February 21, 2008 Mr. Michael R. Dougherty Dear Mr. Dougherty,

Exhibit 10.20

February 21, 2008

Xx. Xxxxxxx X. Xxxxxxxxx

Dear Xx. Xxxxxxxxx,

This letter (this “Third Amendment”) will amend that certain letter agreement dated October 24, 2002, between you and Adolor Corporation (the “Company”) (the “Letter Agreement”), as amended January 26, 2004 (the “First Amendment”), as amended December 14, 2006 (the “Second Amendment”) a copy of the Letter Agreement, the First Amendment and the Second Amendment are appended to this letter as Exhibit A. The Letter Agreement, First Amendment, Second Amendment and this Third Amendment shall together constitute the “Agreement”).

Effective the date hereof, your target bonus shall be 55%.

Except as set forth in this Third Amendment, the Agreement shall remain in full force and effect.

Sincerely, ADOLOR CORPORATION
By:		/S/    X. X. XXXXXX
Name:		Xxxxx X. Xxxxxx
As its:		Chairman, Board of Directors

AGREED TO AND ACCEPTED

THIS 22nd DAY of February, 2008

/s/    X. X. Xxxxxxxxx                

Xxxxxxx X. Xxxxxxxxx