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                                                                   EXHIBIT 10.50

                              EMPLOYMENT AGREEMENT

      THIS EMPLOYMENT AGREEMENT ("Agreement") is made and entered into as of
March 31, 2006 and is effective as of January 1, 2006 (the "Effective Date"), by
and between BOSTON LIFE SCIENCES, INC., a Delaware corporation (the "Company"),
and Kenneth L. Rice Jr. ("Executive").

AGREEMENT

1.    EMPLOYMENT

      The Company hereby employs Executive and Executive hereby accepts
employment upon the terms and conditions set forth below.

2.    TERM AND RENEWAL

      2.1 Term. The term of this Agreement shall commence on the Effective Date,
and shall continue for one (1) year from the Effective Date (the "Original
Employment Term"), on the terms and conditions set forth below, unless sooner
terminated as provided in Section 5.

      2.2 Extension. Following the expiration of the Original Employment Term
and provided that this Agreement has not been terminated pursuant to Section 5,
and every year thereafter, the Agreement shall be automatically renewed for an
additional 12 month period (the "Extension Period"), effective on each
anniversary date of the Effective Date, unless either party notifies the other
party in writing not less than 90 days prior to the expiration of the Original
Employment Term or any subsequent 12 month period.

3.    COMPENSATION

      3.1 Base Compensation. For the services to be rendered by Executive under
this Agreement, Executive shall be entitled to receive an initial annual base
compensation ("Base Compensation") of $300,000, payable in substantially equal
twice-monthly installments. Thereafter, the Base Compensation shall be reviewed
and adjusted annually as determined by the Compensation Committee (the
"Compensation Committee") of the Board of Directors (the "Board") of the
Company, or if there is no Compensation Committee, then by the Board provided,
however, in no event may the Base Compensation be adjusted below the initial
annual Base Compensation set forth in this Section 3.1.

      3.2 Bonus Compensation. The Compensation Committee shall review
Executive's performance at least annually during each year of the Original
Employment Term and during any periods of automatic extension of this Agreement
pursuant to Section 2.2 and cause the Company to award Executive a cash bonus
targeted at 25% of the Executive's Base Compensation which the Compensation
Committee shall reasonably determine as fairly compensating and rewarding
Executive for services rendered to the Company and/or as an incentive for
continued service to the Company. The amount of such cash bonus shall be
determined in the sole and absolute discretion of the Compensation Committee,
shall be

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dependent on, among other things, the achievement of certain performance levels
by the Company, including, without limitation, growth in funds from operations,
and Executive's performance and contribution to increasing the funds from
operations.

      3.3 Benefits.

            (a) Medical Insurance. The Company shall provide to Executive and
Executive's spouse and children, at its sole cost, such health, dental and
optical insurance as the Company may from time to time make available to its
other executive employees.

            (b) Life and Disability Insurance. The Company shall provide
Executive such disability and life insurance as the Company in its sole
discretion may from time to time make available to its other executive
employees.

            (c) Pension Plans, Etc. Executive shall be entitled to participate
in all pension, 401(k) and other employee plans and benefits established by the
Company on at least the same terms as the Company's other executive employees.

      3.4 Vacation. Executive shall be entitled to four (4) vacation weeks (20
business days) in each calendar year, subject to and on a basis consistent with
Company policy. In addition, Executive shall be entitled to all Company holidays
and other paid time off in accordance with Company policy.

4.    POSITION AND DUTIES

      4.1 Position. Executive shall serve as Executive Vice President, Finance
and Administration and Chief Financial Officer. The Company agrees that the
duties that may be assigned Executive shall be the usual and customary duties of
the Executive Vice President, Finance and Administration and Chief Financial
Officer. Executive shall have such executive power and authority as shall
reasonably be required to enable Executive to discharge the duties of such
offices. At the Company's request, Executive may, at Executive's discretion,
serve the Company and its respective subsidiaries in other offices and
capacities in addition to the foregoing, but shall not be required to do so. In
the event the Company and Executive mutually agree that Executive shall
terminate Executive's service in any one or more of the aforementioned
capacities, or Executive's service in one or more of the aforementioned
capacities is terminated, Executive's compensation, as specified in this
Agreement, shall not be diminished or reduced in any manner.

      4.2 Devotion of Time and Effort. Executive shall use Executive's good
faith best efforts and judgment in performing Executive's duties as required
hereunder and to act in the best interests of the Company. Executive shall
devote substantially all of his business time and attention to the performance
of services of the Company in his capacity as an officer thereof and as may
reasonably be requested by the Board.

      4.3 Other Activities. Executive may engage in other activities for
Executive's own account while employed hereunder, including, without limitation,
charitable, community and other business activities, provided that such other
activities do not materially interfere with the performance of Executive's
duties hereunder.

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      4.4 Business Expenses. The Company shall promptly, but in no event later
than ten business days after submission of a claim of expenditure, reimburse
Executive for all reasonable business expenses including, without limitation,
business seminar fees, professional association dues, bar dues and reasonable
entertainment expenses incurred by Executive in connection with the business of
the Company, upon presentation to the Company of written receipts for such
expenses. Such reimbursement shall also include, but not be limited to,
reimbursement for all reasonable travel expenses, including all airfare, hotel
and rental car expenses incurred by Executive in traveling in connection with
the business of the Company.

      4.5 Company's Obligations. The Company shall provide Executive with any
and all necessary or appropriate current financial information and access to
current information and records regarding all material transactions involving
the Company, including but not limited to acquisition of assets, personnel
contracts, dispositions of assets, service agreements and registration
statements or other state or federal filings or disclosures, reasonably
necessary for Executive to carry out Executive's duties and responsibilities
hereunder. In addition, the Company agrees to provide Executive, as a condition
to Executive's services hereunder, such staff, equipment and office space as is
reasonably necessary for Executive to perform Executive's duties hereunder.

5.    TERMINATION

      5.1 By Company Without Cause. The Company may terminate this Agreement
without "cause" (as hereinafter defined) at any time following the Effective
Date, provided that the Company first deliver to Executive the Company's written
election to terminate this Agreement at least 90 days prior to the effective
date of termination.

      5.2 Severance Payment.

            (a) Amount. In the event the Company terminates Executive's services
hereunder without cause pursuant to Section 5.1 or by Executive pursuant to
Section 5.5, Executive shall continue to render services to the Company pursuant
to this Agreement until the date of termination and shall continue to receive
compensation, as provided hereunder, through the termination date. In addition
to other compensation payable to Executive for services rendered through the
termination date, the Company shall pay Executive no later than the date of such
termination, as a single severance payment, an amount equal to (i) Executive's
highest monthly Base Compensation paid hereunder during the preceding 12 month
period, multiplied by 9, plus (ii) 9/12 the average annual bonus (excluding any
bonus payment deemed by the Compensation Committee in its sole discretion to be
a "Special Bonus") received by the Executive during the preceding twenty-four
month period (the "Severance Amount").

            (b) Benefits. In the event Executive's employment hereunder is
terminated by the Company without cause pursuant to Section 5.1 , by the Company
with cause on account of Executive's Disability (as defined in Section 5.3(d)
hereof), or by Executive pursuant to Section 5.5, then in addition to paying
Executive the Severance Amount, the Company shall continue to pay for and
provide to Executive and Executive's spouse and children, as applicable, all of
the benefits described in Section 3.3 for a period of 9 months commencing on the
date of such termination (the "Severance Benefits").

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            (c) Acceleration of Vesting. In the event Executive's employment
hereunder is terminated by the Company without cause pursuant to Section 5.1 or
by Executive pursuant to Section 5.5, then in addition to paying Executive the
Severance Amount and the Severance Benefits, the vesting of (i) the unvested
portion of any stock option to purchase Company common stock granted to
Executive ("Stock Options") and (ii) any shares of Company common stock granted
to Executive which is subject to forfeiture ("Restricted Stock"), shall be
accelerated and shall become fully vested and immediately exercisable and all
Stock Options shall be exercisable through the earlier of the expiration date of
the option provided for in the option grant agreement (without regard to
termination of employment)(the "Final Exercise Date") or 24 months following the
Termination date and, with respect to Restricted Stock, shall cease to be
subject to forfeiture. Notwithstanding the preceding sentence, in the case of
any Stock Options that are outstanding on the date of this Agreement, the
extension of the exercise period provided for in the preceding sentence shall
not extend the period during which such Stock Options may be exercised beyond
the date that is the later of the fifteenth day of the third month following the
date, or December 31 of the calendar year in which, the Stock Option would
otherwise have expired if the exercise period had not been extended based on the
terms of such options at the original grant date.

      5.3 By the Company For Cause. The Company may terminate Executive for
cause at any time, upon written notice to Executive. For purposes of this
Agreement, "cause" shall mean:

            (a) Executive's conviction for commission of a felony;

            (b) Executive's willful commission of any act of theft, embezzlement
or misappropriation against the Company;

            (c) Executive's willful and continued failure to substantially
perform Executive's duties hereunder (other than such failure resulting from
Executive's incapacity due to physical or mental illness), which failure is not
remedied within a reasonable time after written demand for substantial
performance is delivered by the Company which specifically identifies the manner
in which the Company believes that Executive has not substantially performed
Executive's duties; or

            (d) Executive's death or Disability (as hereinafter defined).

      In the event Executive is terminated for cause pursuant to this Section
5.3, Executive shall have the right to receive Executive's compensation as
otherwise provided under this Agreement through the effective date of
termination. Executive shall have no further right to receive compensation or
other consideration from the Company or have any other remedy whatsoever against
the Company as a result of this Agreement or the termination of Executive
pursuant to this Section 5.3, except as set forth below with respect to a
termination due to Executive's Disability.

      In the event Executive is terminated by reason of Executive's Disability,
the Company shall immediately pay Executive or his or her estate a single
severance payment equal to the Severance Amount. Said payment shall be in
addition to any life insurance or disability insurance payments to which
Executive or his or her estate is otherwise entitled and any other

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compensation earned by Executive hereunder. For purposes of this Agreement, the
term "Disability" shall mean death or (a) that the Executive is unable to engage
in any substantial gainful activity by reason of any medically determinable
physical or mental impairment that can be expect to result in death or can be
expected to last for a continuous period of not less than 12 months, (b) that
the Executive is, by reason of any medically determinable physical or mental
impairment that can be expected to result in death or can be expected to last
for a continuous period of not less than 12 months, receiving income replacement
benefits for a period of not less than 3 months under an accident and health
plan covering employees of the Company, or (c) that the Executive has been
determined to be totally disabled by the Social Security Administration.

      5.4 Executive's Voluntary Termination. Executive may, at any time,
terminate this Agreement upon written notice delivered to the Company at least
90 days prior to the effective date of termination. In the event of such
voluntary termination of this Agreement by Executive: (i) Executive shall have
the right to receive Executive's compensation as provided hereunder through the
effective date of termination; and (ii) the Company on the one hand, and
Executive, on the other hand, shall not have any further right or remedy against
one another except as provided in Sections 6, 7 and 8 hereof which shall remain
in full force and effect.

      5.5 Change of Control. Executive may terminate this Agreement, upon at
least 10 days' prior written notice to the Company at any time within one year
after a "change in control" (as hereinafter defined) of the Company. In the
event Executive terminates this Agreement within one year after a change in
control pursuant to this Section 5.5, (i) Executive shall continue to render
services pursuant hereto and shall continue to receive compensation, as provided
hereunder, through the termination date, (ii) the Company shall pay Executive no
later than the date of such termination, as a single severance payment, an
amount equal to the Severance Amount and (iii) following such termination, the
Company shall provide the Severance Benefits as required by Section 5.2(b). For
purposes of this Agreement, a "change in control" shall mean the occurrence of
any of the following events:

            (a) an acquisition of any voting securities of the Company (the
"Voting Securities") by any "person" (as the term "person" is used for purposes
of Section 13(d) or Section 14(d) of the Securities Exchange Act of 1934, as
amended (the "1934 Act")) immediately after which such person has "beneficial
ownership" (within the meaning of Rule 13d-3 promulgated under the 1934 Act) of
45% or more of the combined voting power of the Company's then outstanding
Voting Securities; or

            (b) approval by the stockholders of the Company of:

                  (i) a merger, consolidation, share exchange or reorganization
of the Company, unless the stockholders of the Company, immediately before such
merger, consolidation, share exchange or reorganization, own, directly or
indirectly immediately following such merger, consolidation, share exchange or
reorganization, at least 51% of the combined voting power of the outstanding
voting securities of the corporation that is the successor in such merger,
consolidation, share exchange or reorganization (the "Surviving Company") in
substantially the same proportion as their ownership of the Voting Securities
immediately before such merger, consolidation, share exchange or reorganization;
or

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                  (ii) a complete liquidation or dissolution of the Company; or

                  (iii) an agreement for the sale or other disposition of all or
substantially all of the assets of the Company.

      5.6 Required Delay. Notwithstanding any provision of this Agreement to the
contrary, if, at the time the Executive's employment is terminated, the
Executive is a "specified employee" within the meaning of Section
409A(a)(2)(B)(ii) of the Internal Revenue Code of 1986 (the "Code") and the
regulations thereunder, then any payments under this Agreement to the Executive
that constitute "nonqualified deferred compensation" within the meaning of
Section 409A of the Code shall be delayed by a period of six months and (i) all
payments that would have been made to the Executive during such six month period
shall be made in a lump sum in the seventh month following the date of
termination and (ii) all remaining payments shall commence in the seventh month
following the date of termination.

6.    NON-SOLICITATION

      For a period of one year following the date Executive's employment
hereunder is terminated, Executive shall not solicit or induce any of the
Company's employees, agents or independent contractors to end their relationship
with the Company, or recruit, hire or otherwise induce any such person to
perform services for Executive, or any other person, firm or company. The
restrictions set forth in this Section 7 shall not apply if Executive's
employment is terminated pursuant to Section 5.1 or 5.5.

7.    NON-COMPETITION AFTER TERMINATION

      Executive agrees to be bound by the terms of the Confidential Information
and Non-Competition agreement attached hereto as Exhibit A and incorporated
herein by reference.

8.    INDEMNIFICATION

      To the fullest extent permitted under applicable law, the Company shall
indemnify, defend and hold Executive harmless from and against any and all
causes of action, claims, demands, liabilities, damages, costs and expenses of
any nature whatsoever (collectively, "Damages") directly or indirectly arising
out of or relating to Executive discharging Executive's duties hereunder on
behalf of the Company, so long as Executive acted in good faith within the
course and scope of Executive's duties with respect to the matter giving rise to
the claim or Damages for which Executive seeks indemnification.

9.    GENERAL PROVISIONS

      9.1 Assignment; Binding Effect. Neither the Company nor Executive may
assign, delegate or otherwise transfer this Agreement or any of their respective
rights or obligations hereunder without the prior written consent of the other
party. Any attempted prohibited assignment or delegation shall be void. This
Agreement shall be binding upon and inure to the benefit of any permitted
successors or assigns of the parties and the heirs, executors, administrators
and/or personal representatives of Executive.

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      9.2 Notices. All notices, requests, demands and other communications that
are required or may be given under this Agreement shall be in writing and shall
be deemed to have been duly given where received if personally delivered; when
transmitted if transmitted by telecopy, electronic or digital transmission
method with electronic confirmation of receipt; the day after it is sent, if
sent for next-day delivery to a domestic address by recognized overnight
delivery service (e.g., FEDEX); and upon receipt, if sent by certified or
registered mail, return receipt requested. In each case notice shall be sent to:

      If to the Company:     Boston Life Sciences, Inc.
                             85 Main Street
                             Hopkinton, MA 01748

                             Attention: Chief Executive Officer
                             Facsimile: 508-497-9664

      If to Executive:       Kenneth L. Rice Jr.

Any party may change its address for the purpose of this Section 9.2 by giving
the other party written notice of its new address in the manner set forth above.

      9.3 Entire Agreement. This Agreement constitutes the entire agreement of
the parties, and supersedes all prior agreements, understandings and
negotiations, whether written or oral, between the Company and Executive with
respect to the employment of Executive by the Company.

      9.4 Amendments; Waivers. This Agreement may be amended or modified, and
any of the terms and covenants may be waived, only by a written instrument
executed by the parties hereto, or, in the case of a waiver, by the party
waiving compliance. Any waiver by any party in any one or more instances of any
term or covenant contained in this Agreement shall neither be deemed to be nor
construed as a further or continuing waiver of any such term or covenant of this
Agreement.

      9.5 Provision; Severable. In case any one or more provisions of this
Agreement shall be invalid, illegal or unenforceable in any respect, the
validity, legality and enforceability of the remaining provisions contained
herein shall not, in any way, be affected or impaired thereby. If any provision
hereof is determined by any court of competent jurisdiction to be invalid or
unenforceable by reason of such provision extending the covenants and agreements
contained herein for too great a period of time or over too great a geographical
area, or being too extensive in any other respect, such provision shall be
interpreted to extend only over the maximum period of time and geographical
area, and to the maximum extent in all other respects, as to which it is valid
and enforceable, all as determined by such court in such action.

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      9.6 Attorneys' Fees. If any legal action, arbitration or other proceeding,
is brought for the enforcement of this Agreement, or because of an alleged
dispute, breach or default in connection with any of the provisions of this
Agreement, the prevailing party shall be entitled to recover reasonable
attorneys' fees and other costs incurred in that action or proceeding, including
any appeal of such action or proceeding, in addition to any other relief to
which that party may be entitled.

      9.7 Section 409A. All payments and benefits provided under this Agreement
are intended to either comply with or be exempt from Section 409A of the Code
and this Agreement shall be administered and construed accordingly.

      9.8 Governing Law. This Agreement shall be construed, performed and
enforced in accordance with, and governed by the laws of the State of Delaware
without giving effect to the principles of conflict of laws thereof.

      9.9 Counterparts. This Agreement may be executed in one or more
counterparts, each of which shall be deemed an original, but all of which shall
constitute the same instrument.

                            [Signature Page Follows]

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

THE COMPANY

BOSTON LIFE SCIENCES, INC.
a Delaware corporation

By: /s/ Peter G. Savas
    -----------------------
    Peter G. Savas.
    Chief Executive Officer

EXECUTIVE

/s/ Kenneth L. Rice, Jr.
---------------------------
Kenneth L. Rice, Jr.

<PAGE>

                                    EXHIBIT A

              CONFIDENTIAL INFORMATION AND NONCOMPETITION AGREEMENT

To: Boston Life Sciences, Inc.                           Date:

      The undersigned, in consideration of and as a condition of my employment
or continued employment by you and/or by companies that you own, control, or are
affiliated with or their successors in business (collectively, the "Company"),
hereby agrees as follows:

      1. Confidentiality. I agree to keep confidential, except as the Company
may otherwise consent in writing, and except for the Company's benefit, not to
disclose or make any use of at any time either during or subsequent to my
employment, any Inventions (as hereinafter defined), trade secrets, confidential
information, knowledge, data or other information of the Company relating to
products, franchises, processes, know-how, techniques, methods, designs,
formulas, test data, customer lists, business plans, marketing plans and
strategies, pricing strategies, or other subject matter pertaining to any
business of the Company or any of its affiliates, which I may produce, obtain,
or otherwise acquire during the course of my employment, except as herein
provided. I further agree not to deliver, reproduce or in any way allow any such
trade secrets, confidential information, knowledge, data or other information,
or any documentation relating thereto, to be delivered to or used by any third
parties without specific direction or consent of the Chairman of the Board or
the Chief Executive Officer of the Company. The provisions of this Section 1
shall not apply to such knowledge, data or other information that is generally
known to the public.

      2. Conflicting Employment; Return of Confidential Material. I agree that
during my employment with the Company I will not engage in any other employment,
occupation, consulting or other activity relating to the business in which the
Company is now or may hereafter become engaged, or which would otherwise
conflict with my obligations to the Company. In the event my employment with the
Company terminates for any reason whatsoever, I agree to promptly surrender and
deliver to the Company all trade secrets, confidential information, processes
and records, including, but not limited to, designs, formulae, test data,
customer lists, business plans and strategies, Inventions or other written
memoranda, materials, equipment, drawings, documents and data that I may obtain
or produce during the course of my employment, and I will not take with me any
description containing or pertaining to any confidential information, knowledge
or data of the Company that I may produce or obtain during the course of my
employment.

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      3. Assignment of Inventions.

            3.1 I hereby acknowledge and agree that the Company is the owner of
all Inventions. In order to protect the Company's rights to such Inventions, by
executing this Agreement I hereby irrevocably assign to the Company all my
right, title and interest in and to all Inventions to the Company.

            3.2 For purposes of this Agreement, "Inventions" shall mean all
discoveries, processes, designs, technologies, methods, techniques, devices, or
improvements in any of the foregoing or other ideas, whether or not patentable
or copyrightable and whether or not reduced to practice, made or conceived by me
(whether solely or jointly with others) during the period of my employment with
the Company that relate to the actual or demonstrably anticipated business,
work, or research and development of the Company, or result from or are
suggested by any task assigned to me or any work performed by me for or on
behalf of the Company.

            3.3 Any discovery, process, design, method, technique, technology,
device, or improvement in any of the foregoing or other ideas, whether or not
patentable or copyrightable and whether or not reduced to practice, made or
conceived by me (whether solely or jointly with others) that I develop entirely
on my own time not using any of the Company's equipment, supplies, facilities,
or trade secret information ("Personal Invention") is excluded from this
Agreement provided such Personal Invention (a) does not relate to the actual or
demonstrably anticipated business, research and development of the Company, and
(b) does not result, directly or indirectly, from any work performed by me for
the Company.

      4. Disclosure of Inventions. I agree that in connection with any
Invention, I will promptly disclose such Invention to the Board of Directors of
the Company in order to permit the Company to enforce its property rights to
such Invention in accordance with this Agreement. My disclosure shall be
received in confidence by the Company. If the Company in good faith decides not
to use an Invention, it will advise me of same and the rights to such Invention
will revert to me within a reasonable period of time.

      5. Patents and Copyrights; Execution of Documents.

            5.1 Upon request, I agree to assist the Company or its nominee (at
its expense) during and at any time subsequent to my employment in every
reasonable way to obtain for its own benefit patents and copyrights for
Inventions in any and all countries. Such patents and copyrights shall be and
remain the sole and exclusive property of the Company or its nominee. I agree to
perform such lawful acts as the Company deems to be necessary to allow it to
exercise all right, title and interest in and to such patents and copyrights.

            5.2 In connection with this Agreement, I agree to execute,
acknowledge and deliver to the Company or its nominee upon request and at its
expense all documents, including assignments of title, patent or copyright
applications, assignments of such applications, assignments of patents or
copyrights upon issuance, as the Company may determine necessary or desirable to
protect the Company's or its nominee's interest in Inventions, and/or to use in

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obtaining patents or copyrights in any and all countries and to vest title
thereto in the Company or its nominee to any of the foregoing.

      6. Maintenance of Records. I agree to keep and maintain adequate and
current written records of all Inventions made by me (in the form of notes,
sketches, drawings, flowcharts, printouts, diskettes and other records as may be
specified by the Company), which records shall be available to and remain the
sole property of the Company at all times.

      7. Prior Inventions. It is understood that all Personal Inventions, if
any, whether patented or unpatented, which I made prior to my employment by the
Company, are excluded from this Agreement. To preclude any possible uncertainty,
I have set forth on Schedule A attached hereto a complete list of all of my
prior Personal Inventions, including numbers of all patents and patent
applications and a brief description of all unpatented Personal Inventions that
are not the property of a previous employer. I represent and covenant that the
list is complete and that, if no items are on the list, I have no such prior
Personal Inventions. I agree to notify the Company in writing before I make any
disclosure or perform any work on behalf of the Company that appears to threaten
or conflict with proprietary rights I claim in any Personal Invention. In the
event of my failure to give such notice, I agree that I will make no claim
against the Company with respect to any such Personal Invention.

      8. Other Obligations. I acknowledge that the Company from time to time may
have agreements with other persons, companies, entities, Governments or agencies
thereof, that impose obligations or restrictions on the Company regarding
Inventions made during the course of work thereunder or regarding the
confidential nature of such work. I agree to be bound by all such obligations
and restrictions and to take all actions necessary to discharge the Company's
obligations.

      9. Trade Secrets of Others. I represent that my performance of all the
terms of this Agreement and as an employee of the Company does not and will not
breach any agreement to keep confidential proprietary information, knowledge, or
data acquired by me in confidence or in trust prior to my employment with the
Company, and I will not disclose to the Company, or induce the Company to use,
any confidential or proprietary information or material belonging to any
previous employer or others. I agree not to enter into any agreement either
written or oral in conflict herewith.

      10. Post-Employment Activities.

            10.1 For a period of one (1) year after the termination, for any
reason, of my employment with the Company, absent the Company's prior written
approval, I will not directly or indirectly engage in activities similar or
reasonably related to those in which I shall have engaged for the Company during
the two years immediately preceding termination, nor render services similar or
reasonably related to those which I shall have rendered during such time to, any
person or entity whether existing or hereafter established that directly
competes with (or proposes or plans to directly compete with) the Company, or in
other areas where the Company carries on a substantial amount of business
("Direct Competitor"). In addition, I shall not entice,

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induce or encourage any of the Company's other employees to engage in any
activity that, were it done by me, would violate any provision of this
Agreement.

            10.2 No provision of this Agreement shall be construed to preclude
me from performing the same services that the Company retains me to perform for
any person or entity that is not a Direct Competitor of the Company upon the
termination of my employment (or any post-employment consultation) so long as I
do not thereby violate any term of this Agreement.

      11. Remedies. My obligations under this Agreement shall survive the
termination of my employment with the Company. I acknowledge that a remedy at
law for any breach or threatened breach by me of the provisions of this
Agreement would be inadequate and I therefore agree that the Company shall be
entitled to injunctive relief in case of any such breach or threatened breach.

      12. Modification. I agree that any subsequent change or changes in my
employment duties, salary or compensation or, if applicable, in any Employment
Agreement between the Company and me, shall not affect the validity or scope of
this Agreement.

      13. Successors and Assigns. This Agreement shall be binding upon my heirs,
executors, administrators or other legal representatives and is for the benefit
of the Company, its successors and assigns.

      14. Interpretation. IT IS THE INTENT OF THE PARTIES THAT in case any one
or more of the provisions contained in this Agreement shall, for any reason, be
held to be invalid, illegal or unenforceable in any respect, such invalidity,
illegality or unenforceability shall not affect the other provisions of this
Agreement, and this Agreement shall be construed as if such invalid, illegal, or
unenforceable provision had never been contained herein. MOREOVER, IT IS THE
INTENT OF THE PARTIES THAT if any provision of this Agreement is or becomes or
is deemed invalid, illegal or unenforceable or in case any one or more of the
provisions contained in this Agreement shall for any reason be held to be
excessively broad as to duration, geographical scope, activity or subject, such
provision shall be construed by amending, limiting and/or reducing it to conform
to applicable laws so as to be valid and enforceable or, if it cannot be so
amended without materially altering the intention of the parties, it shall be
stricken and the remainder of this Agreement shall remain in full force and
effect.

      15. Waivers. No waiver of any right under this Agreement shall be deemed
effective unless contained in a writing signed by the party charged with such
waiver, and no waiver of any right arising from any breach or failure to perform
shall be deemed to be a waiver of any future such right or of any other right
arising under this Agreement. If either party should waive any breach of any
provision of this Agreement, he or it shall not thereby be deemed to have waived
any preceding or succeeding breach of the same or any other provision of this
Agreement.

      16. Complete Agreement, Amendments. The foregoing is the entire agreement
of the parties with respect to the subject matter hereof, superseding any
previous oral or written communications, representations, understandings, or
agreements with the Company or any officer or representative thereof. Any
amendment to this Agreement or waiver by the Company

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<PAGE>

of any right hereunder shall be effective only if evidenced by a written
instrument executed by the parties hereto, upon authorization of the Company's
Board of Directors.

      17. Headings. The headings of the Sections contained in this Agreement are
inserted for convenience and reference only and in no way define, limit, extend
or describe the scope of this Agreement, or the intent of any provision hereof,
and shall not be deemed to constitute a part hereof nor to affect the meaning of
this Agreement in any way.

      18. Governing Law. This Agreement shall be governed by and construed in
accordance with the internal laws of the Commonwealth of Massachusetts,
excluding its conflict of law principles.

      19. Notices. All notices, requests, demands and communications which are
or may be required to be given hereunder shall be deemed effectively given if
and when sent by registered or certified mail, return receipt requested, postage
prepaid, to the following addresses:

          If to the Company:

          If to Employee:

      21. Conflicts. In the event of any conflict between the provisions of this
agreement and the provisions of the Employment Agreement, the provisions of the
Employment Agreement will govern.

                                                    Very truly yours,

Agreed:
Boston Life Sciences, Inc.

By: _____________________________

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