Mathematical Model Could Support Drug Therapy

In a recent study combining math and medicine, researchers state that patients with chronic myelogenous leukemia (CML) may be cured with an optimally timed cancer vaccine, where the timing is determined based on their own immune response.

The scientists developed a mathematical model that could increase chances for long-term remission in individual patients. The study took into account the patient's natural immune response in conjunction with the effects of drugs that have been successful in putting CML patients into remission.

Over four years, data was collected from CML patients. The scientists measured the strength of each patient's immune response, in the form of the numbers and the activity of the anti-leukemia T cells, at different times during the drug therapy.

The researchers concluded that it is not only the drug that sends the leukemia into remission but also the natural immune response. After starting the drug treatment, the anti-leukemia immune response gradually increases. However, it begins to weaken after it reaches a peak. This, according to the scientists, typically happens well into the treatment.

Leukemia cells are still present, they explain, but in relatively low numbers that causes the immune response to wind down. This is an ideal time for the cancer cells to develop drug resistance. The model suggests that the immune response of the patients should be boosted exactly at the time when their immune response starts weakening.

The authors further suggest that stimulation could be provided in the form of "vaccines" in which pre-therapy blood taken from patients is irradiated to kill active cancer cells, then introduced back to the patient. A strong stimulation of the immune system was shown to be active in vitro in lab experiments.

But the dynamics of each patient's immune response differ. That's where the math comes in, so the researchers. By measuring each patient's parameters to find when the dosage will be most effective and combining them with the mathematic model they want to tailor the treatment to the patient. But first, the theory has to be tried on animal models.; Source: University of Maryland