AMENDMENT NO. 2 TO THE DEVELOPMENT AND MANUFACTURING SERVICES AGREEMENT

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                                                                   Exhibit 10.18

                                                                           Lonza

                                 AMENDMENT NO. 2

                                        TO

              THE DEVELOPMENT AND MANUFACTURING SERVICES AGREEMENT

                              DATED 08 JANUARY 2004

                                     BETWEEN

                               LONZA BIOLOGICS ***

                                        AND

                          TRUBION PHARMACEUTICALS INC.

Re:

Schedule 2 - Services

Updated Stages

     Stage 1 ***

     Stage 2 ***

     Stage 8 ***

Schedule 2 - Services

New Stages

    Add Stage 16    ***

    Add Stage 17    ***

     Add Stage 18    ***

Schedule 3 - Price and Payment

     Updated Price and Payment Terms for Updated Stages and New Stages

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                                                                           Lonza

THIS AMENDMENT is made the 20 day July 2004

BETWEEN

1.    LONZA BIOLOGICS ***, the registered office of which is at *** ("LB") and

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

WHEREAS

A.    Customer and LB entered into a development and manufacturing services
     agreement dated 08 January 2004 ("the Agreement"), under which LB is
     required to perform Services relating to the Cell Line and the Product, as
     further described in the Agreement, and

B.    Customer would like LB to perform additional services under the Agreement,
     and

C.    LB is prepared to perform the additional services, and the parties wish to
     amend the Agreement accordingly and to make other revisions to the
     Agreement.

NOW THEREFORE it is agreed as follows:

     1. Amendments to Schedule 2, Stages 1, 2 and 8. Schedule 2 of the Agreement
shall be amended to revise Stage 1 (Fermentation Process Evaluation), Stage 2
*** and Stage 8 (Production of *** of cGMP Product at *** Scale), as follows:

          1.1 Stage 1 of Schedule 2 shall now read In its entirety as follows:

     STAGE 1 ***

     1.1   OBJECTIVES

     ***

     1.2   ACTIVITIES

     ***

     1.3   DELIVERABLES

               1.3.1 A report of activities for the shake flask and lab scale
     fermenter activities.

               1.3.2 A report of activities performed during virus testing of
     the ***.

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     1.4   TIMESCALE

     This stage may start upon creation of the *** Cell Line and receipt of the
*** Cell Line from the Customer. This stage shall be complete upon issue of the
report for the virus testing activities.

     It is estimated that this stage shall be complete *** from commencement.

     1.2 Stage 2 of Schedule 2 shall now read In its entirety as follows:

STAGE 2 ***

     2.1   OBJECTIVES

     ***

     2.2   ACTIVITIES

     ***

     2.3   DELIVERABLES

               2.3.1 A report of activities carried out under this Stage 2 as
     detailed in activity 2.2.6.

                2.3.2 A one (1) page summary report to the customer for each
     ampoule revival during the *** (activity 2.2.5).

     2.4   TIMESCALE

     Stage 2 may commence as soon as the selected PSS is available from Stage 1
of the Services.

     Stage 2 shall be complete with the issue of the report (activity 2.3.1) and
it is estimated that this report will be issued *** from the commencement of
Stage 2.

     It is estimated that the *** will be established *** from the commencement
of Stage 2.


                                        -2-

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     1.3 Stage 8 of Schedule 2 shall now read in its entirety as follows:

STAGE 8 ***

     8.1   OBJECTIVES

     ***

     8.2   ACTIVITIES

     ***

     8.3   DELIVERABLES

     ***

     8.4   TIMESCALE

     When the Customer and LB agree to the commencement of this Stage, this
stage may commence as soon as the *** is available for use and the Process
development activities and cGMP documents are complete.

     This stage shall be complete upon issue of the certificate of analysis for
the Batch of Product.

     It is estimated that Product will be delivered *** from commencement of the
Stage. If Customer requests in writing, the Product can be shipped in quara