Exhibit 24

POWER OF ATTORNEY

Each of the undersigned, hereby constitutes and appoints each of Charles A. Rowland Jr., Peter A.
Lankau and Caroline B. Manogue to be his or her true and lawful attorneys-in-fact and agents, with full power of each to act alone, and to sign for the undersigned and in each of their respective names in any and all capacities stated below, this
Annual Report on Form 10-K (and any amendments hereto) and to file the same, with exhibits hereto and thereto and other documents in connection herewith and therewith, with the Securities and Exchange Commission, hereby ratifying and confirming all
that each of said attorneys-in-fact, or his or her substitute or substitutes, may do or cause to be done by virtue hereof.

Pursuant to the requirements of
the Securities Exchange Act of 1934, this Power of Attorney has been signed by the following persons in the capacities and on the dates indicated.



|                                   |  |                                      |  |              
|---------------------------------- |  | ------------------------------------ |  | -------------
|Signature                          |  | Title                                |  | Date         
|                                   |  |                                     
|/S/ Carol A. Ammon                 |  |                                      |  |              
|Carol A. Ammon                     |  | Chairman                             |  | March 1, 2007
|                                   |  |                                     
|/S/ John J. Delucca                |  |                                      |  |              
|John J. Delucca                    |  | Director                             |  | March 1, 2007
|                                   |  |                                     
|/S/ Michel de Rosen                |  |                                      |  |              
|Michel de Rosen                    |  | Director                             |  | March 1, 2007
|                                   |  |                                     
|/S/ George F. Horner, III          |  |                                      |  |              
|George F. Horner, III              |  | Director                             |  | March 1, 2007
|                                   |  |                                     
|/S/ Michael Hyatt                  |  |                                      |  |              
|Michael Hyatt                      |  | Director                             |  | March 1, 2007
|                                   |  |                                     
|/S/ Roger H. Kimmel                |  |                                      |  |              
|Roger H. Kimmel                    |  | Director                             |  | March 1, 2007
|                                   |  |                                     
|/S/ Peter A. Lankau                |  |                                      |  |              
|Peter A. Lankau                    |  | Chief Executive Officer and Director |  | March 1, 2007
|                                   |  |                                     
|/S/ Clive A. Meanwell, M.D., Ph.D. |  |                                      |  |              
|Clive A. Meanwell, M.D., Ph.D.     |  | Director                             |  | March 1, 2007