Bioenvision's Clofarabine Granted 'orphan drug' Status for AML in Europe.

Business Editors/Health/Medical Writers

NEW YORK--(BUSINESS WIRE)--April 2, 2003

Bioenvision, Inc. (OTCBB: BIOV) today announced that following the favorable opinion of the European Agency for the Evaluation of Medicinal Products (EMEA - adopted by the committee of Orphan Medical Products), the European Commission has granted an 'Orphan Medicinal Product' designation for the anticancer drug Clofarabine as a treatment for Acute Myeloblastic Leukemia (AML).

The EMEA's "orphan drug" designation promotes the development of drugs to treat rare diseases or conditions. Obtaining this designation provides marketing exclusivity for 10 years, during which the drug development process is enhanced by EMEA's providing protocol assistance and access to the Centralized Procedure for the application for marketing approval. Further, drugs that receive "orphan drug" designation get the benefit of reduced application fees for marketing approvals and protocol assistance and, potentially, a European Union research funding grant.

"EMEA orphan drug designation for Clofarabine in AML should accelerate the approval process in Europe by allowing us to pursue our preferred development path in AML. With the encouraging results of Clofarabine in refractory adult AML, we will now commence Phase II trials of the drug as a first line therapy in elderly patients with AML," said Dr. Christopher B. Wood, Chairman and Chief Executive Officer of Bioenvision.

"We are gratified to have received rapid approval for this designation, which complements the orphan drug designation that Clofarabine received in the U.S. and Europe for Acute Lymphocytic Leukemia in 2002," added Dr. Wood. "In addition, with a decade of market exclusivity in Europe, the orphan drug designation protects our intellectual property position on Clofarabine for the next ten years."

About AML

Acute myelogenous leukemia (AML) is an overproduction of immature myeloid white blood cells due to a defect in the DNA of these cells in the bone marrow. Not being able to mature, these cells proliferate in number interfering with the body's ability to fight infection and prevent bleeding. AML is the most common type of acute leukemia in adults, affecting adults of all ages, but more common in older age groups (average age at diagnosis = 65 years) and more common in men than women.

About Clofarabine

Clofarabine (Cl-F-ara-A, CAFdA) is a second generation purine nucleoside antimetabolite. Nucleoside analogs are antimetabolites that affect DNA synthesis. Clofarabine combines many of the favorable properties of the two most commonly used nucleoside analogs, Fludarabine Fludara(R) by Schering AG (NYSE: SHR) and Cladribine, Leustatin(R) by Johnson and Johnson (NYSE: JNJ), but is reported to have greater potency at damaging the DNA of Leukemia cells than these other agents. (Blood, "Mitochondrial Toxity of Deoxyadenoside Analogs", November 15, 2000, Volume 96, Number 10). In a single centre Phase II study of Clofarabine in patients with refractory AML, 42% of the patients had a complete response rate (CR) and a further 13% had a partial response (CRp).

About Bioenvision

Bioenvision's (OTCBB: BIOV.OB - News) 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; Modrenal(R) (for which Bioenvision has obtained regulatory approval for marketing in the United Kingdom for the treatment of post-menopausal breast cancer); and other products in clinical trials. Bioenvision is also developing anti-infective technologies, including the OLIGON technology, an advanced biomaterial that has been approved for certain indications by the FDA in the U.S.

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.