The Outcomes of Chronic Myeloid Leukemia Patients With Molecular Warning Responses During Imatinib Treatment According to the European LeukemiaNet 2013 Recommendations.

In the European LeukemiaNet (ELN) 2013 recommendations, chronic myeloid leukemia (CML) patients with warning response (WR) were suggested to be monitored closely continuing with the same tyrosine kinase inhibitor (TKI). Differently, the guidelines of the National Comprehensive Cancer Network considers switching to another TKI as an option. We retrospectively evaluated 73 CML patients receiving first-line imatinib, who were followed and managed in accordance with ELN recommendations. We compared patients with molecular WR with patients with optimal response (OR) and failure regarding short- and long-term outcomes. The cumulative major molecular response (MMR) rates in patients with OR were significantly higher at any time point than those achieved by the WR group. Patients with WR at 3 months had significantly inferior failure-free survival (FFS) than optimal responders, but overall survival (OS) was similar. For 6 and 12 months, the WR and OR groups had similar FFS and OS. Twenty of 23 patients with WR at 12 months achieved MMR during imatinib treatment. It takes longer to get to ELN time points with imatinib than second-generation TKIs (2GTKIs). Treatment might fail in a small proportion of the patients with WR during imatinib treatment, but close and careful monitoring and timely switching to 2GTKIs might translate into favorable outcomes. Avoiding early switch to 2GTKIs would prevent patients from experiencing potential toxicities. There is still a need for prospective comparative studies (ie, continuing imatinib treatment vs. switching to 2GTKIs) in patients with WR, to justify the validity of this response category and to explore the benefit of treatment change in these patients.

Soysal T ，Eskazan AE ，Serin I ，Sadri S ，Keskin D ，Ozgur Yurttas N ，Berk S ，Erdogan Ozunal I ，Salihoglu A ，Ar MC ，Ongoren S ，Baslar Z ，Ozbek U ，Aydin Y ... -  《-》

Generic imatinib in the treatment of chronic myeloid leukemia: two years' experience in Latvia.

Lejniece S ，Udre I ，Rivkina A 《-》

A prospective analysis of clinical efficacy and safety in chronic myeloid leukemia-chronic phase patients with imatinib resistance or intolerance as evaluated using European LeukemiaNet 2013 criteria.

We conducted a phase II study to evaluate the efficacy and safety of dasatinib in Japanese patients with imatinib-resistant or imatinib-intolerant chronic myeloid leukemia (CML). From 2009 to 2011, 54 CML-chronic phase (CP) patients with resistance (n = 40) or intolerance (n = 25) to imatinib were registered to undergo dasatinib treatment. Eleven patients showed both resistance and intolerance to imatinib. Coincidentally, the resistance criteria in this study were the same as a non-optimal response to tyrosine kinase inhibitors (TKIs) as defined in the European LeukemiaNet (ELN) 2013 recommendations. The overall incidence rate of major molecular response (MMR) at 12 months was 62.3% (n = 47). Forty patients with resistance to imatinib who were 'warning' and 'failure' patients based on the ELN 2013 recommendations were assessed; cumulative MMR and MR(4.5) rates were 62.5% (n = 39) and 21.0% (n = 40), respectively, at 12 months. Twelve patients who showed a BCR-ABL transcript level >1% on the international scale did not achieve a MMR or discontinued dasatinib treatment because of insufficient effects. With regard to safety issues, grade 3/4 non-hematologic adverse events (AEs) were infrequent. Patients with non-optimal responses (who meet ELN 2013 warning and failure criteria) to imatinib should be switched quickly to dasatinib, which is less toxic in CML-CP patients, to improve their prognoses. A BCR-ABL1 IS of <1% at 3 months of dasatinib administration is a landmark for good therapeutic outcome.

Murai K ，Akagi T ，Shimosegawa K ，Sugawara T ，Ishizawa K ，Ito S ，Murai K ，Motegi M ，Yokoyama H ，Noji H ，Tajima K ，Kimura J ，Chou T ，Ogawa K ，Harigae H ，Kubo K ，Oba K ，Sakamoto J ，Ishida Y ... -  《-》

Switching to second-generation tyrosine kinase inhibitor improves the response and outcome of frontline imatinib-treated patients with chronic myeloid leukemia with more than 10% of BCR-ABL/ABL ratio at 3 months.

Chronic myeloid leukemia patients display heterogeneous responses to imatinib. Survival depends on baseline clinical characteristics (including prognostic scoring systems) and on early response (such as >10% BCR-ABL/ABL ratio at 3 months of therapy). The results of switching to second-generation tyrosine kinase inhibitors (2GTKIs) may contain a bias since, in the majority of these studies, patients who switch treatment due to intolerance or failure are censored or excluded. We analyzed the Spanish Registry data on switching in an intention-to-treat analysis of patients in standard clinical practice. Switching to 2GTKIs improves responses from 45% to 75% of complete cytogenetic response (CCyR) and from 15% to 45% of major molecular response (MMR) in the group without molecular response 1 (MR1) at 3 months and from 70% to 87% in CCyR and from 52% to 87% in MMR in the group with MR1. The final response rate is poorer in the group with no MR1 at 3 months. Nevertheless, the differences in the rates of response were not translated into differences in major events (transformations or deaths), and the final progression-free survival and overall survival were similar.

Casado LF ，García-Gutiérrez JV ，Massagué I ，Giraldo P ，Pérez-Encinas M ，de Paz R ，Martínez-López J ，Bautista G ，Osorio S ，Requena MJ ，Palomera L ，Peñarrubia MJ ，Calle C ，Hernández-Rivas JÁ ，Burgaleta C ，Maestro B ，García-Ormeña N ，Steegmann JL ... -  《Cancer Medicine》

Discontinuation of tyrosine kinase inhibitor therapy in chronic myeloid leukaemia (EURO-SKI): a prespecified interim analysis of a prospective, multicentre, non-randomised, trial.

Tyrosine kinase inhibitors (TKIs) have improved the survival of patients with chronic myeloid leukaemia. Many patients have deep molecular responses, a prerequisite for TKI therapy discontinuation. We aimed to define precise conditions for stopping treatment. In this prospective, non-randomised trial, we enrolled patients with chronic myeloid leukaemia at 61 European centres in 11 countries. Eligible patients had chronic-phase chronic myeloid leukaemia, had received any TKI for at least 3 years (without treatment failure according to European LeukemiaNet [ELN] recommendations), and had a confirmed deep molecular response for at least 1 year. The primary endpoint was molecular relapse-free survival, defined by loss of major molecular response (MMR; >0·1% BCR-ABL1 on the International Scale) and assessed in all patients with at least one molecular result. Secondary endpoints were a prognostic analysis of factors affecting maintenance of MMR at 6 months in learning and validation samples and the cost impact of stopping TKI therapy. We considered loss of haematological response, progress to accelerated-phase chronic myeloid leukaemia, or blast crisis as serious adverse events. This study presents the results of the prespecified interim analysis, which was done after the 6-month molecular relapse-free survival status was known for 200 patients. The study is ongoing and is registered with ClinicalTrials.gov, number NCT01596114. Between May 30, 2012, and Dec 3, 2014, we assessed 868 patients with chronic myeloid leukaemia for eligibility, of whom 758 were enrolled. Median follow-up of the 755 patients evaluable for molecular response was 27 months (IQR 21-34). Molecular relapse-free survival for these patients was 61% (95% CI 57-64) at 6 months and 50% (46-54) at 24 months. Of these 755 patients, 371 (49%) lost MMR after TKI discontinuation, four (1%) died while in MMR for reasons unrelated to chronic myeloid leukaemia (myocardial infarction, lung cancer, renal cancer, and heart failure), and 13 (2%) restarted TKI therapy while in MMR. A further six (1%) patients died in chronic-phase chronic myeloid leukaemia after loss of MMR and re-initiation of TKI therapy for reasons unrelated to chronic myeloid leukaemia, and two (<1%) patients lost MMR despite restarting TKI therapy. In the prognostic analysis in 405 patients who received imatinib as first-line treatment (learning sample), longer treatment duration (odds ratio [OR] per year 1·14 [95% CI 1·05-1·23]; p=0·0010) and longer deep molecular response durations (1·13 [1·04-1·23]; p=0·0032) were associated with increasing probability of MMR maintenance at 6 months. The OR for deep molecular response duration was replicated in the validation sample consisting of 171 patients treated with any TKI as first-line treatment, although the association was not significant (1·13 [0·98-1·29]; p=0·08). TKI discontinuation was associated with substantial cost savings (an estimated €22 million). No serious adverse events were reported. Patients with chronic myeloid leukaemia who have achieved deep molecular responses have good molecular relapse-free survival. Such patients should be considered for TKI discontinuation, particularly those who have been in deep molecular response for a long time. Stopping treatment could spare patients from treatment-induced side-effects and reduce health expenditure. ELN Foundation and France National Cancer Institute.

Saussele S ，Richter J ，Guilhot J ，Gruber FX ，Hjorth-Hansen H ，Almeida A ，Janssen JJWM ，Mayer J ，Koskenvesa P ，Panayiotidis P ，Olsson-Strömberg U ，Martinez-Lopez J ，Rousselot P ，Vestergaard H ，Ehrencrona H ，Kairisto V ，Machová Poláková K ，Müller MC ，Mustjoki S ，Berger MG ，Fabarius A ，Hofmann WK ，Hochhaus A ，Pfirrmann M ，Mahon FX ，EURO-SKI investigators ... -  《-》