Trubion Pharmaceuticals to present data on its TRU-016 product candidate at the ASH meeting

Trubion Pharmaceuticals, Inc. (Nasdaq: TRBN) announced today the acceptance of two data presentations on its product candidate, TRU-016, at the 2009 American Society of Hematology (ASH) Annual Meeting Dec. 5-8, 2009 in New Orleans, Louisiana. The presentations will include additional positive data from 1) an ongoing Phase 1 clinical trial of TRU-016 for the treatment of chronic lymphocytic leukemia (CLL), and 2) a preclinical study demonstrating the effect of Trubion's Tru-ADhanCe(TM) technology in promoting enhanced natural killer cell mediated cytotoxicity against primary CLL cells. TRU-016 is Trubion's novel CD37-targeted therapy for the treatment of B-cell malignancies and is being developed in collaboration with Facet Biotech Corporation.

Presentation 3424: A Phase 1 Trial of TRU-016, An Anti-CD37 Small Modular Immunopharmaceutical (SMIP(TM)) Protein in Relapsed and Refractory CLL: Early Promising Clinical Activity

Conclusions: To date, TRU-016 is a well-tolerated treatment with minimal infusional toxicity and the maximum tolerated dose (MTD) has not been reached. One partial response (PR) and a median reduction of 83% in peripheral lymphocytosis have been observed. Encouraging reduction in lymph node/spleen size and improvement in normal hematopoietic function in patients with high-risk genomic CLL have been observed at low doses of CD37. The protocol has been amended to explore higher saturating doses of CD37. Future single-agent and combination studies of TRU-016 in CLL are warranted.

Presentation 1744: Glycovariant CD37 Small Modular Immunopharmaceutical (Tru-ADhanCe(TM) SMIP) Promotes Enhanced Natural Killer Cell Mediated Cytotoxicity against Primary CLL Cells

Conclusions: Results of this study suggest that Tru-ADhanCe(TM) technology promotes enhanced natural killer cell mediated cytotoxicity against primary CLL cells and the potential use of Tru-ADhanCe versions of TRU-016 with enhanced antibody-dependent cell-mediated cytotoxicity (ADCC) function as an alternate for TRU-016 in B cell malignancies, including CLL therapy.

Copies of the TRU-016 abstracts are now available on ASH's website at http:// href="http://www.hematology.org/">www.hematology.org or Trubion's website at http://investors.trubion.com/events.cfm. Copies of the full data presentations will be available on Trubion's website after the data is presented at the 2009 ASH Annual Meeting.