MELBOURNE, Australia, and MENLO PARK, California U.S.A. (June 11, 2007). ChemGenex Pharmaceuticals Limited (ASX:CXS and NASDAQ:CXSP) announced today the publication of a report in the prestigious Nature publication Leukemia confirming the positive clinical activity of the company's lead compound, Ceflatonin against Gleevec-resistant, chronic myeloid leukemia (CML) associated with the T315I Bcr-Abl mutation.
The T315I mutation is known to confer resistance to both Gleevec (imatinib mesylate) and second-generation tyrosine kinase inhibitors (dasatinib and nilotinib). Recent publications indicate that the incidence of T315I-associated resistance is increasing and confirm that this mutation is likely to become the prevalent mutation in those who fail tyrosine kinase inhibitor therapy.
The publication by Dr. Laurence Legros of the Hpital Archet, Nice, France and colleagues describes the treatment with Ceflatonin (homoharringtonine, HHT) of a Gleevec-resistant, chronic-phase CML patient with the T315I Bcr-Abl mutation. The authors report that the patient experienced a 50 percent reduction of T315I Bcr-Abl levels within 2.5 months of treatment initiation, and the complete disappearance of the mutation within 5.5 months of treatment. Complete hematological response (CHR) was achieved after three cycles of therapy.
Based on the clinical results, the authors believe that the rapid and complete disappearance of the T315I mutation might suggest a particular sensitivity of this mutation to HHT. The authors conclude that HHT "may provide an alternative therapeutic treatment option for CML patients with the T315I mutation, for whom therapies have been previously lacking."
The authors also noted some hematologic toxicities (neutropenia, thrombocytopenia and anemia), but confirmed that the toxicity of HHT was "easy to manage".
"We are delighted with this publication that reinforces our belief in the potential of Ceflatonin to treat patient
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Contact: Joan Kureczka
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Kureczka/Martin Associates
11-Jun-2007