AMENDMENT No. 10 to THE DEVELOPMENT AND MANUFACTURING SERVICES AGREEMENT

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                                                                   Exhibit 10.26

                                AMENDMENT No. 10

                                       to

                        THE DEVELOPMENT AND MANUFACTURING
                                SERVICES AGREEMENT

                              Dated 08 January 2004

                                     Between

                               LONZA BIOLOGICS ***

                                       and

                           TRUBION PHARMACEUTICALS, INC.

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     THIS AMENDMENT No. 10 ("Tenth Amendment") is made the 20th day of December
2005 BETWEEN

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

     TRUBION PHARMACEUTICALS, 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 ("the Agreement") dated 08 January 2004, pursuant to which LB
agreed to provide Services to the Customer, 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 set out
in the Agreement, and

     D. The parties wish to amend the Agreement in accordance with Clause 13.5
thereto.

     NOW THEREFORE IT IS HEREBY AGREED as follows:

     1.0 Two new Stages, Stage 32 and Stage 33, shall be added to Schedule 2 of
the Agreement to read as follows:

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      32. "Stage 32 - ***

          32.1 Objective

     ***

          32.2 Activities

     ***

          32.3 Timescale

     This Stage may commence upon issue of the protocol.

     This Stage shall be complete with the issu