Shares

EXHIBIT 1.1

                 Shares

NOVACEA, INC.

Common Stock, par value $0.001 per share

UNDERWRITING AGREEMENT

                    , 2006

BEAR, STEARNS & CO. INC.

COWEN & CO., LLC

PACIFIC GROWTH EQUITIES, LLC

HSBC SECURITIES (USA)

As Representatives of the Several Underwriters,

Dear Sirs:

1. Introductory. Novacea, Inc., a Delaware corporation (“Company”), proposes to issue and sell                  shares (“Firm Securities”) of its common stock, par value $0.001 per share (“Securities”) and also proposes to issue and sell to the Underwriters, at the option of the Underwriters, an aggregate of not more than                  additional shares (“Optional Securities”) of its Securities as set forth below. The Firm Securities and the Optional Securities are herein collectively called the “Offered Securities”. The Company hereby agrees with the several Underwriters named in Schedule A hereto (“Underwriters”) as follows:

2. Representations and Warranties of the Company. The Company represents and warrants to, and agrees with, the several Underwriters that:

(a) A registration statement (No. 333-131741) relating to the Offered Securities, including a form of prospectus, has been filed with the Securities and Exchange Commission (“Commission”) and either (i) has been declared effective under the Securities Act of 1933 (“Act”) and is not proposed to be amended or (ii) is proposed to be amended by amendment or post-effective amendment. If such registration statement (“initial registration statement”) has been declared effective, either (i) an additional registration statement (“additional registration statement”) relating to the Offered Securities may have been filed with the Commission pursuant to Rule 462(b) (“Rule 462(b)”) under the Act and, if so filed, has become effective upon filing pursuant to such Rule and the Offered Securities all have been duly registered under the Act pursuant to the initial registration statement and, if applicable, the additional registration statement or (ii) such an additional registration statement is proposed to be filed with the Commission pursuant to Rule 462(b) and will become effective upon filing pursuant to such Rule and upon such filing the Offered Securities will all have been duly registered under the Act pursuant to the initial

registration statement and such additional registration statement. If the Company does not propose to amend the initial registration statement or if an additional registration statement has been filed and the Company does not propose to amend it, and if any post-effective amendment to either such registration statement has been filed with the Commission prior to the execution and delivery of this Agreement, the most recent amendment (if any) to each such registration statement has been declared effective by the Commission or has become effective upon filing pursuant to Rule 462(c) (“Rule 462(c)”) under the Act or, in the case of the additional registration statement, Rule 462(b). For purposes of this Agreement, “Effective Time” with respect to the initial registration statement or, if filed prior to the execution and delivery of this Agreement, the additional registration statement means (i) if the Company has advised the Representatives that it does not propose to amend such registration statement, the date and time as of which such registration statement, or the most recent post-effective amendment thereto (if any) filed prior to the execution and delivery of this Agreement, was declared effective by the Commission or has become effective upon filing pursuant to Rule 462(c), or (ii) if the Company has advised the Representatives that it proposes to file an amendment or post-effective amendment to such registration statement, the date and time as of which such registration statement, as amended by such amendment or post-effective amendment, as the case may be, is declared effective by the Commission. If an additional registration statement has not been filed prior to the execution and delivery of this Agreement but the Company has advised the Representatives that it proposes to file one, “Effective Time” with respect to such additional registration statement means the date and time as of which such registration statement is filed and becomes effective pursuant to Rule 462(b). “Effective Date” with respect to the initial registration statement or the additional registration statement (if any) means the date of the Effective Time thereof. The initial registration statement, as amended at its Effective Time, including all information contained in the additional registration statement (if any) and deemed to be a part of the initial registration statement as of the Effective Time of the additional registration statement pursuant to the General Instructions of the Form on which it is filed and including all information (if any) deemed to be a part of the initial registration statement as of its Effective Time pursuant to Rule 430A(b) (“Rule 430A(b)”) under the Act, is hereinafter referred to as the “Initial Registration Statement”. The additional registration statement (if any), as amended at its Effective Time, including the contents of the initial registration statement incorporated by reference therein and including all information (if any) deemed to be a part of the additional registration statement as of its Effective Time pursuant to Rule 430A(b), is hereinafter referred to as the “Additional Registration Statement”. The Initial Registration Statement and the Additional Registration Statement are herein referred to collectively as the “Registration Statements” and individually as a “Registration Statement”. “Registration Statement”, without reference to a time, means the Registration Statement as of its Effective Time. “Registration Statement” as of any time means the initial registration statement and any additional registration statement in the form then filed with the Commission, including any amendment thereto and any prospectus deemed or retroactively deemed to be a part thereof that has not been superseded or modified. For purposes of the previous sentence, information contained in a form of prospectus or prospectus supplement that is deemed retroactively to be a part of the Registration Statement pursuant to Rule 430A shall be considered to be included in the Registration Statement as of the time specified in Rule 430A. “Statutory Prospectus” as of any time means the prospectus included in the Registration Statement immediately prior to that time, including any prospectus deemed to be a part thereof that has not been superseded or modified. For purposes of the preceding sentence, 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) (“Rule 424(b)”) under the Act. “Prospectus” means the Statutory Prospectus that discloses the public offering price and other final terms of the Offered Securities and otherwise satisfies Section 10(a) of the Act. “Issuer Free Writing Prospectus” means any “issuer free writing prospectus,” as defined in Rule 433(h)(1) and relating to the Offered Securities 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

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433(g). “General Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is intended for general distribution to prospective investors, as evidenced by its being specified in Appendix I to this Agreement. “Limited Use Issuer Free Writing Prospectus” means any Issuer Free Writing Prospectus that is not a General Use Issuer Free Writing Prospectus. “Applicable Time” means                  (Eastern time) on the date of this Agreement.

(b) If the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement: (i) on the Effective Date of the Initial Registration Statement, the Initial Registration Statement conformed in all respects to the requirements of the Act and the rules and regulations of the Commission thereunder (“Rules and Regulations”) and did not include any untrue statement of a material fact or omit to state any material fact required to be stated therein or necessary to make the statements therein (in the case of the Statutory Prospectus, in light of the circumstances under which they were made) not misleading, (ii) on the Effective Date of the Additional Registration Statement (if any), each Registration Statement conformed, or will conform, in all respects to the requirements of the Act and the Rules and Regulations and did not include, or will not include, any untrue statement of a material fact and did not omit, or will not omit, to state any material fact required to be stated therein or necessary to make the statements therein (in the case of the Statutory Prospectus, in light of the circumstances under which they were made) not misleading and (iii) on the date of this Agreement, the Initial Registration Statement and, if the Effective Time of the Additional Registration Statement (if any) is prior to the execution and delivery of this Agreement, the Additional Registration Statement each conforms, and at the time of filing of the Prospectus pursuant to Rule 424(b) or (if no such filing is required) at the Effective Date of the Additional Registration Statement in which the Prospectus is included, each Registration Statement and the Prospectus will conform, in all respects to the requirements of the Act and the Rules and Regulations, and neither of such documents includes, or will include, any untrue statement of a material fact or omits, or will omit, to state any material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in light of the circumstances under which they were made) not misleading. If the Effective Time of the Initial Registration Statement is subsequent to the execution and delivery of this Agreement: on the Effective Date of the Initial Registration Statement, the Initial Registration Statement and the Prospectus will conform in all respects to the requirements of the Act and the Rules and Regulations, neither of such documents will include any untrue statement of a material fact or will omit to state any material fact required to be stated therein or necessary to make the statements therein (in the case of the Prospectus, in light of the circumstances under which they were made) not misleading, and no Additional Registration Statement has been or will be filed. The two preceding sentences do not apply to statements in or omissions from a Registration Statement or the Prospectus based upon written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information is that described as such in Section 8(b) hereof.

(c) (i) At the time of the initial filing of the initial registration statement and (ii) at the date of this Agreement, the Company was not and is not an “ineligible issuer,” as defined in Rule 405, and (x) the Company or any other subsidiary in the preceding three years has not been convicted of a felony or misdemeanor or been made the subject of a judicial or administrative decree or order arising out of a government action as described in Rule 405 and (y) the Company in the preceding three years has not been the subject of a bankruptcy petition or insolvency or similar proceeding, has not had a registration statement be the subject of a proceeding under Section 8 of the Act and has not been the subject of a proceeding under Section 8A of the Act in connection with the offering of the Offered Securities, all as described in Rule 405.

(d) As of the Applicable Time, neither (i) the General Use Issuer Free Writing Prospectus(es) issued at or prior to the Applicable Time (if any), the preliminary prospectus, dated [            ], 2006 (which is the most recent Statutory Prospectus distributed generally to prospective investors), and

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the information set forth on Schedule B, all considered together (collectively, the “General Disclosure Package”), nor (ii) any individual Limited Use Issuer Free Writing Prospectus (if any), when considered together with the General Disclosure Package, included any untrue statement of a material fact or omitted 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 prospectus included in the Registration Statement or any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8(b) hereof.

(e) Each Issuer Free Writing Prospectus (if any) that has not been superseded or modified by an amendment to the Registration Statement filed prior to the time of the execution of this Agreement, as of its issue date and as of the Closing Date or until any earlier date that the Company notified or notifies Bear Stearns & Co. Inc. (“Bear Stearns”) and Cowen & Co., LLC (“Cowen & Co.”) as described in the next sentence, did not, does not and will not include any information that conflicted, conflicts or will conflict with the information then contained in the Registration Statement. If at any time following issuance of an Issuer Free Writing Prospectus there occurred or occurs an event or development as a result of which such Issuer Free Writing Prospectus conflicted or would conflict with the information then contained in the Registration Statement 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, (i) the Company has promptly notified or will promptly notify Bear Stearns and Cowen & Co. and (ii) the Company has promptly amended or will promptly amend or supplement such Issuer Free Writing Prospectus to eliminate or correct such conflict, untrue statement or omission. The foregoing two sentences do not apply to statements in or omissions from any Issuer Free Writing Prospectus in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in Section 8(b) hereof.

(f) The Company has been duly incorporated and is an existing corporation in good standing under the laws of the State of Delaware, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification except where the failure to so qualify or be in good standing would not reasonably be expected to, individually or in the aggregate, have a material adverse effect on the condition (financial or otherwise), business, properties or results of operations of the Company and its subsidiaries taken as a whole (“Material Adverse Effect”).

(g) The Company has no significant subsidiaries (as such term is defined in Rule 1-02 of Regulation S-X promulgated under the Act). Each subsidiary of the Company has been duly incorporated and is an existing corporation in good standing under the laws of the jurisdiction of its incorporation, with power and authority (corporate and other) to own its properties and conduct its business as described in the General Disclosure Package; and each subsidiary of the Company is duly qualified to do business as a foreign corporation in good standing in all other jurisdictions in which its ownership or lease of property or the conduct of its business requires such qualification except where the failure to so qualify or be in good standing would not, individually or in the aggregate, reasonably be expected to have a Material Adverse Effect; all of the issued and outstanding capital stock of each subsidiary of the Company has been duly authorized and validly

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issued and is fully paid and nonassessable; and the capital stock of each subsidiary owned by the Company, directly or through subsidiaries, is owned free from liens, encumbrances and defects.

(h) The Offered Securities and all other outstanding shares of capital stock of the Company have been duly authorized; all outstanding shares of capital stock of the Company are, and, when the Offered Securities have been delivered and paid for in accordance with this Agreement on each Closing Date (as defined below), such Offered Securities will have been, validly issued, fully paid and nonassessable and will conform to the description thereof contained in the General Disclosure Package; and the stockholders of the Company have no preemptive rights with respect to the Securities.

(i) Except as disclosed in the General Disclosure Package, there are no contracts, agreements or understandings between the Company and any person that would give rise to a valid claim against the Company or any Underwriter for a brokerage commission, finder’s fee or other like payment in connection with this offering.

(j) Except as disclosed in the General Disclosure Package, there are no contracts, agreements or understandings between the Company and any person granting such person the right to require the Company to file a registration statement under the Act with respect to any securities of the Company owned or to be owned by such person or to require the Company to include such securities in the securities registered pursuant to a Registration Statement or in any securities being registered pursuant to any other registration statement filed by the Company under the Act.

(k) The Offered Securities have been approved for listing on the Nasdaq Stock Market’s National Market subject to notice of issuance.

(l) No consent, approval, authorization, or order of, or filing with, any governmental agency, body or any court is required for the consummation of the transactions contemplated by this Agreement in connection with the issuance and sale of the Offered Securities by the Company, except (i) such as have been obtained and made (ii) such as may be required under state securities laws or (iii) such as may be required under the rules and regulations of the National Association of Securities Dealers, Inc. (the “NASD”).

(m) The execution, delivery and performance of this Agreement, and the issuance and sale of the Offered Securities will not result in a breach or violation of any of the terms and provisions of, or constitute a default under, (i) any statute, any rule, regulation or order of any governmental agency, body or any court, domestic or foreign, having jurisdiction over the Company or any subsidiary of the Company or any of their properties, (ii) any agreement or instrument to which the Company or any such subsidiary is a party or by which the Company or any such subsidiary is bound or to which any of the properties of the Company or any such subsidiary is subject, or (iii) the charter or by-laws of the Company or any such subsidiary; except in the case of (i) and (ii) where such breach, violation or default would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect. The Company has full power and authority to authorize, issue and sell the Offered Securities as contemplated by this Agreement.

(n) This Agreement has been duly authorized, executed and delivered by the Company.

(o) Except as disclosed in the General Disclosure Package, the Company and its subsidiaries have good and marketable title to all real properties and all other properties and assets owned by them and necessary to the conduct of the business of the Company as described in the General Disclosure Package, in each case free from liens, encumbrances and defects except such as would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect; and except as disclosed in the General Disclosure Package, the Company and its subsidiaries hold

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any leased real or personal property necessary to the conduct of the business of the Company as described in the General Disclosure Package under valid and enforceable leases with no exceptions except such as would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect.

(p) Except as disclosed in the General Disclosure Package, the Company and its subsidiaries possess adequate certificates, authorities or permits issued by appropriate governmental agencies or bodies necessary to conduct the business of the Company as described in the General Disclosure Package, except where the failure to possess such certificates, authorities or permits would not, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect. The Company has not received any notice of proceedings relating to the revocation or modification of any such certificate, authority or permit that, if determined adversely to the Company or any of its subsidiaries, would, individually or in the aggregate, reasonably be expected to result in a Material Adverse Effect.

(q) No labor dispute with the employees of the Company or any subsidiary exists or, to the knowledge of the Company, is imminent that might have a Material Adverse Effect.

(r) The Company and its subsidiaries own, possess or can acquire on reasonable terms, adequate trademarks, trade names and other rights to inventions, know-how, patents, copyrights, confidential information and other intellectual property (collectively, “intellectual property rights”) necessary to conduct the business now operated by them, or presently employed by them, and have not received any notice of infringement of or conflict with asserted rights of others with respect to any intellectual property rights that, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect.

(s) Except as disclosed in the General Disclosure Package, neither the Company nor any of its subsidiaries is in violation of any statute, any 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”), owns or operates any real property contaminated with any substance that is subject to any environmental laws, is liable for any off-site disposal or contamination pursuant to any environmental laws, or is subject to any claim relating to any environmental laws, which violation, contamination, liability or claim would individually or in the aggregate have a Material Adverse Effect; and the Company is not aware of any pending investigation which might lead to such a claim.

(t) Except as disclosed in the General Disclosure Package, there are no pending actions, suits or proceedings against the Company, or any of its subsidiaries or involving any of their respective properties that, if determined adversely to the Company or any of its subsidiaries, would individually or in the aggregate have a Material Adverse Effect, or would materially and adversely affect the ability of the Company to perform its obligations under this Agreement and, to the Company’s knowledge, no such actions, suits or proceedings are threatened or contemplated.

(u) The Company has operated and currently is in compliance with all applicable laws, rules and regulations of the Food and Drug Administration (“FDA”), except where the failure to so operate or be in compliance would not reasonably be expected to have a Material Adverse Effect.

(v) The Company has only conducted clinical trials in the U.S. and Canada. All clinical trials and animal studies conducted by the Company and, to the knowledge of the Company, all clinical trials and animal studies conducted on behalf of the Company or in which the Company has participated were and, if still pending, are being conducted in material compliance with standard

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medical and scientific research practices and, where required, laws, rules and regulations of the FDA, including current Good Clinical Practices and Good Laboratory Practices and all comparable Canadian regulatory requirements and standards.

(w) The financial statements included in each of the Registration Statement and the General Disclosure Package present fairly the financial position of the Company and its consolidated subsidiaries as of the dates shown and their results of operations and cash flows for the periods shown in all material respects, and such financial statements have been prepared in conformity with the generally accepted accounting principles in the United States applied on a consistent basis.

(x) Except as disclosed in the General Disclosure Package, since the date of the latest audited financial statements included in the General Disclosure Package there has been no Material Adverse Effect, nor any development or event involving a prospective Material Adverse Effect, except as disclosed in or contemplated by the General Disclosure Package, there has been no dividend or distribution of any kind declared, paid or made by the Company on any class of its capital stock.

(y) The Company and its Subsidiaries maintain systems of internal accounting controls sufficient to provide reasonable assurances that (i) transactions are 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 generally accepted accounting principles and to maintain asset accountability; (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 the existing assets at reasonable intervals and appropriate action is taken with respect to any difference.

(z) The Company is, or if the Effective Time of the Initial Registration Statement is after the date hereof, as of such Effective Time the Company will be, subject to the reporting requirements of either Section 13 or Section 15(d) of the Securities Exchange Act of 1934.

(aa) The Company is not and, after giving effect to the offering and sale of the Offered Securities and the application of the proceeds thereof as described in the General Disclosure Package, will not be an “investment company” as defined in the Investment Company Act of 1940.

3. Purchase, Sale and Delivery of Offered Securities. 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 sell to the Underwriters, and the Underwriters agree, severally and not jointly, to purchase from the Company, at a purchase price of $                 per share, the respective numbers of shares of Firm Securities set forth opposite the names of the Underwriters in Schedule A hereto.

The Company will deliver the Firm Securities to the Representatives for the accounts of the Underwriters, against payment of the purchase price in Federal (same day) funds by official bank check or checks or wire transfer to an account at a bank acceptable to Bear Stearns or Cowen & Co. drawn to the order of the Company at the office of Latham & Watkins LLP (“Latham & Watkins”), 135 Commonwealth Drive, Menlo Park, CA 94025 at 10:00 A.M., New York time, on                 , or at such other time not later than seven full business days thereafter as Bear Stearns or Cowen & Co. and the Company determine, such time being herein referred to as the “First Closing Date”. For purposes of Rule 15c6-1 under the Securities Exchange Act of 1934, the First Closing Date (if later than the otherwise applicable settlement date) shall be the settlement date for payment of funds and delivery of securities for all the Offered Securities sold pursuant to the offering. The certificates for the Firm Securities so to be

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delivered will be in definitive form, in such denominations and registered in such names as Bear Stearns or Cowen & Co. requests.

In addition, upon written notice from Bear Stearns or Cowen & Co. given to the Company from time to time not more than 30 days subsequent to the date of the Prospectus, the Underwriters may purchase all or less than all of the Optional Securities at the purchase price per Security to be paid for the Firm Securities. The Company agrees to sell to the Underwriters the number of shares of Optional Securities specified in such notice and the Underwriters agree, severally and not jointly, to purchase such Optional Securities. Such Optional Securities shall be purchased for the account of each Underwriter in the same proportion as the number of shares of Firm Securities set forth opposite such Underwriter’s name bears to the total number of shares of Firm Securities on Schedule A hereto (subject to adjustment by Bear Stearns or Cowen & Co. to eliminate fractions) and may be purchased by the Underwriters only for the purpose of covering over-allotments made in connection with the sale of the Firm Securities. No Optional Securities shall be sold or delivered unless the Firm Securities previously have been, or simultaneously are, sold and delivered. The right to purchase the Optional Securities or any portion thereof may be exercised from time to time and to the extent not previously exercised may be surrendered and terminated at any time upon notice by Bear Stearns or Cowen & Co. to the Company given within the 30-day time period specified in the first sentence of this paragraph.

Each time for the delivery of and payment for the Optional Securities, being herein referred to as an “Optional Closing Date”, which may be the First Closing Date (the First Closing Date and each Optional Closing Date, if any, being sometimes referred to as a “Closing Date”), shall be determined by Bear Stearns or Cowen & Co. but shall be not later than five full business days after written notice of election to purchase Optional Securities is given. The Company will deliver the Optional Securities being purchased on each Optional Closing Date to the Representatives for the accounts of the several Underwriters, against payment of the purchase price therefor in Federal (same day) funds by official bank check or checks or wire transfer to an account at a bank acceptable to Bear Stearns or Cowen & Co. drawn to the order of the Company, at the above office of Latham & Watkins. The certificates for the Optional Securities being purchased on each Optional Closing Date will be in definitive form, in such denominations and registered in such names as Bear Stearns or Cowen & Co. requests upon reasonable notice prior to such Optional Closing Date.

4. Offering by Underwriters. It is understood that the several Underwriters propose to offer the Offered Securities for sale to the public as set forth in the Prospectus.

5. Certain Agreements of the Company. The Company agrees with the several Underwriters that:

(a) If the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement, the Company will file the Prospectus with the Commission pursuant to and in accordance with subparagraph (1) (or, if applicable and if consented to by Bear Stearns and Cowen & Co., subparagraph (4)) of Rule 424(b) not later than the earlier of (A) the second business day following the execution and delivery of this Agreement or (B) the fifteenth business day after the Effective Date of the Initial Registration Statement. The Company will advise Bear Stearns and Cowen & Co. promptly of any such filing pursuant to Rule 424(b). If the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement and an additional registration statement is necessary to register a portion of the Offered Securities under the Act but the Effective Time thereof has not occurred as of such execution and delivery, the Company will file the additional registration statement or, if filed, will file a post-effective amendment thereto with the Commission pursuant to and in accordance with Rule 462(b) on or prior to 10:00 P.M., New York time, on the date of this Agreement or, if earlier, on or prior to the time the Prospectus is printed and distributed to any Underwriter, or will make such filing at such later date as shall have been consented to by Bear Stearns and Cowen & Co.

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(b) The Company will advise Bear Stearns and Cowen & Co. promptly of any proposal to amend or supplement at any time the Initial Registration Statement, the Additional Registration Statement (if any) or any Statutory Prospectus and will not effect such amendment or supplementation without Bear Stearns and Cowen & Co.’s consent, which consent shall not be unreasonably withheld, and the Company will also advise Bear Stearns and Cowen & Co. promptly of the effectiveness of each Registration Statement (if its Effective Time is subsequent to the execution and delivery of this Agreement) and of any amendment or supplementation of a Registration Statement or any Statutory Prospectus and of the institution by the Commission of any stop order proceedings in respect of a Registration Statement and will use its best efforts to prevent the issuance of any such stop order and to obtain as soon as possible its lifting, if issued.

(c) If, at any time when a prospectus relating to the Offered Securities is (or but for the exemption in Rule 172 would be required to be) delivered under the Act in connection with sales by any Underwriter or dealer, any event occurs as a result of which the Prospectus as then amended or supplemented would include an untrue statement of a material fact or omit to state any material fact necessary to make the statements therein, in the light of the circumstances under which they were made, not misleading, or if it is necessary at any time to amend the Prospectus to comply with the Act, the Company will (i) promptly notify Bear Stearns and Cowen & Co. of such event and (ii) promptly prepare and file with the Commission, at its own expense, an amendment or supplement which will correct such statement or omission or an amendment which will effect such compliance. Neither Bear Stearns nor Cowen & Co.’s consent to, nor the Underwriters’ delivery of, any such amendment or supplement shall constitute a waiver of any of the conditions set forth in Section 6.

(d) As soon as practicable, but not later than the Availability Date (as defined below), the Company will make generally available to its securityholders an earnings statement covering a period of at least 12 months beginning after the Effective Date of the Initial Registration Statement (or, if later, the Effective Date of the Additional Registration Statement) which will satisfy the provisions of Section 11(a) of the Act. For the purpose of the preceding sentence, “Availability Date” means the 45th day after the end of the fourth fiscal quarter following the fiscal quarter that includes such Effective Date, except that, if such fourth fiscal quarter is the last quarter of the Company’s fiscal year, “Availability Date” means the 90th day after the end of such fourth fiscal quarter.

(e) The Company will furnish to the Representatives copies of each Registration Statement (four of which will be signed and will include all exhibits), each related preliminary prospectus, and, so long as a prospectus relating to the Offered Securities is required to be delivered under the Act in connection with sales by any Underwriter or dealer, the Prospectus and all amendments and supplements to such documents, in each case in such quantities as Bear Stearns and Cowen & Co. request. The Prospectus shall be so furnished on or prior to 3:00 P.M., New York time, on the second business day following the later of the execution and delivery of this Agreement or the Effective Time of the Initial Registration Statement. All other documents shall be so furnished as soon as available. The Company will pay the expenses of printing and distributing to the Underwriters all such documents as the Underwriters may reasonably request.

(f) The Company will arrange for the qualification of the Offered Securities for sale under the laws of such jurisdictions as Bear Stearns and Cowen & Co. designate and will continue such qualifications in effect so long as required for the distribution; provided that the Company shall in no event be obligated to qualify to do business in any jurisdiction where it is not now so qualified or to take any action that would subject the Company to taxation or to service of process.

(g) The Company will pay (i) all expenses incident to the performance of its obligations under this Agreement, (ii) for any filing fees and other expenses (including fees and disbursements of counsel to the Underwriters) incurred in connection with qualification of the Offered Securities

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for sale under the laws of such jurisdictions as Bear Stearns and Cowen & Co. designate and the printing of memoranda relating thereto, (iii) for any filing fees and other expenses (including fees and disbursements of counsel to the Underwriters) incurred in connection with the review and qualification of the offering of the Offered Securities by the NASD, (iv) for any travel expenses of the Company’s officers and employees and any other expenses of the Company in connection with attending or hosting meetings with prospective purchasers of the Offered Securities, including the cost of any aircraft chartered in connection with attending or hosting such meetings; (v) for expenses incurred in distributing preliminary prospectuses and the Prospectus (including any amendments and supplements thereto) to the Underwriters and (vi) for expenses incurred for preparing, printing and distributing any Issuer Free Writing Prospectuses to investors or prospective investors.

(h) Except for the issuance and sale of the Offered Securities pursuant to this Agreement, for the period specified below (the “Lock-Up Period”), the Company will not offer, sell, contract to sell, pledge or otherwise dispose of, directly or indirectly, or file with the Commission a registration statement under the Act relating to, any additional shares of its Securities or securities convertible into or exchangeable or exercisable for any shares of its Securities, or publicly disclose the intention to make any such offer, sale, pledge, disposition or filing, without the prior written consent of Bear Stearns and Cowen & Co., except that the Company may (i) issue Securities pursuant to the conversion or exchange of convertible or exchangeable securities or upon the exercise of warrants or options, in each case outstanding on the date hereof, (ii) grant stock options or restricted stock awards or other equity awards pursuant to any stock option, stock bonus or other stock plan or arrangement described in the Prospectus (the “Disclosed Plans”), (iii) issue Securities pursuant to such Disclosed Plans or upon the exercise of options or grants under such Disclosed Plans, (iv) file registration statements on Form S-8 with the Commission registering the Securities issuable under the Disclosed Plans, (v) issue Securities pursuant to that certain License Agreement, dated as of July 1, 2002, between the Company and the University of Pittsburgh of the Commonwealth System of Higher Education and (vi) issue up to an aggregate of 5% of the Company’s outstanding Securities (outstanding immediately after the offering and sale of the Offered Securities) (x) in connection with joint ventures, marketing or distribution arrangements, collaboration agreements or intellectual property license agreements entered into between the Company and the recipient of such Securities or (y) as consideration in connection with the acquisition by the Company of any businesses, products or technologies; provided, however, that it shall be a pre-condition to any issuance pursuant to subclauses (vi)(x) and (vi)(y) above that prior to the Company’s entering into any definitive agreement that contemplates such an issuance, any potential recipients of such Securities shall have agreed in writing to be bound by the restrictions in this Section 5(h)). The initial Lock-Up Period will commence on the date hereof and will continue and include the date 180 days after the date hereof or such earlier date that Bear Stearns and Cowen & Co. consent to in writing; provided, however, that if (1) during the last 17 days of the initial Lock-Up Period, the Company releases earnings results or material news or a material event relating to the Company occurs or (2) prior to the expiration of the initial Lock-Up Period, the Company announces that it will release earnings results during the 16-day period beginning on the last day of the initial Lock-Up Period, then solely for the purposes of allowing the Underwriters to comply with NASD Rule 2711(f)(4) 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 occurrence of the materials news or material event, as applicable, unless Bear Stearns or Cowen & Co. waives, in writing, such extension. The Company will provide Bear Stearns and Cowen & Co. with notice of any announcement described in clause (2) of the preceding sentence that gives rise to an extension of the Lock-Up Period.

6. Free Writing Prospectuses. The Company represents and agrees that, unless it obtains the prior consent of Bear Stearns and Cowen & Co., and each Underwriter represents and agrees that, unless it obtains the prior consent of the Company, Bear Stearns and Cowen & Co., it has not made and will not make any offer relating to the Offered Securities that would constitute an Issuer

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Free Writing Prospectus, or that would otherwise constitute a “free writing prospectus,” as defined in Rule 405, required to be filed with the Commission, provided that the prior written consent of the parties hereto shall be deemed to have been given with respect to any Issuer Free Writing Prospectus set forth on Schedule C hereto and with respect to the electronic roadshow made available on NetRoadshow.com and RetailRoadshow.com. Any such free writing prospectus consented to by the Company, Bear Stearns and Cowen & Co., including those set forth on Schedule C hereto, is hereinafter referred to as a “Permitted Free Writing Prospectus.” The Company represents that it has treated and 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 Rules 164 and 433 applicable to any Permitted Free Writing Prospectus, including timely Commission filing where required, legending and record keeping.

7. Conditions of the Obligations of the Underwriters. The obligations of the several Underwriters to purchase and pay for the Firm Securities on the First Closing Date and the Optional Securities to be purchased on each Optional Closing Date will be subject to the accuracy of the representations and warranties on the part of the Company herein, to the accuracy of the statements of Company officers made pursuant to the provisions hereof, to the performance by the Company of its obligations hereunder and to the following additional conditions precedent:

(a) The Representatives shall have received a letter, dated the date of delivery thereof (which, if the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement, shall be on or prior to the date of this Agreement or, if the Effective Time of the Initial Registration Statement is subsequent to the execution and delivery of this Agreement, shall be prior to the filing of the amendment or post-effective amendment to the registration statement to be filed shortly prior to such Effective Time), of Ernst & Young LLP confirming that they are independent public accountants within the meaning of the Act and the applicable published Rules and Regulations thereunder and stating to the effect that:

(i) in their opinion the financial statements and schedules examined by them and included in the Registration Statements and the General Disclosure Package comply as to form in all material respects with the applicable accounting requirements of the Act and the related published Rules and Regulations;

(ii) on the basis of a reading of the latest available interim financial statements of the Company, inquiries of officials of the Company who have responsibility for financial and accounting matters and other specified procedures, nothing came to their attention that caused them to believe that:

(A) at the date of the latest available balance sheet read by such accountants, or at a subsequent specified date not more than three business days prior to the date of this Agreement, there was any change in the capital stock or any increase in short-term indebtedness or long-term debt of the Company and its consolidated subsidiaries or, at the date of the latest available balance sheet read by such accountants, there was any decrease in consolidated net current assets or stockholders’ equity as compared with amounts shown on the latest balance sheet included in the General Disclosure Package; or

(B) for the period from the closing date of the latest income statement included in the General Disclosure Package to the closing date of the latest available income statement read by such accountants there were any decreases, as compared with the corresponding period of the previous year, in revenues or increases in net loss,

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except in all cases for changes, increases or decreases which the General Disclosure Package discloses have occurred or may occur or which are described in such letter; and

(iv) they have compared specified dollar amounts (or percentages derived from such dollar amounts) and other financial information contained in the Registration Statements, each Statutory Prospectus and each Issuer Free Writing Prospectus (other than any Issuer Free Writing Prospectus that is an “electronic road show,” as defined in Rule 433(h)) and the General Disclosure Package (in each case to the extent that such dollar amounts, percentages and other financial information are derived from the general accounting records of the Company and its subsidiaries subject to the internal controls of the Company’s accounting system or are derived directly from such records by analysis or computation) with the results obtained from inquiries, a reading of such general accounting records and other procedures specified in such letter and have found such dollar amounts, percentages and other financial information to be in agreement with such results, except as otherwise specified in such letter.

For purposes of this subsection (a), (i) if the Effective Time of the Initial Registration Statement is subsequent to the execution and delivery of this Agreement, “Registration Statements” shall mean the initial registration statement as proposed to be amended by the amendment or post-effective amendment to be filed shortly prior to its Effective Time, (ii) if the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement but the Effective Time of the Additional Registration Statement (if any) is subsequent to such execution and delivery, “Registration Statements” shall mean the Initial Registration Statement and the additional registration statement as proposed to be filed or as proposed to be amended by the post-effective amendment to be filed shortly prior to its Effective Time, and (iii) “Prospectus” shall mean the prospectus included in the Registration Statements.

(b) If the Effective Time of the Initial Registration Statement is not prior to the execution and delivery of this Agreement, such Effective Time shall have occurred not later than 10:00 P.M., New York time, on the date of this Agreement or such later date as shall have been consented to by Bear Stearns and Cowen & Co. If the Effective Time of the Additional Registration Statement (if any) is not prior to the execution and delivery of this Agreement, such Effective Time shall have occurred not later than 10:00 P.M., New York time, on the date of this Agreement or, if earlier, the time the Prospectus is printed and distributed to any Underwriter, or shall have occurred at such later date as shall have been consented to by Bear Stearns and Cowen & Co. If the Effective Time of the Initial Registration Statement is prior to the execution and delivery of this Agreement, the Prospectus shall have been filed with the Commission in accordance with the Rules and Regulations and Section 5(a) of this Agreement. Prior to such Closing Date, no stop order suspending the effectiveness of a Registration Statement shall have been issued and no proceedings for that purpose shall have been instituted or, to the knowledge of the Company or the Representatives, shall be contemplated by the Commission.

(c) Subsequent to the execution and delivery of this Agreement, there shall not have occurred (i) any change, or any development or event involving a prospective change, in the condition (financial or other), business, properties or results of operations of the Company and its subsidiaries taken as a whole which, in the judgment of a majority in interest of the Underwriters including the Representatives, is material and adverse and makes it impractical or inadvisable to proceed with completion of the public offering or the sale of and payment for the Offered Securities; (ii) any downgrading in the rating of any debt securities of the Company by any “nationally recognized statistical rating organization” (as defined for purposes of Rule 436(g) under the Act), or any public announcement that any such organization has under surveillance or review its rating of any debt securities of the Company (other than an announcement with positive implications of a possible upgrading, and no implication of a possible downgrading, of such rating); (iii) any change in U.S. or international financial, political or economic conditions as

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would, in the judgment of a majority in interest of the Underwriters including the Representatives, be likely to prejudice materially the success of the proposed issue, sale or distribution of the Offered Securities, whether in the primary market or in respect of dealings in the secondary market; (iv) any material suspension or material limitation of trading in securities generally on the New York Stock Exchange, or any setting of minimum prices for trading on such exchange; (v) or any suspension of trading of any securities of the Company on any exchange or in the over-the-counter market; (vi) any banking moratorium declared by U.S. Federal or New York authorities; (vii) any substantial disruption of settlements of securities or clearance services in the United States or (viii) any attack on, outbreak or escalation of hostilities or act of terrorism involving the United States, any declaration of war by Congress or any other national or international calamity or emergency if, in the judgment of a majority in interest of the Underwriters including the Representatives, the effect of any such attack, outbreak, escalation, act, declaration, calamity or emergency makes it impractical or inadvisable to proceed with completion of the public offering or the sale of and payment for the Offered Securities.

(d) The Representatives shall have received an opinion, dated such Closing Date, of Latham & Watkins LLP, counsel for the Company, substantially in the form attached hereto as Exhibit A.

(e) The Representatives shall have received a letter, dated such Closing Date, of Latham & Watkins LLP, counsel to the Company, substantially in the form attached hereto as Exhibit B.

(f) The Representatives shall have received an opinion, dated such Closing Date, of Sterne Kessler Goldstein Fox P.L.L.C., intellectual property counsel for the Company, substantially in the form attached hereto as Exhibit C.

(g) The Representatives shall have received from Davis Polk & Wardwell, counsel for the Underwriters, such opinion or opinions, dated such Closing Date, with respect to the incorporation of the Company, the validity of the Offered Securities delivered on such Closing Date, the Registration Statements, the Prospectus and other related matters as the Representatives may require, and the Company shall have furnished to such counsel such documents as they request for the purpose of enabling them to pass upon such matters.

(h) The Representatives shall have received a certificate, dated such Closing Date, of the Chief Executive Officer or any Vice President and a principal financial or accounting officer of the Company in which such officers, to the best of their knowledge after reasonable investigation, shall state that: the representations and warranties of the Company in this Agreement are true and correct; the Company has complied in all material respects with all agreements and satisfied all conditions on its part to be performed or satisfied hereunder at or prior to such Closing Date; no stop order suspending the effectiveness of any Registration Statement has been issued and no proceedings for that purpose have been instituted or are contemplated by the Commission; the Additional Registration Statement (if any) satisfying the requirements of subparagraphs (1) and (3) of Rule 462(b) was filed pursuant to Rule 462(b), including payment of the applicable filing fee in accordance with Rule 111(a) or (b) under the Act, prior to the Applicable Time; and, subsequent to the dates of the most recent financial statements in the General Disclosure Package, there has been no Material Adverse Effect, nor any development or event involving a prospective Material Adverse Effect, except as set forth in the General Disclosure Package or as described in such certificate.

(i) The Representatives shall have received a letter, dated such Closing Date, of Ernst & Young LLP which meets the requirements of subsection (a) of this Section, except that the specified date referred to in such subsection will be a date not more than three days prior to such Closing Date for the purposes of this subsection.

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(j) On or prior to the date of this Agreement, the Representatives shall have received lockup letters from each of the executive officers and directors of the Company and from holders of all outstanding shares of Common Stock or securities convertible into Common Stock of the Company, and holders of all outstanding options to purchase shares of common stock or shares of securities convertible into Common Stock of the Company.

The Company will furnish the Representatives with such conformed copies of such opinions, certificates, letters and documents as the Representatives reasonably request. Bear Stearns and Cowen & Co. may in their sole discretion waive on behalf of the Underwriters compliance with any conditions to the obligations of the Underwriters hereunder, whether in respect of an Optional Closing Date or otherwise.

8. Indemnification and Contribution. (a) The Company will indemnify and hold harmless each Underwriter, its partners, members, directors, officers, affiliates and each person, if any, who controls such Underwriter within the meaning of Section 15 of the Act, against any losses, claims, damages or liabilities, joint or several, to which such Underwriter may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in any Registration Statement, each Statutory Prospectus, the Prospectus, any Issuer Free Writing Prospectus or any amendment or supplement thereto, or any related preliminary prospectus, or arise out of or are based upon the omission or alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, and will reimburse each Underwriter for any legal or other expenses reasonably incurred by such Underwriter in connection with investigating or defending any such loss, claim, damage, liability or action as such expenses are incurred; provided, however, that the Company will not be liable in any such case to the extent that any such loss, claim, damage or liability arises out of or is based upon an untrue statement or alleged untrue statement in or omission or alleged omission from any of such documents in reliance upon and in conformity with written information furnished to the Company by any Underwriter through the Representatives specifically for use therein, it being understood and agreed that the only such information furnished by any Underwriter consists of the information described as such in subsection (b) below.

(b) Each Underwriter will severally and not jointly indemnify and hold harmless the Company, its directors and officers and each person, if any who controls the Company within the meaning of Section 15 of the Act, against any losses, claims, damages or liabilities to which the Company may become subject, under the Act or otherwise, insofar as such losses, claims, damages or liabilities (or actions in respect thereof) arise out of or are based upon any untrue statement or alleged untrue statement of any material fact contained in any Registration Statement, each Statutory Prospectus, the Prospectus, any Issuer Free Writing Prospectus, or any amendment or supplement thereto, or any related preliminary prospectus, or arise out of or are based upon the omission or the alleged omission to state therein a material fact required to be stated therein or necessary to make the statements therein not misleading, in each case to the extent, but only to the extent, that such untrue statement or alleged untrue statement or omission or alleged omission was made in reliance upon and in conformity with written information furnished to the Company by such Underwriter through the Representatives specifically for use therein, and will reimburse any legal or other expenses reasonably incurred by the Company in connection with investigating or defending any such loss, claim, damage, liability or action as such expenses are incurred, it being understood and agreed that the only such information furnished by any Underwriter consists of the following information in the Prospectus furnished on behalf of each Underwriter: (i) the sentences related to concessions and reallowances appearing under the caption “Underwriting”, and (ii) the paragraph under the caption “Underwriting” related to stabilization, the statements in the fourth, sixth, twelfth, thirteenth and fourteenth full paragraphs appearing in the caption “Underwriting” relating to broker/dealer concessions and reallowances, sales to accounts over which the underwriters have discretionary authority, stabilizing transactions, over-allotment transactions, syndicate covering transactions and penalty bids and the electronic prospectuses, respectively.

(c) Promptly after receipt by an indemnified party under this Section of notice of the commencement of any action, such indemnified party will, if a claim in respect thereof is to be made

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against the indemnifying party under subsection (a) or (b) above, notify the indemnifying party of the commencement thereof; but the failure to notify the indemnifying party shall not relieve it from any liability that it may have under subsection (a) or (b) above except to the extent that it has been materially prejudiced (through the forfeiture of substantive rights or defenses) by such failure; and provided further that the failure to notify the indemnifying party shall not relieve it from any liability that it may have to an indemnified party otherwise than under subsection (a) or (b) above. In case any such action is brought against any indemnified party and it notifies the indemnifying party of the commencement thereof, the indemnifying party will be entitled to participate therein and, to the extent that it may wish, jointly with any other indemnifying party similarly notified, to assume the defense thereof, with counsel satisfactory to such indemnified party (who shall not, except with the consent of the indemnified party, be counsel to the indemnifying party), and after notice from the indemnifying party to such indemnified party of its election so to assume the defense thereof, the indemnifying party will not be liable to such indemnified party under this Section 8 for any legal or other expenses subsequently incurred by such indemnified party in connection with the defense thereof other than reasonable costs of investigation. No indemnifying party shall, without the prior written consent of the indemnified party, effect any settlement of any pending or threatened action in respect of which any indemnified party is or could have been a party and indemnity could have been sought hereunder by such indemnified party unless such settlement (i) includes an unconditional release of such indemnified party from all liability on any claims that are the subject matter of such action and (ii) does not include a statement as to, or an admission of, fault, culpability or a failure to act by or on behalf of an indemnified party.

(d) If the indemnification provided for in this Section is unavailable or insufficient to hold harmless an indemnified party under subsection (a) or (b) above, then each indemnifying party shall contribute to the amount paid or payable by such indemnified party as a result of the losses, claims, damages or liabilities referred to in subsection (a) or (b) above (i) in such proportion as is appropriate to reflect the relative benefits received by the Company on the one hand and the Underwriters on the other from the offering of the Securities or (ii) if the allocation provided by clause (i) above is not permitted by applicable law, in such proportion as is appropriate to reflect not only the relative benefits referred to in clause (i) above but also the relative fault of the Company on the one hand and the Underwriters on the other in connection with the statements or omissions which resulted in such losses, claims, damages or liabilities as well as any other relevant equitable considerations. The relative benefits received by the Company on the one hand and the Underwriters on the other shall be deemed to be in the same proportion as the total net proceeds from the offering (before deducting expenses) received by the Company bear to the total underwriting discounts and commissions received by the Underwriters. The relative fault shall be determined by reference to, among other things, whether the untrue or alleged untrue statement of a material fact or the omission or alleged omission to state a material fact relates to information supplied by the Company or the Underwriters and the parties’ relative intent, knowledge, access to information and opportunity to correct or prevent such untrue statement or omission. The amount paid by an indemnified party as a result of the losses, claims, damages or liabilities referred to in the first sentence of this subsection (d) shall be deemed to include any legal or other expenses reasonably incurred by such indemnified party in connection with investigating or defending any action or claim which is the subject of this subsection (d). Notwithstanding the provisions of this subsection (d), no Underwriter shall be required to contribute any amount in excess of the amount by which the total price at which the Securities underwritten by it and distributed to the public were offered to the public exceeds the amount of any damages which such Underwriter has otherwise been required to pay by reason of such untrue or alleged untrue statement or omission or alleged omission. No person guilty of fraudulent misrepresentation (within the meaning of Section 11(f) of the Act) shall be entitled to contribution from any person who was not guilty of such fraudulent misrepresentation. The Underwriters’ obligations in this subsection (d) to contribute are several in proportion to their respective underwriting obligations and not joint.

(e) The obligations of the Company under this Section 8 shall be in addition to any liability which the Company may otherwise have and shall extend, upon the same terms and conditions, to each person, if any, who controls any Underwriter within the meaning of the Act; and the obligations of the Underwriters under this Section 8 shall be in addition to any liability which the respective Underwriters may otherwise

15

have and shall extend, upon the same terms and conditions, to each director of the Company, to each officer of the Company who has signed a Registration Statement and to each person, if any, who controls the Company within the meaning of the Act.

9. Default of Underwriters. If any Underwriter or Underwriters default in their obligations to purchase Offered Securities hereunder on either the First or any Optional Closing Date and the aggregate number of shares of Offered Securities that such defaulting Underwriter or Underwriters agreed but failed to purchase does not exceed 10% of the total number of shares of Offered Securities that the Underwriters are obligated to purchase on such Closing Date, Bear Stearns and Cowen & Co. may make arrangements satisfactory to the Company for the purchase of such Offered Securities by other persons, including any of the Underwriters, but if no such arrangements are made by such Closing Date, the non-defaulting Underwriters shall be obligated severally, in proportion to their respective proportions that the number of shares of Firm Securities set forth opposite the name of each non-defaulting Underwriter on Schedule A hereto bears to the total number of shares of Firm Securities set forth opposite the names of all Underwriters on Schedule A hereto, to purchase the Offered Securities that such defaulting Underwriters agreed but failed to purchase on such Closing Date. If any Underwriter or Underwriters so default and the aggregate number of shares of Offered Securities with respect to which such default or defaults occur exceeds 10% of the total number of shares of Offered Securities that the Underwriters are obligated to purchase on such Closing Date and arrangements satisfactory to Bear Stearns or Cowen & Co. and the Company for the purchase of such Offered Securities by other persons are not made within 36 hours after such default, this Agreement will terminate without liability on the part of any non-defaulting Underwriter or the Company, except as provided in Section 10 (provided that if such default occurs with respect to Optional Securities after the First Closing Date, this Agreement will not terminate as to the Firm Securities or any Optional Securities purchased prior to such termination). As used in this Agreement, the term “Underwriter” includes any person substituted for an Underwriter under this Section. Nothing herein will relieve a defaulting Underwriter from liability for its default.

10. Survival of Certain Representations and Obligations. The respective indemnities, agreements, representations, warranties and other statements of the Company or its officers and of the several Underwriters set forth in or made pursuant to this Agreement will remain in full force and effect, regardless of any investigation, or statement as to the results thereof, made by or on behalf of any Underwriter, the Company or any of their respective representatives, officers or directors or any controlling person, and will survive delivery of and payment for the Offered Securities. If this Agreement is terminated pursuant to Section 9 or if for any reason the purchase of the Offered Securities by the Underwriters is not consummated, the Company shall remain responsible for the expenses to be paid or reimbursed by it pursuant to Section 5 and the respective obligations of the Company and the Underwriters pursuant to Section 8 shall remain in effect, and if any Offered Securities have been purchased hereunder the representations and warranties in Section 2 and all obligations under Section 5 shall also remain in effect. If the purchase of the Offered Securities by the Underwriters is not consummated for any reason other than solely because of the termination of this Agreement pursuant to Section 9 or the occurrence of any event specified in clause (iii), (iv), (v), (vi), (vii) or (viii) of Section 7(c), the Company will reimburse the Underwriters for all out-of-pocket expenses (including fees and disbursements of counsel) reasonably incurred by them in connection with the offering of the Offered Securities.

11. Notices. All communications hereunder will be in writing and, if sent to the Underwriters, will be mailed, delivered or telegraphed and confirmed to the Representatives, c/o Bear Stearns & Co. Inc., 383 Madison Avenue, New York, NY 10179, Attention:                      and Cowen & Co., LLC 1221 Avenue of the Americas, New York, NY 10020, Attention:                     , or, if sent to the Company, will be mailed, delivered or telegraphed and confirmed to it at 601 Gateway Blvd., Suite 800, South San Francisco, CA 94080, Attention: Bradford S. Goodwin; provided, however, that any notice to an Underwriter pursuant to Section 8 will be mailed, delivered or telegraphed and confirmed to such Underwriter.

12. Successors. This Agreement will inure to the benefit of and be binding upon the parties hereto and their respective successors and the officers and directors and controlling persons referred to in Section 8, and no other person will have any right or obligation hereunder.

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13. Representation of Underwriters. The Representatives will act for the several Underwriters in connection with this financing, and any action under this Agreement taken by the Representatives jointly or by Cowen & Co. or Bear Stearns will be binding upon all the Underwriters.

14. Counterparts. This Agreement may be executed in any number of counterparts, each of which shall be deemed to be an original, but all such counterparts shall together constitute one and the same Agreement.

15. Absence of Fiduciary Relationship. The Company acknowledges and agrees that:

(a) The Representatives have been retained solely to act as underwriters in connection with the sale of Company’s common stock and that no fiduciary, advisory or agency relationship between the Company and the Representatives has been created in respect of any of the transactions contemplated by this Agreement, irrespective of whether the Representatives have advised or are advising the Company on other matters;

(b) the price of the Securities set forth in this Agreement was established by the Company following discussions and arms-length negotiations with the Representatives and the Company is capable of evaluating and understanding and understands and accepts the terms, risks and conditions of the transactions contemplated by this Agreement;

(c) it has been advised that the Representatives and their affiliates are engaged in a broad range of transactions which may involve interests that differ from those of the Company and that the Representatives have no obligation to disclose such interests and transactions to the Company by virtue of any fiduciary, advisory or agency relationship; and

(d) it waives, to the fullest extent permitted by law, any claims it may have against the Representatives for breach of fiduciary duty or alleged breach of fiduciary duty and agrees that the Representatives shall have no liability (whether direct or indirect) to the Company in respect of such a fiduciary duty claim or to any person asserting a fiduciary duty claim on behalf of or in right of the Company, including stockholders, employees or creditors of the Company.

16. Applicable Law. This Agreement shall be governed by, and construed in accordance with, the laws of the State of New York, without regard to principles of conflicts of laws.

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If the foregoing is in accordance with the Representatives’ understanding of our agreement, kindly sign and return to the Company one of the counterparts hereof, whereupon it will become a binding agreement between the Company and the several Underwriters in accordance with its terms.

Very truly yours,

NOVACEA, INC.

By:                                                                                                       

Title:                                                                                                   

The foregoing Underwriting Agreement is hereby

    confirmed and accepted as of the date first above

    written.

BEAR STEARNS & CO. INC.

COWEN & CO., LLC

PACIFIC GROWTH EQUITIES, LLC

HSBC SECURITIES (USA)

Acting on behalf of themselves and as the

    Representatives of the several

    Underwriters

By: BEAR STEARNS & CO. INC.

By:                                                                                        

Title:                                                                                    

By: COWEN & CO., LLC

By:                                                                                        

Title:                                                                                     

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SCHEDULE A

SCHEDULE B

The initial public offering price of the Offered Securities is $                 per share.

SCHEDULE C

General Disclosure Package

APPENDIX I

GENERAL USE ISSUER FREE WRITING PROSPECTUSES