ROCKVILLE, MD – August 23, 2005 – EntreMed, Inc. (Nasdaq: ENMD), a clinical-stage pharmaceutical company developing therapeutics primarily for the treatment of cancer and inflammatory diseases, today announced the presentation of positive preclinical results for its lead compound, 2-methoxyestradiol (2ME2), in models of rheumatoid arthritis. The data were presented during the 7th World Congress on Inflammation, being held August 20 – 24, 2005 in Melbourne, Australia.

Preclinical studies demonstrated that daily oral administration of 2ME2 resulted in a dose-dependent decrease in inflammation and tissue destruction in two distinct animal models of rheumatoid arthritis. Two parameters for assessing inflammatory responses, infiltration of inflammatory cells and pannus severity, showed a clear dose-dependent improvement with 2ME2-treatment. Cartilage lesion and bone resorption severity scores, two parameters that assess tissue destruction processes, also displayed a dose-dependent decline after treatment with 2ME2. Treatment with 100 mg/kg of 2ME2 was nearly 100% effective in the inhibition of inflammatory response and tissue destructive processes in a collagen-induced arthritis model. In addition, in an adjuvant-induced arthritis model, 2ME2 inhibited arthritis to a level comparable to standard of care agents, Enbrel® and methotrexate.

Carolyn F. Sidor, MD, MBA, EntreMed Vice President and Chief Medical Officer commented on the presentation, “We continue to generate positive preclinical data demonstrating the impact of 2ME2 on inflammation and disease progression in rheumatoid arthritis. These data, as well as data from previous preclinical studies, support 2ME2’s potential as a disease modifying anti-rheumatic drug (DMARD) candidate. While we continue evaluating 2ME2 (Panzem® Capsules and Panzem® NCD) in oncology, we will conduct further preclinical studies in rheumatoid arthritis to explore additional clinical opportunities for this compound. Our goal is to file an IND for 2ME2 in rheumatoid arthritis in 2006.”

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

About Rheumatoid Arthritis and Inflammation

Rheumatoid arthritis affects over 2 million American adults, of which about two-thirds of them are women. The disease, characterized by pain, stiffness, swelling, and deformity can become debilitating. Within 5 years of diagnosis, a third of patients are no longer working, and within 10 years, half of the patients have substantial functional disability. RA can shorten life expectancy by 5-10 years.

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. 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 and rheumatoid 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. Additional information about EntreMed is available on the Company’s website at www.entremed.com and in various filings with the Securities and Exchange Commission.

Forward Looking Statements
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