I am flabbergasted at your Oncs assessment of Tasigna in relation to other TKI drugs. I've never heard anyone say anything even remotely close. It sounds like a bit of a hike, but I would make the trip to Mayo. You don't have to transfer your care there, just call them, explain your situation and tell them you want to see a CML specialist for a second opinion. When you are there, you can ask the specialist if they can recommend anyone locally for you to work with. Most people have a local oncologist to run their labs and check them out and they go see the specialist once or twice a year.
Good that the liver enzymes are coming down, although not surprising, Tasigna is strong and it can hit hard, for most they get used to it and when they go back on the levels stay in acceptable range. If not, I wouldn't fear, there are other options. regardless of what you have been told.
You may want to read this, although it is a bit technical, perhaps your doctor should read it as well
The use of nilotinib or dasatinib after failure to 2 prior tyrosine kinase inhibitors: long term follow-up
"With the availability of imatinib, nilotinib, and dasatinib, a
scenario seen with increasing frequency is that of patients who
have failed imatinib and one of the second-generation TKIs. The
other second-generation TKIs are usually considered viable alternatives
for therapy, and preliminary results suggest that some patients
may indeed respond to a second-generation TKI used as third-line
therapy.15,16 However, the long-term benefit of such an approach is
largely unknown. In this study, we report the response rates and
long-term results of using a second-generation TKI after failure to
imatinib and another second-generation TKI."
"Withthe availability of 2 of these agents, nilotinib and dasatinib, it has
become an increasingly common practice to use one of these agents
when patients have failed imatinib and the other second-generation
TKI. Early data have suggested that this strategy may be of benefit
to some patients."
"Another study reported a hematologic and
cytogenetic response rate of 57% and 30%, respectively, among
23 patients with CML in all phases treated with dasatinib after
having failed imatinib and nilotinib"
A couple of things to note
1) nilotinib is the generic name for Tasigna
2) dasatinib is the generic name for Sprycel
3) TKI is a Tyrosine Kinase Inhibitor, which is the class of drugs we take. Gleevec, Tasigna, and Sprycel are all TKI drugs.
4) This study does not take into account bosutinib and ponatinib. Bosutinib and ponatinib are trial drugs that are going up for FDA approval. Both drugs are expected to be on the market in the next year or two. I assure you people who fail Tasigna will be prescribed other agents.
Best of luck