Exhibit 10.1

CONFIDENTIAL

Amendment #1 to the
Letter of Agreement between
SmithKline Beecham Corporation and
Quest Diagnostics Incorporated

Effective March 31, 2008

    1.        

The purpose of this Amendment #1 to the Letter of Agreement effective January 1,
2008 between SmithKline Beecham Corporation d/b/a GlaxoSmithKline and Quest
Diagnostics Incorporated (hereinafter the “LOA”) is to extend the term
referenced in section 2 of the LOA to the earlier of (i) May 31, 2008, or (ii)
the full execution of a new comprehensive Global Clinical Trials Agreement.

  2.

All other terms and conditions of the LOA shall remain in full force and effect.

  3.

The parties hereto agree to this Amendment #1 to the LOA by their authorized
signatures below.

 

SMITHKLINE BEECHAM CORPORATION   QUEST DIAGNOSTICS INCORPORATED                
          Paula M. Russella   Daniel P. Megronigle   Sourcing Group Manager  
Executive Director, Sales & Marketing                   Date   Date  

 

 

Letter of Agreement, Amendment #1

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