In her important ASCO 2014 abstract, Dr. Susan O’ Brien, who started at the University of California at Irvine (UCI) on Jan. 1, 2015, describes the astonishingly good data for those patients with chronic lymphocytic leukemia (CLL) lucky enough to get frontline ibrutinib, and for the over-65 crowd. These data provide a strong argument in favor of moving it and other drugs such as idelalisib or ABT-199 upfront. In this trial, in the treatment-naive arm, there was one early progression with Richter’s that was probably present before the trial began, and the rest of the cohort remains in the happy land of progression free survival or PFS. During the interview, Dr. O’Brien shares the three-year follow-up data on single agent ibrutinib in relapsed and refractory patients and in the elderly.
The data is still very good for the difficult to treat relapsed and refractory group, but the curve is not flat. Relapses happen. This is especially true for those of us like me with the dreaded 17p deletion, where half the patients have started to progress after a little more than two years. While this is clearly much better than anything else out there in this most challenging population, ibrutinib has not hit a home run for this group as it may have for the treatment-naive patients. (We now suspect from data presented at ASH 2014 that having a complex karyotype may be the real driver of relapse and resistance.)
Despite significant recent progress, effective long-term therapies for relapsed 17p deletion still remains one of the more pressing unmet needs in the world of CLL.
Dr. O’Brien discusses what these relapses look like, and mentions a strategy that I would strongly consider, namely that even at the time of relapse, that one should stay on ibrutinib until a new therapy is begun. The BTK inhibitor in ibrutinib, even it is no longer irreversibly binding, it is still partially braking the disease progression.
If you can get past the hisses and pops on an audio recording, you will get to hear some pretty exciting news from Dr. Susan O’ Brien who incidentally ieft MD Anderson after many years of important CLL-related research and compassionate patient care to head up a cancer research team and consult on CLL patients in my backyard at the University of California at Irvine (UCI).
Let’s listen to Dr. O’Brien.
Dr. Brian Koffman 11/30/2014 updated 3/20/15