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                                                                    Exhibit 10.1

                              EMPLOYMENT AGREEMENT


                              ANTEX BIOLOGICS INC.



    THIS EMPLOYMENT AGREEMENT (the "Agreement"), made as of July 31, 2000
is entered into by Antex Biologics Inc., a Delaware corporation with its
principal place of business at 300 Professional Drive, Gaithersburg, Maryland
20879 (the "Company"), and STEPHEN N. KEITH, M.D., residing at 12615 Fawn Run
Court, Ellicott City, Maryland 21042 (the "Employee").

                                   WITNESSETH:

         WHEREAS, the Company desires to employ the Employee, and the Employee
desires to be employed by the Company;

         NOW THEREFORE, in consideration of the mutual covenants and promises
contained herein, and other good and valuable consideration, the receipt and
sufficiency of which are hereby acknowledged by the parties hereto, the parties
agree as follows:

         1.       Term of Employment. The Company hereby agrees to employ the
Employee, and the Employee hereby accepts employment with the Company, upon the
terms set forth in this Agreement, for the period commencing on July 31, 2000
(the "Commencement Date") and ending on July 31, 2003 (such period, as it may be
extended, the "Employment Period"), unless sooner terminated in accordance with
the provisions of Section 4 hereof. Upon the third anniversary of the
Commencement Date and upon every third anniversary of the Commencement Date
thereafter, the term of the Employment Period shall be extended automatically
for three (3) additional years unless, at least six months prior to such
anniversary, the Company shall have delivered to the Employee or, at least six
(6) months prior to such anniversary, the Employee shall have delivered to the
Company, written notice that the term of the Employee's employment hereunder
will not be extended.

         2.       Title; Capacity. The Employee shall serve as President and
Chief Operting Officer or in such other position as the Company or its Board of
Directors (the "Board") may determine from time to time. The Employee shall be
based at the Company's headquarters in Gaithersburg, Maryland, or such place or
places in the continental United States as the Board shall determine. The
Employee shall be subject to the supervision of, and shall have such authority
as is delegated to him by, the Board or such officer of the Company as may be
designated by the Board.

         The Employee hereby accepts such employment and agrees to undertake the
duties and responsibilities inherent in such position and such other duties and
responsibilities as the Board or its designee shall from time to time reasonably
assign to him. The Employee agrees

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to devote his entire business time, attention and energies to the business and
interests of the Company during the Employment Period. He shall not engage in
any other business activity, except as may be approved by the Company. The
Employee agrees to abide by the rules, regulations, instructions, personnel
practices and policies of the Company and any changes therein which may be
adopted from time to time by the Company. The Employee acknowledges receipt of
copies of all such rules and policies committed to writing as of the date of
this Agreement.

         3.       Compensation and Benefits.

                  3.1      Salary. The Company shall pay the Employee, in
semi-monthly installments on the 15th and month-end or on the last working day
of such month, an annual base salary (the "Annual Base Salary") of Two Hundred
Thousand Dollars ($200,000) for the period commencing on the Commencement Date.
Thereafter, upon each anniversary of the Commencement Date (including the first
anniversary thereof), following an annual review by the Board, the Board may
adjust the Employee's Annual Base Salary as it determines in its sole
discretion; provided, however, that the Board of Directors shall not reduce the
Annual Base Salary.

                  3.2      Fringe Benefits. The Employee shall be entitled to
participate in all bonus, stock option, benefit and insurance programs that the
Company establishes and makes available to its employees, if any, to the extent
that Employee's position, tenure, salary, age, health and other qualifications
make him eligible to participate.

The Employee shall be entitled to twenty (20) days paid vacation per year, to be
taken at such times as may be approved by the Board or its designee.

                  3.3      Reimbursement of Expenses. The Company shall
reimburse the Employee for all reasonable travel, entertainment and other
expenses incurred or paid by the Employee in connection with, or related to, the
performance of his duties, responsibilities or services under this Agreement,
upon presentation by the Employee of documentation, expense statements, vouchers
and/or such other supporting information as the Company may request; provided,
however, that the amount available for such travel, entertainment and other
expenses may be fixed in advance by the Board.

                  3.4      Bonus. The Employer shall, subject to approval of the
Board, pay to the Employee an appropriate bonus (the "Bonus") with respect to
each completed year of employment. The Bonus shall be paid to Employee in one
lump sum on or prior to January 31 of each year for the one-year period of
employment, or portion thereof, ending on the preceding December 31.

         4.       Employment Termination. The employment of the Employee by the
Company pursuant to this Agreement shall terminate upon the occurrence of any of
the following:



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                  4.1      Expiration of the Employment Period in accordance
with Section 1 hereof and if the term is not extended in accordance with Section
1 hereof, then the provisions of Section 4.4 hereof shall apply;

                  4.2      At the election of the Company, for cause,
immediately upon written notice by the Company to the Employee. For the purposes
of this Section 4.2, cause for termination shall be deemed to exist upon (a) a
good faith finding by the Company of failure of the Employee to perform his
assigned duties for the Company, dishonesty, gross negligence or misconduct, or
(b) the conviction of the Employee of, or the entry of a pleading of guilty or
nolo contendere by the Employee to, any crime involving moral turpitude or any
felony;

                  4.3      Upon the death or ninety (90) days after the
disability of the Employee. As used in this Agreement, the term "disability"
shall mean the inability of the Employee, due to a physical or mental
disability, for a period of ninety (90) days, whether or not consecutive, during
any three hundred sixty (360)-day period to perform the services contemplated
under this Agreement. A determination of disability shall be made by a physician
satisfactory to both the Employee and the Company, provided that if the Employee
and the Company do not agree on a physician, the Employee and the Company shall
each select a physician and these two together shall select a third physician,
whose determination as to disability shall be binding on all parties;

                  4.4      At the election of the Company, upon not less than
six (6) months' prior written notice of termination to the Employee. At the
option of the Company and in lieu of such notice, the Company may pay to
Employee in a lump sum payment an amount equal to (i) six (6) months' salary
computed on the basis of the then current Annual Base Salary plus (ii) any bonus
to which Employee is entitled. If the Company elects to pay such amount in lieu
of notice it shall, at the expense of the Company, continue Employee's
participation in all benefits programs including but not limited to medical,
disability and life insurance programs provided by the Company to the Employee
under Section 3.2 hereof on the date on which such amount is paid (the "Payment
Date") until a date six (6) months after the Payment Date. In the event
Employee's termination is related to a "change of control" and occurs within one
(1) year of such change of control the notice or salary in lieu of notice and
participation in the benefits program will be for twelve (12) months. In the
event that Employee commences employment or self-employment during the period
the Company is making payments then the salary payment maybe reduced by the
amount the Employee receives through employment or self-employment and the
benefits will terminate on the date Employee becomes eligible to participate in
the benefits program pursuant to employment or self-employment. The exercise of
stock options and any modifications to the exercise period will be in accordance
with the Company's Amended and Restated Stock Option Plan.

                  4.5      At the election of the Employee, upon not less than
six (6) months prior written notice of termination to the Company.

         5.       Effect of Termination.

                  5.1      Termination for Cause or at Election of Either Party.
In the event the Employee's employment is terminated for cause pursuant to
Section 4.2 hereof, or at the



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election of the Employee pursuant to Section 4.5 hereof, the Company shall pay
to the Employee the compensation and benefits otherwise payable to him under
Section 3 hereof through the last day of his actual employment by the Company.

                  5.2      Termination for Death or Disability. If the
Employee's employment is terminated by death or because of disability pursuant
to Section 4.3 hereof, the Company shall pay to the estate of the Employee or to
the Employee, as the case may be, the compensation which would otherwise be
payable to the Employee up to the end of the month in which the termination of
his employment because of death or disability occurs.

                  5.3      Survival. The provisions of Sections 6 and 7 hereof
shall survive the termination of this Agreement.

         6.       Non-Competition.

                  (a)      During the Employment Period and for a period of two
(2) years after the termination or expiration thereof, the Employee will not
directly or indirectly:

                           (i)      as an individual proprietor, partner,
    stockholder, officer,employee, director, joint venturer, investor, lender,
    or in any other capacity whatsoever (other than as the holder of not more
    than one percent (1%) of the total outstanding sock of a publicly held
    company), engage in the business of developing, producing, marketing or
    selling products of the kind or type developed or being developed, produced,
    marketed or sold by the Company while the Employee was employed by the
    Company; or

                           (ii)     recruit, solicit, or induce, or attempt to
    induce, any employee or employees of the Company to terminate their
    employment with, or otherwise cease their relationship with, the Company; or

                           (iii)    solicit, divert or take away, or attempt to
    divert or to take away, the business or patronage of any of the clients,
    customers or accounts, or prospective clients, customers or accounts, of the
    Company which were contacted, solicited or served by the Employee while
    employed by the Company.

                  (b)      If any restriction set forth in this Section 6 is
found by any court of competent jurisdiction to be unenforceable because it
extends for too long a period of time or over too great a range of activities or
in too broad a geographic area, it shall be interpreted to extend only over the
maximum period of time, range of activities or geographic area as to which it
may be enforceable.

                  (c)      The restrictions contained in this Section 6 are
necessary for the protection of the business and goodwill of the Company and are
considered by the Employee to be reasonable for such purpose. The Employee
agrees that any breach of this Section 6 will cause the Company substantial and
irrevocable damage and therefore, in the event of any such



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breach, in addition to such other remedies which may be available, the Company
shall have the right to seek specific performance and injunctive relief.

    7.   Proprietary Information and Development.

                  7.1      Proprietary Information.

                  (a)      Employee agrees that all information and know-how,
whether or not in writing, or a private, secret or confidential nature
concerning the Company's business or financial affairs (collectively,
"Proprietary Information") is and shall be the exclusive property of the
Company. By way of illustration, but not limitation, Proprietary Information may
include inventions, products, processes, methods, techniques, formulas,
compositions, compounds, projects, developments, plans, research data, clinical
data, financial data, personnel data, computer programs, and customer and
supplier lists. Employee will not disclose any Proprietary Information to others
outside the Company or use the same for any unauthorized purposes without
written approval by an officer of the Company, either during or after his
employment, unless and until such Proprietary Information has become public
knowledge without fault by the Employee.

                  (b)      Employee agrees that all files, letters, memoranda,
reports, records, data, sketches, drawings, laboratory notebooks, program
listings, or other written, photographic, or other tangible material containing
Proprietary Information, whether created by the Employee or others, which shall
come into his custody or possession, shall be and are the exclusive property of
the Company to be used by the Employee only in the performance of his duties for
the Company.

                  (c)      Employee agrees that his obligation not to disclose
or use information, know-how and records of the types set forth in paragraphs
(a) and (b) above, also extends to such types of information, know-how, records
and tangible property of customers of the Company or suppliers to the Company or
other third parties who may have disclosed or entrusted the same to the Company
or to the Employee in the course of the Company's business.

                  7.2      Developments.

                  (a)      Employee will make full and prompt disclosure to the
Company of all inventions, improvements, discoveries, methods, developments,
software, and works of authorship, whether patentable or not, which are created,
made, conceived or reduced to practice by the Employee or under his direction or
jointly with others during his employment by the Company, whether or not during
normal working hours or on the premises of the Company (all of which are
collectively referred to in this Agreement as "Developments").

                  (b)      Employee agrees to assign and does hereby assign to
the Company (or any person or entity designated by the Company) all his right,
title and interest in and to all Developments and all related patents, patent
applications, copyrights and copyright applications. However, this Section 7.2
(b) shall not apply to Developments which do not related to the present or
planned business or research and development of the Company and which are made



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and conceived by the Employee not during normal working hours, not on the
Company's premises and not using the Company's tools, devices, equipment or
Proprietary Information.

                  (c)      Employee agrees to cooperate fully with the Company,
both during and after his employment with the Company, with respect to the
procurement, maintenance and enforcement of copyrights and patents (both in the
United States and foreign countries) relating to Developments. Employee shall
sign all papers, including, without limitation, copyright applications, patent
applications, declarations, oaths, formal assignments, assignment of priority
rights, and powers of attorney, which the Company may deem necessary or
desirable in order to protect its rights and interests in any Development.

                  7.3      Other Agreements. Employee hereby represents that he
is not bound by the terms of any agreement with any previous employer or other
party to refrain from using or disclosing any trade secret or confidential or
proprietary information in the course of his employment with the Company or to
refrain from competing, directly or indirectly, with the business of such
previous employer or any other party. Employee further represents that his
performance of all terms of this Agreement and as an employee of the Company
does not and will not breach any agreement to keep in confidence proprietary
information, knowledge or data acquired by him in confidence or in trust prior
to his employment with the Company.

         8.       Notices. All notices required or permitted under this
Agreement shall be in writing and shall be deemed effective upon personal
delivery or upon deposit in the United States Post Office, by registered or
certified mail, postage prepaid, addressed to the other party at the address
shown above, or at such other address or addresses as either party shall
designate to the other in accordance with this Section 9.

         9.       Pronouns. Whenever the context may require, any pronouns used
in this Agreement shall include the corresponding masculine, feminine or neuter
forms, and the singular forms of nouns and pronouns shall include the plural,
and vice versa.

         10.      Entire Agreement. This Agreement constitutes the entire
agreement between the parties and supersedes all prior agreements and
understandings, whether written or oral, relating to the subject matter of this
Agreement.

         11.      Amendment. This Agreement may be amended or modified only by a
written instrument executed by both the Company and the Employee.

         12.      Governing Law. This Agreement shall be construed, interpreted
and enforced in accordance with the laws of the State of Maryland.

         13.      Successors and Assigns. This Agreement shall be binding upon
and inure to the benefit of both parties and their respective successors and
assigns, including any corporation with which or into which the Company may be
merged to which may succeed to its assets or business, provided, however, that
the obligations of the Employee are personal and shall not be assigned by him.




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         14.      Miscellaneous.

                  14.1     No delay or omission by the Company in exercising any
right under this Agreement shall operate as a waiver of that or any other right.
A waiver or consent given by the Company on any one occasion shall be effective
only in that instance and shall not be construed as a bar or waiver of any right
on any other occasion.

                  14.2     The captions of the sections of this Agreement are
for convenience of reference only and in no way define, limit of affect the
scope or substance of any section of this Agreement.

                  14.3     In case any provision of this Agreement shall be
invalid, illegal or otherwise unenforceable, the validity, legality and
enforceability of the remaining provisions shall in no way be affected or
impaired thereby.

         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the day and year set forth above.

                                         ANTEX BIOLOGICS INC.


                                         by    /s/V.M. Esposito
                                             ------------------
                                             V. M. Esposito, Ph.D.
                                             Chairman of the Board of Directors


                                         Employee

                                               /s/Stephen N. Keith
                                             ---------------------
                                             Stephen N. Keith, MD, MSPH



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