Hana Biosciences Receives Orphan Drug Designation for Talotrexin (PT-523), For the Treatment of Acute Lymphoblastic Leukemia.

SOUTH SAN FRANCISCO, Calif. -- Hana Biosciences (NASDAQ:HNAB), a biopharmaceutical company focused on advancing cancer care, announced that the U.S. Food and Drug Administration has granted orphan drug designation for Talotrexin (PT-523) in patients with acute lymphoblastic leukemia (ALL). Talotrexin, a novel nonpolyglutamatable antifolate drug, is currently being evaluated in a Phase I/II multicenter clinical trial in patients with relapsed or refractory ALL.

"This designation underscores the need for improved therapies in ALL, and supports our development strategy in areas of unmet need. Hana Biosciences is committed to accelerating the clinical development of Talotrexin in this disease," commented Greg Berk, MD, Senior Vice President and Chief Medical Officer of Hana Biosciences.

About Orphan Drug Designation

The Orphan Drugs Act provides for economic incentives to encourage the development of drugs for diseases affecting fewer than 200,000 people in the United States. Orphan drug designation entitles Hana Biosciences to seven years of market exclusivity for Talotrexin in the treatment of ALL. Additional incentives include tax credits related to clinical trial expenses, a possible exemption from the FDA-user fee, and assistance in clinical trial protocol design.

About Talotrexin

Talotrexin, which Hana licensed from Dana-Farber Cancer Institute, Inc. (DFCI) and Ash Stevens, Inc. in December 2002, is a novel antifolate drug candidate under development for treatment of various types of tumors. Antifolates, also known as folic acid analogs, are a class of cytotoxic or antineoplastic agents which inhibit or prevent the maturation and proliferation of malignant cells. Antifolates have been used for more than 30 years to treat both solid and hematological cancers such as breast cancer and ALL, as well as inflammatory diseases such as rheumatoid arthritis. Talotrexin has demonstrated enhanced antitumor activity in a broad spectrum of cancer models by targeting the enzyme DHFR to prevent DNA synthesis in tumor cells and inhibit tumor growth. Preclinical studies performed by the DFCI and the National Cancer Institute suggest that Talotrexin, as compared to methotrexate, the most widely used antifolate, enters into cells up to 10 times more efficiently and demonstrates 10- to 100-fold more potency in overcoming polyglutamation, a well-established mechanism of antifolate resistance. Talotrexin also binds more tightly to its anti-tumor target DHFR, which Hana believes may further inhibit tumor growth. Hana commenced a Phase I clinical trial in solid tumors in February 2005, a Phase I/II clinical trial in NSCLC in March 2004, and a Phase I/II clinical trial in ALL in May 2005.Additional information regarding these ongoing trials can be accessed at www.hanabiosciences.com.

About Acute Lymphoblastic Leukemia (ALL)

ALL is a type of blood and bone marrow cancer -- the spongy tissue inside bones where blood cells are made. Acute leukemias progress rapidly and affect immature blood cells, rather than mature ones. Acute lymphoblastic leukemia affects a group of white blood cells called lymphocytes, which fight infection. Normally, bone marrow produces immature cells (stem cells) in a controlled way, and they mature and specialize into the various types of blood cells, as needed. In people with ALL, this production process goes awry. Large numbers of immature, abnormal lymphocytes called lymphoblasts are produced and released into the bloodstream. These abnormal cells are not able to mature and perform their usual functions. Furthermore, they multiply rapidly and can crowd out healthy blood cells, leaving an adult or child with ALL vulnerable to infection or easy bleeding. Leukemic cells can also collect in certain areas of the body, including the central nervous system and spinal cord, which can cause serious problems. Almost 4,000 Americans are diagnosed with ALL each year. This form of cancer worsens quickly if not treated, but it usually responds well to initial treatment. Adults have a 20% to 40% cure rate, underscoring the need for new therapeutic options.

About Hana Biosciences, Inc.

Hana Biosciences, Inc. (NASDAQ:HNAB) is a South San Francisco, CA-based biopharmaceutical company that acquires, develops, and commercializes innovative products to advance cancer care. The company is committed to creating value by building a world-class team, accelerating the development of lead product candidates, expanding its pipeline by being the alliance partner of choice, and nurturing a unique company culture. Additional information on Hana Biosciences can be found at www.hanabiosciences.com.

This press release contains forward-looking statements within the meaning of the Private Securities Litigation Reform Act of 1995. Such statements involve risks and uncertainties that could cause Hana's actual results to differ materially from the anticipated results and expectations expressed in these forward-looking statements. These statements are often, but not always, made through the use of words or phrases such as "anticipates," "expects," "plans," "believes," "intends," and similar words or phrases. These statements are based on current expectations, forecasts and assumptions that are subject to risks and uncertainties, which could cause actual outcomes and results to differ materially from these statements. Among other things, there can be no assurances that any of Hana's development efforts relating to its product candidates, including those recently licensed from INEX, will be successful. Other risks that may affect forward-looking information contained in this press release include the possibility of being unable to obtain regulatory approval of Hana's product candidates, the risk that the results of clinical trials may not support Hana's claims, Hana's reliance on third-party researchers to develop its product candidates, and its lack of experience in developing and commercializing pharmaceutical products. Additional risks are described in the company's Quarterly Report on Form 10-Q for the three months ended March 31, 2006 filed with the Securities and Exchange Commission. Hana assumes no obligation to update these statements, except as required by law.