Nuvelo, Inc. (Nasdaq: NUVO) announced preclinical data demonstrating the mechanism of action and the potent therapeutic activity of NU206 (R-spondin1) in chemotherapy or radiation-induced oral mucositis models. The data were presented in a poster session yesterday at the 2008 American Association for Cancer Research (AACR) Annual Meeting in San Diego, CA.

The study, conducted in mouse models of oral mucositis, showed that NU206 regenerated basal layer epithelial cells and accelerated cell repair by stimulating the Wnt pathway, a signaling pathway that is critical for cell growth and differentiation during homeostasis and pathogenesis.

"This study reinforces our belief that NU206 is a potent regenerative agent," said Dr. Ted W. Love, chairman and chief executive officer of Nuvelo. "We are on track to begin a Phase 1 trial with NU206 in the second quarter of this year, and are also assessing the therapeutic potential of other secreted proteins in the R-spondin family through our Wnt therapeutics program, which targets a range of indications where cell regeneration and differentiation are important to disease processes, including gastrointestinal disease, bone disorders, wound healing and cancer."

About NU206 and R-Spondin secreted proteins

NU206 (R-spondin1) is a recombinant, secreted protein that acts as a highly specific regulator of the gastrointestinal epithelial cell function as demonstrated in early animal studies. Preclinical studies suggest it can promote growth and repair in animal models of radiation or cancer chemotherapy induced gastrointestinal injury, as well as in animal models of inflammatory bowel disease.

The R-spondin (Rspo) family of secreted proteins are the first biologic agents that can be used to enhance endogenous Wnt signaling in vivo, and provide therapeutic potential in diseases that are dependent on the Wnt pathway for maintenance of tissue integrity and tissue repair. Rspo proteins are novel regulators of the Wnt pathway and were first identified by Nuvelo as potent gastrointestinal mitogens in transgenic mice(1).

About Nuvelo

Nuvelo, Inc. is dedicated to improving the lives of patients through the discovery, development and commercialization of novel drugs for acute cardiovascular disease, cancer and other debilitating medical conditions. Nuvelo's development pipeline includes NU172, a direct thrombin inhibitor in Phase 1 development for use as a potential short-acting anticoagulant during medical or surgical procedures; and preclinical candidate NU206, a Wnt pathway modulator for the potential treatment of chemotherapy/radiation therapy-induced mucositis and inflammatory bowel disease. In addition, Nuvelo is pursuing research programs in leukemia and lymphoma therapeutic antibodies and Wnt signaling pathway therapeutics to further expand its pipeline and create additional partnering and licensing opportunities.

This press release contains "forward-looking statements," which include statements regarding the timing, progress and anticipated completion of Nuvelo's clinical stage and research programs, the anticipated availability of top-line data, projected operating expenses and cash usage and the potential benefits that patients may experience from the use of our clinical stage compounds, which statements are hereby identified as "forward-looking statements" for purposes of the safe harbor provided by the Private Securities Litigation Reform Act of 1995. Such statements are based on our management's current expectations and involve risks and uncertainties. Actual results and performance could differ materially from those projected in the forward- looking statements as a result of many factors, including, without limitation, uncertainties relating to drug discovery and the regulatory approval process; clinical development processes; enrollment rates for patients in our clinical trials; changes in relationships with strategic partners and dependence upon strategic partners for the performance of critical activities under collaborative agreements; and the impact of competitive products and technological changes. These and other factors are identified and described in more detail in Nuvelo's filings with the SEC, including without limitation Nuvelo's annual report on Form 10-K for the year ended December 31, 2007 and subsequent filings. We disclaim any intent or obligation to update these forward-looking statements.

(1) Kim et al. (2005) Mitogenic influence of human R-spondin1 on the intestinal epithelium. Science 309.

Nuvelo, Inc.
http://www.nuvelo.com