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                                                                    EXHIBIT 10.2

                               AMENDMENT NO. 3 TO
                             NOTE PURCHASE AGREEMENT

                  THIS AMENDMENT NO. 3 (the "AMENDMENT"), dated as of March 5,
2003, is by and between INTERLEUKIN GENETICS, INC., a Delaware corporation (the
"COMPANY"), and PYXIS INNOVATIONS INC., a Delaware corporation ("PYXIS").

                  The Company and Pyxis are parties to a Note Purchase Agreement
dated as of October 23, 2002, as amended November 13, 2002 and January 28, 2003
(the "AGREEMENT"). Capitalized terms not otherwise defined in this Amendment
shall have the meanings given to them in the Agreement.

                  The parties agree as follows:

1.       The Recitals of the Agreement are revised to reflect the following
         developments since the Initial Closing:

                  Pyxis has purchased, and the Company has sold and issued to
                  Pyxis, a promissory note in a principal amount of $500,000 on
                  each of the following dates: October 23, 2002, November 14,
                  2002, December 16, 2002, and January 28, 2003 (the "EXISTING
                  NOTES").

                  On March 5, 2003, the Company and Pyxis entered into Stock
                  Purchase Agreement (the "STOCK PURCHASE AGREEMENT") and
                  various agreements referenced therein (collectively, the
                  "AFFILIATION AGREEMENTS"). Pursuant to Section 2.5 of the
                  Stock Purchase Agreement, Pyxis has agreed to extend further
                  credit to the Company to (i) expand its research partnerships
                  (the "RESEARCH LOANS"), and (ii) refinance the Company's
                  bridge financing loans coming due in August 2003 (the
                  "REFINANCING LOAN"). In addition, pursuant to Section 2.6 of
                  the Stock Purchase Agreement, the Company and Pyxis have
                  agreed to amend and restate the terms of the Existing Notes.

2.       The following new Sections shall be added immediately following Section
         2.2 of the Agreement:

                           2.2A     REFINANCING LOAN. At any time before July
                  31, 2003 (at the discretion of Pyxis), Pyxis hereby agrees to
                  purchase, and the Company hereby agrees to sell and issue to
                  Pyxis, a Note in a principal amount of $525,000 plus interest
                  then due under the terms of the promissory notes issued by the
                  Company in its August 2002 bridge financing. Subject to the
                  terms and conditions of this Agreement, the closing of this
                  purchase (also a "Subsequent Closing") will take place five
                  business days following the Company's written request to Pyxis
                  to make such loan.

                           2.2B     STRATEGIC LOANS. At any time prior to March
                  5, 2005, Pyxis hereby agrees to purchase, and the Company
                  hereby agrees to sell and issue to Pyxis, one or more Notes,
                  the aggregate principal amount of which shall not exceed
                  $1,500,000. Subject to the terms and conditions of this
                  Agreement, the closing of these purchases (each, a "Subsequent
                  Closing") will take place within five business days following
                  the Company's written request to Pyxis to make such loan;
                  provided that the Company shall not make such request until
                  after it
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                  has made a board approved payment of monies in connection with
                  the entry of a new or expanded strategic partnership or
                  research collaboration with one or more universities, health
                  organizations, and other third-parties in genomics.

                           2.2C     EXISTING NOTES. At the Closing under the
                  Stock Purchase Agreement, the Company and Pyxis shall amend
                  and restate each of the Existing Notes in the form described
                  in Section 2.2D, with maturity dates of December 31, 2007.

                           2.2D     FORM OF NOTE. The Notes for the Refinancing
                  Loan and the Research Loans, as well the amended and restated
                  Existing Notes, shall be in a form substantially similar to
                  the form of Note set forth on SCHEDULE 1. The term of the Note
                  shall be five years from the date of issuance. Interest shall
                  be prime plus 1%, paid quarterly.

3.       The phrase "in the aggregate principal amount of $500,000" is deleted
         from the second sentence of Section 2.3 of the Agreement. The following
         sentence is added as the final sentence: "For each Note, the "Purchase
         Price" shall be equal to 100% of the principal amount of such Note."

4.       Section 3.6 of the Agreement is hereby amended to insert the phrase
         "Except as contemplated by the Affiliation Agreements," at the
         beginning of the section, immediately prior to the words "Since
         December 31, 2001 . . . ".

5.       The following is added to the end of Section 5.1 of the Agreement:
         "Notwithstanding the previous sentence, use the proceeds from the sale
         of the Notes (i) in connection with the Refinancing Loan solely to pay
         off in full all of the promissory notes issued by the Company in its
         August 2002 bridge financing; and (ii) in connection with the Research
         Loans solely as a reimbursement of monies spent in furtherance of a new
         or expanded strategic partnership or research collaboration with one or
         more universities, health organizations, or other third-parties in
         genomics (provided that monies paid in connection with this
         partnership/collaboration shall have been first approved by the Board
         of Directors of the Company).

8.       Section 6.4 of the Agreement is hereby amended to insert the phrase
         "Except as provided in the Affiliation Agreements," at the beginning of
         the section, immediately prior to the words "Pay any dividends . . . ".

9.       Nothing in the Note Purchase Agreement, including Sections 7.1, 7.3 and
         7.4, shall be construed or interpreted as superceding any provisions in
         the Affiliation Agreements.

10.      Except as amended hereby, all of the terms and conditions of the
         Agreement shall remain in full force and effect. This Amendment shall
         be binding upon and inure to the benefit of the parties hereto and
         their respective successors and assigns.

                                      * * *


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                  This Amendment No. 3 to Note Purchase Agreement is signed as
of the date first written above.


                                         INTERLEUKIN GENETICS, INC

                                         By  /s/ Fenel M. Eloi
                                             -------------------------------
                                             Fenel M. Eloi
                                             Its Chief Financial Officer

                                         PYXIS INNOVATIONS INC.


                                         By  /s/ Beto Guajardo
                                             -------------------------------
                                             Beto Guajardo
                                             Its Duly Authorized Agent


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