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                                                                   EXHIBIT 10.10
                               December 11, 2000


Mr. Steve Rizzo
Endeavor Pharmaceuticals, Inc.
5501 New Centre Drive
Wilmington, NC 28403

         Re: Lease for University Corporate Center

Dear Steve:

         The following letter incorporates our agreement to amend the Lease
between University Corporate Center, LLC ("Landlord") and Endeavor
Pharmaceuticals, Inc. ("Endeavor") dated September 20, 1999. Except for the
amendments specifically set forth in this letter, all of the other terms and
conditions of the original Lease shall remain in full force and effect.

         Our agreed upon amendments follow:

         1.       Premises. The property described in the Lease as the
                  "Premises" will change from the original 2,550 rentable square
                  feet to 4,114 rentable square feet effective as of the date of
                  your signature on this letter. The sketch attached hereto
                  shall represent the new Premise.

         2.       Term. The lease shall be extended from September 20,2000 to
                  September 30, 2005. Provided, however, at any time after March
                  20, 2002 and provided that Endeavor is not in default under
                  the Lease, Endeavor may give six (6) months' notice of early
                  termination and, after such termination, shall have no further
                  obligations under this Lease except for obligations which may
                  have arisen as a result of non-performance prior to such
                  termination.

         3.       Base Rent. Base Rent shall continue to be $4,322.25 per month
                  until February 1, 2001. After February 1, 2001 and continuing
                  until termination of the Lease, the Base Rent shall be
                  $6,423.23 per month (as adjusted below) which reflects a
                  credit of $550.00 per month for the cost of Tenant
                  improvements. In the event of early termination as above,
                  Endeavor will not be entitled to any additional credits or
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Mr. Steve Rizzo
Endeavor Pharmaceuticals, Inc.
December 11, 2000
Page 2

                  refunds for Tenant improvements. All Tenants improvements
                  shall be property of Landlord. Beginning on September 20,
                  2001, Base Rent shall be increased by three percent (3%) and
                  such increase shall be continued on an annual basis thereafter
                  throughout the term of the Lease. All rental amounts shall be
                  paid directly to First Atlantic Properties as agent for
                  Landlord until written notification to the contrary.

         4.       Right of First Refusal. Paragraph 5 of the original Lease is
                  amended to change the space subject to the right of first
                  refusal from the 1,360 square foot space to a 4,561 square
                  foot space on the second floor of the Building currently
                  occupied by Greenpoint.

         I trust the above accurately reflects our understanding and if so,
please have Endeavor Pharmaceuticals, Inc. execute in the space below.

                           Very truly yours,

                           UNIVERSITY CORPORATE CENTER, LLC


                           By: /s/ Stewart Lyon
                              --------------------------------------


scm

AGREED UPON AND ACCEPTED THIS THE 20TH DAY OF DECEMBER, 2000.

                           ENDEAVOR PHARMACEUTICALS, INC.

                           By:  /s/ Steven F. Rizzo
                              --------------------------------------
                                    Steven F. Rizzo
                                    Vice President