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                                                                  EXHIBIT 10.18


                             CONSULTING CONTRACT

     This document will confirm the agreement between GalaGen Inc.
("GalaGen"), located at 4001 Lexington Avenue North, Arden Hills, Minnesota,
55126 and Stanley Falkow, Ph.D. ("Senior Consultant"), located at 8 Longspur,
Portola Valley, CA 94025, with respect to GalaGen's engagement of Senior
Consultant as an independent consultant.   Specifically, the parties agree as
follows:

1.0  SCOPE OF WORK

     1.1  Senior Consultant will be available to provide to GalaGen such
services related to review of scientific programs, as more fully set forth in
the attached Schedule A.  Those services will be performed in accordance with
the terms and specifications, directions and instructions issued by GalaGen
in written form to Senior Consultant.  Those directions and instructions
shall constitute the only authorization for Senior Consultant to take any
action or spend any money.

     1.2  Senior Consultant is an independent consultant performing services
on a contract basis for a variety of persons and entities.  As an independent
consultant of GalaGen, Senior Consultant is not authorized to act on behalf
of GalaGen as its agent or as an employee.  Senior Consultant shall not have
the right or power to bind GalaGen to any contracts or agreements with any
third party, nor shall Senior Consultant have the right or power to direct
any operations of GalaGen.  The relationship created by this Agreement is
that of a contract for services and nothing herein contained is intended to
nor shall it create the relationship of employment, partnership, joint
venture or agency.

2.0  PAYMENT

     GalaGen will pay Senior Consultant for services under this Agreement in
accordance with the payment schedule set forth in the attached Schedule B.

3.0  CONFIDENTIALITY

     3.1  In performing services on behalf of GalaGen, Senior Consultant will
be exposed to and will be required to use certain "Confidential Information"
(as hereinafter defined) of GalaGen.  Senior Consultant agrees not to use or
disclose, directly or indirectly, such Confidential Information for the
benefit of any person or organization other than GalaGen, either during or
after the term of this Agreement, for as long as such information retains the
characteristics of Confidential Information.  Senior Consultant agrees not to
disregard its obligations of confidence hereunder by using any trade secret
or other Confidential Information to guide Senior Consultant in a search of
publications or other publicly available information, selecting a series of
items of knowledge from unconnected sources and fitting them together in
order to support a claim that Senior Consultant did not violate any
obligations set forth in this Agreement.

     3.2  "Confidential Information" means information not generally known,
including trade secrets about GalaGen's methods, processes and products,
including but not limited to information relating to such matters as research
and development, analysis, manufacturing methods, processes, techniques,
formulations, data, chemical composition of materials, applications for
particular technologies or chemical compounds, materials or designs, vendor
names, customer lists, management systems, and sales and


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marketing plans.  All information disclosed to Senior Consultant or to which
Senior Consultant has access during the term of this Agreement which Senior
Consultant has a reasonable basis to believe is Confidential Information or
which is treated by GalaGen as Confidential Information shall be presumed to
be Confidential Information.

     3.3  Promptly upon the expiration or termination of this Agreement, or
upon the request of GalaGen, Senior Consultant shall return to GalaGen all
documents and tangible items provided to Senior Consultant or created by
Senior Consultant for use in connection with services to be rendered
hereunder, including without limitation all Confidential Information,
together with all copies, recordings, abstracts, notes, reproductions of any
kind made from or about the documents and tangible items or the information
contained therein.

4.0  RIGHTS AND DATA

     4.1  All works of authorship, documents and tangible items prepared for
or submitted to GalaGen by Senior Consultant under this Agreement shall
belong exclusively to GalaGen and shall be deemed to be works made for hire
(the "Deliverable Items").  To the extent that any of the Deliverable Items
may not, by operation of law, be works made for hire, Senior Consultant
hereby assigns to GalaGen the ownership of copyright work in the Deliverable
Items, and GalaGen shall have the right to obtain and hold in its own name
any trademark, copyright, or mask work registration, and any other
registrations and similar protection which may be available in the
Deliverable Items.  Senior Consultant agrees to give GalaGen or its designees
all assistance reasonably required to perfect such rights.

     4.2  To the extent that any pre-existing materials are contained in the
Deliverable Items, Senior Consultant grants to GalaGen an irrevocable,
nonexclusive, worldwide, royalty-free license to (a) use, execute, reproduce,
display, perform, distribute (internally or externally) copies of, and
prepare derivative works based upon, such pre-existing materials and
derivative works thereof; and (b) authorize others to do any, some or all of
the foregoing.

     4.3  In providing services and preparing Deliverable Items hereunder,
Senior Consultant understands that GalaGen does not wish to receive from
Senior Consultant any information which may be considered confidential and/or
proprietary to Senior Consultant or to any third party.  Senior Consultant
represents and warrants that any information disclosed to GalaGen by Senior
Consultant hereunder is not confidential and/or proprietary to Senior
Consultant or to any third party.

     4.4  Senior Consultant represents and warrants the originality of the
Deliverable Items and that no portion of the Deliverable Items, or their use
or distribution, violates or is protected by any copyright or similar right
of any third party.

     4.5  No license or right is granted to Senior Consultant, either
expressly or by implication, estoppel or otherwise, to use, execute, publish,
reproduce, prepare derivative works based upon, distribute copies, publicly
display, or perform the Deliverable Items either during or after the term of
this Agreement.

5.0  INVENTIONS

     5.1  Senior Consultant agrees that all "Inventions" (as hereinafter
defined) made during the term of this Agreement shall be the exclusive
property of GalaGen unless released to Senior Consultant in writing by the
President of GalaGen.

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     5.2  "Invention" shall mean any invention, discovery, work of
authorship, improvement, concept or idea, whether patentable or not
(including those which may be subject to trademark, copyright registration),
including but not limited to machines, devices, processes, methods,
techniques and formulae, generated, conceived or reduced to practice by
Senior Consultant, either alone or in conjunction with others, during or
after working hours; provided, that either the conception or reduction to
practice occurs during the term of this Agreement and in connection with the
performance of services hereunder.

     5.3  Senior Consultant shall (a) promptly and fully disclose and
describe all Inventions in writing to an officer of GalaGen or anyone else
designated by GalaGen (such disclosure shall include, if requested, a
detailed report of the procedure employed and the results achieved by Senior
Consultant); and (b) give GalaGen all assistance GalaGen requires to perfect,
protect and use its rights to Inventions, including but not limited to
signing all documents, doing all things and supplying all information that
GalaGen may deem necessary or desirable to (i) transfer or record the
transfer to GalaGen of the entire right, title and interest of Senior
Consultant and/or Senior Consultant's employees in Inventions, and (ii)
enable GalaGen to obtain patent, copyright, or trademark protection for the
Inventions anywhere in the world.

     5.4  The obligations of this paragraph 5.0 shall continue beyond the
expiration or termination of this Agreement with respect to Inventions which
Senior Consultant and/or Senior Consultant's employees conceive or make
during the term of this Agreement.  For purposes of this agreement, any
Invention relating to the existing or reasonably foreseeable business
interest of GalaGen for which Senior Consultant and/or Senior Consultant's
employees file a patent application or any trademark, copyright or mask work
registration within one (1) year after the termination of this Agreement
shall be presumed to be an Invention which was conceived during the term of
this Agreement, subject to proof to the contrary.

NOTICE:  To the extent that Minnesota Statute 181.78 applies, Senior
Consultant is hereby notified that this Agreement does not apply to an
Invention for which no equipment, supplies, facility or trade secret
information of GalaGen was used, and which was developed entirely on Senior
Consultant's own and/or Senior Consultant's employee's time and (a) which
does not relate (i) directly to the business of GalaGen, or (ii) to GalaGen's
actual demonstrably anticipated research or development; or (b) which does
not result from any work performed by Senior Consultant and/or Senior
Consultant's employees for GalaGen.

6.0  SENIOR CONSULTANT'S EMPLOYEES NOT DEEMED GALAGEN'S

     Personnel supplied by Senior Consultant will be deemed employees of
Senior Consultant and will not for any purpose be considered employees or
agents of GalaGen.  Senior Consultant assumes full responsibility for the
actions of such personnel while performing services pursuant to any
directions or instructions of GalaGen issued hereunder, and shall be solely
responsible for their supervision, daily direction and control, payment of
salary (including, withholding of income taxes and social security), worker's
compensation, disability benefits and the like, and shall indemnify and hold
GalaGen harmless for any and all such expenses, liabilities and obligations.

7.0  TERM, TERMINATION AND CANCELLATION

     7.1  This Agreement shall commence on December 4, 1996 and shall expire on
December 3, 1997. Thereafter, this Agreement shall be renewable for successive
one year periods upon the mutual written agreement of the parties.

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     7.2  Notwithstanding anything contained herein to the contrary, either
party may terminate this Agreement at any time upon five (5) days prior
written notice to the other party.

8.0  GENERAL PROVISIONS

     8.1  Senior Consultant's rights and obligations of paragraphs 3.0, 4.0
and 5.0 are unconditional and shall survive and continue after any expiration
or termination of the Agreement, and shall bind the parties and their legal
representatives, successors, heirs and assigns.

     8.2  In addition to other relief provided by law, Senior Consultant
agrees that GalaGen may enforce the covenants contained in the Agreement by
an injunction issued against Senior Consultant and any person concerned, it
being understood that both damages and injunction shall be proper modes of
relief and are not to be considered as alternative remedies.

     8.3  In the event any provision of this Agreement is held unenforceable
by a court of competent jurisdiction, that provision shall be severed and
shall not affect the validity or enforceability of the remaining provisions.
In the event that any provision of this Agreement is held to be overbroad,
such provision shall be deemed amended to narrow its application to the
extent necessary to render such provision enforceable according to applicable
law.

     8.4  This Agreement shall be governed by and construed in accordance
with the internal laws (and not the laws of conflicts) of the State of
Minnesota.

     8.5  This instrument sets forth the entire understanding and agreement
of the parties as to the subject matter of this Agreement.  This Agreement
may be changed or modified only by an agreement in writing signed by the
party against whom enforcement of any change or modification is sought.

     8.6  This Agreement may be transferred by GalaGen to its successors and
assigns.  Neither Senior Consultant nor GalaGen may assign or transfer,
voluntarily or involuntarily, by operation of law or otherwise, any of their
respective rights or obligations under this Agreement.

     8.7  The waiver by GalaGen of a breach of any provision of this
Agreement by Senior Consultant shall not operate or be construed as a waiver
of any other or subsequent breach by Senior Consultant.

     8.8  All notices, requests and other communications hereunder shall be
in writing, and shall be deemed to have been duly given when mailed or
delivered in person to the other party at the address first set forth above,
or at such other address as either party may hereafter designate by written
notice to the other party.

     8.9  The various headings in this Agreement are for convenience only and
shall not affect the meaning or interpretation of this Agreement or any
provisions hereof.

     8.10 Senior Consultant represents that he will use his best efforts to
successfully pursue GalaGen's objectives herein stated.  However, Senior
Consultant does not guarantee that his best efforts will be successful.

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     8.11 GalaGen hereby indemnifies Senior Consultant against any and all
third parties for any claims against Senior Consultant arising out of the use
of GalaGen biopharmaceuticals or related products.

     8.12 Under no circumstances shall Senior Consultant be liable for any
special, indirect, incidental or consequential damages of any kind or nature
whatsoever arising under or in any way related to this Agreement or the
transactions contemplated herein.  Senior Consultant's liability arising out
of this contract are limited to any fees received in consideration of this
contract, unless Senior Consultant's liability arises from gross negligence
or willful misconduct on Senior Consultant's part.

     If the foregoing accurately sets forth the understanding between GalaGen
and Stanley Falkow, Ph.D., please so indicate by signing in the space
provided below and returning one fully signed copy of this letter to GalaGen.

Read and agreed to this 15 day of January, 1997

By: /s/ Robert A. Hoerr
    ----------------------------------------
    Robert A. Hoerr, M.D., Ph.D.
    President and Chief Executive Officer

Read and agreed to this 15 day of January, 1997

By: /s/ Stanley Falkow
    ----------------------------------------
    Stanley Falkow, Ph.D.


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                                  SCHEDULE A

   1. Services to be performed by Senior Consultant will include consulting
with respect to scientific programs and development projects, identification
of scientific personnel for potential hire or consulting projects,
participation in ad hoc scientific advisory panels organized by the Company,
assessment of technology for in-licensing and other projects related to
scientific programs of the Company.

   2. It is expressly understood and agreed that for all purposes, including,
but not limited to workers' compensation insurance, unemployment insurance,
FICA, and federal and state tax withholding, any agent or employee of Senior
Consultant performing work under this Agreement shall be deemed as an
independent consultant and not an employee of GalaGen.  Neither Senior
Consultant nor any agent or employee of Senior Consultant shall be entitled
to any benefits which GalaGen provides to its employees.



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                                 SCHEDULE B

   In consideration for the services performed by Senior Consultant under
this Agreement, and as approved by the Board of Directors, the Senior
Consultant will receive an option to purchase 50,000 shares of the Company's
Common Stock at an exercise price per share equal to the fair market value of
a share of Common Stock on the date of approval of such grant by the Board.
Receipt of the option by Senior Consultant is subject to and expressly
conditioned upon receipt of approval by the Board.  The option would become
exercisable with respect to 33 1/3 percent of the number of shares covered
thereby on each of the first three anniversaries of the date of grant.  The
option would expire upon the earlier of five years and three months after the
date of grant or 90 days after the termination by the Company of the
Consulting Contract of which this Schedule is a part. The option would have
such other terms as are set forth in a written option agreement to be
prepared by and which is satisfactory to the Company.

   GalaGen shall reimburse Senior Consultant for reasonable out of pocket
expenses, materials and other related costs incurred in connection with
performance of services under this Agreement, including travel expenses (at
coach fare), materials, and other costs incurred at the request of GalaGen.
These costs are to be approved in advance, supported by adequate receipts,
and sent to GalaGen on a monthly basis, or more frequently, in conjunction
with the services invoice described above.  All expense reimbursements will
be made in cash.


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