FIRST AMENDMENT TO NOTE AND WARRANT PURCHASE AGREEMENT AND CONVERTIBLE PROMISSORY NOTE

Exhibit 10.17(c)

FIRST AMENDMENT

TO

NOTE AND WARRANT PURCHASE AGREEMENT

AND CONVERTIBLE PROMISSORY NOTE

This FIRST AMENDMENT TO NOTE AND WARRANT PURCHASE AGREEMENT AND CONVERTIBLE PROMISSORY NOTE (this “Amendment”) is made and entered into effective as of June 27, 2008 by and between HELIX BIOMEDIX, INC., a Delaware corporation (the “Company”), and RBFSC, Inc. (“RBFSC”).

RECITALS

WHEREAS, the Company and RBFSC entered into a Convertible Note and Warrant Purchase Agreement dated February 14, 2008 (the “Agreement”), pursuant to which the Company (i) issued to RBFSC a convertible promissory note (the “Note”) and (ii) is obligated to issue to RBFSC a warrant in substantially the form attached to the Agreement as Exhibit B on the terms and conditions set forth in the Agreement (the “Warrant”); and

WHEREAS, the Company and RBFSC wish to amend the Agreement and the Note as provided herein.

AGREEMENT

NOW, THEREFORE, in consideration of the premises, the mutual covenants of the parties hereinafter set forth and other good and valuable consideration, the receipt and sufficiency of which are hereby acknowledged, the parties hereto agree as follows:

1. The Maturity Date of the Note (as defined in the Note) shall be July 1, 2011.

2. Section 5 of the Note is hereby amended and restated in its entirety as follows:

“5. Conversion .

(a) Automatic Conversion upon Financing . Upon the closing (or first in a series of closings) of the next equity financing in which Company sells shares of its equity securities (the “ Equity Securities ”) for an aggregate consideration of at least $7,500,000 (excluding the aggregate principal and accrued interest due on this Note) (the “ Equity Financing ”), the principal and accrued interest due on this Note shall automatically be converted into shares of the Equity Securities as set forth in Section 5(d) below. The conversion shall be deemed to have occurred as of the date of such closing or the date of the first closing in a series of closings. As a condition precedent (which may be waived by the Company) to conversion of this Note as provided for in this Section 5(a), the Holder will be required to execute the definitive Stock Purchase Agreement and such other agreements prepared in connection with the Equity Financing. The number of shares of Equity Securities into which this Note shall be automatically converted shall be determined by dividing the principal and accrued interest due on this Note as of the date of conversion by an amount equal to the lesser of (i) the per share price of the Equity Securities issued and sold in the Equity Financing and (ii) $1.00.

(b) Automatic Conversion upon Financing . Upon the closing of a sale of substantially all of the Company’s assets or a merger or consolidation of the Company in which the Company’s stockholders will hold, in the aggregate, less than 50% of the voting power of the combined entity (a “ Change of Control ”), the principal and accrued interest due on this Note shall automatically be converted into shares of the Company’s Common Stock as set forth in Section 5(d) below. The conversion shall be deemed to have occurred as of the date of such closing. The number of shares of Common Stock into which this Note shall be automatically converted shall be determined by dividing the principal and accrued interest due on this Note as of the date of conversion by an amount equal to the lesser of (i) the per share price attributed to the Company’s Common Stock in connection with such transaction and (ii) $1.00.

(c) Voluntary Conversion at Maturity Date . At and as of the Maturity Date, to the extent this Note is still outstanding and has not otherwise been converted or repaid in full, the Holder will have the option, in its sole discretion, to convert this Note into shares of the Company’s Common Stock. The number of shares of Common Stock into which this Note may be voluntarily converted shall be determined by dividing the principal and accrued interest due on this Note as of the date of conversion by $1.00.

(d) Issuance of Securities on Conversion . As soon as practicable after conversion of this Note, the Company, at its expense, will cause to be issued in the name of and delivered to the Holder a certificate or certificates representing the number of fully paid and nonassessable shares of the Equity Securities or Common Stock (as applicable) to which Holder shall be entitled upon such conversion. No fractional shares will be issued upon conversion of this Note.

(e) Termination of Rights . All rights with respect to this Note shall terminate upon conversion hereof in accordance with this Section 5, whether or not this Note has been surrendered. Notwithstanding the foregoing, the Holder agrees to surrender this Note to Company for cancellation as soon as is practicable following conversion of this Note.”

3. The form of Warrant attached to the Agreement as Exhibit B is hereby amended and restated in its entirety in the form attached to this Amendment (the “Restated Warrant”).

4. Upon the execution of this Amendment by both parties, the Company shall promptly issue to RBFSC the Restated Warrant.

5. The parties hereto hereby acknowledge the continuing effect of the Agreement and the Note except as specifically modified by this Amendment.

IN WITNESS WHEREOF, the parties hereto have executed this Amendment as of the day and year first above written.

RESTATED WARRANT

(see attached)

THIS WARRANT AND THE SECURITIES ISSUABLE UPON THE EXERCISE HEREOF HAVE NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE “ACT”), OR ANY STATE SECURITIES LAWS. THEY MAY NOT BE SOLD, OFFERED FOR SALE, PLEDGED, HYPOTHECATED OR OTHERWISE TRANSFERRED IN THE ABSENCE OF A REGISTRATION STATEMENT IN EFFECT WITH RESPECT TO THE SECURITIES UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS OR UNLESS (i) SOLD PURSUANT TO AN EXEMPTION FROM REGISTRATION UNDER SUCH ACT AND APPLICABLE STATE SECURITIES LAWS AND (ii) AT THE OPTION OF THE COMPANY, AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE COMPANY THAT SUCH REGISTRATION IS NOT REQUIRED HAS BEEN DELIVERED TO THE COMPANY.

WARRANT FOR THE

PURCHASE OF SHARES OF COMMON STOCK

OF

HELIX BIOMEDIX, INC.

THIS CERTIFIES THAT, for valuable consideration, the undersigned, together with his successors and permitted assigns (the “Holder”) is entitled to purchase, subject to the terms set forth below, up to 750,000 shares of duly authorized, validly issued, fully paid and nonassessable shares of common stock, $0.001 par value per share (the “Common Stock”), of Helix BioMedix, Inc., a Delaware corporation (the “Company”).

1. Exercise of Warrant . The terms and conditions upon which this Warrant may be exercised, and the Common Stock covered hereby (the “Warrant Stock”) may be purchased, are as follows:

(a) Term . Subject to the terms hereof, the purchase right represented by this Warrant may be exercised in whole or in part, but not as to a fractional share of Warrant Stock, at any time and from time to time until July 1, 2013.

(b) Number of Shares . The number of shares of Common Stock for which this Warrant is initially exercisable is the amount set forth above the Holder’s signature and on page one of this Warrant, which number is subject to adjustment pursuant to Section 2 of this Warrant.

(c) Purchase Price . The per share purchase price for the shares of Common Stock to be issued upon exercise of this Warrant shall be equal to $1.00 per share (the “Warrant Price”).

(d) Method of Exercise . The exercise of the purchase rights evidenced by this Warrant shall be effected by (a) the surrender of the Warrant, together with a duly executed copy of the form of a subscription attached hereto, to the Company at its principal offices at 22118 20th Avenue SE, Suite 204, Bothell, WA 98021 (or such other office or agency of the Company as it may designate by notice in writing to the Holder at the address of the Holder appearing on the books of the Company) and (b) the delivery of the purchase price in an amount equal to the number of shares for which the purchase rights hereunder are being exercised multiplied by the Warrant Price, which amount may be paid by cashier’s check payable to the Company’s order or by wire transfer to the Company’s account. Each exercise of this Warrant shall be deemed to have been effected immediately prior to the close of business

on the day on which this Warrant shall have been surrendered to the Company together with the purchase price as provided herein or at such later date as may be specified in the executed form of subscription, and at such time the person or persons in whose name or names any certificate or certificates for shares of Common Stock shall be issuable upon such exercise as provided herein shall be deemed to have become the holder or holders of record thereof.

(e) Exercise by Exchange . In addition to and without limiting the rights of the Holder under the terms hereof, at the Holder’s option, and if approved by the Company, this Warrant may be exercised during the term specified under Section 1(a) by being exchanged in whole or in part prior to its expiration for a number of shares of Common Stock having an aggregate fair market value on the date of such exercise equal to the difference between (x) the fair market value of the number of shares of Common Stock subject to this Warrant designated by the Holder hereof on the date of the exercise and (y) the aggregate Warrant Price for such shares in effect at such times. The following formula illustrates how many shares would then be issued upon exercise pursuant to this Section 1(e):

Upon any such exercise, the number of shares of Common Stock purchasable upon exercise of this Warrant shall be reduced by such designated number of shares of Common Stock and, if a balance of purchasable shares of Common Stock remains after such exercise, the Company shall execute and deliver to the Holder hereof a new warrant for such balance of shares of Common Stock.

No payment to the Company of any cash or other consideration shall be required from the Holder of this Warrant in connection with any exercise of this Warrant by exchange pursuant to this Section 1(e). Such exchange shall be effective upon the date of receipt by the Company of the original Warrant surrendered for cancellation and a written request from the Holder hereof that the exchange pursuant to this section be made, or at such later date as may be specified in such request.

For the purposes of this Warrant, the “fair market value” of any number of shares of Common Stock shall mean:

(i) as long as the Common Stock is traded on the Over-The-Counter Bulletin Board or is traded on the American Stock Exchange (or equivalent recognized source of quotations), an amount equal to the average of the high and low reported trading prices of one share of such securities for the three (3) trading days prior to the surrender of this Warrant for exchange in accordance with the terms hereof; or

(ii) in all other cases, the fair value as determined in good faith by the Board of Directors of the Company and reasonably agreed to by the Holder.

(f) Issuance of Shares . As soon as reasonably practicable after each exercise of this Warrant, in whole or in part, the Company at its expense will cause to be issued in the name of and delivered to the Holder hereof or as such Holder (upon payment by such Holder of any applicable transfer taxes) may direct,

(i) a certificate or certificates for the number of duly authorized validly issued, fully paid and nonassessable shares of Common Stock to which such Holder shall be entitled upon such exercise, and

(ii) in case such exercise is in part only, a new warrant or warrants of like tenor, calling in the aggregate on the face or faces thereof for the number of shares of Common Stock (without giving effect to any adjustment thereof) to the number of such shares called for on the face of this Wa