Exhibit 10.1

AGREEMENT OF APPOINTMENT AND JOINDER AND

AMENDMENT NO. 1 TO THE

SECOND AMENDED AND RESTATED RIGHTS AGREEMENT

This Agreement of Appointment and Joinder and Amendment No. 1 to the Amended and
Restated Rights Agreement dated as of October 27, 2003, by and between Cephalon,
Inc., a Delaware corporation with offices at 41 Moores Road, Frazer, PA 19355
(the “Company”), and StockTrans, Inc. (“StockTrans”), as the same may be amended
from time to time (the “Rights Agreement”), is entered into as of February 9,
2007 by and between the Company and American Stock Transfer & Trust Company, a
New York banking corporation with offices at 59 Maiden Lane, New York, NY 10038
(“AST”).

Capitalized terms used but not otherwise defined herein shall have the meanings
ascribed thereto in the Rights Agreement.

WHEREAS, pursuant to Section 21 of the Rights Agreement, the Company has removed
the Rights Agent, effective as of the close of business on February 9, 2007; and

WHEREAS, the Company is required by the terms of the Rights Agreement to appoint
a successor Rights Agent, and desires to appoint AST as successor Rights Agent;
and

WHEREAS, AST wishes to serve as successor Rights Agent; and

NOW, THEREFORE, intending to be legally bound, and in consideration of the
foregoing and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the Company and AST hereby agree as
follows:

1.             Appointment of Successor Rights Agent. The Company hereby
appoints AST as successor Rights Agent under the Rights Agreement effective
February 9, 2007.

2.             Joinder to Rights Agreement. AST hereby accepts such appointment
and agrees to serve as Rights Agent under the Rights Agreement effective
September 1, 2006, and to be bound by the terms of the Rights Agreement as if it
was an original signatory to such agreement. All references to the Rights Agent
contained in the Rights Agreement shall mean AST; likewise, all referenced to
StockTrans contained in the Rights Agreement shall mean AST.

3.             Amendment to Section 21 of the Rights Agreement.  Section 21 of
the Rights Agreement is hereby amended to provide that any successor Rights
Agent shall, at the time of its appointment as Rights Agent, have a combined
capital and surplus of at least $20,000,000, instead of $50,000,000 as currently
provided. The fifth (5th) sentence of Section 21 of the Rights Agreement shall
now read as follows:

“Any successor Rights Agent, whether appointed by the Company or by such a
court, shall be a corporation organized and doing business under the laws of the

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United States or the laws of any state of the United States or the District of
Columbia, in good standing, having an office in the Commonwealth of Pennsylvania
or the State of New York, which is authorized under such laws to exercise
corporate trust or stock transfer powers and is subject to supervision or
examination by federal or state authority and which has at the time of its
appointment as Rights Agent a combined capital and surplus of at least $20
million.”

4.             Amendment to Section 26 of the Rights Agreement. All references
to StockTrans contained in Section 26 of the Rights Agreement are hereby deleted
in their entirety and replaced with the following:

American Stock Transfer & Trust Company

59 Maiden Lane

New York, New York 10038

Attention: Corporate Trust Department

With a copy to:

American Stock Transfer & Trust Company

59 Maiden Lane

New York, New York 10038

Attention: General Counsel

4.             Except as expressly modified herein, the Rights Agreement shall
remain in full force and effect.

5.             This Agreement may be executed in one or more counterparts, each
of which shall together constitute one and the same document.

[SIGNATURES ON FOLLOWING PAGE]

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IN WITNESS WHEREOF, the parties hereto have executed this Agreement of
Appointment and Joinder and Amendment No. 1 to the Second Amended and Restated
Rights Agreement as of the date first above written.

CEPHALON, INC.

 

AMERICAN STOCK TRANSFER & TRUST COMPANY

 

 

 

 

 

 

By:

/s/ J. Kevin Buchi

 

By:

/s/ Herb Lemmer

 

 

 

 

 

 

 

Name:

J. Kevin Buchi

 

Name:

Herb Lemmer

 

 

 

 

 

 

 

Title:

Exec. Vice President & CFO

 

Title:

General Counsel

 

 

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