It looks like you are finally getting good control of your patient’s disease with nilotinib after 12 years but her BCR::ABL1 values are still not in the MR4.5 range. While a TFR attempt would be tempting I don’t think she would have a great chance of success at this stage given her imatinib treatment failure, a KD mutation and lack of prolonged MR4. On the other hand continuing her nilotinib therapy – even at the lower dose is starting to get quite risky from a cardiovascular perspective. Exposure of more than 5 years of nilotinib is associated with high rates of arterial occlusive events, even for patients who were low risk for CVS disease initially.
The options here would be to lower her nilotinib dose further to 300 mg daily, switch to low dose dasatinib (50 mg/day) or switch to asciminib 80 mg daily. You could argue that it would be better to wait until she is in the MR4.5 range before making any change but I am more concerned about vascular events after such a long exposure to full dose nilotinib, so I would probably make a change now. Personally, I would switch her to asciminib but I am not sure if that is possible in NZ in this setting. If not I would probably switch to low dose dasatinib. If the preference of the patient is to remain on nilotinib then I would go for a lower dose.