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                                                                    Exhibit 10.1



                              EMPLOYMENT AGREEMENT


         AGREEMENT made as of March 14, 2001, between BIO-TECHNOLOGY GENERAL
CORP., a Delaware corporation with an office at 70 Wood Avenue South, Iselin,
New Jersey 08830 (the "Company") and Bernard R. Tyrrell, having a residence at
31 Fischer Farm Road, Belle Mead, New Jersey 08502 (the "Executive").


                              W I T N E S S E T H:

         WHEREAS, the Company desires that Executive be employed to serve in a
senior executive capacity with the Company, and Executive desires to be so
employed by the Company, upon the terms and conditions herein set forth.

         NOW, THEREFORE, in consideration of the premises and of the mutual
promises, representations and covenants herein contained, the parties hereto
agree as follows:

1.       EMPLOYMENT.

         The Company hereby employs Executive and Executive hereby accepts such
employment, subject to the terms and conditions herein set forth. Executive
shall hold the office of Senior Vice President, Marketing and Sales, reporting
to the President of the Company. During any periods that the position of
President is vacant, the Executive shall report, during the period of such
vacancy, to the Chief Executive Officer.

2.       TERM.

         The initial term of employment under this Agreement shall begin on the
date hereof (the "Employment Date") and shall continue for a period of two (2)
years from that date, subject to prior termination in accordance with the terms
hereof. Thereafter, this Agreement shall automatically be renewed for successive
two (2) year terms unless either party shall give the other ninety (90) days
prior written notice of its intent not to renew this Agreement.

3.       COMPENSATION.

         (a) As compensation for the employment services to be rendered by
Executive hereunder, including all services as an officer or director of the
Company and any of its subsidiaries, the Company agrees to pay, or cause to be
paid, to Executive, and Executive agrees to accept, payable in equal
installments in accordance with Company practice, an initial annual salary of
$230,000. Executive's annual salary hereunder for the remaining years of
employment shall be determined by the Board of Directors in its sole discretion;
provided, however, that Executive's annual salary shall not be reduced during
the term of


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this Agreement below the highest annual salary paid to Executive at any time
during such term.

         (b) Executive shall be entitled to bonuses from time to time in such
amounts as may be determined by the Board of Directors in its sole discretion.

4.       EXPENSES.

         The Company shall pay or reimburse Executive, upon presentment of
suitable vouchers, for all reasonable business and travel expenses that may be
incurred or paid by Executive in connection with his employment hereunder.
Executive shall comply with such restrictions and shall keep such records as the
Company may deem necessary to meet the requirements of the Internal Revenue Code
of 1986, as amended from time to time, and regulations promulgated thereunder.

5.       OTHER BENEFITS.

         Executive shall be entitled to a vacation allowance of not less than
four (4) weeks per annum and to participate in and receive any other benefits
customarily provided by the Company to its senior management personnel
(including any profit sharing, pension, short and long-term disability
insurance, hospital, major medical insurance, dental insurance and group life
insurance plans in accordance with the terms of such plans) and including stock
option and/or stock purchase plans, all as determined from time to time by the
Board of Directors of the Company. Unused annual vacation may not be carried
over to other years except that with the consent of the Chief Executive Officer
the Executive may carry over unused vacation in those instances in which
Executive has been unable to utilize fully his annual vacation entitlement due
to exigencies of Company business matters and needs.

6.       DUTIES.

         (a) Executive shall perform such duties and functions as the
President or Chief Executive Officer of the Company shall from time to time
determine in accordance with what it is normal and customary for an
individual holding Executive's position to perform, and Executive shall
comply in the performance of such duties and functions with the policies of
the Board of Directors.

         (b) Executive agrees to devote his entire working time, attention
and energies to the performance of the business of the Company and of any of
its subsidiaries by which he may be employed; and Executive shall not without
the approval of the Board of Directors, directly or indirectly, alone or as a
member of any partnership or other business organization, or as an officer,
director or employee of any other corporation, partnership or other business
organization, be actively engaged in or concerned with any other duties or
pursuits of a business nature which interfere with the performance of his
duties hereunder, or which, even if non-interfering, may be, in the
reasonable

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determination of the Board of Directors of the Company in its sole discretion,
inimical, or contrary, to the best interests of the Company.

          (c) All fees, compensation or commissions received by Executive
during the term of this Agreement for personal services (including, but not
limited to, commissions and compensation received as a fiduciary or a
director, and fees for lecturing and teaching) rendered at the request of the
Company shall be paid to the Company when received by Executive, except those
fees that the Board of Directors determines may be kept by Executive.

          (d) Nothing in this Section 6 or elsewhere in this Agreement shall
be construed to prevent Executive from investing or trading in
non-conflicting investments as he sees fit for his own account, including
real estate, stocks, bonds, securities, commodities or other forms of
investments.

          (e) The principal location at which the Executive shall perform his
duties hereunder shall be at the Company's offices in Iselin, New Jersey or
at such other location as may be designated from time to time by the Board of
Directors of the Company, provided that if the principal location of
Executive's duties is transferred from Iselin, New Jersey, the new principal
location of Executive's duties shall not be transferred beyond a 50-mile
radius of Iselin, New Jersey without Executive's consent. Notwithstanding the
foregoing, Executive shall perform such services at such other locations as
may be required from the proper performance of his duties hereunder, and
Executive recognizes that such duties may involve significant travel.

7.       TERMINATION OF EMPLOYMENT; EFFECT OF TERMINATION.

         (a) Executive's employment hereunder may be terminated at any time upon
written notice from the Company to Executive:

                  (i)      upon the determination by the Board of Directors,
                           after Executive has received notice that his
                           performance is not satisfactory for any reason which
                           would not constitute justifiable cause (as defined in
                           7(d)) and which notice specifies with reasonable
                           particularity how such performance is not
                           satisfactory, that Executive has failed to remedy
                           such performance to the reasonable satisfaction of
                           the Board of Directors within thirty (30) days of
                           such notice; or

                  (ii)     upon the determination by the Board of Directors that
                           there is justifiable cause (as defined in 7(d)) for
                           such termination and upon ten (10) days' prior
                           written notice of same to Executive.


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         (b)      Executive's employment shall terminate upon:

                  (i)      the death of Executive; or

                  (ii)     the "disability" of Executive (as defined in 7(c))
                           pursuant to 7(f) hereof.

         (c) For the purposes of this Agreement, the term "disability" shall
mean the inability of Executive, due to illness, accident or any other physical
or mental incapacity, substantially to perform his duties for a period of three
(3) consecutive months or for a total of six (6) months (whether or not
consecutive) in any twelve (12) month period during the term of this Agreement,
as reasonably determined by the Board of Directors of the Company in its sole
discretion after examination of Executive by an independent physician reasonably
acceptable to Executive.

         (d) For the purposes hereof, the term "justifiable cause" shall mean
and be limited to:

                  (i)      Executive's conviction (which, through lapse of time
                           or otherwise, is not subject to appeal) of any crime
                           or offense involving the Company's or its
                           subsidiaries' money or other property or which
                           constitutes a felony in the jurisdiction involved;

                  (ii)     Executive's performance of any act or his failure to
                           act, for which it is determined by independent
                           counsel retained by the Board of Directors (which
                           counsel shall not be an individual or firm which at
                           any time within the prior three (3) years has
                           represented the Company, any executive employed by
                           the Company, the Board of Directors or any individual
                           Director), after due inquiry in which Executive is
                           given the opportunity to be heard and represented by
                           counsel, that if Executive were prosecuted, a crime
                           or offense involving money or property of the Company
                           or its subsidiaries, or which would constitute a
                           felony in the jurisdiction involved, would have
                           occurred and Executive would, in all reasonable
                           probability, be convicted; provided, however, that if
                           such independent counsel does not make such
                           determination, then the Company shall pay Executive's
                           reasonable counsel fees and expenses incurred in
                           defending Executive during such inquiry;

                  (iii)    any disclosure which has not been authorized or
                           subsequently ratified by the Company or which is not
                           required to be made pursuant to any judicial
                           proceeding or by statute or regulation, by Executive
                           to any person, firm or corporation other than the
                           Company, its subsidiaries and its and their
                           directors, officers and



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                           employees, of any confidential information or trade
                           secret of the Company or any of its subsidiaries;

                  (iv)     any attempt by Executive to secure any improper
                           personal profit in connection with the business of
                           the Company or any of its subsidiaries; or

                  (v)      Executive's repeated and willful failure to comply
                           with his duties under 6(a) or 6(b) (other than
                           failure to comply with instructions or policies which
                           are illegal or improper) where such conduct shall not
                           have ceased or been cured within thirty (30) days
                           following receipt by Executive of written warning
                           from the Board of Directors.

Upon termination of Executive's employment for justifiable cause, this Agreement
shall terminate immediately and Executive shall not be entitled to any amounts
or benefits hereunder other than such portion of Executive's annual salary as
has been accrued through the date of his termination of employment and
reimbursement of expenses pursuant to Section 4 hereof.

          (e) If Executive shall die during the term of his employment
hereunder, this Agreement shall terminate immediately. In such event, the
estate of Executive shall thereupon be entitled to receive such portion of
Executive's annual salary as has been accrued through the date of his death
and such bonus, if any, as the Board of Directors in its sole discretion may
determine to award taking into account Executive's contributions to the
Company prior to his death. If Executive's death shall occur while he is on
Company business, the estate of Executive shall be entitled to receive, in
addition to the other amounts set forth in this subsection (e), an amount
equal to one-half of his then annual salary.

          (f) Upon Executive's "disability", the Company shall have the right
to terminate Executive's employment. Notwithstanding any inability to perform
his duties, Executive shall be entitled to receive his compensation
(including bonus, if any) as provided herein until he begins to receive
long-term disability insurance benefits under the policy provided by the
Company pursuant to Section 5 hereof (the period during which Executive
continues to receive his compensation hereunder being the "Transition
Period"). During the Transition Period, the Company shall (i) allow Executive
to participate in the Company's 401k plan to the extent permitted by such
plan and (ii) at Company's expense and to the same extent that Executive had
participated, prior to termination of his employment, in the Company's health
insurance, dental insurance, life insurance and disability insurance
programs, continue Executive's participation in such programs. Any
termination pursuant to this subsection (f) shall be effective on the date
thirty (30) days after which Executive shall have received written notice of
the Company's election to terminate.


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         (g) Notwithstanding any provision to the contrary contained herein, in
the event that Executive's employment is terminated by the Company at any time
for any reason other than justifiable cause, disability or death, or in the
event the Company shall fail to renew this Agreement:

                  (i)      each month during the Severance Period, the Company
                           shall pay to Executive, in full satisfaction and in
                           lieu of any and all other payments due and owing to
                           Executive under the terms of this Agreement (other
                           than any payments constituting reimbursement of
                           expenses pursuant to Section 4 hereof), an amount
                           equal to one-twelfth of the sum of his then annual
                           salary plus the amount of the last bonus awarded to
                           Executive (less all amounts, if any, required to be
                           withheld), payable bi-weekly;

                           (A)      The "Severance Period" shall commence on the
                                    date of termination and shall comprise one
                                    month for each month that Executive was
                                    employed by Company, provided however, that
                                    in no event shall such period be less than
                                    six (6) months nor more than twelve (12)
                                    months.

                  (ii)     Executive shall have a right to exercise any options
                           which are exercisable as of the date of termination
                           at any time during a period of six (6) months
                           following the effective date of termination;

                  (iii)    the Company shall continue to allow Executive to
                           participate in the Company's 401k plan to the extent
                           permitted by such plan for twelve (12) months
                           following the effective date of termination; and

                  (iv)     the Company shall continue to allow Executive to
                           participate, at the Company's expense and to the same
                           extent that Executive had participated prior to
                           termination of his employment, in the Company's
                           health insurance, dental insurance, life insurance
                           and disability insurance programs, to the extent
                           permitted under such programs, until the earlier of
                           the expiration of the Severance Period or until such
                           time as Executive becomes eligible to participate in
                           another employer's group health, dental and
                           disability insurance plans; provided, however, that
                           Executive shall notify the Company of his acceptance
                           of a position with a new employer, together with the
                           specific date on which Executive shall become
                           eligible for coverage in such new employer's health,
                           dental, life and disability insurance programs, such
                           notice to be given within fifteen (15) days following
                           commencement of such employment.


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         (h) Executive may terminate his employment at any time upon thirty (30)
days' prior written notice to the Company. Upon Executive's termination of his
employment hereunder, this Agreement (other than Sections 4, 7, 10, 11, 12 and
13, which shall survive) shall terminate immediately. In such event, Executive
shall be entitled to receive such portion of Executive's annual salary as has
been accrued to date. Executive shall be entitled to reimbursement of expenses
pursuant to Section 4 hereof and to participate in the Company's benefit plans
to the extent participation by former employees is required by law or permitted
by such plans, with the expense of such participation to be specified in such
plans for former employees.

8.       REPRESENTATIONS AND AGREEMENTS OF EXECUTIVE.

         (a) Executive represents and warrants that he is free to enter into
this Agreement and to perform the duties required hereunder, and that there are
no employment contracts or understandings, restrictive covenants or other
restrictions, whether written or oral, preventing the performance of his duties
hereunder or requiring him to perform employment, consulting, business related
or similar duties for any other person.

         (b) Executive agrees to submit to a medical examination and to
cooperate and supply such other information and documents as may be required by
any insurance company in connection with the Company's obtaining life insurance
on the life of Executive, and any other type of insurance or fringe benefit as
the Company shall determine from time to time to obtain.

9.       REPRESENTATIONS OF COMPANY.

         The Company represents and warrants that the Board of Directors has
consented to the Company entering into this Agreement with Executive on the
terms set forth herein and that all written consents, resolutions and approvals
required to give full force and effect to this Agreement and to the Company's
obligations hereunder have been obtained.

10.      NON-INTERFERENCE.

         Executive agrees that for a period of one year following the
termination of Executive's employment hereunder, Executive shall not, directly
or indirectly, request or cause collaborative partners, universities,
governmental agencies, contracting parties, suppliers or customers with whom the
Company or any of its subsidiaries has a business relationship to cancel or
terminate any such business relationship with the Company or any of its
subsidiaries or solicit, interfere with or entice from the Company any employee
(or former employee) of the Company.


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11.      INVENTIONS AND DISCOVERIES.

          (a) Insofar as is related to the principal business activities and
products of the Company and any of its subsidiaries or joint ventures,
Executive shall promptly and fully disclose to the Company, and with all
necessary detail for a complete understanding of the same, all developments,
know-how, discoveries, inventions, improvements, concepts, ideas, writings,
formulae, processes and methods of a financial or other nature (whether
copyrightable, patentable or otherwise) made, received, conceived, acquired
or written during working hours, or otherwise, by Executive (whether or not
at the request or upon the suggestion of the Company) during the period of
his employment with, or rendering of advisory or consulting services to, the
Company or any of its subsidiaries, solely or jointly with others
(collectively the "Subject Matter").

          (b) Executive hereby assigns and transfers, and agrees to assign
and transfer, to the Company, all his rights, title and interest in and to
the Subject Matter, and Executive further agrees to deliver to the Company
any and all drawings, notes, specifications and data relating to the Subject
Matter, and to execute, acknowledge and deliver all such further papers,
including applications for copyrights or patents, as may be necessary to
obtain copyrights and patents for any thereof in any and all countries and to
vest title thereto to the Company. Executive shall assist the Company in
obtaining such copyrights or patents during the term of this Agreement, and
any time thereafter on reasonable notice and at mutually convenient times,
and Executive agrees to testify in any prosecution or litigation involving
any of the Subject Matter; provided, however, that Executive shall be
compensated in a timely manner at the rate of $250.00 per hour (with a
minimum of $1500 per day), plus out-of-pocket expenses incurred in rendering
such assistance or giving or preparing to give such testimony if it is
required of his employment hereunder.

12.      NON-DISCLOSURE OF CONFIDENTIAL INFORMATION.

          (a) Executive shall not, during the term of this Agreement, or at
any time following termination of this Agreement, directly or indirectly,
disclose or make accessible (other than as is required in the regular course
of his duties, including, without limitation, disclosures to the Company's
advisors and consultants), or as may be required by law or regulation or
pursuant to a judicial proceeding (in which case Executive shall give the
Company prior written notice of such required disclosure) or with the prior
written consent of the Board of Directors of the Company), to any person,
firm or corporation, any confidential information acquired by him during the
course of, or as an incident to, his employment or the rendering of his
advisory or consulting services hereunder, relating to the Company or any of
its subsidiaries, or any corporation, partnership or other entity owned or
controlled, directly or indirectly, by any of the foregoing, or in which any
of the foregoing has a beneficial interest, including, but not limited to,
the business affairs of each of the foregoing. Such confidential information
shall include, but shall not be limited to, proprietary technology, trade
secrets, patented processes, research and development data, know-how, market
studies and forecasts,

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competitive analyses, pricing policies, employee lists, personnel policies, the
substance of agreements with customers and others, marketing or dealership
arrangements, servicing and training programs and arrangements, customer lists
and any other documents embodying such confidential information. This
confidentiality obligation shall not apply to any confidential information which
thereafter becomes publicly available other than pursuant to a breach of this
Section 12(a) by Executive.

          (b) All information and documents relating to the Company and its
affiliates as hereinabove described shall be the exclusive property of the
Company, and Executive shall use commercially reasonable best efforts to
prevent any publication or disclosure thereof. Upon termination of
Executive's employment with the Company, all such documents, records,
reports, writings and other similar documents containing confidential
information, including copies thereof, then in Executive's possession or
control shall be returned and left with the Company.

13.      SPECIFIC PERFORMANCE.

         Executive agrees that if he breaches, or threatens to commit a breach
of, any of the provisions of Sections 10, 11 or 12 (the "Restrictive
Covenants"), the Company shall have, in addition to, and not in lieu of, any
other rights and remedies available to the Company under law and in equity, the
right to have the Restrictive Covenants specifically enforced by any court of
competent jurisdiction, it being agreed that any breach or threatened breach of
the Restrictive Covenants would cause irreparable injury to the Company and that
money damages would not provide an adequate remedy to the Company.
Notwithstanding the foregoing, nothing herein shall constitute a waiver by
Executive of his right to contest whether a breach or threatened breach of any
Restrictive Covenant has occurred.

14.      AMENDMENT OR ALTERATION.

         No amendment or alteration of the terms of this Agreement shall be
valid unless made in writing and signed by both of the parties hereto.

15.      GOVERNING LAW.

         This Agreement shall be governed by the laws of the State of New Jersey
applicable to agreements made and to be performed entirely therein.

16.      SEVERABILITY.

         The holding of any provision of this Agreement to be invalid or
unenforceable by a court of competent jurisdiction shall not affect any other
provision of this Agreement, which shall remain in full force and effect.


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17.      NOTICES.

         Any notices required or permitted to be given hereunder shall be
sufficient if in writing, and if delivered by hand, or sent by certified mail,
return receipt requested, to the addresses set forth above or such other address
as either party may from time to time designate in writing to the other, and
shall be deemed given as of the date of the delivery or date of receipt.

18.      WAIVER OR BREACH.

         It is agreed that a waiver by either party of a breach of any provision
of this Agreement shall not operate, or be construed, as a waiver of any
subsequent breach by that same party.

19.      ENTIRE AGREEMENT AND BINDING EFFECT.

         This Agreement contains the entire agreement of the parties with
respect to the subject matter hereof and shall be binding upon and inure to the
benefit of the parties hereto and their respective legal representatives, heirs,
distributors, successors and assigns. Notwithstanding the foregoing, any prior
agreements between Executive and the Company relating to the confidentiality of
information, trade secrets, patents, indemnification, and stock options shall
not be affected by this Agreement.

20.      SURVIVAL.

         The termination of Executive's employment hereunder or the expiration
of this Agreement shall not affect the enforceability of Sections 4, 7, 9, 10,
11, 12 and 13 hereof.

21.      FURTHER ASSURANCES.

         The parties agree to execute and deliver all such further documents,
agreements and instruments and take such other and further action as may be
necessary or appropriate to carry out the purposes and intent of this Agreement.

22.      HEADINGS.

         The Section headings appearing in this Agreement are for the purposes
of easy reference and shall not be considered a part of this Agreement or in any
way modify, demand or affect its provisions.


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         IN WITNESS WHEREOF, the parties hereto have executed this Agreement as
of the date and year first above written.


                                     BIO-TECHNOLOGY GENERAL CORP.



                                     By:    /s/ Sim Fass
                                         ---------------------------------------
                                              Sim Fass, Chairman and CEO

                                     Date:  March 14, 2001
                                          --------------------------------------




                                                  /s/ Bernard Tyrrell
                                     -------------------------------------------
                                                      Bernard Tyrrell

                                     Date:   March 2, 2001
                                           -------------------------------------