You are here

Taking the TFR Plunge

I was Dx in September 2016, reached MMR in 82 days and have been >MR.4.5 since April of 2017 all while reducing my Tasigna dose 3 times, the last reduction in September of 2017 to 150 mg 1x/day, 25% of starting dose.  The dose reductions were due to multiple nasty side effects that have mostly subsided.  Heart palpitations have continued but have been helped by beta blocker but that has caused GERD induced cough for which my primary doc prescribed Pepcid.  So I keep adding medicines to counter the side effects of the last medicine added and the merry-go-round just continues.  I am incredibly grateful for the rapid and deep response that I have had, but I want my pre-CML life back if I'm lucky enough to get it.

I just had my 6 month PCR which was undetected. I met with my oncologist this morning and he all but ordered me to try TFR.  Mind you, this was the same doctor with whom I fought tooth and nail for 2 months to get his blessing to do my first dose reduction in March 2017. So after thinking about it and talking to my wife, I have decided to try TFR.  Tomorrow will be my first day without a TKI since October 5, 2016. I don't like the idea of monthly PCR's, but I also don't like the idea of not knowing if TFR will work for me or not, so the only option is to try it. I have a bunch of irrational fears but I also understand the science and know that there is virtually no risk to trying.

Enough of my rambling - wish me luck.

CMLJAX - Oustanding! I will be right behind you with my second TFR attempt in September.

We wish you luck.

Wishing you all the best. Please keep us posted

Wishing you all the luck, please keep us posted. 


Fantastic good luck for a successful TFR, I hope to try later this year, dx 2015 took Tasigna for 4yrs,changed to Dasatinib a year ago because couldn't handle side effects any more, Dasatanib has been great so far.

Wishing you the best of luck in your TFR journey!


Wishing you every success in your trial for TFR. Did you decide to just stop rather than try a period of dose reduction? 


Hi Sandy:

I reduced dose 3 times in 2017 from 600 mg/day to 150 mg/day. Since I was already at this very low dose, I just stopped. 

Unfortunately my PCR yesterday jumped from negative to .004% in just 7 weeks off the TKI.  This is the first time since March of 2017 that I have been worse than at least MR 4.5. While this is not technically a failure of TFR, I have decided to restart Tasigna at my last dose, 150 mg /day.  In retrospect, I should have heeded the words of Professor Clark who ran the Destiny study:

Both the EUROSKI and our own data show a lower recurrence risk on stopping with longer duration of treatment, and this is a continuum – in other words the longer the better and there is no magic threshold of treatment duration such as 3 or 5 years. EUROSKI suggested a 16% increase/decrease in recurrence rate with one less/more treatment year either side of 5 years. In DESTINY the data are a little preliminary, but appear to show a mean decrease in recurrence of ~8% per additional treatment year over the 3-10 year range of treatment duration; however the recurrence rate for treatment duration of only 3 or 4 years is at least 50%, compared with under 30% thereafter.

I had only been on treatment for 3 years and 9 months, so despite my oncologists encouragement to try TFR, I should have waited another 4 - 5 years.

It was nice being on a 6 month testing schedule, but that's now gone until I regain and sustain at least MR 4.5, which I am hoping I will do fairly quickly.  I don't mean to discourage others from trying TFR, rather follow the science.  I didn't and am disappointed in myself for thinking I could beat the odds.


I would suggest it might be worth giving TFR another month and see how it is then. 0.004% is a very low level. I'd also check that your lab haven't got some new more sensitive equipment which can detect a level that previously could not be detected. If it trends up again then back on the pills; If it stabilised at that 0.004% you would do fine. 

Thanks Alistair - I had the same thought, but I decided to chicken out.  My lab did not change its sensitivity - still at .0032, so I went from undetected to .004, which could be multiple logs - who knows.  Whatever the log increase, it's a lot in just one month (my first test was 3 weeks after quitting and it was still undetected).

CMLJAX wrote, "so I went from undetected to .004, which could be multiple logs ..."

Undetected is just that - no bcr-abl detected. 0.004 is not meaningful - and going from undetected to 0.004 is not a two log increase. 0.004 is still indistinguishable from "undetected" in terms of PCR technology and the precision of the test. ANY value less than 0.01% or essentially that third decimal place is meaningless. At M.D.Anderson, they don't even report beyond two decimal places for that reason. There is something about doctors and decimal places. It's like calculating the value of Pi **: 3.1415926535 8979323846 2643383279 5028841971 ..... any decimal value past 3.14 is pointless. But for some reason I still remember 3.14159 .... 3.14 is fine and so is two decimal places for bcr-abl results!

It is important to note that at 0.1% - more than two logs above where you are - this is Major Molecular Remission (MMR) meaning very little residual disease and a major milestone achievement for CML patients. You are off drug and were detected more than 2.5 logs lower than this already very very low number.

We like to think PCR numbers are all the same along the scale from 100% down to "undetected", but the reality is they are not. Accuracy is not the same. The lower the number the higher the error range in the measurement.

It seems you made your decision on resuming therapy and that's fine. But chances are your result was just noise. In PCR testing, trends are what are important and then only once they cross over the 0.01% threshold. A good rule of thumb is test 3 times to establish trend.*

(*an exception to the 3 test rule would be a multiple log jump above 0.1%)