===============================================================================
                      SECURITIES AND EXCHANGE COMMISSION
                            Washington, D.C. 20549

                             ____________________


                                 SCHEDULE TO
                                (Rule 14d-100)
                Tender Offer Statement Under Section 14(d)(1)
          or Section 13(e)(1) of the Securities Exchange Act of 1934

                               Amendment No. 1

                             ____________________


                      ENDO PHARMACEUTICALS HOLDINGS INC.
                      (Name of Subject Company (Issuer))

                      ENDO PHARMACEUTICALS HOLDINGS INC.
                      (Name of Filing Persons (Offeror))

                             ____________________



                        CLASS A TRANSFERABLE WARRANTS
                      CLASS B NON-TRANSFERABLE WARRANTS
                        (Title of Class of Securities)

                             ____________________


                                  29264F114
                                  29264NTWT
                    (Cusip Number of Class of Securities)

                             ____________________


                         Caroline Berry Manogue, Esq.
             Senior Vice President, General Counsel and Secretary
                              100 Painters Drive
                       Chadds Ford, Pennsylvania 19317
                                (610) 558-9800

                    (Name, address and telephone number of
                     person authorized to receive notices
               and communications on behalf of filing persons)

                                   Copy to:
                            Eileen T. Nugent, Esq.
                   Skadden, Arps, Slate, Meagher & Flom LLP
                              Four Times Square
                              New York, NY 10036
                           Telephone: 212-735-3000


                          CALCULATION OF FILING FEE



Transaction Valuation*: $10,145,231.25        Amount of Filing Fee**: $2,029.05


*    Estimated for purposes of calculating the amount of the filing fee only.
     This calculation assumes the purchase of 13,500,000 Class A Transferable
     Warrants (the "Class A Warrants") and all outstanding Class B
     Non-Transferable Warrants (the "Class B Warrants" and, together with the
     Class A Warrants, the "Warrants"), at a price per Warrant of $0.75 in
     cash. As of December 3, 2001, there were 17,576,424 Class A Warrants and
     26,975 Class B Warrants outstanding. The amount of the filing fee,
     calculated in accordance with Rule 0-11 of the Securities Exchange Act
     of 1934, as amended, equals 1/50th of one percent of the value of the
     transaction.

**   Previously paid.

| |  Check the box if any part of the fee is offset as provided by Rule
     0-11(a)(2) and identify the filing with which the offsetting fee was
     previously paid. Identify the previous filing by registration statement
     number, or the Form or Schedule and the date of its filing.

     Amount previously paid:   Not applicable      Filing Party: Not applicable
     Form or registration no.: Not applicable      Date Filed: Not applicable

|    Check the box if the filing relates solely to preliminary communications
     made before the commencement of a tender offer. Check the appropriate
     boxes below to designate any transactions to which the statement
     relates:
| |  third-party tender offer subject to Rule 14d-1.
|X|  issuer tender offer subject to Rule 13e-4.
| |  going-private transaction subject to Rule 13e-3.
| |  amendment to Schedule 13D under Rule 13d-2.

Check the following box if the filing is a final amendment reporting the
results of the tender offer: | |

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        This Amendment No. 1 (this "Amendment") amends and supplements the
Tender Offer Statement on Schedule TO filed by Endo Pharmaceuticals Holdings
Inc., a Delaware corporation ("Endo") on December 5, 2001 (the "Schedule
TO"). The Schedule TO relates to an offer by Endo to purchase up to
13,500,000 of the issued and outstanding Class A Transferable Warrants (the
"Class A Warrants") and any and all of the issued and outstanding Class B
Non-Transferable Warrants (the "Class B Warrants" and, collectively with the
Class A Warrants, the "Warrants"), of Endo at a purchase price of $0.75 per
Warrant, net to the seller in cash, without interest thereon, upon the terms
and subject to the conditions set forth in the Offer to Purchase dated
December 5, 2001 (the "Offer to Purchase") and in the related Letter of
Transmittal (the "Letter of Transmittal"). A copy of the Offer to Purchase is
attached hereto as Exhibit (a)(1)(A), and a copy of the Letter of Transmittal
is attached hereto as Exhibit (a)(1)(C). The Offer to Purchase and Letter of
Transmittal, collectively, as they may be amended or supplemented from time
to time, constitute the "Offer".

        The information in the Offer to Purchase, including all schedules and
annexes thereto, is hereby expressly incorporated herein by reference in
response to all the items of this Schedule TO, except as otherwise set forth
below.


ITEM 4. TERMS OF THE TRANSACTION.

        Item 4 of the Schedule TO, which incorporates by reference the
information contained in the Offer to Purchase, is hereby amended as follows:

A.  The language ", 14d-4(c), 14d-6(d)" in the first sentence of the fourth
paragraph under the heading "The Offer--Terms of the Offer" on page 18 of the
Offer to Purchase is deleted, so that the first sentence of such paragraph
reads in its entirety:

        "Any extension, amendment or termination of the Offer will be
        followed as promptly as practicable by public announcement
        thereof, with such announcement in the case of an extension to be
        issued no later than 9:00 a.m., New York City time, on the next
        business day after the previously scheduled Expiration Date in
        accordance with Rules 13e-4(e) and 14e-1(d) under the Exchange
        Act."

B.  The phrase "Rule 13e-4(e) and" is inserted after the words "limited by"
in the last sentence of the fourth paragraph under the heading "The
Offer--Terms of the Offer" on page 18 of the Offer to Purchase, so that the
first sentence of such paragraph reads in its entirety:

        "However, the ability of the Company to delay the payment for
        Warrants that the Company has accepted for payment is limited by
        Rule 13e-4(e) and Rule 14e-1(c) under the Exchange Act, which
        require that a bidder pay the consideration offered or return the
        securities deposited by, or on behalf of, holders of securities
        promptly after the termination or withdrawal of the Offer."

C. The language ", 14d-4(c), 14d-6(d)" in the first sentence of the sixth
paragraph under the heading "The Offer--Terms of the Offer" on pages 18-19
of the Offer to Purchase is deleted, so that the first sentence of such
paragraph reads in its entirety:

        "If the Company makes a material change in the terms of the Offer
        or the information concerning the Offer or waives a material
        condition of the Offer, the Company will disseminate additional
        tender offer materials and extend the Offer to the extent required
        by Rules 13e-4(e) and 14e-1(e) promulgated under the Exchange
        Act."

D.  The phrase "Rule 14d-1" in the fifth sentence of the sixth paragraph
under the heading "The Offer--Terms of the Offer" on pages 18-19 of the
Offer to Purchase is deleted and replaced by the phrase " Rule 13e-4", so
that the fifth sentence of such paragraph reads in its entirety:

        "As used in this Offer to Purchase, 'business day' has the meaning
        set forth in Rule 13e-4 promulgated under the Exchange Act."

E.  The word "Rule" in the first sentence of the second paragraph under the
heading "The Offer--Conditions to the Offer" on page 25 of the Offer to
Purchase is deleted and replaced by the words "Rules 13e-4(e)(5) and", so
that the first sentence of such paragraph reads in its entirety:

        "Notwithstanding any other provisions of the Offer, and in
        addition to (and not in limitation of) Company's rights to extend
        and amend the Offer at any time in its sole discretion, the
        Company shall not be required to accept for payment or, subject to
        any applicable rules and regulations of the SEC, including Rules
        13e-4(e)(5) and 14e-1(c) under the Exchange Act (relating to the
        Company's obligation to pay for or return tendered Warrants
        promptly after termination or withdrawal of the Offer), pay for,
        and may delay the acceptance for payment of or, subject to the
        restriction referred to above, the payment for, any tendered
        Warrants, and may terminate or amend the Offer as to any Warrants
        not then paid for, if at any time before the scheduled expiration
        date of the Offer, any of the following events shall occur or
        shall have occurred:"

F.  The last paragraph under the heading "The Offer--Conditions to the Offer"
on page 26 is hereby amended and restated as follows:

        "The conditions listed above are for the sole benefit of the
        Company, and the Company may assert these conditions regardless of
        the circumstances that give rise to them, and may waive any of
        these conditions, in whole or in part, at any time and from time
        to time in its sole discretion, before the Expiration Date. The
        failure by the Company at any time to exercise any of the
        foregoing rights shall not be deemed a waiver of any such right
        and each such right shall be deemed an ongoing right which may be
        asserted at any time and from time to time before the Expiration
        Date."


ITEM 12. EXHIBITS.

Exhibit No.    Description
----------     -----------
(a)(1)(A)      Offer to Purchase dated December 5, 2001*
(a)(1)(C)      Letter of Transmittal.*
(a)(1)(D)      Notice of Guaranteed Delivery.*
(a)(1)(E)      Letter to Brokers, Dealers, Commercial Banks, Trust Companies
               and Nominees.*
(a)(1)(F)      Letter to clients for use by Brokers, Dealers, Commercial
               Banks, Trust Companies and Nominees.*
(a)(1)(G)      Press Release dated December 5, 2001*
(a)(1)(H)      Guidelines for Certification of Taxpayer Identification Number
               on Substitute Form W-9.*
(b)            None.
(c)            None.
(d)(1)(A)      Amended and Restated Executive Stockholders Agreement,
               dated as of July 14, 2000, by and among Endo, Endo
               Pharma LLC, Kelso Investment Associates V, L.P. ("KIA V"),
               Kelso Equity Partners V, L.P. ("KEP V") and the
               Management Stockholders (as defined therein).(1)
(d)(1)(B)      Amended and Restated Employee Stockholders Agreement,
               dated as of July 14, 2000, by and among Endo, Endo
               Pharma LLC, KIA V, KEP and the Employee Stockholders (as
               defined therein).(2)
(d)(1)(C)      Endo LLC Amended and Restated 1997 Employee Stock Option
               Plan.(3)
(d)(1)(D)      Endo LLC Amended and Restated 1997 Executive Stock Option
               Plan.(4)
(d)(1)(E)      Endo LLC 2000 Amended and Restated Supplemental Employee Stock
               Option Plan.(5)
(d)(1)(F)      Endo LLC 2000 Amended and Restated Supplemental Executive Stock
               Option Plan.(6)
(d)(1)(G)      Tax Sharing Agreement: dated as of July 17, 2000, by and among
               Endo, Endo Inc. and Endo Pharma LLC.(7)
(d)(1)(H)      Kelso Side Letter: Letter Agreement, dated as of
               November 26, 1999,
               by and among Algos, Endo, KIA V and KEP V.(8)
(d)(1)(I)      Registration Rights Agreement: dated as of July 17, 2000, by and
               between Endo and Endo Pharma LLC.(9)
(e)            None.
(f)            Not Applicable.
(g)            None.
(h)            None.


_______________

    *    Previously filed.

     (1)   Incorporated by reference to Exhibit 4.1 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter ended June 30, 2000 filed with the
           Commission on August 15, 2000.

     (2)   Incorporated by reference to Exhibit 4.2 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter ended June 30, 2000 filed with the
           Commission on August 15, 2000.

     (3)   Incorporated by reference to Exhibit 10.22 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter Ended September 30, 2000 filed with the
           Commission on November13, 2000.

     (4)   Incorporated by reference to Exhibit 10.23 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter Ended September 30, 2000 filed with the
           Commission on November 13, 2000.

     (5)   Incorporated by reference to Exhibit 10.24 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter Ended September 30, 2000 filed with the
           Commission on November 13, 2000.

     (6)   Incorporated by reference to Exhibit 10.25 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter Ended September 30, 2000 filed with the
           Commission on November 13, 2000.

     (7)   Incorporated by reference to Exhibit 10.5 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter ended June 30, 2000 filed with the
           Commission on August 15, 2000.

     (8)   Incorporated by reference to Exhibit 10.4 of Endo Pharmaceuticals
           Holdings' Registration Statement filed with the Commission on
           June 9, 2000.

     (9)   Incorporated by reference to Exhibit 4.4 of Endo
           Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
           for the Quarter ended June 30, 2000 filed with the
           Commission on August 15, 2000.







                                 SIGNATURE

      After due inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true, complete
and correct.


                                       ENDO PHARMACEUTICALS HOLDINGS INC.

                                       By:   /s/    CAROLINE B. MANOGUE
                                             --------------------------------
                                             Name:  Caroline B. Manogue
                                             Title: Senior Vice President,
                                                    General Counsel & Secretary






                               EXHIBIT INDEX


 Exhibit No.       Description
 -----------       -----------

 (a)(1)(A)         Offer to Purchase dated December 5, 2001*
 (a)(1)(C)         Letter of Transmittal.*
 (a)(1)(D)         Notice of Guaranteed Delivery.*
 (a)(1)(E)         Letter to Brokers, Dealers, Commercial Banks, Trust
                   Companies and Nominees.*
 (a)(1)(F)         Letter to clients for use by Brokers, Dealers, Commercial
                   Banks, Trust Companies and
                   Nominees.*
 (a)(1)(G)         Press Release dated December 5, 2001*
 (a)(1)(H)         Guidelines for Certification of Taxpayer Identification
                   Number on Substitute Form W-9.*
 (b)               None.
 (c)               None.
 (d)(1)(A)         Amended and Restated Executive Stockholders Agreement,
                   dated as of July 14, 2000, by and among Endo, Endo
                   Pharma LLC, Kelso Investment Associates V, L.P. ("KIA V"),
                   Kelso Equity Partners V, L.P. ("KEP V") and the
                   Management Stockholders (as defined therein).(1)
 (d)(1)(B)         Amended and Restated Employee Stockholders Agreement,
                   dated as of July 14, 2000, by and among Endo, Endo
                   Pharma LLC, KIA V, KEP and the Employee Stockholders (as
                   defined therein).(2)
 (d)(1)(C)         Endo LLC Amended and Restated 1997 Employee Stock
                   Option Plan. (3)
 (d)(1)(D)         Endo LLC Amended and Restated 1997 Executive Stock
                   Option Plan. (4)
 (d)(1)(E)         Endo LLC 2000 Amended and Restated Supplemental Employee
                   Stock Option Plan.(5)
 (d)(1)(F)         Endo LLC 2000 Amended and Restated Supplemental Executive
                   Stock Option Plan. (6)
 (d)(1)(G)         Tax Sharing Agreement: dated as of July 17, 2000, by and
                   among Endo, Endo Inc. and Endo Pharma LLC.(7)
 (d)(1)(H)         Kelso Side Letter: Letter Agreement, dated as of
                   November 26, 1999, by and among Algos, Endo, KIA V
                   and KEP V.(8)
 (d)(1)(I)         Registration Rights Agreement: dated as of July 17, 2000,
                   by and between Endo and Endo Pharma LLC.(9)
 (e)               None.
 (f)               Not Applicable.
 (g)               None.
 (h)               None.

______________

     *   Previously Filed

     (1)    Incorporated by reference to Exhibit 4.1 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter ended June 30, 2000 filed with the
            Commission on August 15, 2000.

     (2)    Incorporated by reference to Exhibit 4.2 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter ended June 30, 2000 filed with the
            Commission on August 15, 2000.

     (3)    Incorporated by reference to Exhibit 10.22 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter Ended September 30, 2000 filed with the
            Commission on November13, 2000.

     (4)    Incorporated by reference to Exhibit 10.23 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter Ended September 30, 2000 filed with the
            Commission on November 13, 2000.

     (5)    Incorporated by reference to Exhibit 10.24 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter Ended September 30, 2000 filed with the
            Commission on November 13, 2000.

     (6)    Incorporated by reference to Exhibit 10.25 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter Ended September 30, 2000 filed with the
            Commission on November 13, 2000.

     (7)    Incorporated by reference to Exhibit 10.5 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter ended June 30, 2000 filed with the
            Commission on August 15, 2000.

     (8)    Incorporated by reference to Exhibit 10.4 of Endo
            Pharmaceuticals Holdings' Registration Statement filed
            with the Commission on June 9, 2000.

     (9)    Incorporated by reference to Exhibit 4.4 of Endo
            Pharmaceuticals Holdings' Quarterly Report on Form 10-Q
            for the Quarter ended June 30, 2000 filed with the
            Commission on August 15, 2000.