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                                                                    Exhibit 10.6

                TERMINATION OF AGREEMENT DATED SEPTEMBER 12,1990

     The Joint Development Agreement dated September 12,1990 between The
Population Council, Inc. ("The Council") and National Patent Development
Corporation ("NPDC"), for the joint development of hydrogel-type polymers as the
vehicle for the controlled parenteral release of LHRH as amended by the December
11, 1990 letter from Irene Frangos, Esq., to Karon Walker, Esq. (the "September
12, 1990 Agreement"), is hereby terminated in its entirety and superseded with
the following terms and conditions (the "Agreement").

1.   Representations and Warranties

     1.1 Representations and Warranties of The Council.  The Council hereby
represents that (a) it is a corporation duly organized, validly existing and in
good standing under the Not-for-Profit Corporation Law of the State of New York
and has full corporate power and authority to execute, deliver and perform this
Agreement; and (b) the execution, deliver and performance of this Agreement
have been authorized by all necessary corporate action on the part of The
Council.

     1.2 Representations and Warranties of NPDC.  NPDC hereby represents and
warrants that (a) it is a corporation duly organized, validly existing and in
good standing under the laws of the State of Delaware, and has full corporate
power and authority to execute, deliver and perform this Agreement; and (b) the
execution, delivery and performance of this Agreement have been authorized by
all necessary corporate action on the part of NPDC.

2.   Reciprocal Indemnities.

     2.1 Reciprocal Indemnities.  NPDC agrees to hold The Council and its
trustees, officers, agents and employees (each, a "Council Party") harmless
from, and indemnify it and each of them against, all Losses of any Council Party
incurred or payable by such Council Party that result from anything other than
(i) The Council's continuing obligations under paragraph 3 hereof or (ii) any
Council Party's gross negligence or willful misconduct. The Council agrees to
hold NPDC and its directors, officers, agents and employees (each, a "NPDC
Party") harmless from, and indemnify it and each of them against, all Losses of
any such NPDC Party that result from The Council's breach or alleged breach of
any representation or warranty made by The Council contained in this Agreement.
As used herein, "Losses" shall mean, with respect to any person or entity, any
and all liabilities, losses, damages, judgments, costs and expenses of any kind
(including reasonable attorneys' fees and disbursements) which may be imposed
on, incurred by, or asserted against such person or entity relating to or
arising out of, this Agreement or any transaction contemplated hereby or the
manufacture, sale or use of any Implant (as defined below) by NPDC or any
affiliate, officer, agent, employee, licensee, partner or contract party of
NPDC. This Paragraph 2.1 shall survive the termination or expiration of this
Agreement.


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     2.2 Notice: Control of Defense.  The Council or NPDC (in this capacity, the
"indemnitee") shall promptly notify the other party (the "indemnitor") of its
receipt of any threat, indication or other notice of any claim, suit or demand
which may give rise to any Loss within the purview of Paragraph 2.1. The
indemnitor shall promptly assume full control of the defense against any such
claim, suit or demand with the assistance of counsel reasonably satisfactory to
the indemnitee, and the indemnitee shall cooperate with indemnitor and such
counsel in the evaluation and defense thereof, provided that the indemnitor
shall reimburse the indemnitee for its out-of-pocket expenses (including without
limitation reasonable attorneys' fees and disbursements) in connection
therewith, which expenses shall not include the time value of the indemnitee's
employees or management. The indemnitee will not make any admission of liability
or responsibility, enter into any settlement, take any other action or incur any
expense (except reasonable attorneys' fees) with respect to any such claim, suit
or demand without the indemnitor's prior written consent, which shall not be
unreasonably withheld or delayed.

     2.3 Release.  Except with respect to Paragraphs 5.1 (a) and (b) and 6.1 of
the September 12, 1990 Agreement which shall survive termination hereof with
respect to any events which occurred prior to the effective date hereof, whether
such events are known or unknown on the date hereof, NPDC and The Council
release each other and their respective heirs, successors, assigns, corporate
parents, subsidiaries, affiliates, officers, directors, employees and agents
from any and all liability, responsibility, obligations, damages, expenses, or
claims of any sort at law and in equity, relating in any way to the September
12, 1990 Agreement.

3. The Council's Continuing Obligations.  The Council's continuing obligations
concerning the Implants (as that term is defined in Paragraph 4) shall be
limited to, at the Council's expense, (a) concluding the ongoing prostate cancer
clinical studies at all investigational sites according to IND protocols
submitted to the FDA (attached hereto as Exhibit A)* and (b) providing (or
giving NPDC access to) in a timely fashion, and in no event more than 30 days
after an NPDC request, such data, records, materials, and technical and
professional expertise, including but not limited to the "Council Proprietary
Rights," as that term is defined below, in the possession of the Council or
under its control, as shall reasonably be required by NPDC to further the
clinical trials and associated filings, correspondence and meetings in NPDC's
effort to secure the necessary regulatory approvals to commercially develop and
market the Implants. Such continuing obligations shall include those set forth
in Exhibit B, hereto, but shall not include: the funding or performance of any
clinical trials other than those set forth in clause 3 (a), above; or the
reimbursement of NPDC for any expenses incurred in connection with developing
the Implants.

     3.1 Council Proprietary Rights.  "Council Proprietary Rights" shall mean
all ideas, information and intellectual property, whether or not patentable,
including without limitation physical, chemical, clinical, toxicological,
performance and other information and data relating to the Implants or
applications thereof, including such ideas, information and intellectual
property owned, controlled, developed or reduced to practice by The Council
prior to the date hereof.

*    provided, however, that the Council shall not, in any case, be required to
     enroll any additional subjects at any such site after the date hereof.


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     3.2 Co-Exclusivity.  In the event that NPDC has not (a) submitted by
September 23, 2007, an NDA to the FDA, or (b) developed and introduced for
commercial sale in the United States by September 23,2010, in each case, with
respect to an LHRH Implant based in part or in whole upon Council Proprietary
Rights for application in the treatment of prostate cancer or symptoms thereof,
then NPDC hereby grants to The Council a co-exclusive license with NPDC to
develop and market such an LHRH Implant from and after the applicable such date;
provided, however, that if, on either date set forth in clause (a) or (b) above,
NPDC demonstrates to the reasonable satisfaction of The Council that it is
exercising, and will continue to exercise, due diligence in good faith either to
submit an NDA to the FDA or to develop and introduce such an LHRH Implant for
commercial sale in the United States, as applicable, then The Council hereby
agrees to extend for a reasonable time the applicable date on which such a
co-exclusive license will be granted pursuant to this Section 3.2.

          3.2.1 In the event that NPDC grants to The Council such a co-exclusive
license, each of The Council and NPDC shall pay to the other 50% of any
Royalties (as defined in Paragraph 5(d), below) that each receives from a
Licensee of the LHRH Implant.

          3.2.2 In the event that NPDC grants to The Council such a co-exclusive
license, The Council shall, or shall cause its Licensee to hold NPDC and its
directors, officers, agents and employees (each, a "NPDC Party") harmless from,
and indemnify it and each of them against, all Losses of any NPDC Party incurred
or payable by such NPDC Party that result from anything other than any NPDC
Party's gross negligence or willful misconduct.

          3.2.3 In the event that NPDC grants to The Council such a co-exclusive
license, The Council agrees to provide to NPDC the same certification and right
to audit as are provided to The Council in Paragraph 5(e) hereto.

     3.3 Failure to Comply.  Any failure to comply with the terms of paragraph 3
(a) and (b) shall be deemed a breach of a material term of this Agreement.

4. NPDC'S Authority.  NPDC shall have unilateral authority to enter into such
licensing and marketing agreements as it sees fit for the commercial development
of (a) subdermal implants, in dosage form, comprised of polymer(s) and any LHRH
analogue which in a hydrated state is capable of delivering LHRH at a
predetermined rate ("LHRH implants") and (b) any hydrogel implant drug delivery
system(s) comprised of copolymer(s) and any compounds, prodrugs or active agents
(excluding any LHRH analogue) to be used for any indication, and which, in a
hydrated state, is capable of delivering any compounds, prodrugs or active
agents (excluding any LHRH analogue) at a sustained rate ("Non-LHRH Implants")
(collectively, the LHRH and the Non-LHRH Implants shall hereinafter be referred
to as the "Implants"). the council shall not have the right to approve licensees
or marketing partners (collectively, "Licensees"), terms or conditions of
licenses or marketing arrangements, or any other matters that concern the
technical, regulatory or commercial development of the Implants. NPDC shall use
reasonable efforts to provide The Council notice of such licenses or marketing
arrangements within thirty (30) days of their execution.


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5. Allocation of Royalties.  NPDC shall pay to The Council within 30 days
following NPDC's receipt of Royalties, an amount equal to the following
percentages of Royalties (as that term is defined in Paragraph 5(d)).

     (a) One hundred (100%) percent of the first $35,000 of Royalties, as a fee
for the transfer of the IND sponsorship to NPDC from The Council.

     (b) In the case of any LHRH Implant, thirty (30%) percent.

     (c) In the case of any Non-LHRH Implant, five (5%) percent.

     (d) For the purposes of determining payments by NPDC to The Council,
Royalties shall mean revenues (or the fair market value of non-monetary
consideration) received by NPDC from Licensees, whether or not in the form of
royalties, prepaid royalties, advances on royalties, licensing fees, technology
transfer payments or other similar payments, in respect of licenses for the
Implants. Notwithstanding the foregoing, Royalties shall not include moneys
received by NPDC from Licensees and applied to product development costs,
including without limitation feasibility studies, pre-clinical studies,
animal studies, clinical trials, production scale-up, and regulatory compliance,
research fees and the manufacturing cost of Implants.

     (e) NPDC shall maintain, in accordance with generally accepted accounting
principles consistently applied, accurate records of all sales or other
disposition of any Implants upon which Royalties shall be payable pursuant to
this Paragraph 5. Within 120 days after the conclusion of each calendar year,
NPDC shall furnish to The Council a certification by its internal accountants
showing the quantity, sales prices, product development costs and Royalties due
with respect to sales of any Implants for the preceding year. Should The Council
wish to audit such records, it may engage, at its own expense, independent
public accountants reasonably acceptable to NPDC to conduct such an audit during
normal business hours and on reasonable notice to NPDC. The Council's right to
audit and bring any action with respect to a particular Royalty period shall be
limited to the two year period following the issuance of the certification. The
Council agrees to keep confidential all information relating to the business
affairs of NPDC, and to impose on its accountants a similar obligation.

     (f) Notwithstanding the foregoing, in no event shall amounts paid by NPDC
to The Council hereunder exceed the aggregate amount of $40,035,000.

6. Use of The Council's Name.  NPDC shall, in any promotional and other
materials or public information generated by NPDC relating to Implants, credit
The Council and its assistance in the development of the Implants in writing,
using language substantially in the following form: "This product has been
developed with the assistance of The Population Council, Inc." Any written
variation from or addition to the above description of The Council shall require
the prior written consent of The Council, which consent shall not be
unreasonably withheld or delayed, and shall be deemed given if no response is
received within 30 days.


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7. Termination

     7.1 Term.  The term of this Agreement shall be the shorter of twenty five
(25) years from the date hereof or until The Council has received $40,035,000 in
payments from NPDC, pursuant to Paragraph 5 hereof.

     7.2 Termination for Cause.  This Agreement may be terminated in accordance
with any of the following provisions:

          (a) Either party may terminate this Agreement at any time if the other
is in default of the performance of any material term or condition of this
Agreement, and such default continues unremedied for a period of thirty (30)
days after written notice thereof is given. In the event of failure to cure,
such termination shall become effective upon written notice at the end of
business on such thirtieth day; and

          (b) Either party may terminate this Agreement if a receiver or trustee
is appointed for all or substantially all of the other party's assets; if such
party becomes insolvent or unable to pay its debts at they mature, or makes an
assignment for the benefit of its creditors; or seeks protection from creditors
or if proceedings are commenced against it or on its behalf under any
bankruptcy, insolvency or debtor's relief law, and such proceedings have not
been vacated or set aside within sixty (60) days from the date of commencement
thereof; or if such party is liquidated or dissolved.

     7.3 No Waiver.  The election of either party to terminate this Agreement
pursuant to subparagraph 7.2 (a) hereof shall not serve to waive, limit, bar or
otherwise extinguish any right; such party may have to pursue and recover any
damages such party suffered or incurred due to the breach of any term or
condition of this Agreement.

8. Miscellaneous

     8.1 Independent Contractor.  The parties declare that each is an
independent contractor and not the agent or attorney-in-fact of the other, and
this Agreement shall not be deemed to create either a joint venture,
partnership, agency and/or employment relationship between the parties.

     8.2 Assignment.  This Agreement shall not be assigned by either party
without the prior written consent of the other party except to an affiliate of
either party or in connection with a merger, consolidation or sale of all or
substantially all of the assets of either party. This Agreement shall be binding
upon and shall inure to the benefit of the parties and their respective
successors and assignees.

     8.3 Notices.  All notices and other communications given hereunder shall be
in writing and shall be deemed to have been duly given when delivered by hand,
dispatched by registered mail, postage prepaid, addressed to the party at its
address set forth below, or if by facsimile, when transmitted to the facsimile
number of the party set forth below or to such other address or facsimile number
as may be furnished by such party by notice in the manner provided herein:


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The Council: One Dag Hammarskjold Plaza
             New York, New York 10017
             Attn: Margaret Catley-Carlson, President

             Facsimile: (212)755-6052

NPDC:        9 West 57th Street
             New York, New York 10019
             Attn: Jerome I. Feldman, President

             Facsimile: (212)230-9545

     8.4 Severability.  In the event that any one or more of the provisions
contained in this Agreement shall for any reason be held by a court of competent
jurisdiction to be unenforceable in any respect, such holding shall not affect
the other provisions of this Agreement, and the Agreement shall then be
construed as if such unenforceable provisions are not a part of it.

     8.5 Entire Agreement.  This Agreement, including the exhibits hereto,
represents the entire agreement between the parties relating to the matter
hereof, and shall supersede any other agreements, whether oral or written. There
are no understandings, representation or warranties of any kind except as
expressly set forth in this Agreement. No waiver, alteration or modification of
any of the provisions of this Agreement shall be binding on any party unless in
writing and signed by the party against whom enforcement of such waiver,
alteration or modification is sought.

     8.6 Headings.  The Section headings used in this Agreement are for purposes
of convenience or reference only. They shall not be used to explain, limit or
extend the meaning of any part of this Agreement.

     8.7 Governing Laws: Compliance.  THIS AGREEMENT SHALL BE CONSTRUED AND
INTERPRETED, AND THE LEGAL RELATIONS CREATED BY IT SHALL BE DETERMINED, IN
ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, APPLICABLE TO AGREEMENTS
MADE AND TO BE FULLY PERFORMED BY RESIDENTS THEREOF. EXCLUSIVE JURISDICTION,
OVER ALL DISPUTES HEREUNDER SHALL BE IN THE FEDERAL AND STATE COURTS IN THE
STATE OF NEW YORK LOCATED IN NEW YORK COUNTY. NPDC and The Council agree to
comply fully with all federal, state and local laws and regulations that are
applicable to them in carrying out their respective obligations hereunder.

     8.8 Survival.  Following the expiration or termination of this Agreement,
whether by its terms, operation of law or otherwise, indemnity obligations,
warranties and confidentiality or other undertakings of either party hereto
arising prior to the date of expiration or termination shall survive such
expiration or termination.


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     8.9 No Implied Agreements.  The parties intend to be bound only upon
execution of a written agreement and no negotiation, exchange of draft or
partial performance shall be deemed to imply an agreement.

     8.10 Remedies.  Except as expressly limited by this Agreement, all remedies
available to either party hereunder are cumulative, may be exercised
concurrently or separately, and are in addition to all other rights and remedies
available at law or in equity. The exercise of any one remedy shall not be
deemed to be an election of such remedy to the exclusion of other remedies.

     8.11 Counterparts.  This Agreement may be executed in counterparts and each
executed counterpart shall have the same force and effect as an original
instrument.

     8.12 Waiver, etc.  The waiver of a breach of or default under any provision
of this Agreement shall not be deemed a waiver of any subsequent breach or
default of any kind, or nature.

     8.13 No Third-Party Benefits.  Nothing in this Agreement shall be construed
to confer upon any person not a party hereto any right, remedy or claim
hereunder.

9. Confidentiality

     9.1 Confidentiality.  For the term of this Agreement, each of NPDC and The
Council shall hold, and shall cause each of its employees, consultants, agents
or licensees to hold, as confidential and as a trade secret essential to the
security of the other party, all nonpublic proprietary information received from
NPDC or The Council, as the case may be, hereunder, except as permitted in
writing by the other, provided that neither party shall be bound by the
provisions of this Section 9.1 with respect to any such information which (a)
has become, or becomes in the future, part of the public domain, other than as a
result of or in connection with a violation of any duty, liability or obligation
set forth herein; (b) is required to be disclosed by law; or (c) is necessary to
disclose to agents, employees, or Licensees. The Council and NPDC shall each
take such further action as shall be reasonably requested by the other to ensure
the safeguarding and confidentiality of any proprietary information required to
be held confidential by the terms hereof.


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     9.2 Publications.  Either party may, with the approval of the other party,
which approval shall not be unreasonably withheld or delayed, publish reports
concerning its activities hereunder, containing information not otherwise
subject to Section 9.1 hereof provided that (a) both parties shall have the
right to require the other to delay the publication of such reports for a
reasonable period for the purpose of obtaining patents and (b) each party shall
have the right to edit the information in the publication in a reasonable manner
in order to protect trade secrets.

     IN WITNESS WHEREOF, the parties have executed this Agreement as on the
dates set forth below.

NATIONAL PATENT DEVELOPMENT             THE POPULATION COUNCIL,
CORPORATION                             INC.


By: /s/ JEROME I. FELDMAN               By: /s/ SANDRA ARNOLD
   ----------------------------------       ------------------------------------
Name: JEROME I. FELDMAN                 Name: SANDRA ARNOLD
Title: PRESIDENT & CEO                  Title: VICE PRES., CORP. AFFAIRS
Date: 10/1/97                           Date: 9/26/97


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                                    EXHIBIT A

     PURSUANT TO SECTION 3(a), ABOVE, THE COUNCIL SHALL CONCLUDE THE ONGOING
PROSTATE CANCER CLINICAL STUDIES, ACCORDING TO THE IND PROTOCOLS SUBMITTED TO
THE FDA (THE FOLLOWING 15 PAGES), AT THE FOLLOWING INVESTIGATIONAL SITES:

     1.   THE ROCKEFELLER UNIVERSITY HOSPITAL, NEW YORK, NEW YORK;

     2.   THE GENERAL HOSPITAL, SALZBURG, AUSTRIA;

     3.   SHAARE ZEDEK MEDICAL CENTER, JERUSALEM, ISRAEL.


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