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                                                                    Exhibit 10.6

                              EMPLOYMENT AGREEMENT

         This EMPLOYMENT AGREEMENT, dated as of July 1, 1997 between
BioNebraska, Inc., a corporation incorporated and existing under the laws of
Delaware (formerly Nebraska) and having its office at 3820 NW 46th Street in
Lincoln, Nebraska (hereinafter referred to as "Company"), and CHRISTOPHER S.
HICKEY, residing at 4473 Scarsdale Place, Boulder, Colorado 80301 (hereinafter
referred to as the "Manager").

         WHEREAS the Company desires to employ the Manager at its Lincoln,
Nebraska facilities as Vice President, Production Management and, as such, as a
member of its management group; and the Manager desires to be so employed:

         NOW THEREFORE, in consideration of the foregoing and of the mutual
promises hereinafter set forth, the parties hereto agree as follows:

1.       EMPLOYMENT: POWERS AND DUTIES.

         The Company hereby employs the Manager as its Vice President,
Production Management and its Manager of Industrial Manufacturing pursuant to
the provisions of this Agreement. The Manager shall be responsible for the
conception, design, equipment selection, start-up and operations of pilot and
commercial production facilities for the larger scale application of the
Company's peptide production technologies and the development of
manufacturing systems and protocols to be used in these facilities. The
Manager shall perform services in such capacity for the Company and for any
of its affiliates or subsidiaries with such authority and with such powers
and duties as may be prescribed or assigned to him from time to time by the
Board of Directors of the Company and by the Chairman of the Board and the
President of the Company. In performing his services hereunder, he shall
report to the Senior Vice President of Research and Development.

2.       EXCLUSIVITY.

         During the term of his employment hereunder, the Manager will devote
his best efforts, energy, skill and resources to his duties hereunder and to the
affairs and interests of the Company and its affiliates and subsidiaries and
will not, without the approval of the Board of Directors of the Company or the
Chairman of the Board or the President, actively engage in consulting for or in
the conduct of any other business in the chemical, biotech or medical fields.

3.       DIRECT COMPENSATION

         During his employment hereunder, the Manager shall receive salary at
the annual rate of ninety-five thousand dollars ($95,000), to be paid in equal
monthly installments after required tax and other deductions are made from such
installments. At the end of each calendar year under this

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Agreement, the performance of the Manager will be reviewed. In the event that
his performance and contributions to the Company have been in accordance with
or exceeding expectations for the particular year, as determined by the
Chairman of the Board and President, it is anticipated that the Manager will
receive a positive adjustment to his salary level over that obtained in the
previous year.

         In addition, assuming the Company's situation permits, the Board of
Directors of the Company may establish an appropriate incentive program to
provide additional incentive compensation to the Manager in the event certain
goals, to be mutually agreed upon by the Company and the Manager, are met during
a particular calendar year of his service hereunder. The Manager may also
receive additional compensation from the Company's subsidiaries and affiliates.

4.       ADDITIONAL BENEFITS.

         (A) The Manager shall be provided with such health, sickness, accident,
hospitalization, disability, life and other insurance benefits as are generally
provided under the Company's and/or its affiliates' group policies. This will
include life insurance coverage of at least $100,000 for the Manager.

         The Company will also reimburse to the Manager any costs incurred by
him for maintenance of COBRA health insurance coverage after July 1st of this
year in the event and to the extent coverage for him under the Company's health
plan is delayed after that date.

         (B) When and if instituted, the Manager shall be provided with such
savings and retirement plan benefits as may be provided in general for employees
under the Company's plans, as adopted or amended from time to time, based on his
compensation received from the Company from time to time. The Company has
established a 401(K) Plan for retirement savings for all employees including the
Manager. Initial Company contributions to this Plan are expected to be small or
non-existent until funding of the Company permits (as determined in the sole
discretion of the Board of Directors) significant contributions and to be modest
thereafter until the Company becomes substantially profitable in its operations.

5.       LONG-TERM STOCK OPTION INCENTIVES.

         The Manager shall be allotted an incentive stock option under the
Company's 1993 Stock Plan, as amended, covering a total of forty thousand
(40,000) shares of the Company's Common Stock. This option will be vested and
become exercisable thereafter in three equal annual installments over the three
years, beginning as of a date which is one year after the date of this
Agreement. The option price will be $7.00 per share being the f air market value
of the shares at the time the options are granted, as determined by the Board of
Directors.

       The Manager will be eligible for participation in additional stock plans
of the Company if and to the extent that the Board of Directors at the relevant
time, in it its sole discretion, shall consider that the work and contributions
of the Manager merit such participation.


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6.       EXPENSES.

         The Company shall reimburse to the Manager all reasonable travel,
hotel, entertainment and other out-of-pocket expenses which he may from time to
time incur in the course of carrying out his duties for the Company and any of
its affiliates or subsidiaries.

         The Company shall reimburse the Manager's reasonable costs of moving
his household to Lincoln, such expenses being estimated to be in the range of
$5,000. The Company will reimburse the reasonable costs for the Manager and his
wife to make up to three trips to Lincoln from Boulder to locate housing. Also,
the Company will pay the reasonable cost of a furnished apartment during the
time (estimated not to exceed three months) it may take the Manager to sell his
current house and relocate to Lincoln. In the event the Manager is unable to
locate permanent housing during that three month period (or in the event his
current house is sold and his new house in Lincoln is not available for
occupancy), the Company will reimburse the Manager for costs of obtaining
appropriate storage for his household effects for a period of up to three
months. Finally, the Company will reimburse to the Manager any IRS income tax
payment effect he may incur relative to the Company's reimbursement to him of
reasonable expenses of moving to Lincoln pursuant to this Agreement after he has
taken whatever business deductions are available to him under the Internal
Revenue Code for such expenses.

7.       NON-COMPETITION.

         (A) During the term of his employment hereunder, and for a two-year
period thereafter, the Manager agrees that, unless he obtains written consent
from the Company covering a particular planned competitive activity, (and in the
event of termination of the Manager's employment hereunder for any reason the
Company shall in its discretion continue to pay compensation to the Manager
after such termination equal to at least one half of the total level of salary
received during the last year prior to the termination of the Manager's
employment hereunder) the Manager shall not directly or indirectly engage in,
consult for, be employed by or finance any business activity that is competitive
with the businesses which are being conducted by the Company or by any affiliate
or subsidiary or customer of the Company. For purposes of the foregoing,
activities other than the production and sale of regulatory peptide hormones,
such as GRF, GLP-1 and PTH and their analogs and mimics, would not be considered
competitive to the Company's business. Specifically, the production and sale of
large proteins or small chemical molecules which are used for treating the same
indications that the Company and its customers would expect to treat with
regulatory peptide hormones will not be considered competitive. The foregoing
notwithstanding, the Company shall have no obligation, in the event of
termination of employment, to pay any continuing compensation.

         (B) In no event will the Manager at any time during or within a period
which is two years after termination of his employment hereunder, without
receiving the Company's prior written consent:


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         (i)      preempt, divert, disrupt or otherwise interfere with any
                  business relationship of the Company, or of any of its
                  affiliates or subsidiaries, with any of the clients, customers
                  or business contacts of the Company or of any of its
                  affiliates or subsidiaries; or

         (ii)     solicit for employment for his own or another's benefit (as
                  employee, partner, consultant, independent contractor or
                  otherwise) any person who has been employed by the Company or
                  by any affiliate or subsidiary of the Company.

8.       INTELLECTUAL PROPERTY RIGHTS.

         (A) As between the Company or any of its affiliates or subsidiaries, as
the case may be, and the Manager, all products, know-how, methods, processes,
discoveries, materials, ideas, strategies, creations, inventions and properties
pertaining or relating to the businesses of the Company, or of any affiliate or
subsidiary of the Company, which the Manager may create by himself or with
others or to which he may become exposed, whether or not developed or invented
by the Manager and whether or not developed or discovered during regular working
hours, shall be the sole and absolute property of the Company or the particular
affiliate or subsidiary, for any and all purposes. The Manager shall not claim
to have, under this Agreement or otherwise, any right, title or interest of any
kind or nature in any of the foregoing.

         (B) The Manager acknowledges that in the course of his employment
hereunder he will make use of, acquire and add to confidential information of
the Company and its affiliates and subsidiaries of a special and unique nature
and value relating to such matters as trade secrets, products, technical
systems, processes and procedures, know-how, inventions, manuals, confidential
reports, plans, properties, strategies and customer business. The Manager agrees
that with respect to any of the foregoing, during and following the term hereof,
for so long as same remains confidential (and beyond should loss of
confidentiality be caused by the Manager), he will not, for any purposes (unless
otherwise agreed to by the Company in writing) divulge or disclose any of such
information or let others use such information for any purpose other than for
the benefit of the Company or its affiliate or subsidiaries, as the case may be.

9.       TERM OF EMPLOYMENT.

         The Manager's employment shall continue indefinitely hereunder, unless
and until terminated by either party upon delivery of six months' prior written
notice of termination to the other party.

         Notwithstanding the foregoing, the Company shall be entitled by notice
in writing to the Manager to terminate forthwith his employment with the Company
under this Agreement if he shall have engaged in any willful misconduct or
misconduct involving negligence or commit any material breach of his obligations
to the Company hereunder.


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10.      VACATION.

         The Manager shall be entitled to fifteen business days of vacation in
each calendar year.

11.      RETURN OF DOCUMENTS.

         The Manager shall promptly, upon the termination of his employment with
the Company hereunder, deliver to the Company all office copies of reports,
memoranda, accounts, laboratory and other notebooks, and correspondence which
may have been prepared by him or have come into his possession or control in the
course of his employment hereunder.

12.      NOTICES.

         All notices hereunder shall be in writing and delivered personally or
by registered or certified mail which shall be addressed to the Company at its
principal office and to the Manager at the address stated in the first paragraph
of this Agreement, or in either case at such other address as shall be
designated in writing by the party to whom the notice is to be sent. Any such
communication so sent by mail shall be deemed made or given upon mailing.

13.      MISCELLANEOUS.

         The BioNebraska Employee Handbook has been furnished to the Manager and
shall form part of this Agreement. The Manager agrees to comply with operational
rules of the Company as adopted from time to time and set forth in the Company's
Handbook. This Agreement constitutes the entire agreement of the parties hereto
relating to the subject matter hereof and there are no written or oral terms or
representations made by either party other than those contained herein. All of
the terms and provisions of this Agreement shall be binding upon and shall inure
to the benefit of and be enforceable by and against the parties to this
Agreement and their respective heirs, executors, and successors in interest. The
provisions of Sections 7, 8, 11, 13 and 14 hereunder shall survive the
termination of this Agreement to the extent necessary to accomplish the purposes
of the provisions in such Sections.

14.      GOVERNING LAW.

         This Agreement shall be governed and construed in accordance with the
laws of Nebraska.


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         IN WITNESS WHEREOF, the Company has caused this Agreement to be
executed by its duly authorized officer and the Manager has executed this
Agreement as of the date first written above.

                                         BIONEBRASKA, INC.



                                         By/s/ Thomas R. Coolidge
                                           -------------------------------------
                                              Thomas R. Coolidge
                                              Chairman of the Board and C.E.O.



/s/ Christopher S. Hickey
---------------------------------
CHRISTOPHER S. HICKEY
         (The Manager)


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