Chroma Therapeutics enters collaboration with Cell Therapeutics Inc

Oxford, UK and Seattle, US – Chroma Therapeutics Ltd and Cell Therapeutics, Inc. (“CTI”) (NASDAQ and MTA: CTIC) announced that the companies have entered into a co-development and license agreement providing CTI with exclusive marketing and co-development rights to Chroma’s drug candidate tosedostat in North, Central and South America. Tosedostat is an oral aminopeptidase inhibitor that has demonstrated significant anti-tumor responses in blood related cancers and solid tumors in Phase I-II clinical trials. The Companies expect to commence a Phase III clinical study in the United States and Europe in elderly patients with relapsed or refractory acute myeloid leukemia (“AML”) for potential approval by the U.S. Food and Drug Administration (“FDA”)and the European Medicines Agency (“EMA”). The FDA and the EMA have granted tosedostat orphan drug status for AML.

“Tosedostat, similar to drugs like bortezomib and lenalidomide, represents a departure from conventional cytotoxic chemotherapy toward more tumour selective targeted therapy that interferes with cellular pathways necessary for tumor survival,”

commented James A. Bianco, M.D., CEO of CTI.

“In clinical studies tosedostat was well tolerated, given orally once a day and produced encouraging response rates in difficult to treat patients with acute leukaemia and a variety of blood related cancers. We are excited to add tosedostat to our late stage product pipeline alongside pixantrone as we continue with our strategy of building a pipeline of novel drugs for treating blood-related cancers.”

Pursuant to the terms of the agreement, CTI will make an upfront payment to Chroma of $5 million and a milestone payment of $5 million when the AML pivotal trial is initiated, which is expected to occur in the fourth quarter of 2011. The agreement also includes customary development-based milestone payments related to AML, myelodysplastic syndrome (“MDS”) and certain other indications, as well as royalties on net sales in CTI’s territories. CTI will oversee development operations and commercialisation activities in its territories and Chroma will oversee development operations and commercialization activities in the rest of the world. Subject to a funding cap of $50 million for the first three years, CTI will be responsible for 75% of development costs and Chroma will be responsible for 25% of development costs.

“We believe that this is a collaboration that should enable the rapid progression of tosedostat towards seeking regulatory approval, given CTI’sdevelopment and commercialisation capabilities and experience in the blood-related cancer space.,”

said Ian Nicholson, CEO of Chroma.

“In working with clinicians in developing tosedostat we have clearly identified significant unmet needs where tosedostat could provide an important therapeutic advance for patients if approved.”

About AML

AML is a haematologic cancer that is an aggressive, fast-growing cancer that starts inside the bone marrow with the production of abnormal blood cells. The American Cancer Society estimates that 12,330 new cases of acute myeloid leukemia (AML) will be diagnosed and approximately 8,950 deaths from AML will occur in the U.S. in 2010. AML is generally a disease of older people, with the average patient age at onset of approximately 67 years. There remain a substantial proportion of elderly patients who do not receive intensive chemotherapy due to their inability to tolerate such regimens, and other risk factors. Therefore, there is a significant unmet medical need in developing a well-tolerated and effective treatment for these patients.

About Tosedostat

Tosedostat is an orally dosed aminopeptidase inhibitor which blocks the M1/17 family of aminopeptidases. Disrupting aminopeptidases deprives sensitive tumour cells of amino acids by blocking protein recycling, resulting in tumor cell death. Tosedostat has been studied in Phase I-II clinical trials both as a single agent and in combination with other chemotherapeutic agents. Such studies have demonstrated significant anti-tumour response without the typical side effects of conventional, non-targeted cytotoxic therapies. Initial target indications include AML, MDS and multiple myeloma.

About Chroma Therapeutics

Chroma Therapeutics, based in Oxford (UK), is a drug discovery and development company focused in the fields of oncology and inflammatory disorders. Chroma is building a broad pipeline of first- or best-in-class treatments utilising its expertise in chromatin biology and its novel intracellular accumulation technologies, which include the ability to selectively target drugs to macrophages. Chroma is backed by a number of leading specialist investors, including Abingworth, Essex Woodlands, Gilde, Phase4 and The Wellcome

Trust. More information about Chroma can be found at www.chromatherapeutics.com.

About Cell Therapeutics, Inc.

Headquartered in Seattle, CTI is a biopharmaceutical company committed to developing an integrated portfolio of oncology products aimed at making cancer more treatable. For additional information, please visit www.CellTherapeutics.com.