Announced it has completed enrollment and dosing of patients in its Phase IIb clinical trial of TRU-015, the Company’s lead Small Modular ImmunoPharmaceutical (SMIP(TM)) drug candidate for the treatment of rheumatoid arthritis (RA).



SEATTLE, WA, USA |  Jan 16, 2007 |
Trubion Pharmaceuticals, Inc. (Nasdaq: TRBN), today announced it has completed enrollment and dosing of patients in its Phase IIb clinical trial of TRU-015, the Company’s lead Small Modular ImmunoPharmaceutical (SMIP(TM)) drug candidate for the treatment of rheumatoid arthritis (RA). The randomized, double-blind, placebo-controlled clinical trial is designed to evaluate safety and clinical response rates in patients with rheumatoid arthritis.

"We are pleased with the rapid enrollment of this study and look forward to reporting its results later this year," said Peter Thompson, M.D., co-founder, president and CEO of Trubion. "Previously reported TRU-015 clinical trial data has been promising and we expect that the results of our ongoing clinical evaluation will serve as the basis for Phase III pivotal trial design."

TRU-015 Phase IIb Clinical Trial Protocol

The Phase IIb randomized, double-blind, placebo-controlled clinical trial is designed to enroll 280 patients with rheumatoid arthritis. Patients have been randomized into five groups to evaluate the safety and efficacy of an infused dose of TRU-015 compared to placebo for a 24-week period. Building on the findings of Trubion’s Phase IIa clinical trial, this trial will evaluate the effect of a single infusion of TRU-015 ranging from 200 mg to 1,600 mg per patient.

Similar to the Phase IIa study, this study will evaluate composite measurements of improvement in disease activity derived from parameters such as tender and swollen joint counts, patient and physician global assessments, patient assessment of pain and disability, and laboratory measures of inflammation as defined by the American College of Rheumatology.

About TRU-015 and SMIPs

Trubion and Wyeth Pharmaceuticals, a division of Wyeth (NYSE: WYE) are developing TRU-015, a SMIP(TM) drug candidate, as a potential new therapy for RA. SMIP(TM) drugs represent a novel class of immunotherapeutics that Trubion believes possess enhanced drug properties over monoclonal and recombinant antibodies.

In February 2006, the Company completed enrollment in a Phase IIa study in RA patients designed to demonstrate proof of concept that TRU-015 measurably improves the signs and symptoms of rheumatoid arthritis. In the first 24 weeks after receiving intravenous infusions of TRU-015, 72 percent of the subjects experienced a clinical response that is equal to or greater than that required to achieve an ACR20 response, 28 percent achieved an ACR50 response and 14 percent achieved an ACR70 response. In these measures of clinical response, ACR 50 and ACR70 indicate progressively greater responses from a baseline measure than ACR20, which is defined as an improvement of at least 20 percent from baseline in counts of both tender and swollen joints, as well as in at least three of five other disease activity parameters.

About Rheumatoid Arthritis

According to Datamonitor, RA is estimated to affect approximately 4.3 million people in the United States, Japan and Europe. In 2005, total reported worldwide sales of protein therapeutics used for the treatment of RA were $7.6 billion. Total worldwide sales of protein therapeutics for the treatment of RA are expected to grow to $10 billion in 2010.

About Trubion

Trubion is a biopharmaceutical company creating a pipeline of product candidates to treat autoimmune disease and cancer. The Company’s product candidates are novel proteins known as single-chain polypeptides and are designed using its SMIP(TM) custom drug assembly technology. In less than 24 months, the Company designed, developed and submitted to the FDA an Investigational New Drug application for its lead product candidate, TRU-015, which is currently being tested in a Phase IIb clinical trial for the treatment of rheumatoid arthritis. In December 2005, the Company entered into a collaboration agreement with Wyeth for the development and worldwide commercialization of certain therapeutics, including TRU-015. In addition, Trubion’s TRU-016 program targets CD37, an antigen present on B cells, for the treatment of non-Hodgkin’s lymphoma and chronic lymphocytic leukemia. Subject to satisfactory completion of preclinical testing of TRU-016, the Company expects to file an IND for TRU-016 in the second half of 2007. Trubion currently retains all development and commercialization rights for the TRU-016 program. For additional information visit www.trubion.com .

Forward Looking Statements

Certain statements in this release may constitute "forward-looking statements" within the meaning of Section 21E of the Securities Exchange Act of 1934 and Section 27A of the Securities Act of 1933. These statements include, but are not limited to, those related to the company’s future clinical development programs and the timing thereof, future clinical development plans, the details of the clinical trials and the results and timing thereof, the timing of regulatory applications and action. These statements are based on current expectations and assumptions regarding future events and the expected future size of the market for protein therapeutics for the treatment of RA, and business performance and involve certain risks and uncertainties that could cause actual results to differ materially. These risks include, but are not limited to, risks associated with the ability of the company to successfully conduct clinical trials for TRU-015 and other SMIP(TM) candidates, the uncertainty of the FDA approval process and other regulatory requirements, the therapeutic and commercial value of Trubion’s drug candidates, the company’s collaboration relationship with Wyeth, including its ability to receive milestone payments from Wyeth, and risks associated with defending and enforcing any patent claims and other intellectual property rights; and such other risks as identified in the company’s quarterly report on Form 10-Q for the period ended September 30, 2006 and from time to time in other reports filed by Trubion with the U.S. Securities Exchange Commission. These reports are available on the Investors page of the company’s corporate Web site at www.trubion.com. Trubion undertakes no duty to update any forward-looking statement to conform the statement to actual results or changes in the company’s expectations.

TRBN-G

Jim DeNike
Senior Director, Corporate Communications
Trubion Pharmaceuticals, Inc.
206-838-0500

SOURCE Trubion Pharmaceuticals, Inc.