ROCKVILLE, MD, April 14, 2005—EntreMed, Inc. (Nasdaq: ENMD) today announced that the U.S. Food and Drug Administration (FDA) has granted orphan drug designation for the Company’s lead compound, 2- methoxyestradiol (2ME2 or Panzem®), for the treatment of ovarian cancer.

The FDA accepted EntreMed’s 2ME2 application upon review of data from preclinical experiments and a Phase I clinical study, together with in vitro data demonstrating that 2ME2 has activity against a variety of ovarian carcinoma cell lines including those resistant to other chemotherapeutic agents. In a Phase I study conducted by the National Cancer Institute with EntreMed’s initial formulation of 2ME2, Panzem® Capsules, an ovarian cancer patient experienced a durable partial response to 2ME2 after failing three prior chemotherapy regimens.

Carolyn F. Sidor, M.D., EntreMed Vice President and Chief Medical Officer commented on the designation, “Ovarian cancer accounts for 4% of the total cancers in women in the United States. 2ME2 inhibits the proliferation of ovarian carcinoma cell lines in vitro, has antiangiogenic properties, and it binds to tubulin, properties that are important in the treatment of ovarian cancer. We look forward to initiating additional clinical studies to further evaluate 2ME2 alone and in combination with other chemotherapeutic agents in this patient population.”

Orphan drug is a designation by the Food and Drug Administration indicating a therapy developed to treat diseases that affect fewer than 200,000 persons in the United States. Sponsors of drugs granted orphan designation qualify for tax credit and marketing exclusivity incentives of the Orphan Drug Act. EntreMed received orphan drug designation previously for 2ME2 in the treatment of multiple myeloma, a type of blood cancer. A 60-patient, Phase II Panzem® Capsule study in multiple myeloma, conducted at the Mayo Clinic and the Dana Farber Cancer Institute, has now completed enrollment. Additional clinical studies in multiple myeloma are planned.

About Ovarian Cancer

Ovarian cancer accounts for 4% of all cancers among women in the U.S., and ranks fifth as the cause of cancer deaths. About half of all ovarian cancers occur in post-menopausal women. Ovarian cancer is often asymptomatic in the early stages. As a result, ovarian cancer is often not diagnosed until stage III or IV, where 5-year survival rates decline to 15-20%. Current drug therapy involves paclitaxel and carboplatin/cisplatin regimens. Many patients develop resistance to these drugs, so there is substantial need for innovative therapies that can overcome resistance, either as a single agent or in combination with cytotoxic agents.

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 http://www.entremed.com and in various filings with the Securities and Exchange Commission.

Forward Looking Statements

This release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act with respect to the outlook for expectations for future financial or business performance, strategies, expectations and goals. Forward-looking statements are subject to numerous assumptions, risks and uncertainties, which change over time. Forward-looking statements speak only as of the date they are made, and no duty to update forward-looking statements is assumed. Actual results could differ materially from those currently anticipated due to a number of factors, including those set forth in Securities and Exchange Commission filings under “Risk Factors,” including risks relating to the need for additional capital and the uncertainty of additional funding; the early-stage products under development; uncertainties relating to clinical trials; success in the clinical development of any products; dependence on third parties; future capital needs; and risks relating to the commercialization, if any, of the Company’s proposed products (such as marketing, safety, regulatory, patent, product liability, supply, competition and other risks).