Dasatinib plus Peg-Interferon alpha 2b combination in newly diagnosed chronic phase chronic myeloid leukaemia: Results of a multicenter phase 2 study (DASA-PegIFN study)

Superior rates of deep molecular response (DMR) have been reported with the combination of tyrosine kinase inhibitors and pegylated-interferon-alpha (Peg-IFN) in patients with newly diagnosed chronic phase-chronic myeloid leukaemia (CP-CML). In this setting, this study investigated the efficacy and safety of dasatinib combined to Peg-IFN-α2b (Dasa-PegIFN, NCT01872442). A total of 79 patients (age ≤65 years) started dasatinib; 61 were eligible for Peg-IFNα-2b add-on therapy at month 3 for a maximum 21-months duration. Dasatinib was continued thereafter. The primary endpoint was the cumulative rate of molecular response 4.5 log (MR^4.5 ) by 12 months. The results are reported for the 5-year duration of the study. Grade 3 neutropenia was frequent with the combination but did not induce severe infection (one of grade 3). Other adverse events were generally low grade (4% of grade 3-4) and expected. Seventy-nine per cent and 61% of patients continued the Peg-IFN until months 12 and 24, respectively. Overall, at these time points, MR^4.5 rates were 25% and 38%, respectively. Thereafter, 32% and 46% of patients achieved a sustained (≥2 years) MR^4.5 or MR⁴ , respectively. This work established the feasibility and high rates of achievement of early and sustained DMR (a prerequisite for treatment-free-remission) with dasatinib and Peg-IFNα-2b combination as initial therapy.

COVID-19 systematic screening of asymptomatic haematopoietic stem cell donors: Less if often more

From COVID pandemic spread until now, many HSCT unrelated donor registries recommend as a precaution a systematic COVID-19 testing for all donors during the precollection time. Literature is quite poor to support this systematic attitude. We report one sibling allogeneic HSCT which we proceeded despite a positive COVID test on related asymptomatic donor and summarize the all seven cases reported until now. We suggest to question this systematic COVID testing, two years after pandemic began, when there is no systematic testing on other blood products received during all the haematological malignancies treatment process.

Real-world therapeutic response and tyrosine kinase inhibitor discontinuation in chronic phase-chronic myeloid leukemia: data from the French observatory

Guidelines for tyrosine kinase inhibitor (TKI)-treated chronic phase-chronic myeloid leukemia (CML) management are essentially based on data from clinical research trials; however, real-world data should be valuable for optimizing such recommendations. Here, we analyzed the data collected in the French CML Observatory database, a multicenter real-world cohort (n = 646), using a first-line "intention-to-treat" analysis strategy. This cohort included patients treated with first-line imatinib (n = 484), nilotinib (n = 103), dasatinib (n = 17), imatinib and interferon (n = 9), or second-generation (2G)-TKIs and interferon (n = 29). The cumulative incidence of major molecular response (MMR), MR4, MR4.5 and MR5 confirmed the faster response kinetics with 2G-TKIs. Multivariate analysis identified being a woman and residual disease at month 6 as the main predictive factors of deep molecular response (DMR). Moreover, 30% of patients met the criteria for treatment discontinuation (5 years of treatment and ≥ 2 years of DMR), but only 38% of them stopped treatment. Among the 92 patients who actually discontinued treatment due to optimal response, 31.5% relapsed (48% of them after > 6 months of TKI discontinuation). Multivariate analysis identified age and TKI duration as factors positively correlated with treatment-free remission maintenance. Late (> 6 months) relapses were more frequent in patients with the e14a2 BCR::ABL transcript. Relapse rate was higher in patients who stopped TKI before than after 5 years of treatment (52.6% vs 26%; p = 0.040). These results advocate caution concerning early treatment withdrawal, including in patients receiving 2G-TKIs. This still recruiting database is a valuable source of information for the real-world follow-up of patients with CML.

Efficiency of nilotinib to target chronic phase-chronic myeloid leukaemia primary mature CD34- and immature CD34+ cells

Accumulation in target cells is an essential pharmacokinetic step of targeted therapies. Tyrosine Kinase Inhibitors (TKI) against the BCR-ABL fusion protein in Chronic Phase-Chronic Myeloid Leukaemia (CP-CML) cells constitute a unique model in terms of efficacy, specificity, and in vivo demonstration of response heterogeneity by target cells. The overall therapeutic response to nilotinib is heterogeneous with no satisfactory explanation. To better understand the patients’ response heterogeneity, we quantified nilotinib uptake by primary CP-CML cells in standardized conditions using flow cytometry, which allowed also distinguishing mature (polymorphonuclear cells) from immature (CD34⁺) cells. Nilotinib was undetectable in 13.3% of PMN and 40% of CD34⁺ cells. Moreover, in CD34⁺ cells, intracellular nilotinib did not completely abolish BCR-ABL activity (monitored by CrkL phosphorylation inhibition), although nilotinib accumulated well in most CD34⁺ cell samples. Intracellular nilotinib concentration was inversely correlated with disease burden parameters, Sokal score, and early haematologic response at day 6 ± 1 only in PMN, suggesting an intrinsic ability to limit nilotinib entry in the forms with higher tumor cell burdenat diagnosis. These findings suggest that nilotinib accumulation in CP-CML cells is influenced by individual characteristics and intra-clonal heterogeneity, and might be used for pharmacokinetic studies and to assess the therapeutic response.

Poor prognosis of chromosome 7 clonal aberrations in Philadelphia-negative metaphases and relevance of potential underlying myelodysplastic features in chronic myeloid leukemia

Clonal chromosome abnormalities in Philadelphia-negative cells could concern chronic myeloid leukemia patients treated by tyrosine kinase inhibitors. The European LeukemiaNet distinguishes -7/del(7q) abnormalities as a “warning”. However, the impact of clonal chromosome abnormalities, and specifically those of -7/del(7q), in Philadelphia-negative cells on clinical outcomes is unclear and based on case-reports showing morphological dysplasia and increased risk of acute myeloid leukemia, suggesting the coexistence of chronic myeloid leukemia and high-risk myelodysplastic syndrome. The aim of this study was to determine whether the impact of -7/del(7q) clonal chromosome abnormalities in Philadelphia-negative cells on the clinical outcome is different from that of other types of abnormalities, and we argue for an underlying associated high-risk myelodysplastic syndrome. Among 102 chronic myeloid leukemia patients with clonal chromosome abnormalities in Philadelphia-negative cells with more than a median of 6 years of follow up, patients with -7/del(7q) more frequently had signs of dysplasia, a lower cumulative incidence of deep molecular response and often needed further treatment lines, with the consequent impact on event-free and progression-free survival. Morphological features of dysplasia are associated with myelodysplastic syndrome/acute myeloid leukemia mutations and compromise the optimal response to tyrosine kinase inhibitors, irrespectively of the type of clonal chromosome abnormalities in Philadelphia-negative cells. However, mutation patterns determined by next-generation sequencing could not clearly explain the underlying high-risk disease. We hereby confirm the pejorative prognostic value of -7/del(7q) clonal chromosome abnormalities in Philadelphia-negative cells and suggest that myelodysplastic features constitute a warning signal that response to tyrosine kinase inhibitors may be less than optimal.

[Second allogeneic hematopoietic stem cell transplant: Guidelines from the francophone Society of bone marrow transplantation and cellular therapy (SFGM-TC)]

Disease recurrence and graft dysfunction after allogeneic hematopoietic stem cell transplantation (allo-HSCT) currently remain among the major causes of treatment failure in malignant and non-malignant hematological diseases. A second allo-HSCT is a valuable therapeutic option to salvage those situations. During the 8th annual harmonization workshops of the french Society of bone marrow transplantation and cellular therapy (SFGM-TC), a designated working group reviewed the literature in order to elaborate unified guidelines on feasibility, indications, donor choice and conditioning in the case of a second allo-HSCT. In case of relapse, a second allo-HSCT with reduced intensity or non-myeloablative conditioning is a reasonable option, particularly in patients with a good performance status (Karnofsky/Lansky>80%), low co-morbidity score (EBMT score≤3), a longer remission duration after the first allo-HSCT (>6 months), and who present low disease burden at the time of second allo-HSCT. Matched related donors tend to be associated with better outcomes. In the presence of graft dysfunction (primary and secondary graft rejection), an immunoablative conditioning regimen is recommended. A donor change remains a valid option, especially in the absence of graft-versus-host disease after the first allo-HSCT.

Ponatinib evaluation and safety in real-life chronic myelogenous leukemia patients failing more than two tyrosine kinase inhibitors: the PEARL observational study

Ponatinib represents a remarkable progress in the treatment of heavily pretreated chronic myelogenous leukemia (CML) and de novo Philadelphia chromosome-positive ALL patients despite significant toxicity in clinical trials. To date, "real-life" data remain few and the use of ponatinib in this setting and its consequences remain mostly unknown. We report, within a national observational study, the use of ponatinib in unselected CML patients who had previously failed ≥2 lines of tyrosine kinase inhibitor (TKI) therapy (or one line if an Abelson (ABL)^T315I mutation was identified), in real-life conditions (2013-2014) in a compassionate program. Our analysis has been focused on 48 chronic phase CML patients recorded. With a median follow-up of 26.5 months since ponatinib initiation, the overall survival (OS) rates (80.5% at 3 years) and cumulative incidence of major molecular response (81.8% at 18 months) were similar to those of the phase II study, with no influence of BCR-ABL mutations nor the reason of ponatinib prescription. A specific subanalysis of the preexisting cardiovascular risk factors and events occurring on ponatinib is described. These events occurred after a median time on ponatinib of 5.8 months (excluding hypertension) and were observed in 29/48 patients (47%), even in those already on anti-aggregants/coagulants. The majority were not severe and resolved, but two cases were fatal. Other hematological or nonhematological nonvascular adverse events were similar to those previously described in trials. This observational study reports similar rates of survival, molecular responses, and a slight increase in the cardiovascular toxicity of ponatinib in real-life conditions, prompting improved control of cardiovascular risk factors and selection of patients.

DNA methylation profiling reveals a pathological signature that contributes to transcriptional defects of CD34+ CD15- cells in early chronic-phase chronic myeloid leukemia

Despite the high efficiency of tyrosine kinase inhibitors (TKI), some patients with chronic myeloid leukemia (CML) will display residual disease that can become resistant to treatment, indicating intraclonal heterogeneity in chronic‐phase CML (CP‐CML). To determine the basis of this heterogeneity, we conducted the first exhaustive characterization of the DNA methylation pattern of sorted CP‐CML CD34⁺CD15⁻ (immature) and CD34⁻CD15⁺ (mature) cells at diagnosis (prior to any treatment) and compared it to that of CD34⁺CD15⁻ and CD34⁻CD15⁺ cells isolated from healthy donors (HD). In both cell types, we identified several hundreds of differentially methylated regions (DMRs) showing DNA methylation changes between CP‐CML and HD samples, with only a subset of them in common between CD34⁺CD15⁻ and CD34⁻CD15⁺ cells. This suggested DNA methylation variability within the same CML clone. We also identified 70 genes that could be aberrantly repressed upon hypermethylation and 171 genes that could be aberrantly expressed upon hypomethylation of some of these DMRs in CP‐CML cells, among which 18 and 81, respectively, were in CP‐CML CD34⁺CD15⁻ cells only. We then validated the DNA methylation and expression defects of selected candidate genes. Specifically, we identified GAS2, a candidate oncogene, as a new example of gene the hypomethylation of which is associated with robust overexpression in CP‐CML cells. Altogether, we demonstrated that DNA methylation abnormalities exist at early stages of CML and can affect the transcriptional landscape of malignant cells. These observations could lead to the development of combination treatments with epigenetic drugs and TKI for CP‐CML.

Bone marrow hematons: An access point to the human hematopoietic niche

To understand the complex interactions between hematopoietic stem cells and the bone marrow niche, a human experimental model is needed. Our hypothesis is that hematons are an appropriate ex vivo model of human bone marrow. We analyzed the hierarchical hematopoietic cell content and the tissue organization of single hematons from healthy donors. Most (>90%) hematons contained precursors of all cell lineages, myeloid progenitors, and LTC-ICs without preferential commitment. Approximately, half of the hematons could generate significant levels of lympho-myeloid hematopoiesis after transplantation in an NSG mouse model, despite the low absolute numbers of transplanted CD34⁺ cells. Mesenchymal STRO-1⁺ and/or CD271⁺ cells formed a critical network that preserved hematon cohesion, and STRO-1⁺ cells colocalized with most hematopoietic CD34⁺ cells (68%). We observed an influence of age and gender. These structures represent a particularly attractive model for studying the homeostasis of the bone marrow niche and pathological changes that occur during diseases.

[Assessment and management of post-transplant iron overload: Guidelines of the Francophone Society of Marrow Transplantation and Cellular Therapy (SFGM-TC)]

To harmonize clinical practice in hematopoietic stem cell transplantation, the Francophone Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC) set up the sixth annual series of workshops which brought together practitioners from all member centers and took place in September 2015 in Lille. The main aim of this session was to describe the impact, evaluation and treatment of post-transplant iron overload.

Impact of ATG Dose on the Outcome of Patients Undergoing Reduced Intensity Conditioning Followed by Allogeneic Hematopoietic Stem Cell Transplantation for Hematological Malignancies

Reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation (allo-HSCT) is often proposed for patients with comorbidities. To enhance engraftment and limit graft-versus-host disease (GVHD), antithymoglobulin (ATG) is usually used. However, the dose needed remains unclear unlike myeloablative conditioning. In order to clarify this point, we conducted a retrospective study on patients who received a reduced intensity conditioning allo-HSCT based on a 2-day fludarabine and busulfan treatment with either 1 or 2 days of ATG treatment. One hundred and eight patients received 2.5 mg/kg (ATG2.5) and another 60 patients 5 mg/kg (ATG5). The median follow-up was 36 months. The median overall survival was 39 months and the median disease-free survival 45 months. In multivariate analysis, overall nonrelapse mortality (NRM) was independently influenced by the acute GVHD grade III-IV (p < 0.001) and ATG dose (30 vs. 21% for ATG5; p = 0.008). Despite heterogeneity of populations, using proportional-hazard assumptions, we have been able to observe in multivariate analysis a lower NRM in the ATG5 group. This leads to a statistically higher overall survival for the ATG5 group. In conclusion, 2 days of ATG decrease NRM independently without increasing the risk of relapse or infectious disease.

Autologous hematopoietic stem cell transplantation in elderly patients (≥ 70 years) with non-Hodgkin's lymphoma: A French Society of Bone Marrow Transplantation and Cellular Therapy retrospective study

INTRODUCTION

Limited data is available on the feasibility of high-dose chemotherapy followed by autologous hematopoietic stem cell transplantation (AHSCT) in elderly patients over 70 years of age with non-Hodgkin's lymphoma (NHL).

MATERIALS AND METHODS

In the setting of the Société Française de Greffe de Moelle et de Thérapie Cellulaire (SFGM-TC) group, we retrospectively analyzed 81 consecutive patients with NHL over 70 years of age who received AHSCT.

RESULTS

The median age at AHSCT was 72.3 years [70-80]. Patients' were diagnosed with diffuse large B-cell lymphoma (n=40), follicular lymphoma (n=16), mantle cell lymphoma (n=15), T-cell lymphoma (n=5), and other (n=5). Hematopoietic Cell Transplantation Comorbidity Index (HCT-CI) was 0 in 73% of patients. Main conditionings were BEAM (Carmustine-Etoposide-Cytarabine-Melphalan, n=61) and melphalan alone (n=14). Median delays to reach 0.5×10⁹/L neutrophils and 20 × 10(9)/L platelets were of 12 [9-76] days and 12 [0-143] days, respectively. One hundred day and one year cumulative incidence of NRM was 5.4% and 8.5%, respectively. The main cause of death remains relapse.

CONCLUSION

In conclusion, this study revealed that AHSCT seemed to be acceptable in patients over 70 years of age with NHL. Patient age is not a limiting factor if clinical condition is adequate.

Could enteral nutrition improve the outcome of patients with haematological malignancies undergoing allogeneic haematopoietic stem cell transplantation? A study protocol for a randomized controlled trial (the NEPHA study)

BACKGROUND

Myeloablative allogeneic haematopoietic stem cell transplantation (allo-HSCT) is a major procedure usually accompanied by multifactorial malnutrition, prompting the recommendation of systematic artificial nutritional support. Parenteral nutrition (PN) is usually administered during allo-HSCT, essentially for practical reasons. Recently published data suggest that enteral nutrition (EN), given as systematic artificial nutrition support, could decrease grade III-IV graft-versus-host disease (GVHD) and infectious events, which are associated with early toxicity after allo-HSCT and then have an impact on early transplant-related mortality (D100 mortality).

METHODS/DESIGN

We report on the NEPHA trial: an open-label, prospective, randomised, multi-centre study on two parallel groups, which has been designed to evaluate the effect of EN compared to PN on early toxicity after an allo-HSCT procedure. Two hundred forty patients treated with allo-HSCT for a haematological malignancy will be randomly assigned to two groups to receive either EN or PN. The primary endpoint will assess the effect of EN on D100 mortality. Secondary endpoints will compare EN and PN with regards to the main haematological, infectious and nutritional outcomes.

DISCUSSION

The impacts of nutritional support should exceed the limits of nutritional status improvement: EN may directly reduce immunological and infectious events, as well as decrease early transplant-related morbidity and mortality. EN and PN need to be prospectively compared in order to assess their impacts and to provide treatment guidelines. (Clinical trials gov number: NCT01955772; registration: July 19th, 2013).

Nilotinib and peginterferon alfa-2a for newly diagnosed chronic-phase chronic myeloid leukaemia (NiloPeg): a multicentre, non-randomised, open-label phase 2 study

BACKGROUND

Nilotinib is now recommended for patients with newly diagnosed chronic myeloid leukaemia in chronic phase and leads to important rates of molecular response 4·5 log (MR(4·5)), allowing the prospect of therapy cessation. However, most patients do not reach this criterion and nilotinib is taken for lengthy periods, resulting in chronic or late-onset adverse events. Nilotinib combined with interferon might further increase rates of MR(4·5), avoid late side-effects, and allow therapy cessation. In a phase 2 trial we aimed to assess the feasibility, safety, and deep molecular response of the combination of nilotinib (600 mg daily) and peginterferon alfa-2a in newly diagnosed patients with chronic-phase chronic myeloid leukaemia (CML).

METHODS

In a non-randomised, open-label, phase 2 trial, we enrolled adult patients (age ≥18 years) without any organ failure who had BCR-ABL-positive, chronic-phase CML, at diagnosis. After a priming procedure with 90 μg per week of peginterferon alfa-2a alone for a month, we gave patients peginterferon alfa-2a 45 μg per week combined with nilotinib 600 mg daily until 24 months after interferon initiation. The primary endpoint was the cumulative incidence of MR(4·5) at 12 months after initiation of peginterferon alfa-2a. Data were analysed by a modified intention-to-treat principle. This trial is registered at the European Clinical Trials Database (EudraCT), number 2010-019786-28.

FINDINGS

Between March 24, 2011, and Sept 27, 2011, we enrolled 42 patients. One patient withdrew consent before receiving any study treatment so was excluded from analysis; 41 patients received treatment with peginterferon alfa-2a and nilotinib. At 12 months, seven (17%) patients had achieved MR(4·5). Haematological and hepatic adverse events were frequent-with grade 3-4 neutropenias occurring in ten (24%) patients, grade 3-4 thrombocytopenias occurring in ten (24%) patients, grade 3-4 cholestatic events occurring in seven (17%) patients, and grade 3-4 elevations in aspartate aminotransferase or alanine aminotransferase occurring in three (7% patients-particularly during the first 3 months. However, 30 (73%) patients remained on interferon therapy at 1 year. Three grade 3-4 cardiac events (7% of patients, all coronary stenoses) occurred at later timepoints.

INTERPRETATION

The combination of peginterferon alfa-2a resulted in good molecular responses in patients. Despite substantial toxic effects, most patients remained on the study drugs for more than a year. This combination should now be tested in a randomised controlled trial.

FUNDING

Novartis Pharma.

Phosphorylation of spleen tyrosine kinase at tyrosine 348 (pSyk³⁴⁸) may be a marker of advanced phase of Chronic Myeloid Leukemia (CML)

We investigated Syk as a potential marker of CML progression. We observed a significant over-expression of Syk mRNA and constitutive phosphorylation of Syk Y348 in blast cells from six AP or BP-CML, but not in 15 CML in chronic phase. We could follow in vivo the recurrence of pSyk(348) throughout blast cell escape, despite observing storage of dasatinib in blast cells. A combination of dasatinib and R406 did not improve therapeutic efficacy in vitro. Our results strongly suggest that Syk activation could be a relevant biomarker of disease progression and dasatinib resistance but is probably not a molecular target.

Management of endocrino-metabolic dysfunctions after allogeneic hematopoietic stem cell transplantation

Allogeneic hematopoietic stem cell transplantation is mainly indicated in bone marrow dysfunction related to blood diseases, but also in some rare diseases (adrenoleucodystrophy, mitochondrial neurogastrointestinal encephalomyopathy or MNGIE…). After decades, this treatment has proven to be efficient at the cost of numerous early and delayed side effects such as infection, graft-versus-host disease, cardiovascular complications and secondary malignancies. These complications are mainly related to the conditioning, which requires a powerful chemotherapy associated to total body irradiation (myelo-ablation) or immunosuppression (non myelo-ablation). Among side effects, the endocrine complications may be classified as 1) hormonal endocrine deficiencies (particularly gonado- and somatotropic) related to delayed consequences of chemo- and above all radiotherapy, with their consequences on growth, puberty, bone and fertility); 2) auto-immune diseases, particularly dysthyroidism; 3) secondary tumors involving either endocrine glands (thyroid carcinoma) or dependent on hormonal status (breast cancer, meningioma), favored by immune dysregulation and radiotherapy; 4) metabolic complications, especially steroid-induced diabetes and dyslipidemia with their increased cardio-vascular risk. These complications are intricate. Moreover, hormone replacement therapy can modulate the cardio-vascular or the tumoral risk of patients, already increased by radiotherapy and chemotherapy, especially steroids and anthracyclins… Therefore, patients and families should be informed of these side effects and of the importance of a long-term follow-up requiring a multidisciplinary approach.

[Management of endocrine dysfunctions after allogeneic hematopoietic stem cell transplantation: a report of the SFGM-TC on gonadal failure and fertility]

In the attempt to harmonize clinical practices between different French transplantation centers, the French Society of Bone Marrow Transplantation and Cell Therapy (SFGM-TC) set up the third annual series of workshops which brought together practitioners from all member centers and took place in October 2012 in Lille. Here we report our results and recommendations regarding the management of short and long-term endocrine dysfunction following allogeneic stem cell transplantation. The key aim of this workshop was to give an overview gonadal failure, fertility preservation and post-transplant.

[Lymphoma and arteries: peri- or intravascular?]

PURPOSE

Lymphoma is a polymorphous disease that does not spare arteries. Arterial involvement may be perivascular or intravascular, with different prognostic and therapeutic implications.

PATIENTS AND METHODS

We present here one case of perivascular lymphoma and another case of intravascular lymphoma in order to highlight the specific features of each type.

RESULTS

The first patient was a woman who presented a pseudo-aneurysmal anterior iliac artery due to a non-Hodgkin lymphoma with subsequent bilateral pyelocalyceal distension. The second patient was a man who developed intravascular lymphomatosis expressed by an aneurysm of the common femoral then the primitive iliac artery.

CONCLUSION

The distinction between perivascular and intravascular arterial involvement is based on a range of features and is essential for an optimal care of patients with lymphoma.