EntreMed Presents MKC-1 Phase 2 Data at American Society of Clinical Oncology Annual Meeting

Antitumor Activity Demonstrated in Metastatic Breast Cancer Patients

ROCKVILLE, Md., June 3—EntreMed, Inc. (Nasdaq: ENMD), a clinical-stage pharmaceutical company developing therapeutics for the treatment of cancer and inflammatory diseases, today announced the presentation of clinical data for the MKC-1 Phase 2 study in patients with metastatic breast cancer. The data were presented by Bryan P. Schneider, M.D., Assistant Professor, Department of Medicine, Indiana University, during the Breast Cancer—Metastatic session at the American Society of Clinical Oncology Annual Meeting being held this week in Chicago, Illinois.

For this Phase 2 single agent, open label study, a total of 65 patients who had previously received at least one anthracycline and taxane therapy were enrolled. 55 patients were evaluable for tumor response. Of the evaluable patients, the antitumor activity observed with MKC-1 included 3 patients who had responses and 5 patients with stable disease lasting more than four months.

MKC-1 is a novel, orally-active cell cycle inhibitor with in vitro and in vivo efficacy against a broad range of human solid tumor cell lines, including multi-drug resistant cell lines. Data from previous studies with MKC-1 demonstrate broad-acting antitumor effects, showing tumor growth inhibition or regression in multiple preclinical models, including paclitaxel-resistant models. To date, MKC-1 has been evaluated in over 400 patients in multiple Phase 1 and 2 clinical trials.

Carolyn F. Sidor, MD, MBA, EntreMed Vice President and Chief Medical Officer commented on the results, “Although we did not meet our overall goal for this study, we are encouraged by the number of patients who did respond or have stable disease in this heavily pre-treated patient population. Going forward, further work may enable us to define why some breast cancer patients responded to MKC-1 treatment. Combining information from these studies with new mechanistic insights that have revealed mTOR and HIF-1alpha as molecular targets of MKC-1, we will be in a better position to design future clinical studies in defined, less refractory patient subsets that will benefit from MKC-1 treatment. Additionally, based on data from several preclinical models, we believe that by administering MKC-1 on a continuous dosing schedule, we should be able to enhance the compound’s antitumor activity. Additional clinical studies utilizing continuous dosing are already underway.”

“EntreMed has made significant progress towards an understanding of MKC-1 mechanism since the initiation of this Phase 2 study,” commented EntreMed Vice President of Research, Mark R. Bray, PhD. Dr. Bray continued, “Refinements to dose and schedule, and translational studies based on MKC-1’s newly-discovered activity towards the mTOR/PI3-kinase pathway have been incorporated into ongoing and planned MKC-1 trials. Additionally, we are exploring the molecular basis for resistance and sensitivity of cancer cells to MKC-1 both internally and through collaborations. We feel that the information derived from these mechanistic and clinical studies will assist in defining how best to utilize MKC-1, which has demonstrated activity in drug resistant patient populations.”

To view a copy of the poster presentation, visit the Therapeutic Pathways section of the Company’s website at www.entremed.com .

About EntreMed
EntreMed, Inc. is a clinical-stage pharmaceutical company developing therapeutic candidates primarily for the treatment of cancer and inflammation. MKC-1 is currently in multiple Phase 2 clinical trials for cancer. MKC-1 is an oral cell-cycle regulator with activity against the mTOR pathway. ENMD-1198, a novel antimitotic agent, and ENMD-2076, a selective kinase inhibitor, are in Phase 1 studies in advanced cancers. The Company also has an approved IND application for Panzem(R) in rheumatoid arthritis. 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 web site at 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 (including the timing of royalty revenues and future R&D expenditures), 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; variations in actual sales of Thalomid(R), risks associated with the Company’s product candidates; the early-stage products under development; results in preclinical models are not necessarily indicative of clinical results, uncertainties relating to preclinical and 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).