Dr. Kay points out the obvious. The longer that we are on a medication, the more likely we are to see a resistant sub clone emerge, take over and become dominant.
Will this be a significant story or an infrequent and unfortunate sidebar to a story of success as we learn more from those few of us who are entering our second and third and maybe fourth year of ibrutinib and idelalisib? There are hints of some danger in the emerging data.
Will the dreaded Kaplan Meier curves continue to trend down or will they plateau? How big an issue will Richter's Transformation become?
Those unanswered questions are precisely why the pioneers who entered these trials early on need to continue to be followed in extension trials (but we should get less frequent CT scans please- that's a whole other topic).
Dr. Kay correctly reminds us that CML is a more complicated and smarter cancer than CML and that is not a good thing. Accordingly, the treatment paradigms of very long term therapy that were developed for imatinib (Gleevec) and its ilk may not necessarily work in CLL.
This discussion circles back to my much commented on prior post about the need for us to start looking at mop up therapies for those of us in deep remissions with the new agents, but with residual lingering disease.
I believe Dr. Kay is making my point for me.
Here is Dr. Kay:
What do you think of his proposal to get in and get out as quickly as possible?
For me, quick might be defined as one or two years of signal inhibitor therapy, and my ideal mop up would involve no chemo.
Let me know what you think by email or by posting a comment. Remember if you leave a comment I do not have your contact information unless you include it in the comment.