Personalized medicines are customized drugs, tailored to a patient's genes, and those that are designed to work far more efficiently and with reduced side effects. Approved drugs such as the billion dollar anti-breast cancer drug, Herceptin, are a good example of an effective personalized medicine.
The article published in Blood stresses on the need for personalized medicines to treat cancers, which have limited treatment options, such as chronic myeloid leukemia (CML).
CML is cancer of the blood and bone marrow. Here there is an overproduction of undifferentiated white blood cells. Though there are effective treatments for some patients, there is no cure for CML.
Leukaemia can develop in anyone, of any age, at any time. CML specifically is most likely to occur over the age of 50. In 2006, approximately 2,869 Australians are projected to have been diagnosed with leukemia; the equivalent of 8 people every day according to the Australian Leukemia Foundation.
The first line of treatment for the majority of CML cancer patients is a drug called Gleevec. Yet, an increasing number of CML patients are developing resistance to Gleevec. As it is becoming less effective in keeping the cancer under control, there is a need for an alternative therapy.
Scientists have new evidence to show that resistance to Gleevec and similar drugs is caused by a particular genetic mutation (T315I mutation) associated with the cause of CML. This mutation is becoming increasingly common in patients. The challenge has been to find a personalized medicine that can fight off cancer caused by a specific genetic mutation.
In the October Blood publication, an accelerated stage CML patient who had developed a resistance to Gleevec therapy as a result of the T315I mutation was successfully treated with Ceflatonin. After ten months of therapy, genetic tests revealed that the patient's level of T315I genetic mutation decreased from 100 per cent to 27 per cent and the patient's health improved.
Ceflatonin is a new personalized therapy for CML patients in development by an Australian-US biotechnology company called ChemGenex Pharmaceuticals. It is currently being tested in patients in clinical trials, which are due for completion next year.
Says Dr Greg Collier, the Australian scientist who heads up ChemGenex: "We have strong evidence that Ceflatonin works via different mechanisms to the current therapies and provides a promising alternative for the growing CML patient populations".
In a futuristic scenario, doctors would take a saliva swab and place it on a gene chip diagnostic to test for the T315I gene mutation. Immediate DNA test results would determine whether the CML patient tests positive for T315I and is suitable for the Ceflatonin therapy. "This would be personalized medicine at its best," says Dr Collier.