Stopping treatment: Presentation about the state of play in stopping in the CML satellite symposium at EHA
Francois-Xavier Mahon was presenting about the current state of play in stopping CML treatment at the EHA Satellite Symposium on CML, hosted by Novartis. Here is a brief summary of Jan attending the session just now.
In terms of what we know about stopping Imatinib, Francois-Xavier Mahon presented the data of the first STIM (STop IMatinib) in France, where about 38% were able to successfully stop treatment without having detectable disease with a median follow-up of 65 months. Similar rates were observed in other STIM studies like STIM2 (50% still undetectable at 24 months), TWISTER (47% still undetectable at 24 months), A-STIM (61% without loss of MMR at 36 months), KID (59% without loss of MMR at 24 months), STOP2G-TKI (57% without loss of MMR at 24 months) and DADI (Dasatinib, 48% without PCR rise above 0,0069%), ENESTop (58% without loss of MMR) and EUROSKI (51% without molecular relapse at 24 months). So depending on therapy re-initiation criteria, across studies there seems to be roughly a 50:50 chance that stopping treatment in deep molecular response is successful.
Predictive factors are still unclear. According to EUROSKI data, the frequency for relapse seems to be lower for patients with more than 8 years of TKI treatment, for longer MR4 than 5 years, for patients who received 2nd generation TKI as a first line treatment, and in case of patients that switched treatment, when switch was due to intolerance to the drug and not due to resistance. More issues are under investigation, e.g. immune control of the disease and genetic background of individual patients.
39% of patients in EUROSKI experienced adverse events from stopping in the form of pain in muscles, bones or joints, with 6% in severe forms (grade 3 or 4), and 8% experienced other stopping side effects like sweating, skin disorders, depression, fatigue and weight loss. In ENESTop (Nilotinib-Stop) 53% of patients experienced some form of muscle/bone/joint pain, but only 2% with severe forms.
A recent review article published by Susanne Saußele and other experts in the LEUKEMIA journal on 2 May has published a recommendation what criteria to use when stopping treatment moves into mainstream clinical practice (doi:10.1038/leu.2016.115).
I am sure we will hear more about CML stopping in the plenary, when the first full analysis of EUROSKI data (771 patients – the data presented last year was only an interim analysis of the first 200 patients) will be presented tomorrow at EHA.
-- Jan Geissler, 9 June 2016