Your medication Gleevec (Imatinib) is a type of cancer growth blocker called a tyrosine kinase inhibitor (TKI). Tyrosine kinases are proteins that cells use to signal to each other to grow. They act as chemical messengers. There are a number of different tyrosine kinases and blocking them stops the cancer cells growing. This medication "control" the growth of the bad cells until the cells mutate and the medication becomes ineffective. The good news is that there are new medications being developed which may be released in 3 to 5 years? These medication use BCL2 to attack the WBC mitochondria to inactivate those cells. The good thing about your medication is it does not attack healthy organs or cells and the next generation will only attack bad cells. I hope you are eating healthy and exercising to keep by body fit for longer happier and healthier days.