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Imatinib resistance

Hi All

Me again and sorry for asking lots of questions recently, i promise i will be quiet soon ha ha. Ok as i posted previously my last bone marrow was showing that i was still at 20% and my last pcr was showing a rise from 5% to 7% basically what does this mean? does it mean that i have become resistant to imatinib? Also if i am resistant to imatinib what are my chances on nilotinib? I've been looking around the forum and keep reading a bit on the T35i mutation could this be why the imatinib has stopped lowering my pcr's or could i just be a slow responder?

I know i am asking a lot of questions and it looks like i will be changing to nilotinib shortly i'm just waiting for my new pcr results to come back, but i want to try and understand as much as possible as the more i keep thinking about the rising pcr the more i am worrying and the wait for the results are a nightmare as we can all sympathise with i'm sure.

Thanks again
Ni x

Hi Naomii,

T315i is the ultimate multi-drug resistant mutation and if you had it I am sure it would have been identified already.
There are other IM resistant mutations- which is why nilotinib and dasatinib were developed. Both these TKI's the other resistant mutations- apart from T315i.

Ponatinib ( a new TKI manufactured by Ariad and presently in clinical trial) does have an effect on T315i. This is very exciting and is the only TKI that has such activity.

There can be many reasons for a sub-optimal response to IM... but nilotinib and dasatinib are very effective.

My pcr was rising for about 10 months before I had my sct because I had an IM mutation Y235H but imatinib continued to have some control so that I could consider my options - eventually I opted for a mini transplant. (2nd Gen TKI's were not available in UK at that time)

So try not to worry too much about your pcr suddenly jumping and your disease progressing.
...........given the excellent data for nilotinib you would do well to change.

Sandy

Thanks Sandy I feel a bit better now, just hate all the waiting as i am sure we all do

Ni x