GlycoGenesys Initiates Additional Prestigious Medical Site for GCS-100 Phase I/II Multiple Myeloma Clinical Trial; Patient Screening Begins at Roswell Park Cancer Institute.

BOSTON -- GlycoGenesys, Inc. (NASDAQ:GLGS), a biotechnology company, today announced it has initiated Roswell Park Cancer Institute, (RPCI) Buffalo, New York as a clinical site for its Phase I/II dose escalation trial in patients with multiple myeloma, the second most common blood cancer. The trial is designed to evaluate the safety and efficacy of the Company's drug candidate, GCS-100. RPCI was the first cancer research center in the nation and is a National Cancer Institute designated comprehensive cancer center. The Principal Investigator at this site is Asher A. Chanan-Khan, M.D. Dr. Chanan-Khan is an Attending Physician, Division of Lymphoma/Myeloma, RPCI and an Assistant Professor of Medicine, RPCI and School of Biomedical Sciences, State University of New York, Buffalo. Dr. Chanan-Khan's research interests include novel therapies for multiple myeloma and chronic lymphocytic leukemia (CLL).

Dr. Chanan-Khan has participated in several important clinical studies in multiple myeloma, including the trials that led to regulatory approval of Velcade(R) marketed by Millennium Pharmaceuticals and Johnson and Johnson, as well as studies evaluating Celgene's Revlimid (R) in patients with CLL.

"I'm excited to be involved as a Principal Investigator in this trial. The preclinical evidence showing GCS-100's anti-cancer activity in multiple myeloma and CLL cell lines is compelling and suggests GCS-100 may provide therapeutic benefit in patients with these types of malignancies," stated Dr. Chanan-Khan.

About The Clinical Trial

The primary objective of the Phase I/II dose escalation study is to evaluate the safety of GCS-100 when given to patients with relapsed or refractory multiple myeloma and to identify the recommended dose for future studies. Secondary objectives are to evaluate the response to GCS-100 as a monotherapy and in combination with dexamethasone and determine the pharmacokinetics of GCS-100 alone and with dexamethasone.

The trial was designed with the assistance of Dr. Paul Richardson and Dr. Kenneth Anderson at the Dana-Farber Cancer Institute, Boston, MA based upon pre-clinical work conducted in Dr. Anderson's laboratory and recently published in Cancer Research 2005; 65:(18). This research shows that GCS-100:

--Induces cell death in multiple myeloma cells without significant toxicity against normal white blood cells;

--Directly targets multiple myeloma cells while in the presence of protective bone marrow cells;

--Triggers cell death in multiple myeloma cells resistant to commonly used anti-cancer agents including dexamethasone, melphalan, doxorubicin, and Velcade(R); and

--Has additive and/or synergistic effect when combined with caspase-activating agents such as dexamethasone.

About Multiple Myeloma

Multiple myeloma is a bone marrow cancer in which plasma cells, white blood cells that are normally responsible for the production of infection-fighting antibodies, become abnormal and are overproduced. The proliferation of these abnormal plasma cells, called myeloma cells, results in decreased production of normal blood cells and disease-fighting antibodies. This proliferation causes growth of tumors that spread to multiple sites - hence the term multiple myeloma. The decreased white blood cell production weakens the immune system and the decreased red blood cell production leads to fatigue and weakness, while the myeloma tumors cause bone destruction, pain and fractures.

Multiple myeloma is the second most common hematologic malignancy and although the disease is predominantly a cancer among older individuals (the average age of onset is 65 to 70 years of age), recent statistics indicate both increasing incidence and onset at a younger age. In the United States, more than 50,000 individuals have multiple myeloma and over 14,600 new cases of the disease are diagnosed each year. Worldwide, there are approximately 74,000 new cases and over 45,000 deaths due to multiple myeloma each year.

About GlycoGenesys, Inc.

GlycoGenesys, Inc. is a biotechnology company focused on carbohydrate drug development. The Company's drug candidate GCS-100, a unique compound to treat cancer, has been evaluated in previous clinical trials at low dose levels in patients with colorectal, pancreatic and other solid tumors with stable disease and partial response documented. The Company currently is completing a Phase I dose escalation trial to evaluate higher dose levels of GCS-100LE, a low ethanol formulation of GCS-100, at Sharp Memorial Hospital, Clinical Oncology Research in San Diego, California and the Arizona Cancer Center in both Tucson and Scottsdale, Arizona. In addition, GCS-100LE is being evaluated in a Phase I/II trial for multiple myeloma at the Dana-Farber Cancer Institute in Boston, Massachusetts. Further clinical trials are planned for 2005 and 2006. Further information is available on GlycoGenesys' web site: www.glycogenesys.com.

Safe Harbor Statement

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