**Exhibit10.39**

*****TextOmitted and Filed Separatelywith the Securities and Exchange Commission.Confidential Treatment RequestedUnder 17 C.F.R. Sections 200.80(b)(4)and 240.24b-2.**

**FIFTH AMENDMENTTO THECOLLABORATIVE RESEARCH AND LICENSE AGREEMENT**

**THIS FIFTH AMENDMENTTO THE COLLABORATIVE RESEARCH AND LICENSE AGREEMENT**(the ***“Fifth Amendment”***) isentered into as of October 29, 2006 (the ***“Fifth Amendment Effective Date***”) by andbetween **SENOMYX, INC.**(***“Senomyx”***),a Delaware corporation, having a principal place of business at 11099 NorthTorrey Pines Road, La Jolla, California 92037, and **KRAFT FOODS GLOBAL, INC.**,a Delaware corporation (***“Kraft”***)having offices at 801 Waukegan Road, Glenview, IL 60025.

**WHEREAS,**Senomyx and Kraft entered into that certain Collaborative Research and LicenseAgreement dated as of December 6, 2000, as amended by that certain FirstAmendment dated May 2, 2002, that certain Second Amendment dated April 29, 2005,that certain Third Amendment dated July 29, 2005, that certain Fourth Amendmentdated December 9, 2005 and that certain Amended and Restated Fourth Amendmentdated December 9, 2005 (collectively, the ***“Agreement”***);

 **WHEREAS,** within [...***...]days of the Fifth Amendment Effective Date, Senomyx shall submit to Kraft a writtenreport regarding [...***...], which the Steering Committee has determined to bereasonable within the meaning of Section 3.1.1(C)(ii), thereby completing Senomyx’sobligations under the [...***...] Phase (capitalized terms used but not otherwisedefined in this Fifth Amendment shall have the meanings given such terms in theAgreement); and

**WHEREAS,**in recognition of Senomyx’s completion of its obligations under the [...***...], Senomyxand Kraft wish to amend the Agreement to shift the remaining research funding fromthe [...***...] Phase to the [...***...] Phase;

**NOW, THEREFORE,** in consideration of theforegoing premises and of the covenants, representations and agreements setforth below, the parties hereby agree to amend the Agreement as follows:

**1.****                                     **Senomyx,within [...***...] days of the Fifth Amendment Effective date, shall submit toKraft a written report regarding [...***...]. Upon receipt thereof by Kraft, theparties agree that Senomyx’s obligations under the [...***...] Phase shall be completedpursuant to Section 3.1.1(C) of the Agreement. The parties’ rights and obligations with respect to the [...***...] Phase ofthe Collaborative Program under Sections 3, 9 and 10 of the Agreement willcontinue only with respect to [...***...].

**2.****                                     **Pursuantto Section 9.2(B) of the Agreement, Kraft will pay Senomyx a milestone payment of[...***...] within [...***...] days of the Fifth Amendment Effective Date.

**3.****                                     **Section3.1.1(B) of the Agreement is hereby amended and restated as follows:

*****Confidential Treatment Requested**

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“During the Collaborative Period which will continuethrough [...***...] for the [...***...] Phase, Kraft will evaluate [...***...] and mayselect [...***...] for further development by notifying Senomyx of such selectionin writing on or before expiration of the Collaborative Period.  Upon such notification, [...***...] will become a[...***...] Compound.”

**4.****                                     **Section9.1 of the Agreement is hereby modified such that all research funding from the[...***...] Phase is shifted to the [...***...] Phase as of the Fifth AmendmentEffective Date.  Accordingly, beginningon December 9, 2006 and through the end of the December 8, 2007, Kraft will paySenomyx at an annual rate of [...***...] for the [...***...] Phase.  From December 9, 2007, Kraft will pay Senomyxat an annual rate of [...***...] through the end of the Collaborative Period forthe [...***...] Phase.  These payments willbe made [...***...] and on an [...***...], provided that, with respect to the change infunding rate, payments for any period at a particular funding rate for lessthan one [...***...] of the Collaborative Period will be based on the pro rataportion of the [...***...] installment based on the actual number of days in such [...***...]at the applicable funding rate. Kraft shall have the right to terminate the [...***...]Phase of the Agreement by providing Senomyx with thirty (30) days advancewritten notice prior to the second anniversary date (December 9, 2007) of theEffective Date of the Restated Fourth Amendment (the “No Go Notification”).

**5.****                                     **Exceptas specifically amended by this Fifth Amendment, the terms and conditions ofthe Agreement shall remain in full force and effect.

**6.****                                     **ThisFifth Amendment will be governed by the laws of the State of California, assuch laws are applied to contracts entered into and to be performed entirelywithin such State.

**7.****                                     **ThisFifth Amendment may be executed in two or more counterparts, each of whichshall be deemed an original, but all of which together shall constitute one andthe same instrument.

**IN WITNESS WHEREOF**, the parties, through their authorized officers, have executed this Fifth Amendment as of the Fifth Amendment Effective Date.
| **SENOMYX, INC.**                            | ** **       | **KRAFT FOODS  GLOBAL, INC.**                       |
|----------------------------------------------|------------------|-----------------------------------------------------|
| ** **                                   | ** **       | ** **                                          |
| By:                                          | /s/ Kent Snyder  |                                                | By: | /s/ Todd Abraham |
|                                         |             |                                                |
| Name: Kent Snyder                            |             | Name: Todd Abraham                                  |
| Title: President and Chief Executive Officer |             | Title: VP Global Research & Technology Strategy |
|                                         |             |                                                |
| Date:                                        | October 31, 2006 |                                                | Date: | November 6, 2006 |

 

*****Confidential Treatment Requested**

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