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                                                                   EXHIBIT 10.8



CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED SEPARATELY WITH
THE COMMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH RESPECT TO THE
OMITTED PORTION.



                                                                    Confidential


                    Amendment to Exclusive License Agreement


This letter agreement is being entered into for the purpose of amending that
certain Exclusive License Agreement ( the "License Agreement"), executed as of
August 3, 1993, between Gopal M. Nair, Ph.D. and BioNumerik Pharmaceuticals,
Inc. ("BNP").

In consideration of the foregoing and for other good and valuable consideration,
the receipt and sufficiency of which is hereby acknowledged, the parties hereby
agree as follows:

         1. Section 10.e.1) of the License Agreement is hereby amended so that
such section, as amended, will read in its entirety as follows:

         "BNP and/or its sublicensee(s) shall submit a request to initiate
         clinical trials (i.e. a U.S. IND application) necessary for government
         approval of a product, process, method or technology exclusively
         licensed from Nair within [**] after the execution date of the license
         in at least one country in North America."

         2. Section 1 of the License Agreement is hereby amended by (A) deleting
the fifth and sixth sentences of the third paragraph of Section 1 of the License
Agreement (which sentences begin with the language "In the event BNP sub
licenses..." and end with the language " .... to Nair according to the above
schedule") and (B) replacing such fifth and sixth sentences with new language
which shall read in its entirety as follows:

         "BNP shall have the right, following notice to Nair, to sublicense all
         or part of its rights to the Compounds (and/or all or part of its
         rights to products containing the Compounds and all other patent rights
         and other proprietary rights licensed under this Agreement ) to a third
         party or parties. In such event, BNP shall pay Nair [**]% of any
         up-front sublicensing payment amount that BNP receives from such
         sublicensee(s) and [**]% of all royalty and other payments that BNP
         receives from such sublicensee(s). Any sublicenses granted by BNP shall
         continue in full force and effect so long as Nair receives the
         sublicense payment amounts provided for above. Sales of Compounds
         and/or Products or other technology by sublicensees of BNP will not be
         subject to the royalty amounts on annual sales referred to in the first
         two paragraphs of this Section l ."



         [**] CERTAIN INFORMATION IN THIS EXHIBIT HAS BEEN OMITTED AND FILED
SEPARATELY WITH THE COMISSION. CONFIDENTIAL TREATMENT HAS BEEN REQUESTED WITH
RESPECT TO THE OMITTED PORTIONS.



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         3. All capitalized terms used in this letter agreement shall have the
same meaning as assigned to such terms in the License Agreement. Each party
hereto agrees to take such further actions and to sign such additional documents
as may be requested by the other party in order to further evidence or reflect
the intent of this agreement.

Except as amended hereby, all other terms and provisions of the License
Agreement will remain in full force and effect and continue in accordance with
their terms.

In Witness Whereof, the parties have executed this agreement as of August 23,
1996.


                                    BioNumerik Pharmaceuticals, Inc.



/s/ Madhavan G. Nair                By:      /s/ Frederick H. Hausheer
Gopal M. Nair, Ph.D.                         Frederick H. Hausheer M.D.
                                             Chairman and
                                             Chief Executive Officer


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                                                                    CONFIDENTIAL


                    AMENDMENT TO EXCLUSIVE LICENSE AGREEMENT


This amendment is being entered into for the purpose of amending that certain
Exclusive License Agreement between Gopal M. Nair, Ph.D. and BioNumerik
Pharmaceuticals, Inc. ("BNP"), executed as of August 3, 1993 and amended as of
August 23, 1996 (the "License Agreement").

In consideration of the foregoing and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereby
agree as follows:

         1. Section 10.e.2) of the License Agreement is hereby amended so that
such section, as amended, will read in its entirety as follows:

                  "BNP and/or its sublicensee(s) shall submit a request for
                  government approval (equivalent to a U.S. NDA or PLA) to
                  initiate commercial sales of a product, process, method or
                  technology exclusively licensed from Nair within 10 years
                  after the execution date of the license in at least one
                  country in any one of the Major Marketing Regions of the
                  World."

         2. All capitalized terms used in this amendment shall have the same
meaning as assigned to such terms in the License Agreement. Each party hereto
agrees to take such further actions and to sign such additional documents as may
be requested by the other party in order to further evidence or reflect the
intent of this agreement.

Except as amended hereby, all other terms and provisions of the License
Agreement will remain in full force and effect and continue in accordance with
their terms.

In Witness Whereof, the parties have executed this amendment as of the dates
indicated below.


                                            BioNumerik Pharmaceuticals, Inc.


/s/ Madhavan G. Nair                        /s/ Frederick H. Hausheer
Gopal M. Nair, Ph.D.                        Frederick H. Hausheer, M.D.
                                            Chairman and Chief Executive Officer

Nov. 19, 1998                               11/23/98
Date                                        Date