MODIFIED BLOOD SCREENING INSTRUMENT ? eSAS 2 ADDENDUM AMENDING AGREEMENT ENTERED INTO AS OF JUNE 11, 1998

TABLE OF CONTENTS

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MODIFIED BLOOD SCREENING INSTRUMENT –

eSAS 2 ADDENDUM

This Modified Blood Screening Instrument — eSAS 2 Addendum (“eSAS 2 Addendum”) is entered into, effective as of January 1, 2002 (“Addendum Effective Date”) pursuant to and amending that certain Agreement entered into as of June 11, 1998 (“Agreement”) by and between Gen-Probe Incorporated, a Delaware corporation (“Gen-Probe”) with a principal place of business at 10210 Genetic Center Drive, San Diego CA 92121, and Chiron Corporation, a Delaware corporation (“Chiron;” Chiron and Gen-Probe each is individually referred to as  “Party” and collectively are referred to as the “Parties”) with a place of business at 4560 Horton Street, Emeryville, CA 94608.

Recitals

A.                                   The Parties entered into the Agreement as of June 11, 1998.  The Agreement was amended by the following: (i) June 11, 1998 Supplemental letter agreement, (ii) June 26, 1998 Addendum to Collaboration Agreement, (iii) June 30, 1998 Supplemental letter agreement, (iv) June 30, 1998 Consent, (v) December 7, 1999 Amendment to Collaboration Agreement, (vi) February 1, 2000 Amendment No. 2 to Collaboration Agreement, (vii) June 7, 2001 Supplemental agreement no. 1  (Customer training and Support), (viii) October 30, 2001 Confidentiality and Joint Interest Agreement, (ix) April 1, 2002 Amendment No. 3 (warehousing and shipping), (x) the Short Form Agreement dated November 16, 2001 and the Definitive Written Settlement Agreement dated December 5, 2001, (xi) the Future Blood Screening Assay – Ultrio Addendum dated as of January 1, 2002 (the “Ultrio Development Addendum”), (xii) March 5, 2003 Amendment No. 4 (Milestone for Ultrio on Tigris); (xiii) the Future Blood Screening Assay – WNV Addendum dated as of June 1, 2003 (the “Ultrio Development Addendum”) and (xiv) January 1, 2004 Amendment No. 5 (Applicable Purchase Price).

B.                                     In the Agreement, the Parties agreed to discuss, during the term thereof, the selection and establishment of one or more Development Programs for one or more Blood Screening Instruments.

C.                                     The Parties have discussed the proposed development of an eSAS 2 Instrument system, consisting of the following multiple modules: (i) a front end pipettor; (ii) an automated reagent addition station; (iii) an automated target capture bay; (iv) an automated incubation module; and (v) a data management to track sample and system interactions to meet customer demands of throughput and automation required for pooled donor screening by NAT.

D.                                    The Parties intend that the development of each module in the eSAS 2 Instrument system will provide improved automation or replacement of current aging or obsolete instrument components with newer technology, all without [***] the assay sensitivity or specificity; subject to all the terms and conditions of this eSAS 2 Addendum, the Parties will agree that each such module within the eSAS 2 Instrument system will be a modification to a “Blood Screening Instrument”, as provided in Section 3.3.7 of the Agreement.

E.                                      By this eSAS 2 Addendum, the Parties desire to provide for the development of the eSAS 2 Instrument by Chiron pursuant to the Agreement, as clarified and amended by the terms and conditions more particularly described in this eSAS 2 Addendum.

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Agreement