Exhibit 10.23
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                                AMENDMENT NO. 1
                                ---------------

                                      TO
                            KIRIN-AMEN. INC. /AMEN
                            ----------------------
                     G-CSF UNITED STATES LICENSE AGREEMENT
                     -------------------------------------


          THIS AMENDMENT N0. 1 ("Amendment No. 1") TO THAT CERTAIN KIRIN-AMGEN,
INC./AMGEN G-CSF UNITED STATES LICENSE AGREEMENT ("License Agreement"), is made
and entered into this 20th day of October, 1988, by and between AMGEN INC., a
Delaware corporation ("Amgen"), and KIRIN-AMGEN, INC., a California corporation
("Corporation").

                                R E C I T A L S

          A.   Amgen and Corporation have previously executed that certain
License Agreement regarding G-CSF.

          B.   The parties desire to incorporate certain changes into the
 License Agreement pursuant to this Amendment No. 1.

          NOW, THEREFORE, it is agreed as follows:

1.        Article I, Section 1.08 at page 3 of the License Agreement is hereby
deleted and the following substituted in lieu thereof:

               "Sales Value. 'Sales Value' shall mean the amount billed by Amgen
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          or an affiliate from the sale for commercial use of G-CSF Products to
          independent third parties less the following amounts included in the
          billed amount: (i) discounts, including cash discounts, or rebates
          actually allowed or granted from the billed amount, (ii) credits or
          allowances actually granted upon claims or returns regardless of the
          party requesting the return, (iii) freight charges paid for delivery,
          and (iv) taxes or other government charges levied on or measured by
          the billed amount whether absorbed by the billing or the billed
          party."

2.        Except to the extent as provided herein, the provisions of the License
Agreement are hereby ratified and confirmed in all respects.


         IN WITNESS WHEREOF, the undersigned have caused this Amendment No. 1 to
be executed as of the first day written above.

                                   AMGEN INC.,
                                   a Delaware corporation


                                   By   /s/ George B. Rathmann
                                      George B. Rathmann, President
                                                              "Amgen"




                                   KIRIN-AMGEN, INC.,
                                   a California corporation


                                   By   /s/ Yashushi Yamamoto
                                        Yasushi Yamamoto, Chairman
                                                              "Corporation"

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