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                                                                    Exhibit 4.11

P. Herendeen Series B
Execution Copy

     SUPPLEMENTAL AGREEMENT NO. 1 TO WARNER CHILCOTT PUBLIC LIMITED COMPANY
                               WARRANT CERTIFICATE


            WHEREAS, PAUL HERENDEEN (the "Warrant Holder") is the holder of
certain warrants (the "Warrants") of Warner Chilcott Public Limited Company
("WC") as set forth in a Series B certificate dated June 28, 1996 (the "Warrant
Certificate");

            WHEREAS, on September 29, 2000 WC and Galen Holdings PLC ("Galen"),
consummated a change of control transaction (the "Acquisition") by means of a
scheme of arrangement under the laws of the Republic of Ireland (the "Scheme")
whereby Galen exchanged all of the outstanding securities of WC for ordinary
shares in Galen; and

            WHEREAS, unless otherwise defined herein, capitalized terms used
herein will have the meanings set forth in the Warrant Certificate.

            NOW THEREFORE, the parties agree as follows:

            1. Change in Number and Purchase Price of Warrants. Under the
Scheme, holders of warrants to purchase WC's American Depository Receipts
("ADR's"), evidencing WC's American Depository Shares ("ADS's") will, upon
exercise, receive ordinary shares of Warner Chilcott, each of which will
immediately be exchanged pursuant to the Scheme for 2.5 ordinary shares of
Galen, to be held in the form of Galen ADR's evidencing Galen ADS's. Each Galen
ADS currently represents four Galen ordinary shares. As a result, (a) each
holder of warrants to purchase WC ADR's will, upon such exercise and immediate
exchange, receive 0.625 Galen ADR's for each WC ADR, with fractions of ADR's
being rounded as appropriate, and (b) the effective purchase price for these
Galen ADR's shall be derived by dividing the Purchase Price of WC ADR's by
0.625. Therefore, the Warrant Certificate will hereinafter have the effect of
entitling the Warrant Holder to purchase 6250 Galen ADR's at a purchase price of
$32.00.

            2. Net Exercise. The following language shall be added to the end of
Section 2(c) of the Warrant Certificate:

            "IN LIEU OF PAYMENT OF THE PURCHASE PRICE AS SET FORTH IN THE FIRST
            SENTENCE OF THIS SECTION 2(c), THE WARRANT HOLDER MAY EXERCISE THIS
            WARRANT BY DELIVERING A NOTICE OF NET EXERCISE IN THE FORM OF
            EXHIBIT A HERETO ELECTING TO RECEIVE, WITHOUT CASH PAYMENT BY THE
            WARRANT HOLDER OF ANY ADDITIONAL CONSIDERATION, ORDINARY SHARES THAT
            WILL IMMEDIATELY BE EXCHANGED FOR GALEN ADR'S EQUAL TO THE VALUE OF
            THE WARRANTS (OR THE PORTION THEREOF BEING CANCELED) BY SURRENDER OF
            THIS WARRANT CERTIFICATE TOGETHER WITH THE FORM OF NET EXERCISE
            (ATTACHED HERETO AS EXHIBIT A) DULY EXECUTED, IN WHICH EVENT THE
            COMPANY SHALL ISSUE TO THE WARRANT HOLDER HEREOF (UPON THE IMMEDIATE
            EXCHANGE OF
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P. Herendeen Series B
Execution Copy

            ORDINARY SHARES PURSUANT TO THE SCHEME) A NUMBER GALEN ADR'S
            COMPUTED USING THE FOLLOWING FORMULA:

                                   X= Y (A-B)
                                     ---------
                                         A

            WHERE:      X= THE NUMBER OF GALEN ADR'S TO BE ISSUED TO THE WARRANT
                        HOLDER PURSUANT TO THIS NET EXERCISE;

                        Y= THE NUMBER OF GALEN ADR'S IN RESPECT OF WHICH THE NET
                        ISSUE ELECTION IS MADE;

                        A= THE FAIR MARKET VALUE OF ONE GALEN ADR AT THE TIME
                        THE NET ISSUE ELECTION IS MADE; AND

                        B= THE PURCHASE PRICE (AS ADJUSTED TO THE DATE OF THE
                        NET ISSUANCE) DIVIDED BY 0.625.

            FOR PURPOSES OF THIS SECTION 2(e), THE FAIR MARKET VALUE OF ONE
            GALEN ADR AS OF A PARTICULAR DATE SHALL BE DETERMINED BY USING THE
            AVERAGE OF THE CLOSING PRICES OF THE GALEN ADR'S TRADED ON THE
            NASDAQ NATIONAL MARKET (OR ANY SUCCESSOR UNITED STATES NATIONAL
            MARKET THE GALEN ADR'S TRADE ON) OVER THE TWENTY (20) DAY PERIOD
            ENDING THREE (3) DAYS PRIOR TO THE NET EXERCISE ELECTION."

            3. Deposit Agreement. The reference to "Deposit Agreement" in
Section 3 of the Warrant Certificate shall be amended so that it refers instead
to the Amended and Restated Deposit Agreement among WC, Galen and The Bank of
New York as Depositary, dated September 29, 2000.
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P. Herendeen Series B
Execution Copy



            IN WITNESS WHEREOF, the Company and Paul Herendeen have caused this
Supplemental Agreement No. 1 to be signed by their duly authorized signatories
and to be dated as of September 29, 2000.



WARNER CHILCOTT PUBLIC LIMITED COMPANY


By: /s/ Roger Boissonneault
   ------------------------------
Name:  Roger Boissonneault
Title: President and Chief Operating Officer



PAUL HERENDEEN

By: /s/ Paul Herendeen
   ------------------------------
Print Name:  Paul Herendeen
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P. Herendeen Series B
Execution Copy

EXHIBIT A


                             Notice of Net Exercise


            The undersigned ______________________________________, pursuant to
the provisions of the Warrant Certificate, hereby elects to exchange its Warrant
pursuant to Section 2(e) of the Warrant Certificate.


Dated:________________


Signature:____________________________
Name of Holder (Print):
Title:
Address: