<PAGE>   1
                                                                   EXHIBIT 10.36

                    AMENDED AND RESTATED EMPLOYMENT AGREEMENT

         THIS AMENDED AND RESTATED EMPLOYMENT AGREEMENT (this "Agreement") is
made as of September 1, 2001 by Endo Pharmaceuticals Holdings Inc., a Delaware
corporation (the "Employer"), and Peter A. Lankau (the "Employee").

         WHEREAS, the Employer and the Employee entered into an employment
agreement, dated as August 11, 2000 (the "Original Employment Agreement");

         WHEREAS, the Employee and the Board of Directors of the Employer have
each determined that amending and restating the Original Employment Agreement is
advisable and desirable; and

         WHEREAS, the Board of Directors of the Employer has approved this
Agreement upon the terms set forth herein;

         NOW THEREFORE, in consideration of the premises and mutual agreements
contained herein, the parties, intending to be legally bound, agree as follows:

ARTICLE 1.        DEFINITIONS.

                  For the purposes of this Agreement, the following terms have
the meanings specified or referred to in this Article 1.

                  "AGREEMENT" means this Employment Agreement, including the
Exhibits hereto, as amended from time to time.

                  "BASIC COMPENSATION" means Salary and Benefits.

                  "BENEFITS" shall have the meaning set forth in Section 3.1(b).

                  "BOARD OF DIRECTORS" means the board of directors of the
Employer.

                  "CONFIDENTIAL INFORMATION" means any and all:

                  (a) trade secrets concerning the business and affairs of the
Employer, product specifications, data, know-how, formulae, compositions,
processes, designs, sketches, photographs, graphs, drawings, samples, inventions
and ideas, past, current, and planned research and development, current and
planned manufacturing or distribution methods and processes, customer lists,
current and anticipated customer requirements, price lists, market studies,
business plans, computer software and programs (including object code and source
code),


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computer software and database technologies, systems, structures, and
architectures (and related formulae, compositions, processes, improvements,
devices, know-how, inventions, discoveries, concepts, ideas, designs, methods
and information);

                  (b) information concerning the business and affairs of the
Employer (which includes historical financial statements, financial projections
and budgets, historical and projected sales, capital spending budgets and plans,
the names and backgrounds of key personnel, personnel training and techniques
and materials) however documented; and

                  (c) notes, analysis, compilations, studies, summaries, and
other material prepared by or for the Employer containing or based, in whole or
in part, on any information included in the foregoing.

         "CPI" means the Consumer Price Index-All Urban Consumers, Philadelphia
Region (1982-1984 = 100), as published by the United States Department of Labor.

         "DISABILITY" shall have the meaning set forth in Section 6.2.

         "EFFECTIVE DATE" means the date stated in the first paragraph of this
Agreement.

         "EMPLOYMENT PERIOD" shall have the meaning set forth in Section 2.2.

         "FISCAL YEAR" means the Employer's fiscal year, as it exists on the
Effective Date or as changed from time to time.

         "FOR CAUSE" shall have the meaning set forth in Section 6.3.

         "FOR GOOD REASON" shall have the meaning set forth in Section 6.4.

         "INCENTIVE COMPENSATION" shall have the meaning set forth in Section
3.2.

         "PERSON" means any individual, corporation (including any non-profit
corporation), general or limited partnership, limited liability company, joint
venture, estate, trust, association, organization, or governmental body.

         "POST-EMPLOYMENT PERIOD" shall have the meaning set forth in Article 8.

         "RENEWAL TERM" shall have the meaning set forth in Section 2.2.

         "SALARY" shall have the meaning set forth in Section 3.1(a).

ARTICLE 2.        EMPLOYMENT TERMS AND DUTIES.

                  SECTION 2.1 EMPLOYMENT. The Employer hereby employs the
Employee, and the Employee hereby accepts employment by the Employer, upon the
terms and conditions set forth in this Agreement.


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                  SECTION 2.2 TERM. Subject to the provisions of Article 6, the
initial term of the Employee's employment under this Agreement will be one (1)
year, beginning on the Effective Date and ending on the first anniversary of the
Effective Date (the "Initial Term"). The term of this Agreement may be renewed
by the Employee and the Employer for additional periods of one year (each, a
"Renewal Term"; the Initial Term together with all Renewal Terms, if any, are
hereinafter referred to as the "Employment Period").

                  SECTION 2.3 DUTIES. The Employee will have such duties as are
assigned or delegated to the Employee by the Chief Executive Officer, and will
initially serve as Senior Vice President, U.S. Business of the Employer. The
Employee will devote the Employee's business, time, attention, skill, and energy
to the business of the Employer, will promote the success of the Employer's
business, and will cooperate with the Chief Executive Officer and the Board of
Directors in the advancement of the best interests of the Employer. Nothing in
this Section 2.3, however, will prevent the Employee from engaging in additional
activities in connection with personal investments and community affairs that
are not inconsistent with the Employee's duties under this Agreement. It is
expressly understood and agreed that to the extent any such activities have been
conducted by the Employee prior to the Effective Date, the continued conduct of
such activities (or the conduct of activities similar in nature and scope
thereto) subsequent to the Effective Date shall not thereafter be deemed to be
inconsistent with the Employee's duties under this Agreement. The Employee
shall, from time to time, inform the Board of Directors of those additional
activities in which the Employee is engaged. If the Employee is elected as a
director of the Employer or as a director or officer of any of Employer's
subsidiaries, the Employee will fulfill the Employee's duties as such director
or officer without additional compensation.

                  SECTION 2.4 DIRECTOR'S AND OFFICER'S LIABILITY COVERAGE. The
Employer shall cause the Employee to be (a) indemnified as an officer and
director of the Employer or any of its affiliates, to the extent applicable, to
the maximum extent permitted by applicable law, and (b) covered by director's
and officer's liability insurance as may be in effect from time to time in
connection with the Employee serving as an officer and director of Employer or
any of its affiliates. The provisions of this Section 2.4 shall survive
termination of this Agreement for any reason.

ARTICLE 3.        COMPENSATION.

                  SECTION 3.1 BASIC COMPENSATION.

                  (a) SALARY. The Employee will be paid an annual salary of
$300,000, subject to adjustment as provided below (the "Salary"), which will be
payable in equal periodic installments according to the Employer's customary
payroll practices, but no less frequently than monthly. The Salary will be
reviewed by the Chief Executive Officer and the Board of Directors not less
frequently than annually, and be adjusted in the sole discretion of the Chief
Executive Officer and the Board of Directors, but in no event will the Salary be
less than $300,000 per year. In determining the amount of any adjustment to
Salary, the Chief Executive Officer and the Board of Directors shall take into
account inflation, merit, changes in responsibilities and industry salary
practices for executives. Any increase in Salary shall not serve to limit or
reduce


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any other obligation to the Employee under this Agreement. Salary shall
not be reduced after such increase unless such reduction is part of a reduction
in salaries of specified management personnel of the Employer undertaken in a
program approved by the Employer's Board of Directors.

                  (b) BENEFITS. The Employee will, during the Employment Period,
be permitted to participate in such incentive, savings, pension, profit sharing,
bonus, life insurance, hospitalization and major medical, and other employee
benefit plans, practices, policies and programs, of the Employer that may be in
effect from time to time, to the extent the Employee is eligible under the terms
of those plans (collectively, the "Benefits").

                  (c) STOCK OPTIONS. To the extent the Employer determines to
award stock options or other similar consideration to management personnel based
upon duration of employment or achieving performance targets, or both, Employee
shall be permitted to participate in such programs, and the Employer and the
Employee shall enter into an addendum to this Agreement outlining the terms of
such participation.

                  SECTION 3.2 INCENTIVE COMPENSATION. For each Fiscal Year or
part thereof during the Employment Period the Employee shall be paid in cash as
additional compensation (the "Incentive Compensation") for the services to be
rendered by the Employee pursuant to this Agreement, an amount equal to
forty-five percent (45%) of the Salary for such Fiscal Year (or such lesser
(including zero) or greater (not to exceed two hundred) percent of the Salary
for such Fiscal Year as is recommended in good faith to the Board of Directors
by the Chief Executive Officer of the Employer and approved by the Board of
Directors) if the Employer meets the performance targets set by the Board of
Directors (the "Performance Targets") for such Fiscal Year; provided, however,
that for Fiscal Year 2000 only, the Employer hereby guarantees to pay the
Employee his full Incentive Compensation in accordance with this paragraph.
Incentive Compensation for each Fiscal Year or part thereof shall be paid as
soon as practicable following the receipt by the Employer of its audited
financial statements for the Fiscal Year for which the Incentive Compensation is
being paid, unless the Employee shall elect to defer the receipt of such
Incentive Compensation.

ARTICLE 4.        FACILITIES AND EXPENSES.

                  The Employer will furnish the Employee office space,
equipment, supplies, and such other facilities and personnel as the Employer
deems necessary or appropriate for the performance of the Employee's duties
under this Agreement. The Employer will pay the Employee's dues in such
professional societies and organizations as are appropriate, and will pay on
behalf of the Employee (or reimburse the Employee for) reasonable expenses
incurred by the Employee at the request of, or on behalf of, the Employer in the
performance of the Employee's duties pursuant to this Agreement, and in
accordance with the Employer's employment policies, including reasonable
expenses incurred by the Employee in attending conventions, seminars, and other
business meetings, in appropriate business entertainment activities, and for
promotional expenses. The Employee must file expense reports with respect to
such expenses in accordance with the Employer's policies.




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ARTICLE 5.        VACATIONS AND HOLIDAYS.

                  The Employee will be entitled to paid vacation each Fiscal
Year in accordance with the vacation policies of the Employer in effect for its
executive officers from time to time, provided that in no event shall such
number of paid vacation days be fewer than twenty. Vacation must be taken by the
Employee at such time or times as approved by the Chief Executive Officer. The
Employee will also be entitled to the paid holidays and other paid leave set
forth in the Employer's policies. Vacation days and holidays during any Fiscal
Year that are not used by the Employee during such Fiscal Year may be used in
any subsequent Fiscal Year.




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ARTICLE 6.        TERMINATION AND ELECTION NOT TO RENEW.

                  SECTION 6.1 EVENTS OF TERMINATION. The Employment Period, the
Employee's Basic Compensation and Incentive Compensation, and any and all other
rights of the Employee under this Agreement or otherwise as an employee of the
Employer will terminate (except as otherwise provided in this Article 6):

                  (a)      upon the death of the Employee;

                  (b)      upon the disability of the Employee (as defined in
                           Section 6.2);

                  (c)      for cause (as defined in Section 6.3), immediately
                           upon notice from the Employer to the Employee, or at
                           such later time as such notice may specify, unless
                           otherwise provided in Section 6.3; or

                  (d)      for good reason (as defined in Section 6.4) upon not
                           less than thirty days' prior notice from the Employee
                           to the Employer.

                  SECTION 6.2 DEFINITION OF DISABILITY. For purposes of Sections
6.1 and 6.3, the Employee will be deemed to have a "disability" if, as a result
of the Employee's incapacity due to reasonably documented physical illness or
injury or mental illness, the Employee shall have been unable for more than six
months in any twelve month period to perform Employee's duties hereunder on a
full time basis and within 30 days after written notice of termination has been
give to the Employee, the Employee shall not have returned to the full time
performance of such duties. The date of termination in the case of a termination
for "disability" shall be the last day of the aforementioned 30-day period.

                  SECTION 6.3 DEFINITION OF "FOR CAUSE." For purposes of Section
6.1, the phrase "for cause" means: (a) the continued failure, after written
demand is delivered to the Employee which specifically identifies the failure,
by the Employee substantially to perform the Employee's duties under this
Agreement (other than any such failure resulting from "disability"), (b) the
engagement by the Employee in serious misconduct that has caused, or in the good
faith judgment of the Board of Directors may cause if not discontinued, material
harm (financial or otherwise) to the Employer or any of its subsidiaries, if any
(provided that with respect to misconduct that the Board of Directors determines
may cause material harm if not discontinued, a written demand is delivered to
the Employee specifically identifying the misconduct and the Employee continues
the misconduct), such material harm to include, without limitation, (i) the
disclosure of material secret or confidential information of the Employer or any
of its subsidiaries, if any, (ii) the debarment of the Employer or any of its
subsidiaries, if any, by the U.S. Food and Drug Administration or any successor
agency (the "FDA"), or (iii) the registration of the Employer or any of its
subsidiaries, if any, with the U.S. Drug Enforcement Administration of any
successor agency (the "DEA") to be revoked or an application with the DEA to be
denied, (c) the debarment of the Employee by the FDA, or (d) the continued
material breach by the Employee of this Agreement or the amended and restated
Stockholders Agreement, dated as of July 14, 2000, among the Employee, the
Employer and other parties named therein (the


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"Stockholder's Agreement") after written demand is delivered to the Employee
which specifically identifies the breach.

                  SECTION 6.4 DEFINITION OF "FOR GOOD REASON." For purposes of
Section 6.1, the phrase "for good reason" means any of the following: (a) the
Employer's material breach Section 2.4, 3.1 or 3.2 or of this Agreement or its
obligations under the Stockholder's Agreement for the benefit of Employee; or
(b) the assignment of the Employee without the Employee's consent to a position,
responsibilities, or duties of a materially lesser status or degree of
responsibility than the Employee's position, responsibilities, or duties at the
Effective Date.

                  SECTION 6.5 TERMINATION PAY. Effective upon the termination of
this Agreement, the Employer will be obligated to pay the Employee (or, in the
event of Employee's death, Employee's designated beneficiary as defined below)
only such compensation as is provided in this Section 6.5 or Section 6.6. For
purposes of this Section 6.5, the Employee's designated beneficiary will be such
individual beneficiary or trust, located at such address, as the Employee may
designate by notice to the Employer from time to time or, if the Employee fails
to give notice to the Employer of such a beneficiary, the Employee's estate.
Notwithstanding the preceding sentence, the Employer will have no duty, in any
circumstances, to attempt to open an estate on behalf of the Employee, to
determine whether any beneficiary designated by the Employee is alive or to
ascertain the address of any such beneficiary, to determine the existence of any
trust, to determine whether any person or entity purporting to act as the
Employee's personal representative (or the trustee of a trust established by the
Employee) is duly authorized to act in that capacity, or to locate or attempt to
locate any beneficiary, personal representative, or trustee.

                  (a) TERMINATION BY THE EMPLOYEE FOR GOOD REASON. If the
Employee terminates this Agreement for good reason, the Employer will (i) pay
(A) monthly to the Employee the Employee's Salary for the remainder of the
Employment Period or eighteen (18) months, whichever is longer, and (B) the
Employee's Incentive Compensation for the Fiscal Year during which the
termination is effective, prorated through the date of termination, provided
that the applicable Performance Targets are met, and (ii) continue to provide
the Employee with the Benefits for the remainder of the Employment Period or
eighteen (18) months, whichever is longer.

                  (b) TERMINATION BY THE EMPLOYER FOR CAUSE. If the Employer
terminates this Agreement for cause, the Employee will be entitled to receive
the Employee's Salary and Incentive Compensation prorated through the date such
termination is effective.

                  (c) TERMINATION UPON DISABILITY. If this Agreement is
terminated by either party as a result of the Employee's disability, as
determined under Section 6.2, the Employer will pay the Employee the Salary and
Incentive Compensation (if the applicable Performance Targets are met) through
the remainder of the calendar month during which such termination is effective
and the period until disability insurance benefits commence ("Disability
Coverage Commencement") under the disability insurance coverage furnished by the
Employer to the Employee. From and after Disability Coverage Commencement and
for eighteen (18)


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consecutive months thereafter, the Employer will make regular payments to the
Employee in the amount by which the Salary exceeds the Employee's disability
insurance benefits.

                  (d) TERMINATION UPON DEATH. If this Agreement is terminated
because of the Employee's death, the Employee will be entitled to receive the
Employee's Salary through the end of the calendar month in which the Employee's
death occurs, and Incentive Compensation (if the applicable Performance Targets
are met) for the Fiscal Year during which the Employee's death occurs, prorated
through the date of the Employee's death.

                  (e) BENEFITS. Unless otherwise specifically provided herein or
otherwise provided for in the Benefits, the Employee's accrual of, or
participation in plans providing for, the Benefits will cease at the effective
date of the termination of this Agreement, and the Employee will be entitled to
accrued Benefits pursuant to such plans only as provided in such plans.

                  SECTION 6.6 ELECTION NOT TO RENEW. If the Employee elects to
renew this Agreement for a Renewal Term, but the Employer does not, and the
Employer's election not to renew is not for cause, the Employee will be entitled
to receive, the Salary for the remainder, if any, of the calendar month in which
such termination is effective and for eighteen (18) consecutive calendar months
thereafter and the Benefits for eighteen (18) consecutive months after the date
of termination.

                  SECTION 6.7 ADJUSTMENTS FOR CPI. The amounts payable to the
Employee pursuant to Sections 6.5(a) and 6.6 shall be adjusted based on CPI
every twelve (12) months to account for changes in the cost of living.


ARTICLE 7.        NON-DISCLOSURE COVENANT.

                  SECTION 7.1 ACKNOWLEDGMENTS BY THE EMPLOYEE. The Employee
acknowledges that (a) during the Employment Period and as a part of the
Employee's employment, the Employee will be afforded access to Confidential
Information; and (b) public disclosure of such Confidential Information could
have an adverse effect on the Employer and its business.

                  SECTION 7.2 AGREEMENTS OF THE EMPLOYEE. In consideration of
the compensation and benefits to be paid or provided to the Employee by the
Employer under this Agreement, the Employee covenants as follows:

                  (a) During and following the Employment Period, the Employee
will hold in confidence the Confidential Information and will not disclose it to
any person except with the specific prior written consent of the Employer, as
otherwise may be required by law or legal process or except as otherwise
expressly permitted by the terms of this Agreement.

                  (b) If any information that the Employer deems to be a trade
secret is found by a court of competent jurisdiction not to be a trade secret
for purposes of this Agreement, such


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information will, nevertheless, be considered Confidential Information for
purposes of this Agreement. The Employee hereby waives any requirement that the
Employer submit proof of the economic value of any trade secret or post a bond
or other security.

                  (c) None of the foregoing obligations and restrictions applies
to any part of the Confidential Information that the Employee demonstrates was
or became generally available to the public other than as a result of a
disclosure by the Employee.

                  (d) Upon termination of this Agreement by either party, or
upon the request of the Employer during the Employment Period, the Employee will
return to the Employer all Confidential Information in the Employee's possession
or subject to the Employee's control, and the Employee may not retain any
copies, abstracts, sketches, or other physical embodiment of any of the
Confidential Information.

ARTICLE 8.        NON-COMPETITION AND NON-INTERFERENCE.

                  The Employee covenants that the Employee will not, directly or
indirectly during the Employment Period, except in the course of the Employee's
employment hereunder, and during the Post-Employment Period, directly or
indirectly manage, operate, control, or participate in the management,
operation, or control of, be employed by, associated with, or in any manner
connected with, lend the Employee's name to, or render services or advice to,
any third party or any business whose products compete in whole or in part with
the products of the Employer (disregarding any non-pain management products that
were not products promoted by the Employer during the last three years).

                  For purposes of this Article 8, the term "Post-Employment
Period" means the period beginning on the effective date of termination of the
Employee's employment hereunder and ending on the later to occur of (i) 18
months after the effective date of such termination or (ii) the date amounts
payable to Employee under Section 6.5 (a) and (c) and Section 6.6 are to have
been paid in full pursuant to this Agreement (provided that notwithstanding
anything in this Agreement to the contrary, such amounts are being timely paid
by the Employer).

                  If any covenant in this Article 8 is held to be unreasonable,
arbitrary, or against public policy, such covenant will be considered to be
divisible with respect to scope, time, and geographic area, and such lesser
scope, time, or geographic area, or all of them, as a court of competent
jurisdiction may determine to be reasonable, not arbitrary, and not against
public policy, will be effective, binding, and enforceable against the Employee.

ARTICLE 9.        GENERAL PROVISIONS.

                  SECTION 9.1 INJUNCTIVE RELIEF AND ADDITIONAL REMEDY. The
Employee acknowledges that the injury that would be suffered by the Employer as
a result of a breach of the provisions of this Agreement (including any
provision of Articles 7 and 8) would be irreparable and that an award of
monetary damages to the Employer for such a breach would be an inadequate
remedy. Consequently, the Employer will have the right, in addition to any other
rights it may have, to obtain injunctive relief to restrain any breach or
threatened breach or


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otherwise to specifically enforce any provision of this Agreement, and the
Employer will not be obligated to post bond or other security in seeking such
relief.

                  SECTION 9.2 ESSENTIAL AND INDEPENDENT COVENANTS. The covenants
by the Employee in Articles 7 and 8 are essential elements of this Agreement,
and without the Employee's agreement to comply with such covenants, the Employer
would not have entered into this Agreement or employed or continued the
employment of the Employee. The Employer and the Employee have independently
consulted their respective counsel and have been advised in all respects
concerning the reasonableness and propriety of such covenants, with specific
regard to the nature of the business conducted by the Employer.

                  If the Employee's employment hereunder expires or is
terminated, this Agreement will continue in full force and effect as is
necessary or appropriate to enforce the covenants and agreements of the Employee
in Articles 7 and 8.

                  SECTION 9.3 DUTY TO MITIGATE. The Employee shall not be
required to mitigate damages or the amount of any payment required under this
Agreement, nor shall the payments due the Employee hereunder be reduced or
offset by reason of any payments the Employee may receive from any other source.

                  SECTION 9.4 REPRESENTATIONS AND WARRANTIES BY THE EMPLOYEE.
The Employee represents and warrants to the Employer that the execution and
delivery by the Employee of this Agreement do not, and the performance by the
Employee of the Employee's obligations hereunder will not, with or without the
giving of notice or the passage of time, or both: (a) violate any judgment,
writ, injunction, or order of any court, arbitrator, or governmental agency
applicable to the Employee; or (b) conflict with, result in the breach of any
provisions of or the termination of, or constitute a default under, any
agreement to which the Employee is a party or by which the Employee is or may be
bound.

                  SECTION 9.5 WAIVER. The rights and remedies of the parties to
this Agreement are cumulative and not alternative. Neither the failure nor any
delay by any party in exercising any right, power, or privilege under this
Agreement will operate as a waiver of such right, power, or privilege, and no
single or partial exercise of any such right, power, or privilege will preclude
any other or further exercise of such right, power, or privilege or the exercise
of any other right, power, or privilege.

                  SECTION 9.6 BINDING EFFECT; DELEGATION OF DUTIES PROHIBITED.
This Agreement shall inure to the benefit of, and shall be binding upon, the
parties hereto and their respective successors, assigns, heirs, and legal
representatives, including any entity with which the Employer may merge or
consolidate or to which all or substantially all of its assets may be
transferred. The duties and covenants of the Employee under this Agreement,
being personal, may not be delegated.

                  SECTION 9.7 NOTICES. All notices, consents, waivers, and other
communications under this Agreement must be in writing and will be deemed to
have been duly given when (a) delivered by hand (with written confirmation of
receipt), (b) sent by telecopier (with written


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confirmation of receipt), provided that a copy is mailed by registered mail,
return receipt requested, or (c) when received by the addressee, if sent by a
nationally recognized overnight delivery service (receipt requested), in each
case to the appropriate addresses and telecopier numbers set forth below (or to
such other addresses and telecopier numbers as a party may designate by notice
to the other parties):

                  If to the Employer:  Endo Pharmaceuticals Inc.
                                       100 Painters Drive
                                       Chadds Ford, PA 19317
                                       Attention: Carol A. Ammon

                  If to the Employee:  100 Painters Drive
                                       Chadds Ford, PA 19317

                  SECTION 9.8 ENTIRE AGREEMENT; AMENDMENTS. This Agreement
contains the entire agreement between the parties with respect to the subject
matter hereof and thereof and supersedes all prior agreements and
understandings, oral or written, between the parties hereto with respect to the
subject matter hereof and thereof. This Agreement may not be amended orally, but
only by an agreement in writing signed by the parties hereto.

                  SECTION 9.9 GOVERNING LAW. This Agreement will be governed by
and construed under the laws of the State of Delaware without regard to
conflicts of laws principles.

                  SECTION 9.10 SECTION HEADINGS, CONSTRUCTION. The headings of
Sections in this Agreement are provided for convenience only and will not affect
its construction or interpretation. All references to "Section" or "Sections"
refer to the corresponding Section or Sections of this Agreement unless
otherwise specified. All words used in this Agreement will be construed to be of
such gender or number as the circumstances require. Unless otherwise expressly
provided, the word "including" does not limit the preceding words or terms.

                  SECTION 9.11 SEVERABILITY. If any provision of this Agreement
is held invalid or unenforceable by any court of competent jurisdiction, the
other provisions of this Agreement will remain in full force and effect. Any
provision of this Agreement held invalid or unenforceable only in part or degree
will remain in full force and effect to the extent not held invalid or
unenforceable.

                  SECTION 9.12 COUNTERPARTS. This Agreement may be executed in
one or more counterparts, each of which will be deemed to be an original copy of
this Agreement and all of which, when taken together, will be deemed to
constitute one and the same agreement.


                               [SIGNATURES FOLLOW]


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

                            ENDO PHARMACEUTICALS HOLDINGS INC.



                            By:  /s/ CAROL A. AMMON
                               -------------------------------------
                               Name:       Carol A. Ammon
                               Title:      President & Chief Executive Officer


                                /s/ PETER A. LANKAU
                               -------------------------------------
                               Peter A. Lankau




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