.0001 par value per share (the “Common Stock”), of the Company. The Firm Shares consist of ______ authorized but unissued shares of Common Stock to be issued and sold by the Company. The Company has also granted to the several Underwriters an option to purchase up to ______ additional shares of Common Stock on the terms and for the purposes set forth in Section 3 hereof (the “Option Shares”). The Firm Shares and any Option Shares purchased pursuant to this Purchase Agreement are herein collectively called the “Securities.”

     The Company hereby confirms its agreement with respect to the sale of the Securities to the several Underwriters, for whom you are acting as representatives (the “Representatives”).

     1. Registration Statement and Prospectus. A registration statement on Form S-1 (File No. 333-___) with respect to the Securities, including a preliminary form of prospectus, has been prepared by the Company in conformity with the requirements of the Securities Act of 1933, as amended (the “Act”), and the rules and regulations (“Rules and

Regulations”) of the Securities and Exchange Commission (the “Commission”) thereunder and has been filed with the Commission; one or more amendments to such registration statement have also been so prepared and have been, or will be, so filed; and, if the Company has elected to rely upon Rule 462(b) of the Rules and Regulations (“Rule 462(b)”) to increase the size of the offering registered under the Act, the Company will prepare and file with the Commission a registration statement with respect to such increase pursuant to Rule 462(b). Copies of such registration statement(s) and amendments and each related preliminary prospectus have been delivered to you.

     If the Company has elected not to rely upon Rule 430A of the Rules and Regulations, (“Rule 430A”) the Company has prepared and will promptly file an amendment to the registration statement and an amended prospectus. If the Company has elected to rely upon Rule 430A, it will prepare and file a prospectus pursuant to Rule 424(b) of the Rules and Regulations (“Rule 424(b)”) that discloses the information previously omitted from the prospectus in reliance upon Rule 430A. Each part of such registration statement as amended at the time it is or was declared effective by the Commission, and, in the event of any amendment thereto after the effective date, each part of such registration statement as so amended (but only from and after the effectiveness of such amendment, or the date it is first used after effectiveness of the registration statement, in the case of information contained in a form of prospectus filed with the Commission pursuant to Rule 424(b) and deemed to be part of the registration statement pursuant to Rule 430C of the Rules and Regulations (“Rule 430C”)), including a registration statement (if any) filed pursuant to Rule 462(b) increasing the size of the offering registered under the Act, information (if any) deemed to be part of the registration statement at the time of effectiveness pursuant to Rule 430A(b) and information (if any) contained in a form of prospectus required to be filed with the Commission pursuant to Rule 424(b) and deemed to be part of and included in the registration statement on the date it is first used after effectiveness in accordance with Rule 430C, is hereinafter called the “Registration Statement.” The prospectus included in the Registration Statement at the time it is or was declared effective by the Commission is hereinafter called the “Prospectus,” except that if any prospectus filed by the Company with the Commission pursuant to Rule 424(b) or any other such prospectus provided to the Underwriters by the Company for use in connection with the offering of the Securities (whether or not required to be filed by the Company with the Commission pursuant to Rule 424(b)) but not including a “free writing prospectus” as defined in Rule 405 of the Rules and Regulations (“Rule 405”) differs from the prospectus on file at the time the Registration Statement is or was declared effective by the Commission, the term “Prospectus” shall refer to such differing prospectus from and after the time such prospectus is filed with the Commission or transmitted to the Commission for filing pursuant to such Rule 424(b) or from and after the time of its first use within the meaning of the Rules and Regulations. The term “Preliminary Prospectus” as used herein means the preliminary prospectus included in the Registration Statement prior to the time it becomes or became effective under the Act and subject to completion as described in Rule 430A in the form first used to make offers and included in the Registration Statement filed on __________________, 2006. All references in this Agreement to amendments or supplements to the Registration Statement or the Prospectus shall be deemed to include the filing of any prospectus supplement pursuant to Rule 424(b).

     2. Representations and Warranties of the Company.

          (a) The Company represents and warrants to, and agrees with, the several Underwriters as follows:

            (i) No order preventing or suspending the use of any Preliminary Prospectus has been issued by the Commission and the Preliminary Prospectus, at the time of filing thereof or the time of first use within the meaning of the Rules and Regulations, complied in all material respects with the applicable requirements of the Securities Act and the Rules and Regulations and did not contain an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading; except that the foregoing shall not apply to statements in or omissions from any Preliminary Prospectus in reliance upon, and in conformity with, written information furnished to the Company by you, or by any Underwriter through you, specifically for use in the preparation thereof.

            (ii) As of the time any part of the Registration Statement (or any post-effective amendment thereto, including a registration statement (if any) filed pursuant to Rule 462(b) increasing the size of the offering registered under the Act) became effective, upon the filing or first use within the meaning of the Rules and Regulations of the Prospectus (or any supplement to the Prospectus) and at the First Closing Date and Second Closing Date (as hereinafter defined), (A) the Registration Statement and the Prospectus (in each case, as so amended and/or supplemented) conformed or will conform in all material respects to the requirements of the Act and the Rules and Regulations, (B) the Registration Statement (as so amended) did not or will not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein not misleading, and (C) the Prospectus (as so supplemented) did not or will not include an untrue statement of a material fact or omit to state a material fact required to be stated therein or necessary to make the statements therein, in light of the circumstances in which they are or were made, not misleading; except that each of the foregoing shall not apply to statements in or omissions from any such document in reliance upon, and in conformity with, written information furnished to the Company by you, or by any Underwriter through you, specifically for use in the preparation thereof. If the Registration Statement has been declared effective by the Commission, no stop order suspending the effectiveness of the Registration Statement has been issued, and, to the Company’s knowledge, no proceeding for that purpose has been initiated or threatened by the Commission.

            (iii) The Issuer-Represented General Free Writing Prospectus(es) issued on or after the date of the Preliminary Prospectus and at or prior to the Time of Sale and the Statutory Prospectus, all considered together (collectively, the “Time of Sale Disclosure Package”), does not include and did not include as of the Time of

Sale any untrue statement of a material fact or omit or omitted as of the Time of Sale to state any material fact necessary in order to make the statements therein, in the light of the circumstances under which they were made, not misleading. The preceding sentence does not apply to statements in or omissions from any Statutory Prospectus included in the Registration Statement or any Issuer-Represented Free Writing Prospectus based upon and in conformity with written information furnished to the Company by you or by any Underwriter through you specifically for use therein. As used in this paragraph and elsewhere in this Agreement:

            (1) “Time of Sale” means ___:00 **[a/p]m (Eastern time) on the date of this Agreement

            (2) “Statutory Prospectus” as of any time means the prospectus that is included in the Registration Statement immediately prior to the Time of Sale. For purposes of this definition, information contained in a form of prospectus that is deemed retroactively to be a part of the Registration Statement pursuant to Rule 430A shall be considered to be included in the Statutory Prospectus as of the actual time that form of prospectus is filed with the Commission pursuant to Rule 424(b).

            (3) “Issuer-Represented Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433 of the Rules and Regulations (“Rule 433”), relating to the Securities that (A) is required to be filed with the Commission by the Company, or (B) is exempt from filing pursuant to Rule 433(d)(5)(i) because it contains a description of the Securities or of the offering that does not reflect the final terms or pursuant to Rule 433(d)(8)(ii) because it is a “bona fide electronic road show,” as defined in Rule 433 which is made available by the Company without restriction, in each case in the form filed or required to be filed with the Commission or, if not required to be filed, in the form retained in the Company’s records pursuant to Rule 433(g).

            (4) “Issuer-Represented General Free Writing Prospectus” means any Issuer-Represented Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being specified in Schedule II to this Agreement, and does not include a “bona fide electronic road show,” as defined in Rule 433.

            (5) “Issuer-Represented Limited-Use Free Writing Prospectus” means any Issuer-Represented Free Writing Prospectus that is not an Issuer-Represented General Free Writing Prospectus. The term Issuer-Represented Limited-Use Free Writing Prospectus also includes any “bona fide electronic road show,” as defined in Rule 433, that is made available without restriction pursuant to Rule 433(d)(8)(ii), even though not required to be filed with the Commission.

            (iv) (A) Each Issuer-Represented Free Writing Prospectus, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities or until any earlier date that the issuer notified or notifies the Representatives as described in Section 4(a)(iii)(B), did not, does not and will not include any information that conflicted, conflicts or will conflict with the information contained in the Registration Statement. The foregoing sentence does not apply to statements in or omissions from any Issuer-Represented Free Writing Prospectus based upon and in conformity with written information furnished to the Company by you or by any Underwriter through you specifically for use therein.

                    (B) (1) At the time of filing the Registration Statement and (2) at the date hereof, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, including the Company in the preceding three years not having been convicted of a felony or misdemeanor or having been made the subject of a judicial or administrative decree or order as described in Rule 405, nor an “excluded issuer” as defined in Rule 164 of the Rules and Regulations (“Rule 164”).

                    (C) Each Issuer-Represented Free Writing Prospectus satisfied, as of its issue date and at all subsequent times through the completion of the public offer and sale of the Securities, all other conditions to use thereof as set forth in Rules 164 and 433.

            (v) The financial statements of the Company, together with the related notes, set forth in the Registration Statement, the Time of Sale Disclosure Package and Prospectus comply in all material respects with the requirements of the Act and fairly present the financial condition of the Company as of the dates indicated and the results of operations and changes in cash flows for the periods therein specified in conformity with generally accepted accounting principles in the United States consistently applied throughout the periods involved; and the other financial information included in the Registration Statement, the Time of Sale Disclosure Package and Prospectus present fairly the information shown thereby. No other financial statements or financial information is required to be included in the Registration Statement, the Time of Sale Disclosure Package or the Prospectus. Ernst & Young LLP, which has expressed its opinion with respect to the financial statements filed as a part of the Registration Statement and included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, is (x) an independent public accounting firm within the meaning of the Act and the Rules and Regulations, (y) a registered public accounting firm (as defined in Section 2(a)(12) of the Sarbanes-Oxley Act of 2002 (the “Sarbanes-Oxley Act”)) and (z) not in violation of the auditor independence requirements of the Sarbanes-Oxley Act. Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, there are no material off-balance sheet transactions, arrangements, obligations (including contingent obligations), or any other relationships with unconsolidated entities or other persons, that may have a material current or, to the Company’s knowledge, future effect on the Company’s financial condition, results of operations, liquidity,

capital expenditures, capital resources or significant components of revenue or expenses.

            (vi) The Company has been duly organized and is validly existing as a corporation in good standing under the laws of its jurisdiction of incorporation. The Company has full corporate power and authority to own its properties and conduct its business as currently being conducted and as described in the Registration Statement, the Time of Sale Disclosure Package and Prospectus, and is duly qualified to do business as a foreign corporation in good standing in each jurisdiction in which it owns or leases real property or in which the conduct of its business makes such qualification necessary and in which the failure to so qualify would reasonably be expected to have a material adverse effect upon, or change in, the general affairs, business, prospects, properties, operations, condition (financial or otherwise) or results of operations of the Company (“Material Adverse Effect” or “Material Adverse Change”).

            (vii) Except as disclosed in the Time of Sale Disclosure Package and in the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, the Company has not incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there has not been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants), or any material change in the short-term or long-term debt, or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock (other than grants of stock options under the Company’s stock option plans existing on the date hereof) of the Company, or any Material Adverse Change.

            (viii) Except as disclosed in the Time of Sale Disclosure Package and the Prospectus, there is not pending or, to the knowledge of the Company, threatened or contemplated, any action, suit or proceeding to which the Company is a party or of which any property or assets of the Company is the subject before or by any court or Governmental Authority (as defined below), or any arbitrator, which, individually or in the aggregate, would reasonably be expected to result in any Material Adverse Change. There are no actions, suits or proceedings to which the Company is a party or of which any property or assets of the Company is the subject that are required to be disclosed in the Registration Statement, Time of Sale Disclosure Package and Prospectus by the Act or by the Rules and Regulations that have not been so disclosed.

            (ix) There are no statutes or regulations applicable to the Company, or contracts or documents of the Company that are required to be described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus or be filed as exhibits to the Registration Statement by the Act or by the Rules and Regulations that have not been so described or filed.

            (x) This Agreement has been duly authorized, executed and delivered by the Company, and constitutes a valid, legal and binding obligation of the Company, enforceable in accordance with its terms, except as rights to indemnity hereunder may be limited by federal or state securities laws and except as such enforceability may be limited by bankruptcy, insolvency, reorganization or similar laws affecting the rights of creditors generally and subject to general principles of equity. The execution, delivery and performance of this Agreement and the consummation of the transactions herein contemplated will not (i) result in a breach or violation of any of the terms or provisions of, or constitute a default under, or result in the creation or imposition of any lien, charge or encumbrance upon any property or assets of the Company pursuant to any agreement or instrument to which the Company is a party or by which the Company is bound or to which any of the property or assets of the Company is subject, (ii) result in any violation of the provisions of the Company’s charter or by laws or (iii) result in the violation of any law or statute, or any order, rule, regulation, judgment or decree of any court or arbitrator or federal, state, local or foreign governmental agency or regulatory authority having jurisdiction over the Company or any of its properties or assets (each, a “Governmental Authority”). No consent, approval, authorization or order of, or filing with, any court or Governmental Authority is required for the execution, delivery and performance of this Agreement or for the consummation of the transactions contemplated hereby, including the issuance or sale of the Securities by the Company, except such as may be required under the Act, the rules of the National Association of Securities Dealers, Inc. or state securities or blue sky laws; and the Company has full power and authority to enter into this Agreement and to authorize, issue and sell the Securities as contemplated by this Agreement.

            (xi) All of the issued and outstanding shares of capital stock of the Company, including the outstanding shares of Common Stock, are duly authorized and validly issued, fully paid and nonassessable, have been issued in compliance with all federal and state securities laws, were not issued in violation of or subject to any preemptive rights or other rights to subscribe for or purchase securities that have not been waived in writing (a copy of which has been delivered to counsel to the Representatives), and the holders thereof are not subject to personal liability by reason of being such holders; the Securities which may be sold hereunder by the Company have been duly authorized and, when issued, delivered and paid for in accordance with the terms of this Agreement, will have been validly issued and will be fully paid and nonassessable, and the holders thereof will not be subject to personal liability by reason of being such holders; and the capital stock of the Company, including the Common Stock, conforms to the description thereof in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus.

Except as otherwise disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, there are no preemptive rights or other rights to subscribe for or to purchase, or any restriction upon the voting or transfer of, any shares of Common Stock pursuant to the Company’s charter, by-laws or any agreement or other instrument to which the Company is a party or by which the Company is bound. Neither the filing of the Registration Statement nor the offering or sale of the Securities as contemplated by this Agreement gives rise to any rights for or relating to the registration of any shares of Common Stock or other securities of the Company that have not been waived in writing (a copy of which has been delivered to counsel to the Representatives). Except as disclosed in the Registration Statement, in the Time of Sale Disclosure Package and in the Prospectus, there are no options, warrants, agreements, contracts or other rights in existence to purchase or acquire from the Company any shares of the capital stock of the Company (other than options to purchase common stock granted pursuant to the Company’s stock option plans existing on the date hereof subsequent to the dates set forth therein). The Company has an authorized and outstanding capitalization as set forth in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus.

            (xii) The Company possesses all licenses, certificates, permits and other authorizations issued by, and have made all declarations and filings with, the appropriate Governmental Authorities that are necessary for the ownership or lease of its properties or the conduct of its business; the Company has not received notice of any revocation or modification of any such license, certificate, permit or authorization and have no reason to believe that any such license, certificate, permit or authorization will not be renewed in the ordinary course; and the Company is are in compliance in all material respects with all applicable federal, state, local and foreign laws, regulations, orders and decrees.

            (xiii) The Company has good and marketable title to all property (whether real or personal) described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus as being owned by it, in each case free and clear of all liens, claims, security interests, other encumbrances or defects except such as are disclosed in the Registration Statement the Time of Sale Disclosure Package and the Prospectus. The property held under lease by the Company is held by it under valid, subsisting and enforceable leases with only such exceptions with respect to any particular lease as do not interfere in any material respect with the conduct of the business of the Company.

            (xiv) Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company owns, possesses or can acquire on reasonable terms all Intellectual Property (as defined below) necessary for the conduct of the business of the Company as now conducted or as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus to be conducted, except to the extent such failure to own, possess or acquire such Intellectual Property would not result in a Material Adverse Change. Except as

disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus under the caption “Business-Patents and Proprietary Rights,” (i) to the knowledge of the Company, there is no infringement, misappropriation or violation by third parties of any such Intellectual Property; (ii) there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others challenging the rights of the Company in or to any such Intellectual Property, and the Company is unaware of any facts which would support any such claim; (iii) the Intellectual Property owned by the Company and, to the knowledge of the Company, the Intellectual Property licensed to the Company have not been adjudged invalid or unenforceable, in whole or in part, and there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others challenging the validity or scope of any such Intellectual Property, and the Company is unaware of any facts which would support any such claim; (iv) there is no pending or, to the knowledge of the Company, threatened action, suit, proceeding or claim by others that the Company infringes, misappropriates or otherwise violates any Intellectual Property or other proprietary rights of others, the Company has not received any written notice of such claim and the Company has no reason to believe that the conduct of its business conflicts with any such Intellectual Property or proprietary rights of others; and (v) to the Company’s knowledge, no employee of the Company is in or has ever been in violation of any material term of any employment contract, patent disclosure agreement, invention assignment agreement, non-competition agreement, non-solicitation agreement, nondisclosure agreement or any restrictive covenant to or with a former employer where the basis of such violation relates to such employee’s employment with the Company, or actions undertaken by the employee while employed with the Company. The term “Intellectual Property” as used herein means patents, patent applications, trade and service marks, trade and service mark registrations, trade names, copyrights, licenses, inventions, trade secrets, technology, know-how and other intellectual property.

            (xv) The Company is not (a) in violation of its charter or by-laws; (b) in breach of or otherwise in default, and no event has occurred which, with notice or lapse of time or both, would constitute such a default in the performance or observance of any material term, covenant, obligation, agreement or condition contained in any bond, debenture, note, indenture, loan agreement, mortgage, deed of trust, or any other material contract, lease or other instrument to which it is subject or by which it may be bound, or to which any of the material property or assets of the Company is subject or (c) in violation in any material respect of any law or statute or any order, rule, regulation, judgment or decree of any court or Governmental Authority.

            (xvi) The Company has timely filed all federal, state, local and foreign income and franchise tax returns required to be filed and are not in default in the payment of any material taxes which were payable pursuant to said returns or any assessments with respect thereto, other than any which the Company is contesting in good faith. There is no pending dispute with any taxing authority relating to any of such returns and the Company has no knowledge of any proposed liability for any tax

to be imposed upon the properties or assets of the Company for which there is not an adequate reserve reflected in the Company’s financial statements included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus

            (xvii) The Company has not distributed and will not distribute any prospectus or other offering material in connection with the offering and sale of the Securities other than any Preliminary Prospectus, the Time of Sale Disclosure Package or the Prospectus or other materials permitted by the Act to be distributed by the Company; provided, however, that, except as set forth on Schedule II, the Company has not made and will not make any offer relating to the Securities that would constitute a “free writing prospectus” as defined in Rule 405 except in accordance with the provisions of Section 4(s) of this Agreement.

            (xviii) The Securities have been approved for quotation on the Nasdaq National Market upon official notice of issuance and, on the date the Registration Statement became or becomes effective, the Company’s Registration Statement on Form 8-A or other applicable form under the Securities Exchange Act of 1934, as amended (the “Exchange Act”), became or will become effective.

            (xix) The Company has no subsidiaries. The Company, directly or indirectly, owns no capital stock or other equity or ownership or proprietary interest in any corporation, partnership, association, trust or other entity.

            (xx) The Company maintains a system of internal accounting controls sufficient to provide reasonable assurances that (i) transactions are executed in accordance with management’s general or specific authorization; (ii) transactions are recorded as necessary to permit preparation of financial statements in conformity with generally accepted accounting principles in the United States and to maintain accountability for assets; (iii) access to assets is permitted only in accordance with management’s general or specific authorization; and (iv) the recorded accountability for assets is compared with existing assets at reasonable intervals and appropriate action is taken with respect to any differences. Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, since the date of the most recent evaluation of such system of internal accounting controls, there has been no material change in internal control over financial reporting, including any corrective actions with regard to significant deficiencies or material weaknesses.

            (xxi) The Company’s board of directors has validly appointed an audit committee that satisfies the applicable requirements of Rule 4350(d)(2) of the Rules of the National Association of Securities Dealers, Inc. (the “NASD Rules”) and the Company’s board of directors and/or the audit committee has adopted a charter that satisfies the requirements of Rule 4350(d)(1) of the NASD Rules. Neither the Company’s board of directors nor the audit committee has been informed, nor is any director of the Company aware, of (1) any significant deficiency in the design or operation of the Company’s internal controls which could adversely affect the

Company’s ability to record, process, summarize and report financial data or any material weakness in the Company’s internal controls; or (2) any fraud, whether or not material, that involves management or other employees of the Company who have a significant role in the Company’s internal controls.

            (xxii) No relationship, direct or indirect, exists between or among the Company on the one hand, and the directors, officers, stockholders, customers or suppliers of the Company on the other hand, which is required to be described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus which is not so described. The Company has not, directly or indirectly, extended or maintained credit, or arranged for the extension of credit, or renewed an extension of credit, in the form of a personal loan to or for any of their directors or executive officers in violation of applicable laws, including Section 402 of the Sarbanes-Oxley Act.

            (xxiii) Except as described in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus: (i) the Company is and at all times has been in compliance in all material respects with all statutes, rules, regulations or guidances applicable to the ownership, testing, development, manufacture, packaging, processing, use, distribution, marketing, labeling, promotion, sale, offer for sale, storage, import, export or disposal of any product manufactured or distributed by the Company (“Applicable Laws”); (ii) the Company has not received any FDA Form 483, warning letter, untitled letter or other correspondence or notice from the U.S. Food and Drug Administration (“FDA”) or any other Governmental Authority alleging or asserting noncompliance with any Applicable Laws or any licenses, certificates, approvals, clearances, authorizations, permits and supplements or amendments thereto required by any such Applicable Laws (“Authorizations”); (iii) the Company possesses all material Authorizations and such material Authorizations are valid and in full force and effect and are not in violation of any term of any such material Authorizations; (iv) the Company has not received notice of any pending or threatened claim, action, suit, proceeding, hearing, enforcement, investigation, arbitration or other action from any Governmental Authority or third party alleging that any product, operation or activity is in violation of any Applicable Laws or Authorizations and the Company does not have knowledge that any such Governmental Authority or third party is considering any such claim, litigation, arbitration, action, suit, investigation or proceeding; (v) the Company has not received notice that any Governmental Authority has taken, is taking or intends to take action to limit, suspend, modify or revoke any Authorizations and the Company does not have knowledge that any such Governmental Authority is considering such action; (vi) the Company has filed, obtained, maintained or submitted all material reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments as required by any Applicable Laws or Authorizations and that all such reports, documents, forms, notices, applications, records, claims, submissions and supplements or amendments were complete and correct in all material respects on the date filed (or were corrected or supplemented in all material

respects by a subsequent submission); and (vii) the Company has not, either voluntarily or involuntarily, initiated, conducted or issued or caused to be initiated, conducted or issued, any recall, market withdrawal or replacement, safety alert, post sale warning, “dear doctor” letter or other notice or action relating to the alleged lack of safety or efficacy of any product or any alleged product defect or violation and, to the knowledge of the Company, no Governmental Authority has initiated, conducted or intends to initiate any such notice or action.

            (xxiv) The studies, tests and preclinical and clinical trials conducted by or, to the knowledge of the Company, on behalf of the Company were and, if still pending, are being conducted in accordance with experimental protocols, procedures and controls pursuant to accepted professional scientific standards and all Applicable Laws and Authorizations, including, without limitation, the Federal Food, Drug and Cosmetic Act and the rules and regulations promulgated thereunder at 21 C.F.R. Parts 50, 54, 56, 58 and 312 (collectively, “FFDCA”). The descriptions of the results of such studies, tests and trials contained in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus are accurate and complete in all material respects and fairly present the data derived from such studies, tests and trials. Except to the extent disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company does not have any knowledge of any studies, tests or trials the results of which reasonably call into question the study, test or trial results described or referred to in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus when viewed in the context in which such results are described and the clinical state of development. The Company has not received any notices or correspondence from any Governmental Authority requiring the termination, suspension or material modification of any studies, tests or preclinical or clinical trials conducted by or on behalf of the Company.

            (xxv) Without limiting the generality of clause (xxiv) above and except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company and its business operations are and at all times have been in compliance in all material respects with Health Care Laws. For purposes of this Agreement, “Health Care Laws” means (A) the federal Food, Drug and Cosmetic Act, and the regulations promulgated thereunder, (B) all federal and state fraud and abuse laws, including, without limitation, the federal Anti-Kickback Statute (42 U.S.C. §1320a-7b(b)), the Stark Law (42 U.S.C. §1395nn), the civil False Claims Act (31 U.S.C. §3729 et seq.), Sections 1320a-7 and 1320a-7a of Title 42 of the United States Code and the regulations promulgated pursuant to such statutes, (C) the Health Insurance Portability and Accountability Act of 1996 (18 U.S.C. §§669, 1035, 1347 and 1518; 42 U.S.C. §1320d et seq.) and the regulations promulgated thereunder, (D) the Controlled Substances Act (21 U.S.C. §801 et seq.), (E) Titles XVIII (42 U.S.C. §1395 et seq.) and XIX (42 U.S.C. §1396 et seq.) of the Social Security Act and the regulations promulgated thereunder, (F) the Medicare Prescription Drug, Improvement, and Modernization Act of 2003 (42 U.S.C. §1395w-101 et seq.) and the regulations promulgated thereunder, (G) quality, safety and

accreditation standards and requirements of all applicable state laws or regulatory bodies and (H) any and all other applicable health care laws, regulations, manual provisions, policies and administrative guidance, each of (A) through (H) as may be amended from time to time.

            (xxvi) The Company (i) is in compliance with any and all applicable federal, state, local and foreign laws, rules, regulations, decisions and orders relating to the protection of human health and safety, the environment or hazardous or toxic substances or wastes, pollutants or contaminants (collectively, “Environmental Laws”); (ii) has received and is in compliance with all permits, licenses or other approvals required of them under applicable Environmental Laws to conduct their business; and (iii) has not received notice of any actual or potential liability for the investigation or remediation of any disposal or release of hazardous or toxic substances or wastes, pollutants or contaminants, except in any such case for any such failure to comply, or failure to receive required permits, licenses or approvals, or liability as would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Change.

            (xxvii) Each employee benefit plan, within the meaning of Section 3(3) of the Employee Retirement Income Security Act of 1974, as amended (“ERISA”), that is maintained, administered or contributed to by the Company for employees or former employees of the Company has been maintained in compliance with its terms and the requirements of any applicable statutes, orders, rules and regulations, including ERISA and the Internal Revenue Code of 1986, as amended (the “Code”). No prohibited transaction, within the meaning of Section 406 of ERISA or Section 4975 of the Code, has occurred with respect to any such plan excluding transactions effected pursuant to a statutory or administrative exemption; and for each such plan that is subject to the funding rules of Section 412 of the Code or Section 302 of ERISA, no “accumulated funding deficiency” as defined in Section 412 of the Code has been incurred, whether or not waived, and the fair market value of the assets of each such plan (excluding for these purposes accrued but unpaid contributions) exceeds the present value of all benefits accrued under such plan determined using reasonable actuarial assumptions.

            (xxviii) Except as disclosed in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus, the Company has not granted rights to develop, manufacture, produce, assemble, distribute, license, market or sell its products to any other person and is not bound by any agreement that affects the exclusive right of the Company to develop, manufacture, produce, assemble, distribute, license, market or sell its products.

            (xxix) Nothing has come to the attention of the Company that has caused the Company to believe that the statistical and market-related data included in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus is

not based on or derived from sources that are reliable and accurate in all material respects.

            (xxx) Other than as contemplated by this Agreement, the Company has not incurred any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby.

            (xxxi) The Company is not presently doing business with the government of Cuba or with any person or affiliate located in Cuba.

            (xxxii) The Company carries, or is covered by, insurance in such amounts and covering such risks as is adequate for the conduct of its business and the value of its properties and as is customary for companies engaged in similar businesses in similar industries; and the Company has (i) not received notice from any insurer or agent of such insurer that capital improvements or other expenditures are required or necessary to be made in order to continue such insurance or (ii) no reason to believe that it will not be able to renew its existing insurance coverage as and when such coverage expires or to obtain similar coverage at reasonable cost from similar insurers as may be necessary to continue its business.

            (xxxiii) Neither the Company nor, to the knowledge of the Company, any director, officer, agent, employee or other person associated with or acting on behalf of the Company has (i) used any corporate funds for any unlawful contribution, gift, entertainment or other unlawful expense relating to political activity; (ii) made any direct or indirect unlawful payment to any foreign or domestic government official or employee from corporate funds; (iii) violated or is in violation of any provision of the Foreign Corrupt Practices Act of 1977; or (iv) made any bribe, rebate, payoff, influence payment, kickback or other unlawful payment.

            (xxxiv) Except with notice to the Representatives and compliance with applicable laws, none of the Directed Stock (as defined below) distributed in connection with the Directed Stock Program (as defined below) will be offered or sold outside of the United States.

            (xxxv) The Company is not and, after giving effect to the offering and sale of the Securities, will not be an “investment company,” as such term is defined in the Investment Company Act of 1940, as amended.

            (xxxvi) The Company is in compliance with all applicable provisions of the Sarbanes-Oxley Act and the rules and regulations of the Commission thereunder.

          (b) Any certificate signed by any executive officer of the Company and delivered to you or to counsel for the Underwriters in connection with the transactions contemplated by this Agreement shall be deemed a representation and warranty by the Company to each Underwriter as to the matters covered thereby.

     3. Purchase, Sale and Delivery of Securities.

          (a) On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company agrees to issue

and sell the Firm Shares to the several Underwriters, and each Underwriter agrees, severally and not jointly, to purchase from the Company the number of Firm Shares set forth opposite the name of such Underwriter in Schedule I hereto. The purchase price for each Firm Share shall be $        per share. In making this Agreement, each Underwriter is contracting severally and not jointly; except as provided in paragraph (c) of this Section 3 and in Section 8 hereof, the agreement of each Underwriter is to purchase only the respective number of Firm Shares specified in Schedule I.

          It is understood that ___shares of the Firm Shares (“Directed Stock”) will initially be reserved by the Underwriters for offer and sale to employees and persons having relationships with the Company or its employees (“Directed Stock Participants”) upon the terms and conditions set forth in the Registration Statement, the Time of Sale Disclosure Package and the Prospectus and in accordance with the rules and regulations of the National Association of Securities Dealers (“Directed Stock Program”). Under no circumstance will the Representatives or any Underwriter be liable to the Company or to any Directed Stock Participant for any action taken or omitted to be taken in good faith in connection with such Directed Stock Program. To the extent that any shares of Directed Stock are not affirmatively reconfirmed for purchase by any Directed Stock Participant on or immediately after the date of this Agreement, such Directed Stock may be offered to the public as part of the public offering contemplated hereby. The Company agrees to pay all fees and disbursements incurred by the Underwriters in connection with the Directed Stock Program, including counsel fees and any stamp duties or other taxes incurred by the Underwriters in connection with the Directed Stock Program.

          The Firm Shares will be delivered by the Company to you for the accounts of the several Underwriters against payment of the purchase price therefor by wire transfer of same day funds payable to the order of the Company at the offices of Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California 94025, or such other location as may be mutually acceptable, at 10:00 a.m. Eastern time on the third (or if the Securities are priced, as contemplated by Rule 15c6-1(c) under the Exchange Act, after 4:30 p.m. Eastern time, the fourth) full business day following the date hereof, or at such other time and date as you and the Company determine pursuant to Rule 15c6-1(a) under the Exchange Act, such time and date of delivery being herein referred to as the “First Closing Date.” If the Representatives so elect, delivery of the Firm Shares may be made by credit through full fast transfer to the accounts at The Depository Trust Company designated by the Representatives. Certificates representing the Firm Shares, in definitive form and in such denominations and registered in such names as you may request upon at least two business days’ prior notice to the Company, will be made available for checking and packaging not later than 10:00 a.m., Eastern time, on the business day next preceding the First Closing Date at the offices of Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California 94025, or such other location as may be mutually acceptable.

          (b) On the basis of the representations, warranties and agreements herein contained, but subject to the terms and conditions herein set forth, the Company hereby grants, to the several Underwriters an option to purchase all or any portion of the Option Shares at the same purchase price as the Firm Shares, for use solely in covering any over-allotments made by the Underwriters in the sale and distribution of the Firm Shares. The option granted hereunder may be exercised in whole or in part at any time (but not more than once) within 30 days after the effective date of this Agreement upon notice (confirmed in writing) by the Representatives to the Company setting forth the aggregate number of Option Shares as to which the several Underwriters are exercising the option, the names and denominations in which the certificates for the Option Shares are to be registered and the date and time, as determined by you, when the Option Shares are to be delivered, such time and date being herein referred to as the “Second Closing” and “Second Closing Date,” respectively; provided, however, that the Second Closing Date shall not be earlier than the First Closing Date nor earlier than the second business day after the date on which the option shall have been exercised. If the option is exercised, the number of Option Shares to be purchased by each Underwriter shall be the same percentage of the total number of Option Shares to be purchased by the several Underwriters as the number of Firm Shares to be purchased by such Underwriter is of the total number of Firm Shares to be purchased by the several Underwriters, as adjusted by the Representatives in such manner as the

     Representatives deem advisable to avoid fractional shares. No Option Shares shall be sold and delivered unless the Firm Shares previously have been, or simultaneously are, sold and delivered.

          The Option Shares will be delivered by the Company to you for the accounts of the several Underwriters against payment of the purchase price therefor by wire transfer of same day funds payable to the order of the Company, at the offices of Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California 94025, or such other location as may be mutually acceptable at 10:00 a.m., Eastern time, on the Second Closing Date. If the Representatives so elect, delivery of the Option Shares may be made by credit through full fast transfer to the accounts at The Depository Trust Company designated by the Representatives. Certificates representing the Option Shares in definitive form and in such denominations and registered in such names as you have set forth in your notice of option exercise, will be made available for checking and packaging not later than 10:00 a.m., Eastern time, on the business day next preceding the Second Closing Date at the offices of Latham & Watkins LLP, 135 Commonwealth Drive, Menlo Park, California 94025 or such other location as may be mutually acceptable.

          (c) It is understood that you, individually and not as Representatives of the several Underwriters, may (but shall not be obligated to) make payment to the Company on behalf of any Underwriter for the Securities to be purchased by such Underwriter. Any such payment by you shall not relieve any such Underwriter of any of its obligations hereunder. Nothing herein contained shall constitute any of the Underwriters an unincorporated association or partner with the Company.

     4. Covenants.

     The Company covenants and agrees with the several Underwriters as follows:

          (a) If the Registration Statement has not already been declared effective by the Commission, the Company will use its best efforts to cause the Registration Statement and any post-effective amendments thereto to become effective as promptly as possible; the Company will notify you promptly of the time when the Registration Statement or any post-effective amendment to the Registration Statement has become effective or any supplement to the Prospectus has been filed and of any request by the Commission for any amendment or supplement to the Registration Statement or Prospectus or additional information; if the Company has elected to rely on Rule 430A, the Company will prepare and file a Prospectus containing the information omitted therefrom pursuant to Rule 430A with the Commission within the time period required by, and otherwise in accordance with the provisions of, Rules 424(b) and 430A; if the Company has elected to rely upon Rule 462(b) to increase the size of the offering registered under the Act, the Company will prepare and file a registration statement with respect to such increase with the Commission within the time period required by, and otherwise in accordance with the provisions of, Rule 462(b); the Company will prepare and file with the Commission, promptly upon your request, any amendments or supplements to the Registration Statement or Prospectus that, in your

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opinion, may be necessary or advisable in connection with the distribution of the Securities by the Underwriters; and the Company will not file any amendment or supplement to the Registration Statement or Prospectus to which you shall reasonably object by notice to the Company after having been furnished a copy a reasonable time prior to the filing.

          (b) The Company will advise you, promptly after it shall receive notice or obtain knowledge thereof, of the issuance by the Commission of any stop order suspending the effectiveness of the Registration Statement, or any post-effective amendment thereto, or preventing or suspending the use of any Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus or any Issuer-Represented Free Writing Prospectus, of the suspension of the qualification of the Securities for offering or sale in any jurisdiction, or of the initiation or threatening of any proceeding for any such purpose; and the Company will promptly use its best efforts to prevent the issuance of any stop order or to obtain its withdrawal if such a stop order should be issued. Additionally, the Company agrees that it shall comply with the provisions of Rules 424(b) and 430A, as applicable, and will use its reasonable efforts to confirm that any filings made by the Company under Rule 424(b), Rule 433 or Rule 462 were received in a timely manner by the Commission.

          (c) (i) Within the time during which a prospectus (or in lieu thereof the notice referred to in Rule 173(a) of the Rules and Regulations (“Rule 173”) relating to the Securities is required to be delivered under the Act (the “Prospectus Delivery Period”) the Company will comply as far as it is able with all requirements imposed upon it by the Act, as now and hereafter amended, and by the Rules and Regulations, as from time to time in force, so far as necessary to permit the continuance of sales of or dealings in the Securities as contemplated by the provisions hereof, the Time of Sale Disclosure Package and the Prospectus. If during the Prospectus Delivery Period (A) any event shall occur or condition shall exist as a result of which the Prospectus, as then amended or supplemented (or if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) would include an untrue statement of a material fact or omit to state a material fact necessary to make the statements therein, in the light of the circumstances then existing, not misleading, or (B) it is necessary to amend the Registration Statement or supplement the Prospectus (or if the Prospectus is not yet available to prospective investors, the Time of Sale Disclosure Package) to comply with the Act, the Company will promptly notify you and will amend the Registration Statement or supplement the Prospectus (or, if the Prospectus is not yet available to prospective purchasers, the Time of Sale Disclosure Package) (at the expense of the Company) so as to correct such statement or omission or effect such compliance.

               (ii) If at any time following issuance of an Issuer-Represented General Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer-Represented General Free Writing Prospectus, conflicted or would conflict with the information contained in the Registration Statement relating to the Securities or included or would include an untrue statement of a material fact or omitted or would omit to state a material fact necessary in order to make the statements therein, in the light of the circumstances prevailing at that subsequent time, not misleading, the Company has promptly notified or promptly will notify the Representatives and has promptly amended or will promptly amend or supplement, at its own expense, such Issuer-Represented General Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission.

          (d) The Company shall take or cause to be taken all necessary action to qualify the Securities for sale under the securities laws of such jurisdictions as you reasonably designate and to continue such qualifications in effect so long as required for the distribution of the Securities, except that the Company shall not be required in connection therewith to qualify as a foreign corporation or to execute a general consent to service of process in any state.

          (e) The Company will furnish to the Underwriters and counsel for the Underwriters copies of the Registration Statement (three of which will be signed and will include all consents and exhibits filed therewith), each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus and all amendments and supplements to such documents, in each case as soon as available and in such quantities as you may from time to time reasonably request.

          (f) During a period of five years commencing with the date hereof, the Company will furnish to the Representatives, and to each Underwriter who may so request in writing, copies of all periodic and special reports furnished to the stockholders of the Company and all information, documents and reports filed with the Commission, the National Association of Securities Dealers, Inc., Nasdaq or any securities exchange (other than any such information, documents and reports that are filed with the Commission electronically via EDGAR or any successor system).

          (g) The Company will make generally available to its security holders as soon as practicable, but in any event not later than 15 months after the end of the Company’s current fiscal quarter, an earnings statement (which need not be audited) covering a 12-month period beginning after the effective date of the Registration Statement that shall satisfy the provisions of Section 11(a) of the Act and Rule 158 of the Rules and Regulations.

          (h) The Company, whether or not the transactions contemplated hereunder are consummated or this Agreement is prevented from becoming effective under the provisions of Section 9(a) hereof or is terminated, will pay or cause to be paid (i) all expenses (including transfer taxes allocated to the respective transferees) incurred in connection with the delivery to the Underwriters of the Securities, (ii) all expenses and fees (including, without limitation, fees and expenses of the Company’s accountants and counsel but, except as otherwise provided

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below, not including fees of the Underwriters’ counsel) in connection with the preparation, printing, filing, delivery, and shipping of the Registration Statement (including the financial statements therein and all amendments, schedules, and exhibits thereto), the Securities, each Preliminary Prospectus, the Time of Sale Disclosure Package, the Prospectus, and any amendment thereof or supplement thereto, and any Issuer-Represented Free Writing Prospectus and the printing, delivery, and shipping of this Agreement and other underwriting documents, including Blue Sky Memoranda (covering the states and other applicable jurisdictions), (iii) all filing fees and fees and disbursements (not in excess, in the aggregate, of $10,000) of the Underwriters’ counsel incurred in connection with the qualification of the Securities for offering and sale by the Underwriters or by dealers under the securities or blue sky laws of the states and other jurisdictions which you shall designate or are necessary to distribute the Directed Stock, (iv) the fees and expenses of any transfer agent or registrar, (v) the filing fees incident to any required review by the National Association of Securities Dealers, Inc. of the terms of the sale of the Securities, (vi) listing fees, if any, (vii) the costs and expenses relating to investor presentations on any “road show” undertaken in connection with the marketing of the Securities and (viii) all other costs and expenses incident to the performance of its obligations hereunder that are not otherwise specifically provided for herein; provided, however, that the Underwriters shall bear the cost of travel and lodging for the Underwriters in connection with the investor presentations on any “road show” undertaken in connection with the marketing of the Securities; provided, however, that travel and lodging costs not attributable solely to the Underwriters (i.e., shared travel costs such as a chartered aircraft) shall be shared equally by the Company and the Underwriters. If the sale of the Securities provided for herein is not consummated by reason of action by the Company pursuant to Section 9(a) hereof or action by you pursuant to Section 9(b) hereof which prevents this Agreement from becoming effective, or by reason of any failure, refusal or inability on the part of the Company to perform any agreement on its part to be performed, or because any other condition of the Underwriters’ obligations hereunder required to be fulfilled by the Company is not fulfilled, the Company will reimburse the several Underwriters for all out-of-pocket disbursements (including reasonable fees and disbursements of counsel) incurred by the Underwriters in connection with their investigation, preparing to market and marketing the Securities or in contemplation of performing their obligations hereunder. The Company shall not in any event be liable to any of the Underwriters for loss of anticipated profits from the transactions covered by this Agreement.

          (i) The Company will apply the net proceeds from the sale of the Securities to be sold by it hereunder for the purposes set forth in the Prospectus and will file such reports with the Commission with respect to the sale of the Securities and the application of the proceeds therefrom as may be required in accordance with Rule 463 of the Rules and Regulations.

          (j) The Company will not, without the prior written consent of Piper Jaffray & Co., and Pacific Growth Equities, LLC from the date of execution of this Agreement and continuing to and including the date 180 days after the date of the Prospectus (the “Lock-Up Period”) offer for sale; sell, contract to sell, pledge, grant any option for the sale of, enter into any transaction which is designed to, or might reasonably be expected to, result in the disposition (whether by actual disposition or effective economic disposition due

to cash settlement or otherwise) by the Company or any affiliate, or otherwise issue or dispose of, directly or indirectly (or publicly disclose the intention to make any such offer, sale, pledge, grant, issuance or other disposition), any Common Stock or any securities convertible into or exchangeable for, or any options or rights to purchase or acquire, Common Stock, except (i) to the Underwriters pursuant to this Agreement, (ii) to directors, employees and consultants of the Company pursuant to the Company’s 2001 Equity Incentive Plan, 2002 Equity Incentive Plan, as amended, 2005 Equity Incentive Plan, 2005 Employee Stock Purchase Plan and 2005 Non-Employee Directors’ Stock Option Plan and (iii) upon exercise or conversion of securities outstanding as of the date hereof. Notwithstanding the foregoing, for the purpose of allowing the Underwriters to comply with NASD Rule 2711(f)(4), if (i) during the last 17 days of the Lock-Up Period, the Company releases earnings results or publicly announces other material news or a material event relating to the Company is publicly announced or occurs or (ii) prior to the expiration of the Lock-Up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the Lock-Up Period, then in each case the Lock-Up Period will be extended until the expiration of the 18-day period beginning on the date of release of the earnings results or the public announcement regarding the material news or the occurrence of the material event, as applicable, unless Piper Jaffray & Co. and Pacific Growth Equities, LLC waive, in writing, such extension; provided, however, that this provision will not apply to any research report concerning the Company to be published or distributed by an Underwriter pursuant to Rule 139 promulgated under the Securities Act at a time when the Company’s shares of Common Stock are “actively traded securities,” as defined in Regulation M, 17 C.F.R. 242.101(c)(1). The Company agrees not to accelerate the vesting of any option or warrant or the lapse of any repurchase right prior to the expiration of the Lock-Up Period, unless all securities of the Company owned by such person are subject to the restrictions set forth in this paragraph (j).

          (k) The Company either has caused to be delivered to you or will cause to be delivered to you prior to the effective date of the Registration Statement an agreement substantially in the form attached hereto as Exhibit A from each of the Company’s directors, officers, stockholders, warrantholders and optionholders (the “Lock-Up Agreement”). The Company will enforce the terms of each Lock-Up Agreement and issue stop-transfer instructions to the transfer agent for the Common Stock with respect to any transaction or contemplated transaction that would constitute a breach of or default under the applicable Lock-Up Agreement.

          (l) The Company has not taken and will not take, directly or indirectly, any action designed to or which might reasonably be expected to cause or result in, or which has constituted, the stabilization or manipulation of the price of any security of the Company to facilitate the sale or resale of the Securities, and has not effected any sales of Common Stock which are required to be disclosed in response to Item 701 of Regulation S-K under the Act which have not been so disclosed in the Registration Statement.

          (m) The Company will not incur any liability for any finder’s or broker’s fee or agent’s commission in connection with the execution and delivery of this Agreement or the consummation of the transactions contemplated hereby.

          (n) The Company will comply with all applicable securities and other applicable laws, rules and regulations in each foreign jurisdiction in which Directed Stock is offered in connection with the Directed Stock Program.

          (o) In connection with the Directed Stock Program to ensure that the Directed Stock will be restricted to the extent required by the National Association of Securities Dealers or the rules of such association from sale, transfer, assignment, pledge or hypothecation for a period of three months following the date of the effectiveness of the Registration Statement, the Company will direct the transfer agent to place stop-transfer restrictions upon such securities for such period of time. Should the Company release, or seek to release, from such restrictions any of the Directed Stock, the Company agrees to reimburse the Underwriters for any reasonable expense (including, without limitation, legal expenses) they incur with such release.

          (p) The Company will file with the Commission such periodic and special reports as required by the Rules and Regulations.

          (q) The Company will maintain such controls and other procedures required by Sections 302 and 906 of the Sarbanes-Oxley Act and the applicable regulations thereunder that are designed to ensure that information required to be disclosed by the Company in the reports that 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, including without limitation, controls and procedures designed to ensure that information required to be disclosed by the Company in the reports that it files or submits under the Exchange Act is accumulated and communicated to the Company’s management, including its principal executive officer and its principal financial officer, or persons performing similar functions, as appropriate to allow timely decisions regarding required disclosure, to ensure that material information relating to Company is made known to them by others within those entities.

          (r) The Company will comply with all effective applicable provisions of the Sarbanes-Oxley Act.

          (s) The Company represents and agrees that, unless it obtains the prior written consent of Piper Jaffray & Co. and Pacific Growth Equities, LLC, and each Underwriter severally represents and agrees that, unless it obtains the prior consent of the Company, Piper Jaffray & Co. and Pacific Growth Equities, LLC, it has not made and will not make any offer relating to the Securities that would constitute an “issuer free writing prospectus,” as defined in Rule 433, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405, required to be filed with the Commission. Any such free writing prospectus consented to by the Company, Piper Jaffray & Co. and Pacific Growth Equities, LLC is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated or agrees that it will treat each Permitted Free Writing Prospectus as an “issuer free writing prospectus,” as defined in Rule 433, and has complied and will comply with the requirements of Rule 433 applicable to any Permitted Free Writing Prospectus, including timely Commission filing where required, legending and record keeping. The Company represents that it has satisfied and agrees that it will satisfy the conditions in Rule 433 to avoid a requirement to file with the Commission any electronic road show.

     5. Conditions of Underwriters’ Obligations. The obligations of the several Underwriters hereunder are subject to the accuracy, as of the date hereof and at each of the First Closing Date and the Second Closing Date (as if made at such Closing Date), of and compliance with all representations, warranties and agreements of the Company contained

herein, to the performance by the Company of its obligations hereunder and to the following additional conditions:

          (a) The Registration Statement shall have become effective not later than 6:00 p.m., Eastern time, on the date of this Agreement, or such later time and date as you, as Representatives of the several Underwriters, shall approve and all filings required by Rules 424, 430A and 433 shall have been timely made; no stop order suspending the effectiveness of the Registration Statement or any amendment thereof shall have been issued; no proceedings for the issuance of such an order shall have been initiated or threatened; and any request of the Commission for additional information (to be included in the Registration Statement, the Time of Sale Disclosure Package, the Prospectus, any Issuer-Represented Free Writing Prospectus or otherwise) shall have been complied with to your satisfaction.

          (b) No Underwriter shall have advised the Company that the Registration Statement, the Time of Sale Disclosure Package or the Prospectus, or any amendment thereof or supplement thereto, or any Issuer-Represented Free Writing Prospectus contains an untrue statement of fact which, in your opinion, is material, or omits to state a fact which, in your opinion, is material and is required to be stated therein or necessary to make the statements therein, in light of the circumstances under which they are made, not misleading.

          (c) Except as contemplated in the Time of Sale Disclosure Package and the Prospectus, subsequent to the respective dates as of which information is given in the Time of Sale Disclosure Package, the Company shall not have incurred any material liabilities or obligations, direct or contingent, or entered into any material transactions, or declared or paid any dividends or made any distribution of any kind with respect to its capital stock; and there shall not have been any change in the capital stock (other than a change in the number of outstanding shares of Common Stock due to the issuance of shares upon the exercise of outstanding options or warrants), or any material change in the short-term or long-term debt of the Company, or any issuance of options, warrants, convertible securities or other rights to purchase the capital stock of the Company, or any Material Adverse Change or any development involving a prospective Material Adverse Change (whether or not arising in the ordinary course of business), that, in your judgment, makes it impractical or inadvisable to offer or deliver the Securities on the terms and in the manner contemplated in the Time of Sale Disclosure Package and the Prospectus.

          (d) On each Closing Date, there shall have been furnished to you, as Representatives of the several Underwriters, the opinion of Cooley Godward LLP, counsel for the Company, dated such Closing Date and addressed to you, in the form set forth on Exhibit B.

          In rendering such opinion such counsel may rely (i) as to matters of law other than California and federal law, upon the opinion or opinions of local counsel provided that the extent of such reliance is specified in such opinion and that such counsel shall state that such opinion or opinions of local counsel are satisfactory to them and that they believe they and you are justified in relying thereon and (ii) as to matters of fact, to the extent such counsel deems