EXHIBIT 10 (17) AMENDMENT NO. 1 TO AGREEMENT BETWEEN PHARMACIA CORPORATION (FORMERLY NAMED MONSANTO COMPANY) AND ROBERT B. SHAPIRO DATED DECEMBER 19, 1999 This Amendment No. 1 dated as of January 25, 2001 to the Agreement between Pharmacia Corporation...

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                                                                 EXHIBIT 10 (17)

                      AMENDMENT NO. 1 TO AGREEMENT BETWEEN
             PHARMACIA CORPORATION (FORMERLY NAMED MONSANTO COMPANY)
                  AND XXXXXX X. XXXXXXX DATED DECEMBER 19, 1999


         This Amendment No. 1 dated as of January 25, 2001 to the Agreement
between Pharmacia Corporation (formerly named Monsanto Company and referred to
herein as the "Company"), and Xxxxxx X. Xxxxxxx (the "Executive") dated as of
December 19, 1999 (the "Agreement") hereby amends the Agreement as follows:

         WHEREAS, the Company and the Executive entered into the Agreement for
the purpose, among other things, of providing for the Executive's performance of
certain services and for certain compensation and benefits to be provided to
Executive; and

         WHEREAS, the Agreement provides that the Company shall use its best
efforts to cause the Executive to be named Chairman of its Board of Directors
for a period of 18 months after the Effective Time (as defined in the
Agreement), and the Executive and the Company desire to terminate this provision
at the end of the Company's Board of Directors meeting on February 21, 2001; and

         WHEREAS, the Executive and the Company desire and intend that all other
provisions of the Agreement remain unchanged and in full force and effect for
the duration of the Agreement notwithstanding the fact that Executive will cease
being Chairman of the Board after February 21, 2001; and

         WHEREAS, the Board of Directors of the Company at a meeting duly called
and held on January 25, 2001 approved the proposed change in the Agreement and
otherwise confirmed the Agreement as the continuing agreement of the Company
notwithstanding the fact that Executive will cease being its Chairman of the
Board after February 21, 2001, and authorized and directed the Company's Chief
Executive Officer to execute such an amendment on behalf of the Company;

         NOW, THEREFORE, it is hereby agreed as follows:

         1.   The first sentence of paragraph 1(a) of the Agreement is hereby
              amended in its entirety to read as follows:

                  The Company shall use its best efforts to cause the Executive
                  to be named Chairman of its Board of Directors (the "Board")
                  for the period beginning at the Effective Time and ending
                  immediately after the meeting of the Board on February 21,
                  2001.

         2.   All other provisions of the Agreement shall remain in full force
              and effect without change notwithstanding the fact that Executive
              will cease being Chairman of the Board of the Company after
              February 21, 2001.


         IN WITNESS WHEREOF, the Executive and the Company have executed this
Amendment No. 1 as of the day and year first above written.

                                                --------------------------------
                                                Xxxxxx X. Xxxxxxx


                                                Pharmacia Corporation


                                            By:
                                                --------------------------------
                                                Xxxx Xxxxxx
                                                Chief Executive Officer