Lomustine is beneficial to older AML with ELN2017 adverse risk profile and intermediate karyotype: a FILO study

We previously reported the benefit of lomustine addition to conventional chemotherapy in older acute myeloid leukemias with nonadverse chromosomal aberrations in the LAM-SA 2007 randomized clinical trial (NCT00590837). A molecular analysis of 52 genes performed in 330 patients included in this trial, 163 patients being treated with lomustine in combination with idarubicin and cytarabine and 167 without lomustine, identified 1088 mutations with an average of 3.3 mutations per patient. NPM1, FLT3, and DNMT3A were the most frequently mutated genes. A putative therapeutic target was identified in 178 patients (54%). Among five molecular classifications analyzed, the ELN2017 risk classification has the stronger association with the clinical evolution. Patients not treated with lomustine have an expected survival prognosis in agreement with this classification regarding the overall and event-free survivals. In strong contrast, lomustine erased the ELN2017 classification prognosis. The benefit of lomustine in nonadverse chromosomal aberrations was restricted to patients with RUNX1, ASXL1, TP53, and FLT3-ITD^high/NPM1^WT mutations in contrast to the intermediate and favorable ELN2017 patients. This post-hoc analysis identified a subgroup of fit elderly AML patients with intermediate cytogenetics and molecular markers who may benefit from lomustine addition to intensive chemotherapy.

Outcome of AML patients with IDH2 mutations in real world before the era of IDH2 inhibitors

Describing the prognosis of sub-groups of acute myeloid leukemia (AML) patients treated in real world with current therapies is becoming increasingly relevant to estimate the benefit that new targeted drugs will bring in the field. This is particularly the case when novel drugs are registered on the basis of non-randomized studies. IDH2 inhibitors have recently emerged as promising drugs in patients with IDH2^R140 or IDH2^R172 mutations. Enasidenib, a first-in-class IDH2 inhibitor, has been approved following promising results of a phase 1-2 clinical trial in relapsed or refractory AML patients with IDH2 mutations. In this study, we described the characteristics, treatments and outcome of 75 IDH2 mutated patients both at diagnosis and relapse or refractory disease. Among the 33 relapsed/refractory AML patients with either IDH2^R140 or IDH2^R172, 28 (84.8%) patients received salvage therapy and 14 achieved a complete response (50%). Median duration of response was 15.2 months. Median, 1-y, 3-y and 5-y OS were 15.1 months (IQR, 4.6-37.7), 53.1% (95% CI, 33.2-69.5), 29.2% (95% CI, 12.6-48.1) and 24.4% (95% CI, 9.3-43.1), respectively. In responding patients, median OS was 37.7 months and 1-y, 3-y and 5-y OS was 85.7%, 57.1% and 47.6%, respectively. In non-responding patients, median OS was 5.0 months (IQR, 4.5-8.6) and 1-y and 3-y OS was 17.9% and 0%, respectively. Thus, a substantial number of R/R AML patients with IDH2 mutations can be salvaged by current treatments and benefit from prolonged survival. It is expected that novel targeted agents such as enasidenib will further improve efficacy and safety in the next future.