Ive been on Sprycel for 2 years. The first year I got down to 9% pcr levels and then my platelets started getting low. I did a bone marrow biopsy and I didn't have any mutations and no more blasts so I'm still in chronic phase. The doctor said I was just sensitive to sprycel at 100 mg per day. We found a the right dose at 25 mg per day and I'm good and jogging and back to normal life. I feel great. the problem is my pcr levels just wont go any lower than 23%. the problem is if I switch TKIs I might be sensitive to those as well. So I'm just staying on sprycel for now. I may up my dose to see if I can get my levels down. but at least my disease isn't progressing. any experience with this?