Document:

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                                                                   EXHIBIT 10.10

                     SOLE AND EXCLUSIVE LICENSE AGREEMENT
                                    Between
                            HIND HEALTH CARE, INC.
                                      And
                           ENDO PHARMACEUTICALS INC.

THIS AGREEMENT is effective as of the 20th day of November 1998, between Hind
Healthcare, Inc., a California corporation, having its principal office at Suite
101, 3707 Williams Road, San Jose, CA  95117-2017 ("HIND") and Endo
Pharmaceuticals Inc., a Delaware corporation, having its principal office at 223
Wilmington West Chester Pike, Chadds Ford, PA 19317 ("ENDO").

WITNESSETH THAT:

WHEREAS, HIND represents that it is the owner of certain patents, know-how and
trademarks for the topical treatment of post-herpetic neuralgia, other forms of
neuralgia and neuropathy and has the right to grant licenses to said patents,
know-how, and trademarks;

WHEREAS, ENDO is a pharmaceutical company engaged in research, development, and
marketing of various products, including pain management products;

WHEREAS, ENDO wishes to secure a license to said Hind patents, know-how, and
trademarks to develop, import, use, market, promote, and sell a pharmaceutical
product for the topical treatment of post-herpetic neuralgia, other forms of
neuralgia and neuropathy in the United States;

WHEREAS, HIND is willing to grant and Endo is willing to accept a license to
said Hind patents, know-how, and trademarks upon the terms and conditions
hereinafter set forth;

NOW, THEREFORE, in consideration of the covenants and obligations hereinafter
set forth and intending to be legally bound, the parties hereby agree as
follows:

I.  DEFINITIONS
    -----------

The following capitalized terms shall have the meanings set forth below for
purposes of this Agreement:

(a) "Affiliate" means any entity controlling, controlled by or under common
    control of either ENDO or HIND.  For purposes hereof, "control" shall mean
    ownership, directly or indirectly, of more than fifty percent (50%) of the
    securities having the right to vote for the election of directors, in the
    case of a corporation, and more than fifty percent (50%) of the beneficial
    interest in the capital, in the case of a business entity other than a
    corporation.

(b) "Approvable Letter" means a written communication from the FDA, in
    accordance with Section 21 CFR 314.110, which states that the NDA for the
    Product substantially meets all FDA requirements for approval to market,
    promote, and sell the Product in the Territory contingent upon the NDA
    applicant satisfactorily addressing any minor issues raised by the FDA.

The confidential portions of this exhibit have been filed separately with the
Securities and Exchange Commission pursuant to a confidential treatment request
in accordance with Rule 406 of the Securities Act of 1933.

            REDACTED PORTIONS OF THIS EXHIBIT ARE MARKED BY AN ***.

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HIND-ENDO
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(c) "Approval Letter" means a written communication from the FDA, in accordance
    with Section 21 CFR 314.105, which states that the NDA for the Product meets
    all FDA requirements for the Product and the Product may be marketed,
    promoted, and sold in the Territory.

(d) "Commercial Sale" means the sale for value of Product by ENDO to an
    unaffiliated third party.  Commercial Sale does not include transfer or sale
    of Product by ENDO to Affiliates or sublicensees nor any donation or
    transfer of Product free of charge by ENDO to unaffiliated third parties.

(e) "FDA" means the United States Food and Drug Administration.

(f) "FDA Communication" means any action, request, order, instruction,
    communication, complaint, notice, public announcement or inquiry by the FDA
    or any submission, filing, letter or other communication by HIND to the FDA,
    regarding the Product which is sent by or is received by HIND or which comes
    to Hind's or its agent's attention, including, but not limited to field
    actions, investigations or recalls of the Product in the Territory.

(g) "Intellectual Property Rights" means the Licensed Patents, Know-How, and
    Trademarks listed in Exhibit A which are necessary or useful for the
    development, manufacture, use, marketing, promotion, and sale of the Product
    and all improvements and enhancements thereto by HIND, TEIKOKU and/or any
    related party.

(h) "Know-how" means all information and data, regardless of form, which is
    necessary or useful for the development, use, marketing, promotion, and
    sale of the Product.

(i) "Licensed Patent" means the United States patents listed in Exhibit A owned
    in whole or in part or licensed or assigned to HIND and all reissues,
    extensions, substitutions, confirmations, registrations, revalidations,
    additions, continuations, continuations-in-part, and divisions thereof.

(j) "License Year" means a twelve (12) month period beginning on the date of the
    Product Launch and thereafter on the anniversary date thereof.

(k) "NDA" means the new drug application covering the Product on file with the
    FDA, as amended from time to time.

(l) "Net Sales" means the gross invoice price of Products sold by ENDO to any
    third party, excluding Affiliates and sublicensees, less (i) cash, trade,
    promotional, or quantity discounts and/or rebates, (ii) retroactive price
    reductions, (iii) sales, use, or other excise taxes, (iv) returns and
    allowances, (v) expired Products and (vi) transportation and/or shipping
    charges.

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HIND-ENDO
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(m) "Product" means any topical formulation of lidocaine in a bandage and/or
    transdermal (Patch) formulation, whether sold over-the counter or by
    prescription, for human use which falls within the claims of the Licensed
    Patents.

(n) "Product Launch" means the first Commercial Sale of the Product by ENDO for
    resale or use to an unaffiliated third party in the Territory.

(o) "Reasonable Commercial Efforts" means those efforts which would be made by a
    reasonably prudent business person acting in good faith, in the exercise of
    reasonable commercial judgment and in a manner consistent with those efforts
    a party devotes to a pharmaceutical product resulting from its own research
    efforts and having a similar market potential.

(p) "Related Agreement" means the Supply and Manufacturing Agreement entered
    into by Teikoku Seiyaku Co. Ltd., and Teikoku Pharma USA, Inc (collectively
    hereinafter referred to as "TEIKOKU"), the manufacturer of the transdermal
    delivery system for the Product and ENDO of even date herewith and attached
    hereto as Exhibits B made a part hereof.

q)  "Royalty Period" means the period commencing with the second (2nd)
    anniversary of the date of receipt by ENDO of HIND's receipt of notice of
    the Approval Letter by ENDO in the Territory until the shorter of (i) the
    life of the last issued Licensed Patent or (ii) thirteen (13) years from the
    effective date of this Agreement.

(r) "Submission Package" means all pre-clinical, laboratory, clinical,
    biocompatibility and other testing data, labeling, processing, material and
    packaging specifications, and supplements or amendments to the foregoing;
    and all other information in the possession of and used by HIND for
    submitting, obtaining, and maintaining approval of an NDA in accordance with
    the requirements of the Food Drug & Cosmetic Act, as amended, from time to
    time.

(s) "Supply and Manufacturing Agreement" means the Supply Agreement between
    TEIKOKU and ENDO of even date herewith and attached hereto as Exhibit B and
    made a part hereof.

(t) "Territory" means the United States, its territories, commonwealths, and
    possessions.

(u) "Trademark" shall mean the HIND trademarks "LIDODERM" or TAKON that may be
    used to market the Product in the Territory

II. LICENSE GRANT
    -------------

HIND hereby grants to ENDO and ENDO hereby accepts a sole and exclusive license,
including the right to sublicense, to all of the Intellectual Property Rights
including the rights to develop,  use, market, promote, and sell the Product in
the Territory.

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III. LICENSE FEES
     ------------

3.1 As consideration for entering into the binding Term Sheet between the
parties hereto, dated as of October 8, 1998, ENDO paid to HIND a fee of Fifty
Thousand Dollars ($50,000). Such fee shall be credited against the license fee
set forth in Paragraph 3.2 below and such license fee shall be reduced
accordingly.

3.2 ENDO shall pay HIND Two Million Dollars ($2,000,000), as part consideration
for the license granted by HIND to ENDO in Article 2 above, within fifteen (15)
business days of HIND's delivery to ENDO of the original Approvable Letter from
the FDA for the Product, provided, however, that the terms of such Approvable
Letter are reasonably acceptable to ENDO, at ENDO's discretion. In the event
that HIND is able to obtain an Approval Letter from the FDA with regard to the
Product, without having to first obtain an Approvable Letter as provided for
under this Paragraph, ENDO will still pay HIND the amount set forth in this
Paragraph in addition to the amount set forth in Paragraph 3.3 below, provided
that the Approval Letter contain terms that are reasonably acceptable to ENDO,
at ENDO's discretion.

3.3 ENDO shall pay HIND Six Million Dollars ($6,000,000), as part consideration
for the license granted by HIND to ENDO in Article 2 above, within fifteen (15)
business days of HIND's delivery to ENDO of the original Approval Letter from
the FDA for the Product.

3.4 ENDO shall pay HIND Two Million Dollars ($2,000,000), as part consideration
for the license granted by HIND to ENDO in Article 2 above, within fifteen (15)
business days of ENDO's Product Launch.

3.5  The payments set forth in Paragraphs 3.2, 3.3, and 3.4 above shall only be
paid upon the occurrence of the designated event.

IV.  ROYALTIES
     ---------

4.1  As part consideration  for the license granted by HIND to ENDO in Article 2
above, ENDO shall pay HIND royalty payments as follows:

     (a)  Commencing with the second (2nd) annual anniversary of the date of
          ENDO's receipt of the original Approval Letter for the Territory and
          for twelve (12) months thereafter, ENDO shall pay HIND an annual
          royalty of *** percent (***%) of Net Sales of the Product in the
          Territory.

     (b)  Commencing with the third (3rd) annual anniversary of the date of
          ENDO's receipt of the original Approval Letter for the Territory and
          until the shorter of the life of the last to expire Licensed Patent or
          thirteen (13) years from the effective date of this Agreement, ENDO
          shall pay HIND an annual royalty of *** (***%) percent of Net Sales of
          the Product in the Territory.

     (c)  Commencing with the second (2nd) annual anniversary of the date of
          ENDO's receipt of the original Approval Letter for the Territory and
          until the shorter of the life of the last to expire

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          Licensed Patent or thirteen (13) years from the effective date of this
          Agreement, ENDO shall pay to HIND annual royalties under this
          Agreement of at least *** for each twelve month (12) period
          thereafter. None of the minimum royalty payments are refundable once
          due and paid.

     (d)  Notwithstanding the provisions in Paragraphs 4.1 (a) through (c),
          ENDO's obligation to pay royalties, including minimum royalties, to
          HIND shall cease if the applicable claims in a Licensed Patent in the
          Territory are held invalid by an unappealed or unappealable decision
          of a court of competent jurisdiction in the Territory. In the event
          that ENDO's obligation to pay royalties terminates in accordance with
          this Paragraph, ENDO shall have the option to use the Trademarks upon
          payment of a *** percent (***%) royalty to HIND based on the royalty
          calculations set forth in this Agreement.

4.2 Royalty Reports.  ENDO will provide to HIND, within sixty (60) days after
    -----------------
the end of each calender quarter in a relevant twelve (12) month Royalty Period,
a written report setting forth the total Net Sales for the Product in the
Territory for that period and will accompany such report with an appropriate
payment of royalty or minimum royalty due for such period.  Any Royalty
payments, which are not paid on time, shall bear interest at the compounded rate
of *** percent (***%) per month.

4.3 Nothing contained herein shall obligate ENDO to pay HIND more than one
royalty on any unit of Product sold in the Territory, provided however, that
Endo shall be responsible for payment of all Royalties and delivery of all
Royalty Reports due hereunder, either from ENDO or its sublicenses.

V.  OBLIGATIONS OF THE PARTIES
    --------------------------

5.1 REGULATORY
    ----------

(a) FDA Communications.  Upon being contacted by the FDA for any regulatory
    -------------------
    purpose related to the Product or the NDA for the Product, HIND shall
    immediately notify ENDO.  ENDO shall be responsible for providing all
    responses directly to the FDA regarding inquiries related to the marketing,
    promotion, and/or sale of the Product, including any amendments or
    supplements to the NDA for the Product with regard to such issues.

(b) Ownership of the NDA.
    ----------------------

    (i)  The NDA for the Product shall be owned by TEIKOKU USA in accordance
         with a separately negotiated agreement between HIND and TEIKOKU USA.

    (ii) TEIKOKU shall be responsible for maintaining the good standing of the
         NDA for the Product in the Territory, in accordance with the
         applicable regulations and laws of the Territory. TEIKOKU obligations
         in this regard shall include, but shall not be limited to, the
         preparation and filing of any Submission Package for the Product to
         maintain ENDO's right to continue to market, promote, and sell the
         Product in the Territory and

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           the various statutory obligations of NDA owners as set forth on
           Exhibit C attached hereto and made a part hereof as amended from time
           to time by the FDA and other relevant authorities.

     (iii) Each party hereto shall provide the other parties copies of all new
           information, with regard to the Product. TEIKOKU and/or HIND will
           provide ENDO with copies of all information, with regard to the
           Product that they may file with regulatory authorities outside the
           Territory.

     (iv)  ENDO shall be solely responsible for the initiation and conduct of
           any clinical or other trial for additional indications for the
           Product, other than its current indication for post-herpetic
           neuralgia. Neither HIND nor TEIKOKU shall provide Product to any
           party for any use within the Territory, whether compassionate or
           otherwise, provided that ENDO will continue to fulfill the
           commitments and obligations made by HIND under its compassionate use
           program prior to the execution of the binding Term Sheet.

(c)  Adverse Drug Reactions
     ----------------------

     (i)   Adverse Reaction or Complaint: Each party hereto hereby agrees to
           -----------------------------
           notify the other party by facsimile with a follow up hard copy,
           within twenty-four hours (24) of receipt of any adverse reaction or
           complaint reported to it or its agent resulting from the use of the
           Product.

     (ii)  FDA Reporting.
           -------------

           (a) Adverse Reactions and Field Alerts: HIND/TEIKOKU will be
               ----------------------------------
               responsible for completion and submission to the FDA of any Form
               FDA 3500a with respect to an adverse reaction involving the
               Product or any complaint that would require a field alert, as and
               when appropriate, unless such request is made directly to ENDO
               and ENDO is under any statutory or regulatory obligation to make
               such or similar report or filing to the FDA. Each party will
               forward to the other a copy of each completed Form FDA3500a or
               similar report or filing with respect to the Product at least
               forty-eight (48) hours prior to filing such a report with the
               FDA.

           (b) Periodic Adverse Experiences Reports and Annual Reports:
               -------------------------------------------------------
               HIND/TEIKOKU will be responsible for completion of the periodic
               ADE (Adverse Drug Experiences) reports and annual reports
               required by the FDA with respect to the Product. HIND/TEIKOKU
               will forward to ENDO a copy of each such report dealing with the
               Product at least forty eight (48) hours before filing such with
               the FDA.

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5.2  MARKETING
     ---------

Reasonable Commercial Efforts.  ENDO shall use reasonable commercial efforts to
------------------------------
commercialize the Product and introduce the Product into the commercial market
in the Territory as soon as practical.

VI.  OPTION FOR ADDITIONAL TERRITORIES - CANADA and MEXICO
     -----------------------------------------------------

HIND hereby grants ENDO an option to extend this Agreement to cover a sole and
exclusive, license, on royalty terms that are substantially similar to those set
forth in this Agreement, with the right to sublicense, (subject to HIND's
approval which shall not be unreasonably withheld) to the Intellectual Property
Rights including the right to develop, use, market, promote, and sell Product in
Canada and Mexico.  ENDO must exercise this Option for each of these respective
territories within six (6) months of the regulatory registration of the Product
in each territory.

VII. OPTION FOR DEVELOPMENT PRODUCT
     ------------------------------

7.1  HIND hereby grants ENDO an option for a sole and exclusive license, with
the right to sublicense, to the Intellectual Property Rights including the right
to develop, use, market, promote, and sell a topical formulation of lidocaine in
a gel formulation ("Development Product"), whether sold over-the-counter or by
prescription, for human use which falls within the claims of the Licensed
Patents. HIND expects the clinical development for the Development Product to be
completed and its NDA subsequently filed by the end of calendar year 1999.
Within six (6) months of the Product Launch, ENDO shall complete its due
diligence on the Development Product. Within one (1) month of the completion of
ENDO's due diligence on the Development Product, ENDO may exercise the option
granted by HIND under this Paragraph. In the event ENDO exercises its option
under this Paragraph, ENDO shall bear all reasonable costs for the completion of
the NDA, including any applicable filing fees, provided that all such activities
are under ENDO's general supervision and such reasonable costs do not exceed
HIND's anticipated development and NDA filing budget of One Million Dollars
($1,000,000). Any reasonable expense over and beyond the budget approved by ENDO
for the Development Product, must receive prior written approval from ENDO. In
the event that ENDO fails to exercise its option under this Paragraph in the
time provided herein, all of HIND's rights to the Development Product shall
remain with HIND to do as it may decide.

7.2  ***.

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VIII.  WARRANTIES AND REPRESENTATIONS
       ------------------------------

8.1    Legal Authority.  Each party represents and warrants to the other that it
       ---------------
has the legal power, authority and right to enter into this Agreement and to
perform its respective obligations set forth herein.

8.2    No Conflicts.  Each party represents and warrants that as of the date of
       ------------
this Agreement it is not a party to any agreement or arrangement with any third
party or under any obligation or restrictions, which in any way limits or
conflicts with its ability to fulfill any of its obligations under this
Agreement.

8.3    Third Party Claims.  HIND warrants to ENDO that there are no third party
       ------------------
claims that would challenge or impair the license of the rights granted to ENDO
herein, including without limitation, any claims based upon patents, copyrights,
trademarks, or trade secret laws of the Territory.  In the event, that a bono
fide third party claim manifests itself with regard to the Intellectual Property
and ENDO is able to negotiate an appropriate royalty bearing license from such
third party, HIND shall pay fifty percent (50%) of such third party royalty,
provided that in no event shall HIND be required to pay more than fifty percent
(50%) of the royalties paid by ENDO to HIND hereunder.  To the extent that the
royalty due to the third party exceeds 12% per annum, ENDO shall have the option
to terminate this Agreement.

8.4    Submission Package.  HIND hereby warrants and represents to ENDO that the
       ------------------
Submission Package for the Product and all information contained therein, as of
the effective date of this Agreement, are true and correct and that HIND is
unaware of any fact that would render such information inaccurate or untrue .

8.4    Survival.  The foregoing representations and warranties shall survive the
       --------
execution, delivery, and performance of this Agreement, notwithstanding any due
diligence investigation by or on behalf of either party.

IX.    TRADEMARKS
       ----------

9.1.   Trademark License Grant.  HIND hereby grants ENDO an exclusive, royalty-
       -----------------------
free right and license, subject to Paragraph 4.3 above, to use the Trademark in
connection with the marketing, promotion, advertising, and sale or other
distribution of the Product in the Territory. ENDO may sublicense such right and
license to use such Trademark to any permitted sublicensees if such sublicensee
agrees in writing to be bound by the terms and conditions of this Paragraph.

9.2    ENDO may request HIND's reasonable assistance, at the expense of ENDO, in
applying for or maintaining any registration of the Trademark in the Territory.

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9.3    HIND shall notify ENDO at least sixty (60) days prior to abandoning the
registration for the Trademark to allow ENDO to maintain such registration if it
so chooses.

X.  INFRINGEMENT OF INTELLECTUAL PROPERTY RIGHTS BY THIRD PARTIES
    -------------------------------------------------------------

10.1   In the event that any infringement of any aspect of the Intellectual
Property Rights shall come to the attention of HIND or ENDO, HIND or ENDO shall
duly inform each other, and ENDO shall, in its sole discretion, determine
whether or not HIND should prosecute an infringement action in connection with
such Rights, provided that if ENDO so elects that HIND should initiate legal
proceedings against the alleged infringer, such proceedings shall be at ENDO's
expense, subject to the provisions of this Agreement.  HIND hereby agrees to
work with ENDO in the initiation and prosecution of any such Intellectual
Property Rights infringement proceedings.

10.2   ENDO may deduct the expenses of any such proceedings against up to fifty
percent (50%) of the Royalty, if any due to HIND from ENDO, including minimum
royalties, under this Agreement.  Out of any damages or awards recovered by HIND
in such action, HIND will first recover all royalties up to the 50% of Royalty
payable by ENDO to HIND and withheld by ENDO to defray costs of such
proceedings.  ENDO will then recover its expenses for conducting said litigation
beyond the costs defrayed by the withheld royalties.  HIND will also recover any
expenses, which it incurred on behalf of the litigation.  Any amount remaining
thereafter belongs to ENDO.  Sales made by the infringer shall be treated as a
sale made by ENDO for Royalty purposes under this Agreement.

XI. CONFIDENTIAL INFORMATION
    ------------------------

11.1   All information disclosed by one party to the other under this Agreement
shall be deemed to be confidential information ("Confidential Information").
The parties hereby agree to hold in strictest confidence any and all
Confidential Information disclosed by one party to the other under this
Agreement or obtained by either party as a result of performing its obligations
under this Agreement.  The parties hereby agree that the following shall not be
considered Confidential Information subject to this Agreement:

(a) information which at the time of disclosure by one party to the other is in
    the public domain;

(b) information which, after disclosure by one party to the other becomes part
    of the public domain by publication or otherwise, provided that such
    publication is not in violation of this Agreement or any other
    confidentiality agreement;

(c) information, which the receiving party can establish in writing, was
    already known to it or was in its possession at the time of disclosure by
    the other party and was not acquired, directly or indirectly, from the
    disclosing party.

(d) information, which the receiving party lawfully receives from a third
    party, provided, however, that such third party was not obligated to hold
    such information in confidence.

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(e)  information which the receiving party is compelled to disclose by a court
     or other tribunal of competent jurisdiction, or the FDA, provided however,
     that in each such case the receiving party shall immediately give notice to
     the disclosing party to enable the disclosing party to exercise its legal
     rights to prevent and/or limit such disclosure. In any event, the receiving
     party shall disclose only that portion of the Confidential Information
     that, in the opinion of the disclosing party's legal counsel, is legally
     required to be disclosed and will exercise reasonable efforts to ensure
     that any such information so disclosed will be accorded confidential
     treatment by said court or tribunal.

11.2   The receiving party shall not use Confidential Information for any
purpose other than for the purposes set forth in this Agreement.

11.3.  The receiving party will not disclose Confidential Information to any
person other than to its employees, officers, agents, and consultants that have
a need to know such information to effectuate the purpose of this Agreement and
that only if employees, officers, agents, and consultants shall be informed of
this Confidentiality Agreement and shall, in writing, be bound by its terms.
All Confidential Information will contain a statement indicating that the
information is confidential and should not be disclosed to unauthorized
individuals.

11.4   Upon written request from the disclosing party or termination of this
Agreement, whichever comes sooner, the receiving party shall either promptly
return to the disclosing party all Confidential Information provided to the
receiving party pursuant to this Agreement, including any copies thereof and
notes or extracts based thereon or certify to the disclosing party that all such
Confidential Information have been duly destroyed; except the receiving party
may keep one (1) copy for archival purposes and until this Agreement is
terminated or becomes inoperative, shall keep confidential and not use in any
way detrimental to the disclosing party any analyses, compilation, studies or
other documents which reflect any of the Confidential Information.

XII. RECORDS
     -------

ENDO shall keep accurate books and accounts of records in connection with the
sale of the Product in the Territory in sufficient detail to permit accurate
determination of the amount of royalties to be paid by ENDO to HIND.  Such
records shall be maintained for a period of two (2) years from the end of the
License Year in which sales occurred.  HIND, at its expense, through an
independent certified public accountant, shall have the right to access such
books and records for the sole purpose of verifying the royalty calculations;
such access shall be conducted after reasonable prior notice by HIND to ENDO
during ENDO's ordinary business hours and shall not be more frequent than once
per License Year.  Said accountant shall not disclose to HIND or any other party
any information except that which should properly be contained in a royalty
report required under this Agreement.  Any underpaid or overpaid royalties shall
be credited to the appropriate party within thirty (30) days after notice of and
agreement regarding such under or over payment.  Any under payment will be
subject to compounded interest at the rate of one percent (1%) per month and any
over payment shall bear an interest rate equal to the prime rate for the period
in which such overpayment relates to.

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XIII. TERM
      -----

This Agreement and the license granted to the Intellectual Property Rights
hereunder, shall expire upon the shorter of thirteen (13) years from the
Approval Letter or the expiration of the last to expire Licensed Patent.
Thereafter, ENDO shall have a fully paid up license to use all Intellectual
Property Rights to develop, use, market, promote, and sell the Product in the
Territory

XIV.  TERMINATION
      -----------

This Agreement may be terminated by either HIND or ENDO for the following
reasons:

(a)   Material Breach. Either party may terminate this Agreement in the case of
      ---------------
      a material breach by the other party which is not cured within forty-five
      (45) days after written notice of the breach by the terminating party

(b)   Bankruptcy.  Either party may terminate this Agreement immediately in its
      ----------
      entirety if the other party is declared insolvent by a court of competent
      jurisdiction, files a petition of bankruptcy, is adjudged bankrupt, takes
      advantage of any insolvency act, is in receivership, or executes a bill of
      sale, deed of trust, or assignment for the benefit of creditors.

(c)   ENDO may terminate this Agreement immediately upon termination of the
      Related Agreement.

XV.   EFFECT OF TERMINATION
      ---------------------

Upon termination of this Agreement pursuant to Article 14, all rights in the
development, importation, use, marketing, promotion, or sale of Product shall
revert to HIND, apart from any intellectual property that belongs exclusively to
ENDO.

XVI.  EFFECT OF TERMINATION ON OTHER OBLIGATIONS
      ------------------------------------------

Termination of this Agreement shall have no effect on, or relieve any party from
the obligation to make any payment or perform any actions arising prior to the
effective date of termination.

XVII. ARBITRATION
      ------------

17.1  All disputes over the meaning and interpretation of this Agreement shall
be resolved by conciliation and non-binding mediation and if such mediation is
unsuccessful then such disputes shall be finally settled by a single Arbitrator
selected by HIND and ENDO.  If HIND and ENDO cannot agree on a single
Arbitrator, then disputes shall be resolved by an Arbitration Panel comprising
one arbitrator appointed by HIND and one arbitrator appointed by ENDO, and a
Chairman of the Arbitration Panel appointed by the first two arbitrators.  Any
such arbitration proceeding shall be conducted in accordance with AAA rules;
shall be held in the Commonwealth of Pennsylvania, unless otherwise agreed by
the parties; and judgment upon the arbitration award may be entered in any court
having jurisdiction.

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17.2   In order to initiate procedures for dispute resolution by conciliation,
mediation and arbitration either party may give written notice to the other of
intention to resolve a dispute, and absent satisfactory resolution, then to
arbitrate.  Such notice shall contain a statement setting forth the nature of
the dispute and the resolution sought.  If, within thirty (30) days of such
notice a resolution by conciliation between the parties themselves or by
mediation has not been achieved to the satisfaction of both parties, and if
within forty-five (45) days from said written notice an Arbitrator or
Arbitration Panel has not been appointed with an arbitration schedule
satisfactory to both parties, then either party may proceed with judicial
remedies.

17.3   Notwithstanding the above, HIND reserves the right and power to proceed
with direct judicial remedies against ENDO without conciliation, mediation or
arbitration for material breach of the royalty payment and sales reporting
provisions of this Agreement after giving written notice of such breach to ENDO
followed by an opportunity period of forty-five (45) days in which to cure such
breach.  In collecting overdue royalty payments and securing compliance with
reporting obligations, HIND may use all judicial remedies available.

XVIII. OTHER
       -----

ENDO agrees that it will not use the indicia or name HIND or any of HIND's
personnel in advertising, promotion, or labeling of Products without prior
written approval of HIND.

XIX.   INDEMNIFICATION
       ---------------

(a)    ENDO hereby defends, indemnifies and holds HIND harmless from and against
       all liability, demands, damages, expenses or losses for death, personal
       injury, illness or property damage (including reasonable attorneys' fees)
       arising out of the marketing, promotion, and/or sale of the Product in
       the Territory. As used in this clause, HIND includes its Affiliates,
       officers, agents and employees, and "ENDO" includes its Affiliates,
       officers, agents, and employees.

(b)    HIND hereby defends, indemnifies and holds ENDO harmless from and against
       all liability, demands, damages, expenses or losses for death, personal
       injury, illness or property damage (including reasonable attorneys' fees)
       arising out of the breach of any of HIND's representations and warranties
       under this Agreement. As used in this clause, ENDO includes its
       Affiliates, officers, agents, and employees.

XX.    ASSIGNMENT
       ----------

Neither party may assign its rights and obligations under this Agreement without
the prior written consent of the other party, which will not be unreasonably
withheld, provided, however, that ENDO may assign its rights and obligations
hereunder to its successor in business and/or any subsidiary or parent entity,
provided that ENDO shall remain liable.

                                      12

<PAGE>

HIND-ENDO
SOLE AND EXCLUSIVE LICENSE AGREEMENT

XXI.  FORCE MAJEURE
      -------------

No party shall be liable for a delay in performance or failure to perform an
obligation under this Agreement if such delay or failure is due to an act of God
or any other occurrence beyond the control of the party, including but not
limited to fire, explosion, disease, war, invasion, government acts, weather or
civic unrest, or strikes, provided, however, that the party who is unable to
perform its obligations under this Agreement due to such occurrence resumes its
performance as soon as possible following the end of the occurrence causing
delay or failure.  In the event that a party claims non-performance of its
obligations under this Agreement as a result of this Paragraph, the other party
shall have the right to terminate this Agreement if the force majeure that is
claimed results in non performance by the claiming party that last more than
ninety (90) days.

XXII. NOTICE
      ------

All notices and other communications required or permitted hereunder shall be in
writing and shall be deemed to have been given when hand delivered or sent via a
facsimile machine or within five (5) business days of being mailed by registered
or certified United States mail or sent by courier to the following addresses:

                         Harry W. Hind
                         President
                         Hind Health Care, Inc.
                         Suite 101, 3707 Williams Road
                         San Jose, CA  95117-2017

                         with a copy to:

                         Larry Caldwell
                         Consulting Research Director
                         Hind Health Care, Inc.
                         Suite 101, 3707 Williams Road
                         San Jose, CA  95117-2017
                         and to ENDO:

                         Carol A. Ammon
                         President & CEO
                         Endo Pharmaceuticals Inc.
                         223 Wilmington West Chester Pike
                         Chadds Ford, PA  19317
                         Tel: (610) 558-9800
                         Fax: (610) 558-9683

                         With a copy to:

                         Osagie O. Imasogie
                         Senior Vice President, Business Development

                                      13

<PAGE>

HIND-ENDO
SOLE AND EXCLUSIVE LICENSE AGREEMENT

                         Endo Pharmaceuticals Inc.
                         223 Wilmington West Chester Pike
                         Chadds Ford, PA  19317
                         Tel: (610) 558-9800
                         Fax: (610) 558-9684

XXIII. GOVERNING LAW
       -------------

This Agreement shall be interpreted under the laws of the Commonwealth of
Pennsylvania, not taking into consideration its conflicts of laws.

XXIV.  ENTIRE AGREEMENT
       ----------------

This Agreement, together with its attached Exhibits, constitute the entire
agreement between HIND and ENDO with respect to the subject matter hereof and
supersedes all prior and/or contemporaneous agreements and understandings,
whether oral, written or in any other medium, that might exist between the
parties with relation to the subject matter hereof.  No modification to any
provision of this Agreement shall be binding unless in writing and signed by
both HIND and ENDO.  No waiver of any rights under this Agreement, will be
effective unless in writing signed by the party to be charged.  All of the terms
and provisions of this Agreement shall be binding upon and inure to the benefit
of and be enforceable by the respective successors and permitted assigns of the
parties hereto.

XXV.   PUBLICITY:
       ---------

HIND shall not originate any publicity, news release, or other public
announcement or comment, written or oral, relating to the Product and/or this
Agreement, without the prior written consent of ENDO, except for such
announcement which is required by law.  In the event HIND needs to make any
announcement which is required by law, it will provide ENDO a reasonable
opportunity to review the form and content of such announcement and comment upon
it before it is made public.

IN WITNESS WHEREOF, the parties hereto have caused this instrument to be
executed in duplicate as of the day and year first above written by their duly
authorized officers as set forth below.

HIND HEALTH CARE, INC.              ENDO PHARMACEUTICALS INC.

     /s/ HARRY W. HIND                   /s/ CAROL A. AMMON
By:  __________________________     By:  _________________________
          Harry W. Hind                       Carol A. Ammon
          President                           President & CEO

                                      14

<PAGE>

HIND-ENDO
SOLE AND EXCLUSIVE LICENSE AGREEMENT

EXHIBIT A

                                             PATENTS
                                             -------

U.S. Patent Number                 Title                            Issue Date
--------------------               -----                            ----------

5,709,869             "Method for Treating Nerve Injury               1/20/98
                      Pain Associated with Shingles"

5,411,738             "Method for Treating Nerve Injury                5/2/95
                      Pain Associated with Shingles
                      Herpes-Zoster and Post-Herpetic
                      Neuralgia) by Topical Application
                      Of Lidocaine"

5,601,838             "Method for Treating Pain Associated with       2/11/97
                      Herpes Zoster and Post-Herpetic Neuralgia"

5,589,180             "Method for Treating Nerve Injury              12/31/96
                      Pain Associated with Shingles (Herpes-Zoster
                      and Post Herpetic Neuralgia) by Topical
                      Application of Lidocaine"

                                   TRADEMARKS
                                   ----------

U.S. Trademark Registration number      Trademark           Registration Date
------------------------------------    ---------           -----------------

1597110                                 LIDODERM(R)         July 8, 1996
1821958                                 TAKON(R)            February 15, 1994

                                      15

<PAGE>

HIND-ENDO
SOLE AND EXCLUSIVE LICENSE AGREEMENT

EXHIBIT B

       SUPPLY AND MANUFACTURING AGREEMENT BETWEEN TEIKOKU SEIYKAKU CO.,
                       TEIKOKU PHARMA USA, INC. AND ENDO

                                      16

<PAGE>

HIND-ENDO
SOLE AND EXCLUSIVE LICENSE AGREEMENT

EXHIBIT C

                       NDA OWNERS' STATUTORY OBLIGATIONS

--------------------------------------------------------------------------------
21 CFR 314.                        CONTENT SUMMARY
--------------------------------------------------------------------------------
70           . Changes to the drug substance (i.e., synthesis, source, relax
               specification limits)
             . Changes to the drug product (i.e., add an ingredient, change
               manufacturing site, container/closure change)
             . Changes to the product labeling
--------------------------------------------------------------------------------
72           Change in ownership/sponsorship of the NDA
--------------------------------------------------------------------------------
80           . 15-day "Alert reports"
             . Periodic adverse drug experience reports (quarterly intervals for
               the first 3 years and annual thereafter)
--------------------------------------------------------------------------------
81           . NDA - Field alert report (quality concerns)
             . Annual Report
             . Advertisements and promotional labeling
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
PDUFA        User Fee for approved NDAs (Product Fee)*

--------------------------------------------------------------------------------

       *
             -------------------------------------------------------
                       1998      1999      2000      2001
             -------------------------------------------------------
                      $***      $***      $***      $***
             -------------------------------------------------------

                                      17<PAGE>

                                                                   EXHIBIT 10.11

                          ANALGESIC LICENSE AGREEMENT
                          ---------------------------

          This Analgesic License Agreement (the "Agreement") dated the 27th day
of October, 1997 (the "Effective Date"), is entered into by and among The DuPont
Merck Pharmaceutical Company ("DuPont Merck"), a Delaware general partnership,
and Endo Laboratories, L.L.C. ("Endo"), a subsidiary of DuPont Merck (Endo and
DuPont Merck together are referred to herein as "Licensor"), and Endo
Pharmaceuticals Inc., a Delaware corporation ("Licensee").

                              W I T N E S S E T H
                              -------------------

          WHEREAS, Licensor and Licensee are parties to that certain Asset
Purchase Agreement dated June 27, 1997, by and among DuPont Merck, DuPont Merck
Pharma, Endo and Licensee (the "Asset Purchase Agreement"); and

          WHEREAS, in connection with the transactions contemplated by the Asset
Purchase Agreement, Licensor desires to grant to Licensee an exclusive,
worldwide license with respect to the Patent Rights (as defined below) and Know-
How (as defined below), and Licensee desires to receive such license;

          NOW THEREFORE, in consideration of the foregoing and of the covenants
herein contained, intending to be legally bound, Licensor and Licensee hereby
covenant and agree as follows:

1.   Definitions
     -----------

     1.1  "Confidential Information" means certain secret and proprietary
           ------------------------
     information and documents relating to the Patents and Know-How licensed
     hereunder or relating to or held by any of the parties hereto, and
     includes, without limitation, compounds, intermediates, designs, formulas
     and formulations, methods, processes, know-how, and all other confidential
     scientific, clinical, regulatory, marketing, financial and commercial
     information or data, marketing strategies, product plans, plans for
     research, development and experimental research, test and safety data,
     supplier lists and all information relating to any Licensed Product,
     whether communicated in writing or orally (to be confirmed in writing
     within ten (10) days) or by other means, which is

<PAGE>

     provided or supplied by one party to the other party in connection with
     this Agreement.

     1.2  "Know-How" means information, materials, methods and practices,
           --------
     including but not limited to, preclinical, clinical, toxicological,
     regulatory, manufacturing, safety and pharmacological information which on
     the Effective Date of this Agreement are in Licensor's possession or
     control, are not generally known to the public and are necessary or useful
     for Licensee in the development, manufacture, use or sale of any Licensed
     Product. Know-How shall not include any such data or information which is
     available to Licensor under a license pursuant to which Licensor does not
     have the right to grant sublicenses.

     1.3  "Licensed Compounds" means individually and collectively the
           ------------------
     following:

          (i)   the selective kappa agonist compound referred to within DuPont
          Merck as DuP 747, published as: P. Rajagopalan, R.M Scribner, P.
          Pennev, W.K. Schmidt, S.W. Tam, G.F. Steinfels, and L. Cook, "DuP 747:
          A New, Potent, Kappa Opioid Analgesic. Synthesis and Pharmacology",
          Bioorganic & Medicinal Chemistry Letters, Vol. 2, No. 7, pp. 715-720
          (1992);

          (ii)  the nalbuphine prodrug referred to with in DuPont Merck as DuP
          769, published as: W.K. Schmidt, B.J. Aungst, G.A. Boswell, Jr., C.M.
          Maciag, M.E. Marynowski, H.F. Stampfli, G.F. Steinfels, A. Sunshine,
          and L. Cook, "Nalbuphine N-Oxide Prodrug: Analgesia and Nalbuphine
          Serum Levels Following Administration of DuP 769 in Rats and Dogs",
          Monograph No. 132: Problems of Drug Dependence, 1992: Proceedings of
          the 54th Annual Scientific Meeting, The College on Problems of Drug
          Dependence, Inc., pp. 147;

          (iii) the compound referred to within DuPont Merck as DuP 631,
          published as Y.N. Wong, D.L. Burcham, S.M. Huang, and C.Y. Quon,
          "Metabolism and Disposition of Exp 631-A Novel Antidepressant
          Analgesic", Biopharmaceutics and Drug Disposition, Vol. 14, pp. 519-
          531 (1993); and

                                       2
<PAGE>

          any active metabolite, prodrug, stereoisomeric, crystalline and/or
          salt forms thereof, provided however, that Licensed Analgesic
          Compounds shall not include nalbuphine.

     1.4  "Licensed Product" means a formulation for human pharmaceutical use in
           ----------------
     dosage form containing one or more Licensed Compounds.

     1.5  "Patent Rights" means the patents and patent applications listed on
           -------------
     Schedule A hereto and any and all patents and patent applications owned by
     or licensed to Licensor as of the Effective Date, which contain one or more
     claims covering any Licensed Product and/or Licensed Compound, or any
     method for synthesis or use thereof, and any and all divisions,
     continuations, and continuations-in-part thereof, and any reissues,
     renewals, reexaminations, extensions or the like of any such patents and
     patent applications and all foreign equivalents of any of the foregoing.
     Patent Rights shall not include any patents or patent rights available to
     Licensor under a license pursuant to which Licensor does not have the right
     to grant sublicenses.

2.   Grant.  Licensor hereby grants to Licensee an exclusive, worldwide, fully
     -----
paid-up, irrevocable license (collectively being the "Licensed Rights"), under
the Patent Rights and Know-How to attempt to make, make, have made, import, use,
offer for sale and sell Licensed Compounds and Licensed Products. The foregoing
grant shall include the right to sue for past infringement, and also the right
to grant exclusive and/or non-exclusive sublicenses to third parties, at
Licensee's sole discretion. The foregoing grant shall be exclusive as to
everyone, including Licensor. It shall be understood, however, that Licensor
retains all rights under the Patent Rights to all compounds and inventions
claimed therein except with respect to Licensed Compounds and Licensed Products.

3.   Delivery.  Licensor shall disclose and make available to Licensee, as soon
     --------
as possible but in no event later than thirty (30) days after the Effective
Date, copies of all Know-How embodied in tangible form, in any media, whether
electronic, written or otherwise. Such disclosure shall, as far as reasonably
practicable, be made in writing by furnishing copies of relevant materials.
Licensor shall also, as soon as possible but in no event later than thirty (30)
days after the Effective Date, deliver to the recipient designated by Licensee
any and all quantities of Licensed Compounds and Licensed Products which on the
Effective Date are in Licensor's possession or control.

                                       3
<PAGE>

4.   Term.  The license to the Patent Rights hereunder shall commence upon the
     ----
Effective Date and continue on a country-by-country basis until the expiration
of the last to expire of the Patent Rights in such country. The license to the
Know-How hereunder shall be perpetual. Notwithstanding the foregoing, the
licenses granted in Section 2 hereof will terminate if Licensee shall cease to
carry on business or shall go into liquidation or a receiver shall be appointed
to Licensee's assets, except in the case where Licensee has assigned this
Agreement in accordance with Section 8.3 below.

5.   Patent Maintenance and Patent Infringement
     ------------------------------------------

     5.1  Patent Maintenance.  Licensor shall be responsible for prosecuting and
          ------------------
     maintaining the Patent Rights. In meeting such responsibility, Licensor
     shall rely on its staff attorneys or outside counsel to the same extent it
     usually does in prosecuting similar patents and patent applications owned
     by Licensor. Licensor acknowledges its obligation to pay all maintenance
     fees and annuities as they become due and payable to the U.S. Patent and
     Trademark Office and other patent offices throughout the world, in order to
     avoid premature expiration of any of the Patent Rights. In the event that
     Licensor does not wish to continue to prosecute and/or maintain any of the
     Patent Rights, Licensor shall inform Licensee of such decision in writing
     as soon as practicable and Licensee shall have the right, but not the
     obligation, to take such steps itself at its own expense.

     5.2  Notice of Infringement.  Each party shall immediately give notice to
          ----------------------
     the other of (i) any potential infringement or actual infringement by a
     third party of any Patent Rights or any misappropriation of Know-How of
     which it becomes aware, or (ii) any certification of which it becomes aware
     filed under the United States "Drug Price Competition and Patent Term
     Restoration Act of 1984" claiming (x) that Patent Rights covering any
     Licensed Product are invalid or unenforceable or (y) that infringement will
     not arise from the manufacture, use or sale of Licensed Product by a third
     party.

     5.3  Licensee's Right to Bring Suit. With respect to any infringement of
          ------------------------------
     the Licensed Rights with respect to any Licensed Compound and/or Licensed
     Product, Licensee shall have the exclusive right, in its discretion, to
     settle with the infringer or to bring suit or other proceeding at its
     expense against the infringer. Licensee shall keep Licensor advised at all
     times of such suit or proceedings brought by Licensee. Licensor agrees to
     cooperate with Licensee

                                       4
<PAGE>

     in its efforts to protect the Patent Rights, including joining as a party
     where necessary. Licensee agrees to prosecute diligently any litigation it
     initiates under this Section 5.3. Licensee shall retain the full amount of
     any recovery hereunder, after reimbursing Licensor for its out-of-pocket
     expenses in connection with its participation in such suit or proceeding.

     5.4  Licensee Accused of Infringement.  In the event that Licensor or
          --------------------------------
     Licensee receives notice that a suit or other proceeding has been
     instituted against Licensee, claiming that by exercising the Patent Rights
     with respect to any Licensed Compound and/or Licensed Product Licensee is
     infringing or has infringed the intellectual property of a third party,
     each party shall notify the other of the same.

     5.5  Patent Term Extension.  The parties hereto shall cooperate with each
          ---------------------
     other in obtaining patent term extension or supplemental protection
     certificates or their equivalents in any country applicable to the Patent
     Rights, as follows: The parties will notify each other within five (5)
     business days of receiving approval for any Licensed Product from the U.S.
     Food & Drug Administration or its equivalent in any country. The parties
     will promptly negotiate in good faith extension strategies that would
     permit both parties to take maximum advantage of extensions for all Patent
     Rights hereunder.

6.   Indemnification and Warranties
     ------------------------------

     6.1  Indemnification.  Licensee hereby indemnifies and holds Licensor
          ---------------
     harmless from any and all claims of personal injury or property damage
     which may result from the manufacture, use or sale of any Licensed Products
     or Licensed Compounds.

     6.2  Warranties.  Licensor represents and warrants that it has sole and
          ----------
     exclusive right, title and interest in and to the Patent Rights; that it
     has not entered into any other agreement that would conflict with this
     Agreement; that it has the full legal right to grant the licenses provided
     hereunder; that it has not granted rights in or to the Patent Rights or the
     Know-How with respect to the Licensed Compounds to any person other than
     Licensee; that no patent search has been conducted to ascertain whether the
     exercise of the Licensed Rights will infringe any patent rights owned by
     third parties; and to the best of its knowledge, the exercise of the
     Licensed Rights will not infringe any third-party patent rights and neither
     the Patent Rights nor the

                                       5
<PAGE>

     Know-How have been limited due to Licensor's not having the right to grant
     sublicenses. Licensor hereby indemnifies and holds harmless Licensee from
     all damages (including attorneys' fees) arising from any breach of the
     foregoing representations and warranties.

     6.3  No Other Warranties.  LICENSOR MAKES NO OTHER WARRANTIES, EXPRESS OR
          -------------------
     IMPLIED, AS TO ANY MATTER WHATSOEVER, INCLUDING, WITHOUT LIMITATION, THE
     CONDITION, MERCHANTABILITY OR FITNESS FOR PURPOSE OF ANY PRODUCTS OR
     PROCESSES COVERED BY THE PATENT RIGHTS.

7.   Confidentiality
     ---------------

     7.1  Nondisclosure Obligation.  All Confidential Information hereunder
          ------------------------
     disclosed by one party to another, whether in the past or in the future,
     shall be governed by the terms and conditions of this Section 7. The
     parties hereto agree that all Confidential Information shall be maintained
     in confidence by the recipient and shall not be disclosed by the recipient
     to any other natural person, or any corporation, firm, partnership or other
     business entity, or any government or any agency thereof, without the prior
     written consent of the other party, except to the extent that such
     Confidential Information:

          (i)   is known by recipient at the time of its receipt as documented
          by business records;

          (ii)  is properly in the public domain through no fault of the
          receiving party;

          (iii) is subsequently disclosed to the receiving party by a third
          party who may lawfully do so and is not under an obligation of
          confidentiality to the disclosing party;

          (iv)  is developed by the receiving party independently of
          Confidential Information or other information received from the other
          party;

          (v)   is disclosed to governmental or other regulatory agencies in
          order to obtain patents or to gain approval to conduct clinical trials
          or

                                       6
<PAGE>

          to market Licensed Products, but such disclosure may be only to the
          extent reasonably necessary to obtain patents or authorizations;

          (vi)  is necessary or useful to be disclosed to prospective investors,
          sublicensees, agents, consultants and/or other third parties for the
          research and development, manufacturing, marketing and or sale of
          Licensed Products (or for such parties to determine their interest in
          performing such activities) in accordance with this Agreement on the
          condition that such third parties agree to be bound by the
          confidentiality obligations contained in this Agreement, provided that
          the term of confidentiality for such third parties shall be no less
          than five (5) years from the date of disclosure; or

          (vii) is required to be disclosed by law or court order, provided that
          notice is promptly delivered to the other party in order to provide an
          opportunity to challenge or limit the disclosure obligations.

     The receiving party shall use the same level of care, but no less than a
     reasonable level of care, to prevent the use or disclosure of Confidential
     Information received under this Agreement, as it exercises in protecting
     its own secret and proprietary information of similar nature. The receiving
     party shall only communicate Confidential Information to its employees,
     legal and financial advisors who need to know such Confidential
     Information, who have been previously made aware of the terms of this
     Agreement pertaining to Confidential Information and who have agreements
     with the receiving party obligating them to keep confidential such
     Confidential Information.

     7.2  Use of Confidential Information.  Both parties agree that the
          -------------------------------
     Confidential Information shall only be used in connection with the exercise
     of the parties' respective rights and the fulfillment of their obligations
     under this Agreement.

8.   Miscellaneous
     -------------

     8.1  This Agreement shall be construed in accordance with the laws of the
     United States and the laws of the State of Delaware, without regard for
     principles of conflicts of law thereof.

                                       7
<PAGE>

     8.2  This Agreement contains the entire and only agreement between the
     parties, and supersedes all preexisting oral or written agreements between
     them regarding the subject matter hereof. Any changes or modifications
     hereto shall be effective only if made in writing and signed by both
     parties.

     8.3  The rights of Licensee under this Agreement shall not be transferred
     or assigned without the consent of Licensor, which consent shall not be
     unreasonably withheld, except such that such rights may be assigned or
     transferred to a successor to Licensee's business through the sale of all
     or substantially all of Licensee's assets and/or shares, or merger or
     reorganization, without the consent of Licensor.

     8.4  In the event that any provision of this Agreement is held invalid or
     unenforceable in any circumstance by a court of competent jurisdiction, the
     remainder of this Agreement, and application of such provision in any other
     circumstances, shall not be affected thereby.

     8.5  The headings of this Agreement are for convenience of reference only
     and shall not affect the meaning or interpretation of this Agreement in any
     way.

     8.6  Each party hereto is an independent contractor and neither the making
     of this Agreement nor the performance of any of the provisions hereof shall
     be construed to make one party an agent, employee or legal representative
     of another party for any purpose, nor shall this Agreement be deemed to
     establish a joint venture or partnership.

     8.7  The failure of either party to assert a right hereunder or to insist
     upon compliance with any term or condition of this Agreement shall not
     constitute a waiver of that right or excuse a similar subsequent failure to
     perform any such term or condition by the other party.

     8.8  This Agreement may be executed in two or more counterparts, and when
     each party has signed and delivered at least one counterpart, each
     counterpart shall be deemed an original, and, when taken together with
     other signed counterparts, shall constitute one Agreement, which shall be
     binding upon and effective as to all parties.

                                       8
<PAGE>

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

THE DUPONT MERCK PHARMACEUTICAL COMPANY

      /s/ PAUL G. HOWES
By:  _____________________________________
     Name:  Paul G. Howes
     Title: President, CEO

ENDO LABORATORIES, L.L.C.

      /s/ PAUL G. HOWES
By:  _____________________________________
     Name:  Paul G. Howes
     Title: President, CEO

ENDO PHARMACEUTICALS INC.

     /s/ CAROL AMMON
By:  _____________________________________
     Name:  Carol Ammon
     Title: President, CEO

                                       9
<PAGE>

DuPont Legal Patent Division

License Agreement:  NorthStar & Endo Pharmaceuticals DuP 631 Exhibit A

27 October 1997

Page 1

<TABLE>
<CAPTION>
Docket Number      Country Name     Appl. Date        Applic. Number  Patent Number    Sub Sta    Abandon Date    Grant Date
<S>                <C>              <C>               <C>               <C>            <C>        <C>             <C>
BP6333             PHILIPPINES      21 Mar 1989       38357                            EPP
BP6333             DENMARK          22 Mar 1989       89/001456                        EPP
BP6333             KOREA SOUTH      28 Mar 1989       89/003866                        EPP
BP6333             JAPAN            28 Mar 1989       89/074129                        EPP
BP6333             U.S.A.           28 Mar 1988       07/174356                        ABN        01 Dec 1989
BP6333             NORWAY           22 Mar 1989       89/001260                        ABN        22 Oct 1994
BP6333             TAIWAN           24 Mar 1989       78102254          052941         ISS                        01 Apr 1992
BP6333             EUR PATENT       22 Mar 1989       89105083.3        0337167        ISS                        03 Aug 1994
BP6333             BELGIUM          22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             FRANCE           22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             GREAT BRITAIN    22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             ITALY            22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             LUXEMBOURG       22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             NETHERLANDS      22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             SPAIN            22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             SWEDEN           22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             SWITZERLAND      22 Mar 1989       UNKN              0337167        ISS                        03 Aug 1994
BP6333             GREECE           22 Mar 1989       940402613         3013326        ISS                        03 Aug 1994
BP6333             GERMANY          22 Mar 1989       P68917185.4-08    68917185       ISS                        03 Aug 1994
BP6333             AUSTRIA          22 Mar 1989       UNKN              E0109465       ISS                        03 Aug 1994
BP6333             HUNGARY          28 Mar 1989       89/001532         213671         ISS                        05 Aug 1997
BP6333             FINLAND          28 Mar 1989       89/001473         94240          ISS                        10 Aug 1995
BP6333             PORTUGAL         28 Mar 1989       90127             90127          ISS                        13 Dec 1993
BP6333             AUSTRALIA        28 Mar 1989       89/031717         623637         ISS                        15 Sep 1992
BP6333             ISRAEL           27 Mar 1989       89746             89746          ISS                        16 Jun 1993
</TABLE>

                                       10
<PAGE>

<TABLE>
<CAPTION>
Docket Number      Country Name     Appl. Date        Applic. Number    Patent Number  Sub Sta    Abandon Date    Grant Date
<S>                <C>              <C>               <C>               <C>            <C>        <C>             <C>
BP6333             RUSSIAN FED      27 Mar 1989       4613736/04        1836346        ISS                        24 Jan 1992
BP6333             CANADA           22 Feb 1989       591753            1337418        ISS                        24 Oct 1995
BP6333             SOUTH AFRICA     22 Mar 1989       89/002171         89/002171      ISS                        28 Nov 1990
BP6333             NEW ZEALAND      23 Mar 1989       228479            228479         ISS                        29 Apr 1992
BP6333             MEXICO           28 Mar 1989       015430            183916         ISS                        30 Jan 1997
BP6333             MALAYSIA         27 Mar 1989       PI8900381         MY103990A      ISS                        30 Oct 1993
BP6333             IRELAND          23 Mar 1989       89/000913         65811          ISS                        31 Oct 1995
BP6333A            U.S.A.           28 Aug 1989       07/398999         5019650        ISS                        28 May 1991
BP6333B            U.S.A.           28 Aug 1989       07/398996         5086063        ISS                        04 Feb 1992
</TABLE>

                                       11
<PAGE>

DuPont Legal Patent Division

License Agreement:  NorthStar & Endo Pharmaceuticals DuP 747 Exhibit A

27 October 1997

Page 1

<TABLE>
<CAPTION>
Docket Number      Country Name     Appl. Date        Applic. Number    Patent Number  Sub Sta    Abandon Date    Grant Date
<S>                <C>              <C>               <C>               <C>            <C>        <C>             <C>
BP6322             U.S.A.           10 Sep 1986       905543                           ABN        01 Jan 1989
BP6322A            PHILIPPINES      10 Sep 1987       35798                            EPP
BP6322A            CANADA           08 Sep 1987       546354                           EPP
BP6322A            AUSTRALIA        10 Sep 1987       87/078224         607935         ISS                        01 Aug 1991
BP6322A            ISRAEL           09 Sep 1987       83842             83842          ISS                        02 Oct 1991
BP6322A            MALAYSIA         10 Sep 1987       PI8701624         MY101368A      ISS                        05 Sep 1991
BP6322A            DENMARK          09 Sep 1987       87/004700         169071         ISS                        08 Aug 1994
BP6322A            IRELAND          09 Sep 1987       87/002406         60423          ISS                        08 Jul 1994
BP6322A            KOREA SOUTH      10 Sep 1987       87/010028         107765         ISS                        15 Nov 1996
BP6322A            HUNGARY          09 Sep 1987       87/004018         198016         ISS                        19 Apr 1989
BP6322A            PORTUGAL         09 Sep 1987       85668             85668          ISS                        20 Nov 1989
BP6322A            JAPAN            09 Sep 1987       87/224204         2110963        ISS                        21 Nov 1996
BP6322A            EUR PATENT       05 Sep 1987       87113010.0        0260555        ISS                        22 Apr 1992
BP6322A            BELGIUM          05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            FRANCE           05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            GREAT BRITAIN    05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            ITALY            05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            LUXEMBOURG       05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            NETHERLANDS      05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            SPAIN            05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            SWEDEN           05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            SWITZERLAND      05 Sep 1987       UNKN              0260555        ISS                        22 Apr 1992
BP6322A            GREECE           05 Sep 1987       UNKN              3004962        ISS                        22 Apr 1992
BP6322A            GERMANY          05 Sep 1987       P3778463.3-08     3778463        ISS                        22 Apr 1992
BP6322A            AUSTRIA          05 Sep 1987       UNKN              E0075223       ISS                        22 Apr 1992
</TABLE>

                                       12
<PAGE>

<TABLE>
<CAPTION>
Docket Number      Country Name     Appl. Date        Applic. Number    Patent Number  Sub Sta    Abandon Date    Grant Date
<S>                <C>              <C>               <C>               <C>            <C>        <C>             <C>
BP6322A            RUSSIAN FED      09 Sep 1987       4203411/04        1582984        ISS                        23 Dec 1988
BP6322A            U.S.A.           16 Jul 1987       07/071028         4876269        ISS                        24 Oct 1989
BP6322A            FINLAND          09 Sep 1987       87/003896         88298          ISS                        26 Apr 1993
BP6322A            MEXICO           10 Sep 1987       008173            170515         ISS                        27 Aug 1993
BP6322A            NEW ZEALAND      08 Sep 1987       221726            221726         ISS                        28 Aug 1990
BP6322A            NORWAY           09 Sep 1987       87/003762         172934         ISS                        29 Sep 1993
BP6322A            SOUTH AFRICA     10 Sep 1987       87/006778         87/006778      ISS                        30 May 1989
BP6322A            TAIWAN           09 Sep 1987       76105341          031661         ISS                        31 Jul 1989
</TABLE>

                                       13
<PAGE>

DuPont Legal Patent Division

License Agreement:  NorthStar & Endo Pharmaceuticals DuP 769 Exhibit A

27 October 1997

Page 1

<TABLE>
<CAPTION>
Docket Number      Country Name     Appl. Date        Applic. Number    Patent Number  Sub Sta    Abandon Date    Grant Date
<S>                <C>              <C>               <C>               <C>            <C>        <C>             <C>
BP6295             U.S.A.           02 Dec 1985       803222            4722928        ABN        02 Aug 1995     02 Feb 1988
BP6295             JAPAN            01 Dec 1986       86/284459         1966196        ISS                        25 Aug 1995
BP6295 1           JAPAN            24 May 1993       93/121382         2017591        ISS                        19 Feb 1996
BP6295A            U.S.A.           01 Oct 1987       07/103213                        ABN        01 Aug 1989
BP6295B            U.S.A.           27 Jul 1989       07/391406         4990617        ISS                        05 Feb 1991
</TABLE>

                                       14

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00075-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00075-of-00352.parquet"}]]