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                                                                    Exhibit 10.2

                              EMPLOYMENT AGREEMENT


         Employment Agreement, dated as of July 1, 1993 between Bio-Nebraska,
Inc., a corporation incorporated and existing under the laws of Delaware
(formerly Nebraska) and having its office at 3940 Cornhusker Highway in Lincoln,
Nebraska (hereinafter referred to as "Company"), and THOMAS R. COOLIDGE,
residing at Beebe Hill Road, Falls Village, CT 06031 (hereinafter referred to as
the "Executive").

         WHEREAS the Company desires to employ the Executive as its Chairman of
the Board, member of the Company's Board of Directors and Chief Executive
Officer; and the Executive 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 Executive as its Chairman of the Board,
member of its Board of Directors and Chief Executive Officer pursuant to the
provisions of this Agreement. The Executive shall perform services in such
capacities 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 as may be
appropriately attributed to his service in the foregoing capacities by law and
custom.

2.       EXCLUSIVITY.

         During the term of his employment hereunder, the Executive 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 the Company, actively engage in
the conduct of any other business in the biotech or medical field.

3.       DIRECT COMPENSATION

         During the period from July 1 through December 31, 1993 he shall be
paid $120,000 in equal monthly installments after required deductions are made
from such installments. During the year, 1994, the Executive shall be paid
$175,000, also in equal monthly installments after required deductions are made.
At the end of the calendar year, 1994, the performance of the Executive shall be
reviewed. In the event that performance has been satisfactory as determined by
the Board of Directors of the Company, the Executive shall receive a substantial
positive adjustment to his compensation level over that obtaining in calendar,
1994 in order to reflect his contributions to the

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Company and to bring his compensation in line with other executives of
comparable position, accomplishment and potential. The Board of Directors of
the Company, in addition, shall establish an appropriate and substantial
incentive program to provide additional incentive compensation to the
Executive in the event certain goals, to be mutually agreed upon by the
Company and the Executive, are met during 1995. Thereafter, during the term
of this Agreement, the Company shall perform a similar review of the
Executive's performance annually and new incentive payments to be based on
new performance goals will be mutually determined for the subsequent year.
The Executive may also receive compensation from the Company's subsidiaries
and affiliates.

4.       ADDITIONAL BENEFITS.

         (A) The Executive shall be provided with health, accident,
hospitalization, disability, life and other insurance benefits as are generally
provided under the Company's and/or its affiliates group policies.

         (B) When and if instituted, the Executive 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.

         (C) The Executive may also receive certain special life insurance,
retirement and/or deferred compensation benefits, as mutually agreed upon by the
Company and the Executive from time to time.

5.       LONG-TERM INCENTIVES.

         The Executive shall be considered favorably for the receipt from time
to time of stock options under the Company's Stock Plan, as the same may be in
effect from time to time.

6.       EXPENSES.

         The Company shall reimburse to the Executive all reasonable travel,
hotel, entertainment and other out-of-pocket expenses as well as the reasonable
expenses of his office in Connecticut, 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.

7.       NON COMPETITION.

         The Executive agrees that during the term of his employment hereunder,
and for a one-year period thereafter (in the event the Company shall continue
compensation to the Executive after

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termination of employment equal to the total level received during the last
year prior to the Termination of this Agreement), the Executive shall not do
any of the following, without first receiving the Company's written consent:

                  (i)      Engage in, be employed by or finance any business
                           activity that is competitive with the business which
                           is being conducted by the Company or any affiliate or
                           subsidiary;

                  (ii)     Compete with, divert, disrupt or otherwise interfere
                           with any business relationship of the Company or any
                           affiliate or subsidiary with any of the clients,
                           customers or business contacts of the Company or any
                           affiliate or subsidiary; or

                  (iii)    Solicit for employment for his own or another's
                           benefit (as employee, partner, independent contractor
                           or otherwise) any person who has been employed by the
                           Company or any affiliate within the two year period
                           in question.

8.       RESTRICTIONS ON THE EXECUTIVE.

         (A) As between the Company or any of its affiliates or subsidiaries, as
the case may be, and the Executive, all products, methods, processes,
discoveries, materials, ideas, creations, inventions and properties pertaining
to the business of the Company or any affiliate or subsidiary, whether or not
developed or invented by the Executive 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 Executive 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 Executive 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, technical systems and
procedures, inventions, manuals, confidential reports and customer business. The
Executive 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 Executive), he will not, for any
purposes, 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.

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9.       TERM OF EMPLOYMENT.

         The term of this Agreement shall initially continue until June 30,
1995. It shall continue indefinitely thereafter, unless and until terminated by
either party upon delivery, thereafter, of one year's prior written notice of
termination to the other party.

         Notwithstanding the foregoing, the Company shall be entitled by notice
in writing to the Executive to terminate forthwith his employment with the
Company under this Agreement if he shall be guilty of any misconduct or commit
any material breach of his obligations to the Company hereunder; and the
Executive shall be entitled by notice in writing to the Company to terminate his
employment within 30 days if the Company shall be in material breach of its
obligations hereunder.

10.       VACATION.

         The Executive shall be entitled to four weeks of vacation in each year.

11.      RETURN OF DOCUMENTS.

         The Executive shall promptly, upon the termination of his employment
with the Company hereunder, deliver to the Company all office copies of reports,
memoranda, accounts, 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 Executive 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.

         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 the respective heirs, executors, and successors in interest. The
provisions of Sections 7, 8, 11 and 14 hereunder shall survive the termination
of this Agreement to the extent necessary to accomplish the purposes of such
provisions.

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l4.      GOVERNING LAW.

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


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

                                                BIONEBRASKA, INC.

                                                By /s/ Fred W. Wagner
                                                   ---------------------------
                                                         President
/s/ Thomas R. Coolidge
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THOMAS R. COOLIDGE
(the Executive)