Cell Therapeutics, Inc. (CTI) and Chroma Therapeutics Ltd. (Chroma) 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-tumour responses in blood related cancers and solid tumours in phase I-II clinical trials.

CTI, in collaboration with Chroma, expects to commence a phase III clinical study in the United States and Europe in elderly patients with relapsed or refractory Acute Myeloid Leukaemia (AML) for potential approval by the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). The FDA and the EMA have granted tosedostat orphan drug status for AML.

Pursuant to the terms of the agreement, CTI will make an upfront payment 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, Myelo-Dysplastic Syndrome (MDS) and certain other indications, as well as royalties on net sales in CTI's territories.

CTI will oversee development operations and commercialization 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.

“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 tumour survival,” commented James A Bianco, MD, CEO of CTI. “In initial 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.”

Chroma is an Oxford, UK based private company led by a management team with extensive public biotechnology and large pharmaceutical company experience, including former executives of Celltech, British Biotech, AstraZeneca and Roche, and backed by leading specialist investors. Chroma is focused on harnessing chromatin biology and its novel cell accumulation (ESM) technology to develop new targeted therapies for cancer and inflammatory disorders.

“We believe that this is a collaboration that should enable the rapid progression of tosedostat toward seeking regulatory approval, given CTI's development and commercialization 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 medical needs where tosedostat could provide an important therapeutic advance for patients if approved.”

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 AML will be diagnosed and approximately 8,950 deaths from AML will occur in the US in 2010. AML is generally a disease affecting 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.

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 tumour cell death. Tosedostat has been studied in Chroma's phase I-II clinical trials both as a single agent and in combination with other chemotherapeutic agents. Such studies have demonstrated significant anti-tumour responses without the typical side effects of conventional, non-targeted cytotoxic therapies. Initial target indications include AML, MDS and multiple myeloma.

CTI is a biopharmaceutical company committed to developing an integrated portfolio of oncology products aimed at making cancer more treatable.

Chroma Therapeutics, based in Oxford (UK), is a drug discovery and development company focused in the fields of oncology and inflammatory disorders.