SIRNA THERAPEUTICS, INC. WARRANT TO PURCHASE ________ SHARES OF COMMON STOCK

EXHIBIT C

THIS WARRANT AND THE SHARES OF COMMON STOCK TO BE ISSUED UPON EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED, OR ANY STATE SECURITIES LAWS. NO SALE OR DISPOSITION MAY BE EFFECTED WITHOUT (I) AN EFFECTIVE REGISTRATION STATEMENT RELATED THERETO, (II) AN OPINION OF COUNSEL OR OTHER EVIDENCE, REASONABLY SATISFACTORY TO THE COMPANY, THAT SUCH REGISTRATION IS NOT REQUIRED, (III) RECEIPT OF NO-ACTION LETTERS FROM THE APPROPRIATE GOVERNMENTAL AUTHORITIES, OR (IV) OTHERWISE COMPLYING WITH THE PROVISIONS OF SECTION 7 OF THIS WARRANT.

SIRNA THERAPEUTICS, INC.

WARRANT TO PURCHASE ________ SHARES
OF COMMON STOCK

Warrant No. W-[          ]

     THIS CERTIFIES THAT, for value received, ___ and its assigns are entitled to subscribe for and purchase ___shares (as adjusted pursuant to Section 4 hereof, the “Shares”) of the fully paid and nonassessable common stock, par value $0.01 per share (“Common Stock”), of Sirna Therapeutics, Inc., a Delaware corporation (the “Company”), at the price of $3.85 per share (such price and such other price as shall result, from time to time, from the adjustments specified in Section 4 hereof is herein referred to as the “Warrant Price”), subject to the provisions and upon the terms and conditions set forth herein and in the Warrant Exchange Agreement, dated as of even date herewith, by and among the Company and the other parties thereto. As used herein, the term “Date of Grant” means December 30, 2004. As used herein, the term “Warrant” shall be deemed to include any warrants issued in exchange or upon transfer or partial exercise of this Warrant unless the context clearly requires otherwise. Notwithstanding any other provision in this Warrant to the contrary, if a reduction in the Warrant Price pursuant to Section 4 would require the Company to obtain stockholder approval of the transactions giving rise to this Warrant pursuant to Nasdaq Marketplace Rules, then the Warrant Price shall be reduced to the maximum extent that would not require stockholder approval under such rules.

     1.      Term. The purchase right represented by this Warrant is exercisable, in whole or in part, at any time and from time to time from the Date of Grant through December 30, 2009.

     2.      Method of Exercise; Payment; Issuance of New Warrant. Subject to Section 1 hereof, the purchase right represented by this Warrant may be exercised by the holder hereof, in whole or in part and from time to time, at the election of the holder hereof, by (a) the surrender of this Warrant (with the notice of exercise substantially in the form attached hereto as Exhibit A-1 duly completed and executed) at the principal office of the Company and by the payment to the Company, by certified or bank check, or by wire transfer to an account designated by the Company (a “Wire Transfer”) of an amount equal to the then applicable Warrant Price multiplied by the number of Shares then being purchased or (b) if in connection with a registered public offering of the Company’s securities, the surrender of this Warrant (with

the notice of exercise form attached hereto as Exhibit A-2 duly completed and executed) at the principal office of the Company together with notice of arrangements reasonably satisfactory to the Company for payment to the Company either by certified or bank check or by Wire Transfer from the proceeds of the sale of Shares to be sold by the holder in such public offering of an amount equal to the then applicable Warrant Price per share multiplied by the number of Shares then being purchased, or (c) exercise of the “net issuance” right provided for in Section 10.2 hereof. The person or persons in whose name(s) any certificate(s) representing the Shares shall be issuable upon exercise of this Warrant shall be deemed to have become the holder(s) of record of, and shall be treated for all purposes as the record holder(s) of, the Shares represented thereby (and such Shares shall be deemed to have been issued) immediately prior to the close of business on the date or dates upon which this Warrant is exercised. In the event of any exercise of the rights represented by this Warrant, certificates for the Shares of stock so purchased shall be delivered to the holder hereof as soon as practicable and, if requested by the holder of this Warrant, the Company shall cause its transfer agent to deliver the certificate representing Shares issued upon exercise of this Warrant to a broker or other person (as directed by the holder exercising this Warrant) within the time period required to settle any trade made by the holder after exercise of this Warrant.

     3.      Stock Fully Paid; Reservation of Shares. All Shares that may be issued upon the exercise of the rights represented by this Warrant will, upon issuance pursuant to the terms and conditions herein, be fully paid and nonassessable, and free from all taxes, liens and charges with respect to the issue thereof. During the period within which the rights represented by this Warrant may be exercised, the Company will at all times have authorized, and reserved for the purpose of the issue upon exercise of the purchase rights evidenced by this Warrant, a sufficient number of shares of its Common Stock to provide for the exercise of the rights represented by this Warrant.

     4.      Adjustment of Warrant Price and Number of Shares. The number and kind of securities purchasable upon the exercise of this Warrant and the Warrant Price shall be subject to adjustment from time to time upon the occurrence of certain events, as follows:

     (a)      Reclassification or Merger. In case of any reclassification or change of securities of the class issuable upon exercise of this Warrant (other than a change in par value, or from par value to no par value, or from no par value to par value, or as a result of a subdivision or combination), or in case of any merger of the Company with or into another corporation (other than a merger with another corporation in which the Company is the acquiring and the surviving corporation and which does not result in any reclassification or change of outstanding securities issuable upon exercise of this Warrant), or in case of any sale of all or substantially all of the assets of the Company, the Company, or such successor or purchasing corporation, as the case may be, shall duly execute and deliver to the holder of this Warrant a new Warrant (in form and substance satisfactory to the holder of this Warrant), or the Company shall make appropriate provision without the issuance of a new Warrant, so that the holder of this Warrant shall have the right to receive upon exercise of this Warrant, at a total purchase price not to exceed that payable upon the exercise of the unexercised portion of this Warrant, and in lieu of the shares of Common Stock theretofore issuable upon exercise of this Warrant,

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the kind and amount of shares of stock, other securities, money and property receivable upon such reclassification, change or merger by a holder of the number of shares of Common Stock then purchasable under this Warrant. Such new Warrant shall provide for adjustments that shall be as nearly equivalent as may be practicable to the adjustments provided for in this Section 4. The provisions of this subparagraph (a) shall similarly apply to successive reclassifications, changes, mergers and transfers.

     (b) Subdivision or Combination of Shares. If the Company at any time while this Warrant remains outstanding and unexpired shall subdivide or combine its outstanding shares of Common Stock, the Warrant Price shall be proportionately decreased and the number of Shares issuable hereunder shall be proportionately increased in the case of a subdivision or the Warrant Price shall be proportionately increased and the number of Shares issuable hereunder shall be proportionately decreased in the case of a combination.

     (c) Stock Dividends and Other Distributions. If the Company at any time while this Warrant is outstanding and unexpired shall pay a dividend or make a distribution to all of its stockholders with respect to its Common Stock payable in Common Stock, then the Warrant Price shall be adjusted, from and after the date of determination of stockholders entitled to receive such dividend or distribution, to that price determined by multiplying the Warrant Price in effect immediately prior to such date of determination by a fraction (A) the numerator of which shall be the total number of shares of Common Stock outstanding immediately prior to such dividend or distribution, and (B) the denominator of which shall be the total number of shares of Common Stock outstanding immediately after such dividend or distribution.

     (d) Adjustment of Number of Shares. Upon each adjustment in the Warrant Price pursuant to Sections 4(a) through (c) above, the number of Shares purchasable hereunder shall be adjusted, to the nearest whole share, to the product obtained by multiplying the number of Shares purchasable immediately prior to such adjustment in the Warrant Price by a fraction, the numerator of which shall be the Warrant Price immediately prior to such adjustment and the denominator of which shall be the Warrant Price immediately thereafter.

     (e) Warrant Price Adjustments; Issuance of Common Stock at less than Warrant Price. If the Company, at any time while this Warrant is outstanding and on or prior to June 30, 2005, shall consummate the issue or sale, or is, in accordance with any of the subsections of this Section 4(e), deemed to have consummated the issue or sale, any Additional Shares of Common Stock (as defined below) for a consideration per share less than the Warrant Price in effect immediately prior to the time of such issue or sale, then and in each such case (a “Trigger Issuance”) the then-existing Warrant Price, shall be reduced, as of the close of business on the effective date of the Trigger Issuance, to a price equal to the lowest price paid per share for such Common Stock. If no Trigger Issuance occurs, the then-existing Warrant Price as of the close of business on June 30, 2005 shall equal, as may be adjusted pursuant to Sections 4(a) through (c) above, the lesser of $3.85 and the average closing selling price of a share of Company common stock traded on the Nasdaq National Market, as quoted in The Wall Street Journal, over

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the 15-day period ending on June 30, 2005. For purposes of this subsection (e), “Additional Shares of Common Stock” shall mean all shares of Common Stock issued by the Company, or deemed to be issued pursuant to this subsection (e), in a private placement for the primary purpose of raising capital for the Company, other than Excluded Issuances (as defined in subsection (f) below). For purposes of this subsection (e), the following subsections (e)(l) to (e)(6) shall also be applicable:

          (1) Issuance of Rights or Options. In case at any time the Company shall in any manner grant (directly and not by assumption in a merger or otherwise) any warrants or other rights to subscribe for or to purchase, or any options for the purchase of, Common Stock or any stock or security convertible into or exchangeable for Common Stock (such warrants, rights or options being called “Options” and such convertible or exchangeable stock or securities being called “Convertible Securities”) whether or not such Options or the right to convert or exchange any such Convertible Securities are immediately exercisable, and the price per share for which Common Stock is issuable upon the exercise of such Options or upon the conversion or exchange of such Convertible Securities (determined by dividing (i) the sum (which sum shall constitute the applicable consideration) of (x) the total amount, if any, received or receivable by the Company as consideration for the granting of such Options, plus (y) the aggregate amount of additional consideration payable to the Company upon the exercise of all such Options, plus (z), in the case of such Options which relate to Convertible Securities, the aggregate amount of additional consideration, if any, payable upon the issue or sale of such Convertible Securities and upon the conversion or exchange thereof, by (ii) the total maximum number of shares of Common Stock issuable upon the exercise of such Options or upon the conversion or exchange of all such Convertible Securities issuable upon the exercise of such Options) shall be less than the Warrant Price in effect immediately prior to the time of the granting of such Options, then the total number of shares of Common Stock issuable upon the exercise of such Options or upon conversion or exchange of the total amount of such Convertible Securities issuable upon the exercise of such Options shall be deemed to have been issued for such price per share as of the date of granting of such Options or the issuance of such Convertible Securities. Except as otherwise provided in subsection 4(e)(3), no adjustment of the Warrant Price shall be made upon the actual issue of such Common Stock or of such Convertible Securities upon exercise of such Options or upon the actual issue of such Common Stock upon conversion or exchange of such Convertible Securities.

          (2) Issuance of Convertible Securities. In case the Company shall in any manner issue (directly and not by assumption in a merger or otherwise) or sell any Convertible Securities, whether or not the rights to exchange or convert any such Convertible Securities are immediately exercisable, and the price per share for which Common Stock is issuable upon such conversion or exchange (determined by dividing (i) the sum (which sum shall constitute the applicable consideration) of (x) the total amount received or receivable by the Company as consideration for the issue or sale of such Convertible Securities, plus (y) the aggregate amount of additional consideration, if any, payable to the Company upon the conversion or exchange thereof, by (ii) the total number of shares of Common Stock issuable upon the conversion or exchange of all such

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Convertible Securities) shall be less than the Warrant Price in effect immediately prior to the time of such issue or sale, then the total maximum number of shares of Common Stock issuable upon conversion or exchange of all such Convertible Securities shall be deemed to have been issued for such price per share as of the date of the issue or sale of such Convertible Securities, provided that (a) except as otherwise provided in subsection 4(e)(3), no adjustment of the Warrant Price shall be made upon the actual issuance of such Common Stock upon conversion or exchange of such Convertible Securities and (b) no further adjustment of the Warrant Price shall be made by reason of the issue or sale of Convertible Securities upon exercise of any Options to purchase any such Convertible Securities for which adjustments of the Warrant Price have been made pursuant to the other provisions of subsection 4(e).

          (3) Change in Option Price or Conversion Rate. Upon the happening of any of the following events, namely, if the purchase price provided for in any Option referred to in subsection 4(e)(l) hereof, the additional consideration, if any, payable upon the conversion or exchange of any Convertible Securities referred to in subsections 4(e)(l) or 4(e)(2), or the rate at which Convertible Securities referred to in subsections 4(e)(l) or 4(e)(2) are convertible into or exchangeable for Common Stock shall change at any time (including, but not limited to, changes under or by reason of provisions designed to protect against dilution), the Warrant Price in effect at the time of such event shall forthwith be readjusted to the Warrant Price which would have been in effect at such time had such Options or Convertible Securities still outstanding provided for such changed purchase price, additional consideration or conversion rate, as the case may be, at the time initially granted, issued or sold. On the termination of any Option for which any adjustment was made pursuant to this subsection 4(e) or any right to convert or exchange Convertible Securities for which any adjustment was made pursuant to this subsection 4(e) (including without limitation upon the redemption or purchase for consideration of such Convertible Securities by the Company), the Warrant Price then in effect hereunder shall forthwith be changed to the Warrant Price which would have been in effect at the time of such termination had such Option or Convertible Securities, to the extent outstanding immediately prior to such termination, never been issued.

          (4) Stock Dividends. Subject to the provisions of this Section 4(e), in case the Company shall declare a dividend or make any other distribution upon any stock of the Company (other than the Common Stock) payable in Common Stock, Options or Convertible Securities, then any Common Stock, Options or Convertible Securities, as the case may be, issuable in payment of such dividend or distribution shall be deemed to have been issued or sold without consideration.

          (5) Consideration for Stock. In case any shares of Common Stock, Options or Convertible Securities shall be issued or sold for cash, the consideration received therefore shall be deemed to be the gross amount received by the Company therefor, before deduction therefrom of any expenses incurred or any underwriting commissions or concessions paid or allowed by the Company in connection therewith. In case any shares of Common Stock, Options or Convertible Securities shall be issued or sold for a consideration other than cash, the amount of the consideration other than cash

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received by the Company shall be deemed to be the fair value of such consideration as determined in good faith by the Board of Directors of the Company, before deduction of any expenses incurred or any underwriting commissions or concessions paid or allowed by the Company in connection therewith. In case any Options shall be issued in connection with the issue and sale of other securities of the Company, together comprising one integral transaction in which no specific consideration is allocated to such Options by the parties thereto, such Options shall be deemed to have been issued for such consideration as determined in good faith by the Board of Directors of the Company.

          (6) Record Date. In case the Company shall take a record of the holders of its Common Stock for the purpose of entitling them (i) to receive a dividend or other distribution payable in Common Stock, Options or Convertible Securities or (ii) to subscribe for or purchase Common Stock, Options or Convertible Securities, then such record date shall be deemed to be the date of the issue or sale of the shares of Common Stock deemed to have been issued or sold upon the declaration of such dividend or the making of such other distribution or the date of the granting of such right of subscription or purchase, as the case may be.

     (f) Excluded Issuances. “Excluded Issuances” shall mean shares of Common Stock issued or issuable: (i) upon the conversion of shares of Preferred Stock; (ii) pursuant to the acquisition of another corporation or entity by the Company by way of merger, purchase of all or substantially all of the assets of the corporation, stock for stock exchange or other reorganization or recapitalization or pursuant to a joint venture agreement approved by the Board of Directors of the Company; (iii) to directors or employees of, or consultants or other service providers to, the Company under a stock option or other equity incentive plan or agreement approved by and in a manner determined by the Board of Directors (including restricted stock grants to directors, employees or consultants); (iv) upon the closing of any public offering of the Company’s securities; (v) by reason of a dividend, stock split, split-up or other distribution on shares of Common Stock for which adjustment is otherwise made pursuant to Section 4; (vi) stock or options or warrants to purchase capital stock, issued to financial institutions, strategic partners or lessors in connection with any commercial credit arrangement, equipment financing, strategic partnership or similar transaction; (vii) shares of Common Stock issued upon the exercise, exchange or conversion of Options or Convertible Securities outstanding as of the date hereof; (viii) shares of Common Stock issued or issuable in connection with any settlement of any action, suit, proceeding or litigation; (ix) shares of Common Stock issued or issuable in connection with any sponsored laboratory or clinical research or development, strategic collaboration, or marketing agreement, or any license of any data, product, intellectual property, or technology, or any other similar agreement, license or strategic partnership approved by the Board of Directors; and (x) shares of Common Stock issued or issuable to suppliers or third party service providers in connection with the provision of any goods or services pursuant to a transaction approved by the Board of Directors.

           5. Notice of Adjustments. Whenever the Warrant Price or the number of Shares purchasable hereunder shall be adjusted pursuant to Section 4 hereof, the Company shall

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make a certificate signed by its chief executive officer, chief financial officer or any vice president setting forth, in reasonable detail, the event requiring the adjustment, the amount of the adjustment, the method by which such adjustment was calculated, and the Warrant Price and the number of Shares purchasable hereunder after giving effect to such adjustment, and shall cause copies of such certificate to be mailed (without regard to Section 13 hereof, by first class mail, postage prepaid) to the holder of this Warrant at such holder’s last known address.

           6.      Fractional Shares. No fractional shares of Common Stock will be issued in connection with any exercise hereunder, but in lieu of such fractional shares the Company shall make a cash payment therefor based on the fair market value of the Common Stock on the date of exercise as reasonably determined in good faith by the Company’s Board of Directors.

           7.      Compliance with Securities Act; Disposition of Warrant or Shares of Common Stock.

     (a)      Compliance with Securities Act. The holder of this Warrant, by acceptance hereof, agrees that this Warrant, and the Shares to be issued upon exercise hereof are being acquired for investment and that such holder will not offer, sell or otherwise dispose of this Warrant, or any Shares except under circumstances which will not result in a violation of the Securities Act of 1933, as amended (the “Act”) or any applicable state securities laws. Upon exercise of this Warrant, unless the Shares being acquired are registered under the Act and any applicable state securities laws or an exemption from such registration is available, the holder hereof shall confirm in writing that the Shares so purchased are being acquired for investment and not with a view toward distribution or resale in violation of the Act and shall confirm such other matters related thereto as may be reasonably requested by the Company. This Warrant and all Shares issued upon exercise of this Warrant (unless registered under the Act and any applicable state securities laws) shall be stamped or imprinted with a legend in substantially the following form:

     Said legend shall be removed by the Company, upon the request of a holder, at such time as the restrictions on the transfer of the applicable security shall have terminated. In addition, in

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connection with the issuance of this Warrant, the holder specifically represents to the Company by acceptance of this Warrant as follows:

          (1)      The holder is aware of the Company’s business affairs and financial condition, and has acquired information about the Company sufficient to reach an informed and knowledgeable decision to acquire this Warrant. The holder is acquiring this Warrant for its own account for investment purposes only and not with a view to, or for the resale in connection with, any “distribution” thereof in violation of the Act.

          (2)      The holder understands that this Warrant has not been registered under the Act in reliance upon a specific exemption therefrom, which exemption depends upon, among other things, the bona fide nature of the holder’s investment intent as expressed herein.

          (3)      The holder further understands that this Warrant must be held indefinitely unless subsequently registered under the Act and qualified under any applicable state securities laws, or unless exemptions from registration and qualification are otherwise available. The holder is aware of the provisions of Rule 144, promulgated under the Act.

          (4)      The holder is an “accredited investor” as such term is defined in Rule 501 of Regulation D promulgated under the Act.

     (b) Disposition of Warrant or Shares. With respect to any offer, sale or other disposition of this Warrant or any Shares acquired pursuant to the exercise of this Warrant prior to registration of such Warrant or Shares, the holder hereof agrees to give written notice to the Company prior thereto, describing briefly the manner thereof, together with a written opinion of such holder’s counsel, or other evidence satisfactory to the Company, to the effect that such offer, sale or other disposition may be effected without registration or qualification (under the Act as then in effect or any federal or state securities law then in effect) of this Warrant or the Shares and indicating whether or not under the Act certificates for this Warrant or the Shares to be sold or otherwise disposed of require any restrictive legend as to applicable restrictions on transferability in order to ensure compliance with such law. Upon receiving such written notice and reasonably satisfactory opinion or other evidence, the Company, as promptly as practicable but no later than fifteen (15) days after receipt of the written notice, shall notify such holder that such holder may sell or otherwise dispose of this Warrant or such Shares, all in accordance with the terms of the notice delivered to the Company. If a determination has been made pursuant to this Section 7(b) that the opinion of counsel for the holder or other evidence is not reasonably satisfactory to the Company, the Company shall so notify the holder promptly with details thereof after such determination has been made. Notwithstanding the foregoing, this Warrant or such Shares may, as to such federal laws, be offered, sold or otherwise disposed of in accordance with Rule 144 or 144A under the Act, provided that the Company shall have been furnished with such information as the Company may reasonably request to provide a reasonable assurance that the provisions of Rule 144 or 144A have been satisfied. Each certificate representing this Warrant or the Shares thus transferred (except a transfer pursuant to Rule 144) shall bear a legend as to

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the applicable restrictions on transferability in order to ensure compliance with such laws, unless in the aforesaid opinion of counsel for the holder, such legend is not required in order to ensure compliance with such laws. The Company may issue stop transfer instructions to its transfer agent in connection with such restrictions.

     (c)      Applicability of Restrictions. Neither any restrictions of any legend described in this Warrant nor the requirements of Section 7(b) above shall apply to any transfer or grant of a security interest in, this Warrant (or the shares of Common Stock obtainable upon exercise thereof) or any part hereof (i) to a partner of the holder if the holder is a partnership or to a member of the holder if the holder is a limited liability company, (ii) to a partnership of which the holder is a partner or a limited liability company of which the holder is a member, or (iii) to any affiliate of the holder if the holder is a corporation; provided, however, in any such transfer, if applicable, the transferee shall on the Company’s request agree in writing to be bound by the terms of this Warrant as if an original holder hereof.

           8. Rights as Stockholders. No holder of this Warrant, as such, shall be entitled to vote or receive dividends or be deemed the holder of Common Stock or any other securities which may at any time be issuable on the exercise hereof for any purpose, nor shall anything contained herein be construed to confer upon the holder of this Warrant, as such, any of the rights of a stockholder of the Company or any right to vote for the election of directors or upon any matter submitted to stockholders at any meeting thereof, or to receive notice of meetings, or to receive dividends or subscription rights or otherwise until this Warrant shall have been exercised and the Shares purchasable upon the exercise hereof shall have become deliverable, as provided herein.

           9. Registration Rights. The Company grants registration rights to the holder of this Warrant for any shares of Common Stock of the Company obtained upon exercise hereof as set forth in that certain Warrant Exchange Agreement, dated as of even date herewith, by and among the Company and the other parties thereto.

           10. Additional Rights.

           10.1. Mergers. The Company shall provide the holder of this Warrant with at least twenty (20) days’ written notice prior to the closing thereof of the terms and conditions of any of the following transactions: (i) the sale, lease, exchange, conveyance or other disposition of all or substantially all of the Company’s property or business or (ii) its merger into or consolidation with any other corporation (other than a wholly-owned subsidiary of the Company), or (iii) any transaction (including a merger or other reorganization) or series of related transactions, in which more than 50% of the voting power of the Company is disposed of.

           10.2. Right to Convert Warrant into Stock: Net Issuance.

     (a)      Right to Convert. In addition to and without limiting the rights of the holder under the terms of this Warrant, the holder shall have the right to convert this Warrant or any portion thereof (the “Conversion Right”) into shares of Common Stock as provided in this Section 10.2 at any time or from time to time during the term of this

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X = B — A
          Y

     Where: X = the number of shares of Common Stock that may be issued to the holder.

Y = the fair market value of one share of Common Stock.

A = the aggregate Warrant Price of the specified number of Converted Warrant Shares
immediately prior to the exercise of the Conversion Right (i.e., the number of
Converted Warrant Shares multiplied by the Warrant Price).

B = the aggregate fair market value of the specified number of Converted Warrant
Shares (i.e., the number of Converted Warrant Shares multiplied by the fair market
value of one Converted Warrant Shares).

     No fractional shares shall be issuable upon exercise of the Conversion Right, and, if the number of shares to be issued determined in accordance with the foregoing formula is other than a whole number, the Company shall pay to the holder an amount in cash equal to the fair market value of the resulting fractional share on the Conversion Date (as hereinafter defined). For purposes of Section 9 of this Warrant, shares issued pursuant to the Conversion Right shall be treated as if they were issued upon the exercise of this Warrant.

     (b)      Method of Exercise. The Conversion Right may be exercised by the holder by the surrender of this Warrant at the principal office of the Company together with a written statement (which may be in the form of Exhibit A-1 or Exhibit A-2 hereto) specifying that the holder thereby intends to exercise the Conversion Right and indicating the number of shares subject to this Warrant which are being surrendered (referred to in Section 10.2(a) hereof as the Converted Warrant Shares) in exercise of the Conversion Right. Such conversion shall be effective upon receipt by the Company of this Warrant together with the aforesaid written statement, or on such later date as is specified therein (the “Conversion Date”), and, at the election of the holder hereof, may be made contingent upon the closing of the sale of the Company’s Common Stock to the public in a public offering pursuant to a registration statement under the Act (a “Public Offering”). Certificates for the shares issuable upon exercise of the Conversion Right and, if applicable, a new warrant evidencing the balance of the shares remaining subject to this Warrant, shall be issued as of the Conversion Date and shall be delivered to the holder within thirty (30) days following the Conversion Date.

     (c)      Determination of Fair Market Value. For purposes of this Section 10.2, “fair market value” of a share of Common Stock as of a particular date (the “Determination Date”) shall mean:

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          (i)      If the Conversion Right is exercised in connection with and contingent upon a Public Offering, and if the Company’s Registration Statement relating to such Public Offering (“Registration Statement”) has been declared effective by the Securities and Exchange Commission, then the initial “Price to Public” specified in the final prospectus with respect to such offering.

          (ii)      If the Conversion Right is not exercised in connection with and contingent upon a Public Offering, then as follows:

     (A)      If traded on a securities exchange, the fair market value of the Common Stock shall be deemed to be the average of the closing prices of the Common Stock on such exchange over the five trading days immediately prior to the Determination Date;

     (B)      If traded on the Nasdaq Stock Market or other over-the-counter system, the fair market value of the Common Stock shall be deemed to be the average of the closing bid prices of the Common Stock over the five trading days immediately prior to the Determination Date; and

     (C)      If there is no public market for the Common Stock, then fair market value shall be reasonably determined by the Company’s Board of Directors.

     If closing prices or closing bid prices are no longer reported by a securities exchange or other trading system, the closing price or closing bid price shall be that which is reported by such securities exchange or other trading system at 4:00 p.m. New York City time on the applicable trading day.

           11. Representations and Warranties. The Company represents and warrants to the holder of this Warrant as follows:

     (a)      This Warrant has been duly authorized and executed by the Company and is a valid and binding obligation of the Company enforceable in accordance with its terms, subject to laws of general application relating to bankruptcy, insolvency, moratorium, reorganization and the relief of debtors and the rules of law or principles at equity governing specific performance, injunctive relief and other equitable remedies (regardless of whether enforcement is sought in equity or at law);

     (b)      The Shares have been duly authorized and reserved for issuance by the Company and, when issued in accordance with the terms hereof will be validly issued, fully paid and non-assessable;

     (c)      The execution and delivery of this Warrant are not, and the issuance of the Shares upon exercise of this Warrant in accordance with the terms hereof will not be, inconsistent with the Company’s certificate of incorporation or by-laws, do not and will not contravene any law, governmental rule or regulation, judgment or order applicable to

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the Company, and do not and will not conflict with or contravene any provision of, or constitute a default under, any material indenture, mortgage, contract or other instrument of which the Company is a party or by which it is bound or require the consent or approval of, the giving of notice to, the registration or filing with or the taking of any action in respect of or by, any Federal, state or local government authority or agency or other person, except for the filing of notices pursuant to federal and state securities laws, which filings will be effected by the time required thereby; and

     (d)      There are no actions, suits, audits, investigations or proceedings pending or, to the knowledge of the Company, threatened against the Company in any court or before any governmental commission, board or authority which, if adversely determined, will have a material adverse effect on the ability of the Company to perform its obligations under this Warrant.

           12.      Modification and Waiver. This Warrant and any provision hereof may be changed, waived, discharged or terminated only by an instrument in writing signed by the party against which enforcement of the same is sought.

           13.      Notices. Any notice, request, communication or other document required or permitted to be given or delivered to the holder hereof or the Company shall be delivered, or shall be sent by certified or registered mail, postage prepaid, to each such holder at its address as shown on the books of the Company or to the Company at the address indicated therefor on the signature page of this Warrant.

           14.      Binding Effect on Successors. This Warrant shall be binding upon any corporation succeeding the Company by merger, consolidation or acquisition of all or substantially all of the Company’s assets, and all of the obligations of the Company relating to the Shares issuable upon the exercise or conversion of this Warrant shall survive the exercise, conversion and termination of this Warrant and all of the covenants and agreements of the Company shall inure to the benefit of the successors and assigns of the holder hereof.

           15.      Lost Warrants or Stock Certificates. The Company covenants to the holder hereof that, upon receipt of evidence reasonably satisfactory to the Company of the loss, theft, destruction or mutilation of this Warrant or any stock certificate and, in the case of any such loss, theft or destruction, upon receipt of an indemnity reasonably satisfactory to the Company, or in the case of any such mutilation upon surrender and cancellation of such Warrant or stock certificate, the Company will make and deliver a new Warrant or stock certificate, of like tenor, in lieu of the lost, stolen, destroyed or mutilated Warrant or stock certificate.

           16.      Descriptive Headings. The descriptive headings of the several paragraphs of this Warrant are inserted for convenience only and do not constitute a part of this Warrant. The language in this Warrant shall be construed as to its fair meaning without regard to which party drafted this Warrant.

           17.      Governing Law. This Warrant shall be construed and enforced in accordance with, and the rights of the parties shall be governed by, the laws of the State of Delaware.

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           18.      Survival of Representations, Warranties and Agreements. All representations and warranties of the Company and the holder hereof contained herein shall survive the Date of Grant, the exercise or conversion of this Warrant (or any part hereof) or the termination or expiration of rights hereunder. All agreements of the Company and the holder hereof contained herein shall survive indefinitely until, by their respective terms, they are no longer operative.

           19.      Remedies. In case any one or more of the covenants and agreements contained in this Warrant shall have been breached, the holders hereof (in the case of a breach by the Company), or the Company (in the case of a breach by a holder), may proceed to protect and enforce their or its rights either by suit in equity and/or by action at law, including, but not limited to, an action for damages as a result of any such breach and/or an action for specific performance of any such covenant or agreement contained in this Warrant.

           20.      No Impairment of Rights. The Company will not, by amendment of its certificate of incorporation or through any other means, avoid or seek to avoid the observance or performance of any of the terms of this Warrant, but will at all times in good faith assist in the carrying out of all such terms and in the taking of all such action as may be necessary or appropriate in order to protect the rights of the holder of this Warrant against impairment.

           21.      Severability. Whenever possible, each provision of this Warrant shall be interpreted in such a manner as to be valid, legal and enforceable under all applicable laws and regulations. If, however, any provision of this Warrant shall be invalid, illegal or unenforceable under any such law or regulation in any jurisdiction, it shall, as to such jurisdiction, be deemed modified to conform to the minimum requirements of such law or regulation, or, if for any reason it is not deemed to be so modified, it shall be invalid, illegal or unenforceable only to the extent of such invalidity, illegality or limitation on enforceability without affecting the remaining provisions of this Warrant or the validity, legality or enforceability of such provision in any other jurisdiction.

           22.      Entire Agreement; Modification. This Warrant constitutes the entire agreement between the parties pertaining to the subject matter contained in it and supersedes all prior and contemporaneous agreements, representations, and undertakings of the parties, whether oral or written, with respect to such subject matter.

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     IN WITNESS WHEREOF, the parties have executed this Warrant as of the date first written above.

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Exhibit A-1

Notice of Exercise

_____________________________________
                                 (Signature)

Dated: _______________________________

Exhibit A-2

Notice of Exercise

Dated: ____________________