ROCKVILLE, MD, April 5—EntreMed, Inc. (Nasdaq: ENMD) today announced the presentation of preclinical data for 2- methoxyestradiol (2ME2) in rheumatoid arthritis. The data were presented at the XXXV International Congress of Physiological Sciences during the annual meeting of the American Association of Immunologists being held this week in San Diego, California.

The anti-arthritic activity of 2ME2 was evaluated in a preclinical animal model of rheumatoid arthritis. Data from the study demonstrated that oral treatment with 2ME2 resulted in a dose-dependent decrease in severity of arthritic disease as determined by standard clinical measurements. A decrease in clinical symptoms with 2ME2 administration was accompanied by a marked inhibition of tissue and joint damage that are hallmarks of rheumatoid arthritis, such as inflammatory cell infiltrates, articular (joint) cartilage erosion, pannus (vascular connective tissue) formation, and bone resorption.

These data demonstrate that in this animal model of rheumatoid arthritis, 2ME2 decreases inflammation, halts disease progression, and indicates that 2ME2 has disease modifying antirheumatic drug (DMARD) properties.

Carolyn F. Sidor, MD, EntreMed Vice President and Chief Medical Officer, commented on the study, “It is now accepted that angiogenesis is a main contributor in the development and promotion of rheumatoid arthritis. Therefore, a potential way to attenuate the development of this disease is to disrupt the blood supply. The data being presented demonstrate that 2ME2, a known antiangiogenic agent, has the potential to be a disease modifying antirheumatic drug candidate. EntreMed is currently evaluating 2ME2 formulations (Panzem® Capsules and Panzem® NCD) in Phase I and II clinical oncology studies, as well as preclinical studies of 2ME2 in inflammatory diseases such as RA.”

To view the poster presentation, visit Scientific Presentations under the Therapeutic Pathways section of the Company’s website at http://www.entremed.com.

About Rheumatoid Arthritis and Inflammation

Rheumatoid arthritis (RA), one of the most common forms of arthritis, is a systemic disease that is characterized by the inflammation of the membrane lining of the joint, which causes pain, stiffness, redness, swelling, and loss of function in the joint. The inflamed joint lining, called the synovium, releases enzymes that destroy bone and cartilage, causing the joint to lose its shape and alignment. This process can result in joint pain, loss of movement, and deformity. RA may also cause inflammation of internal organs, leading to organ damage. DMARDs are drugs that have the ability to slow down disease progression in rheumatoid arthritis and other autoimmune diseases.

Inflammation is the process involving the reaction of tissue to injury or disease. The condition may be either local or systemic and can be divided into acute (immediate) and chronic (prolonged) patterns. The endothelial cell responses involved in angiogenesis (formation of new blood vessels) and homeostasis are central to inflammatory diseases. In contrast to acute inflammation, which is manifested by vascular changes, edema, and largely neutrophil infiltration, chronic inflammation is characterized by infiltration with mononuclear leukocytes, tissue destruction, angiogenesis, and fibrosis. As a result, the cellular pathways involved in acute and chronic inflammation can be overlapping or distinct. Inflammation is a process that is associated with many pathologies, including cancer, cardiovascular disease and arthritis. A number of EntreMed’s compounds have demonstrated anti-inflammatory properties in preclinical models.

About EntreMed

EntreMed, Inc. (Nasdaq: ENMD) is a clinical-stage pharmaceutical company developing therapeutic candidates primarily for the treatment of cancer and inflammation. Panzem® (2-methoxyestradiol or 2ME2), the Company’s lead drug candidate, is currently in clinical trials for cancer, as well as in preclinical development for non-oncology indications. EntreMed’s goal is to develop and commercialize new compounds based on the Company’s expertise in angiogenesis, cell cycle regulation and inflammation—processes vital to the treatment of cancer and other diseases, such as rheumatoid arthritis. Additional information about EntreMed is available on the Company’s website at http://www.entremed.com and in various filings with the Securities and Exchange Commission.

Forward Looking Statements

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