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                                                                   EXHIBIT 10.05

                               AMENDMENT NO. 2 TO
                             NOTE PURCHASE AGREEMENT

         THIS AMENDMENT NO. 2 (the "AMENDMENT"), dated as of January 28, 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 (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.       Recital C of the Agreement is hereby deleted in its entirety and
         replaced with the text of Recital C that is set forth as follows:

                           C. Pyxis wishes to purchase, and the Company wishes
                  to sell and issue to Pyxis, upon the terms and conditions
                  stated in this Agreement, on each of the date of this
                  Agreement, November 14, 2002, December 16, 2002, and January
                  28, 2003, a promissory note in a principal amount of $500,000
                  in the form attached as EXHIBIT A (each, a "NOTE" and
                  collectively, the "NOTES"); and

2.       Section 2.2 of the Agreement is hereby deleted in its entirety and
         replaced with the text of Section 2.2 that is set forth as follows:

                           2.2 SUBSEQUENT PURCHASES. Pyxis hereby agrees to
                  purchase, and the Company hereby agrees to sell and issue to
                  Pyxis, on each of November 14, 2002, December 16, 2002, and
                  January 28, 2003, a Note in the principal amount of $500,000.
                  The closing of the November 14, 2002 purchase, the closing of
                  the December 16 purchase, and the closing of the January 28,
                  2003 purchase, are each referred to as a "SUBSEQUENT CLOSING."

3.       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. 2 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/  Bert Crandell
                                                 -------------------------------

                                                   Its Duly Authorized Agent


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