Clofarabine Active in a Broad Range of Hematologic Cancers; Data Presented at 10th European Haematology Association -EHA- Symposium.

STOCKHOLM, Sweden -- Bioenvision (Nasdaq: BIVN) announced that clofarabine's potential as the next generation of leukemia treatment was a focal point during a symposium led by internationally renowned haematologists from the MD Anderson Cancer Center, Houston, Texas, at the 10th European Haematology Association (EHA) meeting in Stockholm, Sweden.

A main focus of attention at the symposium was clofarabine's activity in leukaemia. Clofarabine has recently been approved by the FDA for the treatment of relapsed/refractory acute lymphoblastic leukaemia in pediatric patients. However, Dr. Stefan Faderl, presented data at the meeting in which clofarabine was used as first-line treatment of acute myeloid leukaemia (AML) in adults. This Phase II, investigator-sponsored study was conducted at MDACC and was presented for the first time in Europe. This study compared clofarabine as a single agent versus clofarabine in combination with low-dose ara-C in patients greater than or equal to 60 years (median age 72 years) and showed that clofarabine as a single agent achieved a CR of 45% (5/11) and clofarabine in combination with low-dose ara-C achieved a CR of 60% (12/20).

Professor Hagop Kantarjian reviewed data from a small investigator-sponsored study of clofarabine in high-risk myelodysplastic syndrome (MDS), in which a complete response rate (CR + CRp) of 50% was observed, and stated that clofarabine was one of the new agents that offered hope for the future in MDS.

Dr. William Plunkett referred to the ongoing investigator-sponsored Phase I clinical study of clofarabine in chronic lymphocytic leukaemia (CLL). He also presented data on the accumulation and retention of clofarabine in lymphocytes from patients with CLL and showed clofarabine to be far more active than fludarabine or ara-C. In addition, Dr. Plunkett presented experimental evidence for the synergistic effect of combining clofarabine with a range of DNA-damaging agents and showed the potential for clofarabine in combination regimens for the treatment of both hematologic cancers and solid tumors.

Each of the investigator-sponsored studies referred to by Drs. Faderl, Kantarjian and Plunkett have been conducted with the support of our co-development partner, Genzyme Corporation (Nasdaq: GENZ).

"We are encouraged to see clofarabine being studied in a broad range of hematologic cancers thereby enabling us to further build upon clofarabine's commercial potential" said Dr Chris Wood, CEO and Chairman of Bioenvision.

About Clofarabine

Clofarabine is a next generation of the drug class, purine nucleoside analogs that inhibit DNA production necessary for cancer cell growth. Bioenvision and Genzyme are co-developing clofarabine. Bioenvision holds an exclusive worldwide license to clofarabine (outside Japan and Southeast Asia). Bioenvision granted an exclusive sublicense to Genzyme to develop and commercialize clofarabine for cancer indications in the United States and Canada. Bioenvision holds an exclusive license in the US and Canada to all non-cancer indications and an exclusive, irrevocable option to develop and market clofarabine for all human applications in Japan and Southeast Asia.

Bioenvision originally obtained clofarabine development and commercialization rights under patents held by Southern Research Institute.

Clofarabine has been granted orphan drug designation for the treatment of adult and pediatric ALL and AML in the U.S. and Europe. In the U.S., orphan drug status extends market exclusivity for seven years. The FDA also recently granted an additional six months market exclusivity to clofarabine under the Best Pharmaceuticals for Children Act. In Europe, the designation provides marketing exclusivity for 10 years.

About Bioenvision

Bioenvision's primary focus is the acquisition, development and distribution of compounds and technologies for the treatment of cancer. Bioenvision has a broad pipeline of products for the treatment of cancer, including: Clofarabine (in co-development with Genzyme Corporation), Modrenal(R) (for which Bioenvision has obtained regulatory approval for marketing in the United Kingdom for the treatment of post-menopausal breast cancer following relapse to initial hormone therapy), and other products in clinical trials. Bioenvision is also developing anti-infective technologies, including the OLIGON technology; an advanced biomaterial that has been incorporated into various FDA approved medical devices. For more information on Bioenvision please visit our Web site at www.bioenvision.com.

Certain statements contained herein are "forward-looking" statements (as such term is defined in the Private Securities Litigation Reform Act of 1995). Because these statements include risks and uncertainties, actual results may differ materially from those expressed or implied by such forward-looking statements. Specifically, factors that could cause actual results to differ materially from those expressed or implied by such forward-looking statements include, but are not limited to: risks associated with preclinical and clinical developments in the biopharmaceutical industry in general and in Bioenvision's compounds under development in particular; the potential failure of Bioenvision's compounds under development to prove safe and effective for treatment of disease; uncertainties inherent in the early stage of Bioenvision's compounds under development; failure to successfully implement or complete clinical trials; failure to receive marketing clearance from regulatory agencies for our compounds under development; acquisitions, divestitures, mergers, licenses or strategic initiatives that change Bioenvision's business, structure or projections; the development of competing products; uncertainties related to Bioenvision's dependence on third parties and partners; and those risks described in Bioenvision's filings with the SEC. Bioenvision disclaims any obligation to update these forward-looking statements.