WAIVER

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                                                                   Exhibit 10.54

                                     WAIVER

         This Waiver is made into as of November 8, 2004 (the "Waiver"), by and

between COMERICA BANK ("Bank"), and GENAISSANCE PHARMACEUTICALS, INC.

("Borrower").

                                    RECITALS

         Borrower and Bank are parties to that certain Loan and Security

Agreement dated as of September 30, 2003, as amended by a First Amendment to

Loan and Security Agreement dated as of March 16, 2004 (collectively, the

"Agreement"). At the request of Borrower, Bank desires to waive compliance by

Borrower of two provisions of the Agreement, to the extent set forth in this

Waiver.

         NOW, THEREFORE, the parties agree as follows:

         1. Bank waives compliance by Borrower of (i) Section 6.9 of the

Agreement for the period from August 31, 2004 through October 5, 2004 and (ii)

Section 6.8 for the period from the date hereof through November 30, 2004. By

December 23, 2004, Borrower shall report compliance with Section 6.8. This is

not a continuing waiver, and Borrower shall co