THIS CONSULTING AGREEMENT, dated March 6, 2000 is between Dr. Ammon B.
Peck, Department of Pathology, University of Florida College of Medicine ("you")
and Ixion Biotechnology, Inc., a Delaware corporation with principal offices at
12085 Research Drive, Alachua, Florida 32615 ("we" or the "Company").

         WHEREAS, you have been performing consulting services for us pursuant
to a consulting agreement dated October 6, 1994, and

     WHEREAS, we propose that you continue to perform consulting services for
us, and

         WHEREAS, we understand you are willing to perform such services for us,
upon revised terms and conditions set forth below.

         NOW, THEREFORE, we agree with you as follows:

         1. You will perform such consulting services as we may request during
the term of this Agreement as Chief Scientist of the Company and as Chairman of
the Company's Scientific Advisory Board. You will be available to perform such
services at reasonable times during the term of this Agreement as may be
determined by you in your discretion taking into account your obligations as a
full-time professor in the Department of Pathology at the University of Florida
College of Medicine. In no event shall you be obligated to perform services
hereunder for a total of more than four days in any calendar month during the
term of this agreement.

         2. In full compensation for your services and agreements hereunder, we
will pay you at the rate of $50,000.00 per year. Should your services exceed the
48 days referred to above, an appropriate adjustment will be made in your
payments. In addition, we will reimburse you (as discussed below) for all
reasonable traveling and living expenses necessarily incurred by you while you
are away from your regular place of business or at our premises at our request
and are engaged in the performance of services for us under this Agreement. You
will submit invoices promptly showing any disbursements for reasonable and
necessary expenses incurred on this engagement.

     3. The manner in which you render services to us will be within your sole
control and discretion.

         4. You will observe our rules, policies, and regulations with respect
to conduct, scientific misconduct, and the health, safety, and protection of
persons and property, while on our premises. You will comply with all
governmental laws, ordinances, rules and regulations applicable to your services
hereunder, or to the performance thereof.


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         5. All of the following sections 5 and 6 are subject to your
obligations to the University of Florida under its patent policy (including the
University's policy respecting publication of the results of scientific
investigation). All inventions, improvements, discoveries, patent applications,
patents, trade secrets, know-how, biological material, data, reagents, or other
intellectual property, patentable or unpatentable ("invention"), which are made
or conceived by you during the term of this Agreement (i) relating to
Oxalobacter formigenes, oxalate, or oxalate-related disorders, (ii) relating to
islet progenitor/stem cells ("IPSCs"), or (iii) relating to any other invention,
provided rights thereto shall be waived or not owned by the University of
Florida, shall be our sole and exclusive property throughout the world. Promptly
upon conception of such invention, you will disclose it us, and we shall have
full power and authority to file and prosecute patent applications throughout
the world thereon and to procure and maintain patents thereon. You shall, at our
request and expense, execute documents and perform such acts as our counsel may
deem advisable, to confirm in us all right, title, and interest throughout the
world, in and to, such invention, discovery, or idea, and all patent
applications, patents, and copyrights thereon, and to enable and assist us in
procuring, maintaining, enforcing and defending patents, petty patents,
copyrights, and other applicable statutory protection throughout the world on
any such invention, discovery, or idea which may be patentable or copyrightable.

         6. All information and know-how which you in any way obtain from us and
all inventions which shall become our property pursuant to this Agreement, shall
be held secret and confidential by you and shall not be used or revealed by you
unless, until, and to the extent we shall consent thereto in writing, or such
information, know-how, inventions, discoveries, and ideas are generally
available to the public through no action or inaction of yours.

         7. You will not disclose to us any knowledge, information, inventions,
discoveries, or ideas which you possess under an obligation of secrecy to a
third party.

         8. You do not have any express or implied obligation to a third party
which in any way conflicts with any of your obligations under this Agreement,
except your obligations as an employee of the University of Florida, of which we
are aware.

         9. It is understood that we will have the royalty-free and unrestricted
right to use and disclose to third parties, any inventions disclosed to us by
you in the course of your services under this Agreement.

         10. All written information, drawings, documents and materials prepared
by you in the course of your service hereunder shall be our sole and exclusive
property, and will be delivered to us by you promptly after expiration or
termination of this Agreement, together with all written information, drawings,
documents and materials, if any, furnished by us to you in connection with your
services hereunder and not consumed by you in the performance of such services.

         11. You assume all risk and liability for loss of, or damage to, your
property, and for personal injury, sickness and/or disease, including death
resulting therefrom, sustained by you, if or where such loss or damage is
incurred or such injury, sickness, or disease is sustained, in connection with
your presence on our property and/or any services hereunder, unless caused by
our negligence or the negligence of our employees or agents.


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         12. During the term of this Agreement, you agree not to perform for a
third party any services which are in the field of this Agreement. During the
period of this Agreement, and for the two years thereafter, you will not,
directly or indirectly, engage in any business which is substantially
competitive with any business then actively being conducted by us, or
contemplated by us in the near future, nor will you consult with or advise any
such competitive business or otherwise, directly or indirectly, engage in any
activity which is substantially competitive with or in any way adversely affects
any material activity of ours.

         13. The term of this Agreement shall commence on the date first above
mentioned, and shall terminate a) on December 31, 2002, or b) upon thirty days
notice by either party, unless sooner terminated by your death, or in accordance
with the terms of this Agreement.

         14. The provisions of paragraphs 5, 6, 7, 9, 10, 11, and 16 shall
survive and continue after expiration or termination of this Agreement.

         15. Any assignment by you of this Agreement or of any of the rights or
obligations hereunder, without our written consent, shall be void. No
modifications of this Agreement or waiver of any of the terms or conditions
contained hereunder shall be binding unless in writing and signed by both
parties. This Agreement shall be governed by the laws of the State of Florida.

         16. We will have the sole and exclusive power to determine when we have
adequate resources available to pay your cash compensation, otherwise, such
compensation shall be deferred.

         If you agree to the foregoing, please indicate your acceptance thereof
by signing the enclosed duplicate copy of this Agreement and returning it to us.

                                               Very truly yours,

                                              Ixion Biotechnology, Inc.

                                               /s/Kimberly A. Ransey
                                              By -----------------------------
                                               Kimberly A. Ramsey
                                               Vice President and Controller

Accepted and Agreed

/s/ Ammon B. Peck Ph.D.
-----------------------
Ammon B. Peck, Ph.D.