I understand that dosage amount may not cause resistance. But what does cause resistance? I guess erratic adherence?
My opinion: (based on reading and no training or professional research)- yes, spotty adherence, absorption, physiological traits of the bonding points, disease' ability to adapt, and dietary habits, supplements and other medications....(somebody's welcome to correct me on phrasing or any of that)...that said, it would be contradictory, to then say lowering dose COULDN'T cause resistance, because several of those items' premise for causing resistance relates to the amount of drug making its way to the blood stream and then to its target site, and then being potent enough to be effective in its intended purpose.
If these cells are living, which they are, it would make complete sense in this layman's mind, that routinely subjecting these cells to an environment, (our blood) that isn't necessarily "hospitable", but not toxic (saturated with tki) , could allow or provoke the diseased entities to adapt/mutate to obtain survival.
Those of us concerned or passing blame for the disease toward benzene and radiation exposure, might embrace this idea more, as this would likely be how the disease initiated. Repeat exposures- although not enough or potent enough to kill us immediately, were enough to cause a mutation, and the disease..
Possibly those with lower disease amounts within their bodies, are successful on lowering dosage, because the ratio remains correct of drug:disease. If someone with more leukemia stem cells or more active ones, reduced dosage, it might not "keep up" ? I don't know. So once at pcru or very, very low, the disease amount is lessened, and likely to a point that the drug:disease ratio can be sustained fine with a lower dose, but it is pretty much a guess what that "safe dose" is.
So me, with my paranoia and logic, (and slower initial response) will elect to stay on a recommended dose of a tki, so long as it's safe, viable and attainable, without argument.
3/25/2015- Dx'ed by FISH : 85% of cells dual-fusion signals, 7% with tri-fusion signals, WBC 212,000. Started Gleevec 400mg.... Calculated .93 SOKAL
08/17/2015- 14.793 % I.S P210 (quest)
10/15/2015- 3.313 % I.S (quest)
12/23/2015- 1.891 % I.S (quest)
1/07/2016- Tasigna 300mg 2x daily
1/14/2016- 4.414 % I.S P210- City Of Hope lab, mutation negative.
1/26/2016- 1.589 % I.S (quest)
2/22/2016- 1.719 % I.S (quest)
2/29/2016- 1.133 % I.S (quest)
3/03/2016- Tasigna 400mg 2x daily.
3/29/2016- 0.663 % I.S (quest)
4/27/2016- 0.781 % I.S (quest)
5/04/2016- 0.652 % I.S.(quest)
5/24/2016- 0.501 % I.S (quest)
6/28/2016-0.534 % I.S (quest)
7/15/2016-0.881 % I.S (quest)
7/22/2016- Bosulif 500mg
7/28/2016- t315i test- Negative
8/22/2016-0.432 % I.S (quest )
11/15/2016-0.325 % I.S (quest)
2/1/2017- .0445% i.s (genoptix)
5/6/2017- .0968% i.s (genoptix)
5/12/2017- .12 % i.s (quest).
6/4/2017- .083% i.s (quest)
6/11/2017- .0295% i.s (genoptix)
8/5/2017- .0501% i.s (genoptix)
11/6/2017- .0270% i.s (genoptix)