EXHIBIT 10.23 August 1, 2005 Ms. Barbara Pifel Ms. Audrey Schwimmer Mr. Derek Spears Weill Medical College of Cornell University Office of Research & Sponsored Programs 1300 York Avenue, Room A-131 New York, NY 10021 Dr. Brij Saxena Weill Medical...

                                  EXHIBIT 10.23

August 1, 2005


Xx. Xxxxxxx Xxxxx
Xx. Xxxxxx Xxxxxxxxx
Xx. Xxxxx Xxxxxx
Xxxxx Medical College of Cornell University
Office of Research & Sponsored Programs
0000 Xxxx Xxxxxx, Xxxx X-000
Xxx Xxxx, XX 00000

Xx. Xxxx Xxxxxx
Xxxxx Medical College of Cornell University
000 Xxxx 00xx Xxxxxx, Xxxx 000
Xxx Xxxx, XX 00000

Re:       Sponsored Research Agreement between Marc Pharmaceuticals, Inc. and
Weill Medical College of Cornell University dated January 22, 2004 (the
"Agreement")

Dear Ladies and Gentlemen:

     This letter is to confirm our understanding that the second payment to be
made under the Agreement, pursuant to section 4.1 which provided that $187,500
shall be paid by July 1, 2005, shall be revised as follows: $50,000 shall be
paid by August 16, 2005, $68,750 shall be paid by September 16, 2005 and $68,750
shall be paid by October 16, 2005.

     We trust that the foregoing represents the understanding between us. Please
indicate your confirmation by signature and return of the enclosed copy.


Sincerely,


Marc Pharmaceuticals, Inc.

By: ______________________
Name:   Xxxxxx X. Xxxxx
Title:  CEO & President


We hereby confirm our agreement and understanding of the foregoing:

Weill Medical College of Cornell University

By: ________________________
Name:______________________
Title: _______________________