Langhorne, PA and Oxford, UK – 4 May 2011

Langhorne, PA and Oxford, UK – May 4, 2011 – EUSA Pharma, a transatlantic specialty pharmaceutical company focused on oncology, oncology supportive care and critical care, today announced that the US Food and Drug Administration (FDA) has determined that it requires an additional 90 days to complete its priority review of the Biologics License Application (BLA) for ERWINAZETM. As a result, the FDA has moved its decision date from May 3, 2011 to August 2, 2011.

Following EUSA’s submission of the ERWINAZE BLA, the FDA requested further information, which the company has provided. The Agency has classified this as a major amendment, requiring a 90 day extension for complete review.

EUSA Pharma remains positive about its ERWINAZE development program and its interactions with the FDA. The company is committed to continuing its collaboration with the Agency to complete the BLA review, and looks forward to providing this key treatment alternative for leukemia to help address an important unmet medical need.

ERWINAZE (L-asparaginase derived from Erwinia chrysanthemi) is currently approved for the treatment of acute lymphoblastic leukemia in patients with hypersensitivity to E. coli-derived asparaginase in a number of countries, including Canada, the UK and several European Union member states. The product is supplied in the United States under a treatment IND and has been awarded orphan drug designation by the FDA, providing a seven-year period of market exclusivity upon approval.