THE DEVELOPMENT AND MANUFACTURING SERVICES AGREEMENT

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                                                                   Exhibit 10.15

                                 AMENDMENT No. 2

                                       to

                        THE DEVELOPMENT AND MANUFACTURING
                                SERVICES AGREEMENT

                              Dated 12 AUGUST 2003

                                     Between

                               LONZA BIOLOGICS ***

                                       and

        TRUBION PHARMACEUTICALS, INC. (formerly known as GENECRAFT INC.)

Schedule 1 - Definitions and Specifications
Definition of term "Product"

Schedule 2 - Services
New Stages

Schedule 3 - Price and Payment
Price and Payment for New Stages

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     THIS SECOND AMENDMENT ("Second Amendment") is made the 2nd day of December,
2003

     BETWEEN

     LONZA BIOLOGICS *** (hereinafter referred to as "LB"), and

     TRUBION PHARMACEUTICALS, INC. (formerly known as GENECRAFT, INC.) of 2401
4th Avenue, Suite 1050, Seattle, WA 98121, USA (herein after referred to as the
"Customer")

     WHEREAS

     A. LB and the Customer entered into a development and manufacturing
services agreement dated 12 August 2003 pursuant to which LB agreed to provide
Services to the Customer (as amended by the Amendment No. 1 between the parties
dated November 7, 2003, "the Agreement"), and,

     B. The Customer now wishes LB to perform additional Services under the
Agreement, and,

     C. LB is willing to perform such additional Services on the terms to be
agreed upon by the parties and incorporated into the Agreement, and

     D. The parties wish to amend the Agreement in accordance with Clause 12.5
thereto.

     NOW THEREFORE IT IS HEREBY AGREED as follows:

     1 SCHEDULE 1 SHALL