Although most patients with chronic myeloid leukemia will respond to tyrosine kinase inhibitors, unfortunately some patients will fail to respond. We typically divide these into the primary failures and secondary failures, the patients who never meet the early milestones or those patients who have achieved a response and then lose the response. The most common reason why patients do not respond to TKIs, one of them is that they do not take medications. If you do not take the medications, you do not have good adherence, you cannot respond. But in the patient who is taking their medications, we think about mutations, and that is where the ABL kinase mutation studies, that we can do off the peripheral blood become important. Other reasons why patients fail to respond? Interactions with other medications such as antacids which inhibit the absorption, or surgeries. So when I see a patient who is not responding, I want to question them–are they taking the medications? Have they started new medications? Have they had some reason why they had to break the medication and not take it or are the genetics starting to change?For more information on managing your patients with CML, and to participate in an interactive case study in which you’ll be able to make clinical decisions for a patient with CP-CML, please view the activity available here.