Bioenvision and Mayne Pharma Announce Marketing and Distribution Agreement for Evoltra(R); Exporting Evoltra(R) Rights Commences in Australia and New Zealand.

NEW YORK -- Bioenvision, Inc (NASDAQ: BIVN) and Mayne Pharma Limited (ASX- MYP) today jointly announced that they have entered into a Marketing and Distribution Agreement for the innovative new cancer product, Evoltra(R) (clofarabine).

Under the agreement, Bioenvision granted Mayne Pharma exclusive rights to market Evoltra(R) (clofarabine) for certain haematological malignancies in Australia and New Zealand. Bioenvision will receive milestone payments and a percentage of Mayne's net sales revenue. Mayne Pharma is responsible for securing regulatory approval and government reimbursement in Australia and New Zealand.

Michael Kotsanis, President of the Asia Pacific region for Mayne Pharma said: "Evoltra(R) is an exciting addition to our growing branded oncology portfolio. We are very pleased to enter into a partnership with Bioenvision to bring an important new oncology product into the Australian and New Zealand market. We look forward to filing the regulatory dossier with the Australian and New Zealand agencies in the second half of 2006."

Clofarabine has been approved in the United States for the treatment of acute lymphoblastic leukaemia in paediatric patients who have relapsed or are refractory to other chemotherapies. In Europe, the CHMP have adopted a positive opinion for the use of Evoltra(R) (clofarabine) in "the treatment of acute lymphoblastic leukemia (ALL) in pediatric patients who have relapsed or are refractory to at least two prior regimens and where there is no other treatment option anticipated to result in a durable response. Safety and efficacy have been assessed in studies of patients less than or equal to 21 years old at initial diagnosis."

Bioenvision is also developing Evoltra(R) for the treatment of other haematological malignancies including for use as first line therapy of adult acute myeloid leukaemia (AML).

Dr. John Seymour MBBS FRACP, Chairman of the Australasian Leukaemia and Lymphoma Clinical Trials Group said: "The clinical data presented at recent international conferences on the use of Evoltra(R) in elderly patients with AML appear very promising, with encouraging efficacy and good tolerability. Effective new agents for use in the first line setting for these patients would be of great interest to Australian haematologists, as this is an area of clear un-met need." Note: Dr. Seymour has acted as a consultant for Mayne Pharma.

Dr. Christopher B. Wood, Chairman and Chief Executive Officer of Bioenvision added "we are delighted to be working with Mayne Pharma given its marketing and distribution capabilities in these territories and to get this very active cancer agent into the Australian and New Zealand markets. This is the first step of the build out of the Evoltra(R) franchise beyond Europe and the U.S. and demonstrates our overarching strategy to expand the geographical reach of this exciting cancer agent."

About Evoltra(R) (clofarabine):

The CHMP have adopted a positive opinion for the use of Evoltra(R) (clofarabine) in "the treatment of acute lymphoblastic leukemia (ALL) in pediatric patients who have relapsed or are refractory to at least two prior regimens and where there is no other treatment option anticipated to result in a durable response. Safety and efficacy have been assessed in studies of patients less than or equal to 21 years old at initial diagnosis."

Bioenvision is also developing Evoltra(R) for the treatment of adult acute myeloid leukemia (AML) as first-line therapy. The Company has completed enrollment of its Phase II clinical trial for the treatment of adult AML in elderly patients unfit for intensive chemotherapy and expects to file a Marketing Authorization Application in mid-2006 for the Company's first label-extension for Evoltra(R) .

In addition, clofarabine is in clinical development for the treatment of myelodysplastic syndrome (MDS), chronic lymphocytic leukemia (CLL), chronic myeloid leukemia (CML), non-Hodgkin's lymphoma (NHL), multiple myeloma (MM), solid tumors and as a preconditioning regimen for transplantation. Bioenvision is also conducting late-stage preclinical development of Evoltra(R) for the treatment of psoriasis and is planning further worldwide development of Evoltra(R) in autoimmune diseases.

Evoltra(R) (clofarabine) is a next generation purine nucleoside analog. Bioenvision holds an exclusive worldwide license for clofarabine (outside Japan and Southeast Asia) and an exclusive, irrevocable option to develop and market clofarabine for all human applications in Japan and Southeast Asia. Bioenvision granted an exclusive sublicense to Genzyme to co-develop clofarabine for cancer indications in the US and Canada. Genzyme is commercializing clofarabine for cancer indications in the US and Canada under the brand name Clolar(R). Bioenvision holds an exclusive license in the US and Canada for all non-cancer indications. 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 both ALL and AML in the U.S. and Europe. In Europe, the designation provides marketing exclusivity for 10 years following Marketing Authorization.

About Mayne Pharma:

Mayne Pharma Limited focuses on the development, manufacture, sale and distribution of medicines used by oncologists. The company is listed on the Australian Stock Exchange under the code "MYP".

Mayne Pharma's product portfolio has been built on world class process development capabilities in the two families of drugs that are commonly used in the treatment of cancer today: taxanes and platinum derivatives. The company has also expanded from its origins in generic chemotherapy medicines to related therapeutic drugs used by oncologists in the treatment of cancer such as antibiotics and pain management. On the back of this expertise, Mayne Pharma has expanded from Australia so that it now distributes its products in more than 65 countries around the world. It has established strong commercial footholds especially in Europe and Asia Pacific.

Mayne Pharma has increased its sales revenues significantly in the last three years on the back of acquisitions and internal growth. Pro-forma sales in its 2005 financial year were AU$687 million up approximately 35% on the prior year.

In November 2005, Mayne Pharma was demerged from Mayne Group Limited so the business could focus on its core competencies and have increased flexibility to implement appropriate strategies and a capital structure that would help facilitate its continued success. For more information on Mayne Pharma please visit our website at www.maynepharma.com/global/

About Bioenvision:

Bioenvision's primary focus is the acquisition, development, distribution and marketing of compounds and technologies for the treatment of cancer. Bioenvision has a broad pipeline of products for the treatment of cancer, including: Evoltra(R) (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. Bioenvision is also developing anti-infective technologies, including the OLIGON(R) 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 or Mayne Pharma's business, structure or projections; the development of competing products; uncertainties related to Bioenvision's and Mayne Pharma's dependence on third parties and partners; and those risks described in Bioenvision's filings with the SEC, and Mayne Pharma's filings with the ASX. Bioenvision and Mayne Pharma independently disclaim any obligation to update these forward-looking statements.