News & Events

ChemGenex Pharmaceuticals Limited (ASX:CXS) announced today the presentation of updated clinical data showing that OMAPRO™ (omacetaxine mepesuccinate) produced durable hematologic and cytogenetic responses in a significant proportion of chronic phase chronic myeloid leukemia (CML) patients, who had failed previous attempts to control their disease with two or three FDA-approved tyrosine kinase inhibitors (TKIs). The new data were presented at the 52nd Annual American Society of Hematology Meeting in Orlando, Florida (ASH).

At the CML therapy poster session Dr. Jorge Cortes MD, Chair, CML Section, Department of Leukemia, Division of Cancer Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas, and a lead investigator in ChemGenex’s clinical studies, presented a poster on behalf of ChemGenex and a team of investigators from leading international clinical research centers concluding that OMAPROTM represents a new potential therapy for patients with multi-TKI resistant CML.

Data were presented from 61 evaluable CML patients in chronic phase (defined as those who had been adjudicated by an independent Data Monitoring Committee (DMC) and had a bone marrow report available for cytogenetic assessment). Highlights of the data were:

• Major cytogenetic response (MCyR) rate of 33% in patients who had failed 2 TKIs – these patients failed imatinib and were also resistant to dasatinib or nilotinib
•  MCyR rate of 20% in patients that had failed 3 TKIs – these patients failed imatinib and were also resistant to dasatinib and nilotinib

Data were also presented from the complete group of 85 chronic phase CML patients analyzed on an intent to treat (ITT) basis. Highlights of the data were:

• Overall MCyR rate of 20% with a median duration of response of 7.4 months (range 0.9 - 26+)
• Overall Complete hematological response (CHR) rate of 73% with a median duration of 8.2 months (range 0.7 - 42+)
• Median Overall Survival of 30 months

The most commonly reported (>5%) grade 3/4 treatment-emergent adverse events in the larger, 85 CML chronic phase ITT population were thromobocytopenia (64%), anemia (34%), neutropenia (47%), febrile neutropenia (14%), leukopenia (21%), lymphopenia (18%), pancytopenia (9%) and bone marrow failure (11%) and fatigue (5%). Grade 3/4 events were infrequent and managed by decreasing the days of dosing per cycle.

“We are very pleased with the data presented today that reveals the potential clinical benefit OMAPROTM could have for a significant number of CML patients who, at present, have very limited treatment options,” said Greg Collier, Ph.D., Managing Director and Chief Executive Officer of ChemGenex. “We would like to thank Dr. Cortes and all of our investigators for their efforts to produce this data.

ChemGenex plans to file a New Drug Application for OMAPROTM for the treatment of CML patients who have failed two or more approved TKIs.