Chronic Phase CML Research Articles

Combination of Nilotinib and Pegylated Interferon Alfa-2B Results in High Rates of MR4.5 at 24 Months - Primary Analysis of the ALLG CML 11 Pinnacle Study

Combination of Nilotinib and Pegylated Interferon Alfa-2B Results in High Rates of MR4.5 at 24 Months - Primary Analysis of the ALLG CML 11 Pinnacle Study

A Combination of CD302 gene Expression and 3-Months BCR-ABL1 Level Predicts Inferior Achievement of Deep Molecular Response in CP-CML Patients Treated with Imatinib

Introduction and Aim. Achievement of deep molecular response (DMR) is the prerequisite for treatment-free remission in chronic phase CML (CP-CML) patients (pts). Pts who fail to achieve early molecular response (BCR-ABL1 > 10% IS) at 3-months (mths), or have high ELTS score at diagnosis have inferior achievement of DMR. We and others have shown that the levels of NK-cell, T-cell, myeloid-derived suppressor cell, and neutrophils in the blood at diagnosis have an impact on DMR achievement. We hypothesized that Cluster of Differentiation (CD) (cell surface marker) gene expression might provide a surrogate marker to characterize immune cell composition. We aimed to identify pts who had a low probability of achieving DMR by 5 years (yrs) by combining 3-mths BCR-ABL1% and CD gene expression. This may enable clinicians to determine whether an individual patient is on a pathway towards DMR and potentially TFR or should be considered for a different therapeutic approach if TFR is the eventual goal. Methods. 119 blood samples from the imatinib-based TIDEL-II trial were subjected to transcriptomic microarray profiling. A total of 357 CD genes classified by the HUGO Gene Nomenclature Committee CD molecular gene group were assessed. We defined DMR as achieving MR4.5 (BCR-ABL1 < 0.0032%) at two consecutive time points. To construct a predictive model, the samples were randomly assigned to discovery and validation cohorts. Recursive partitioning and construction of a regression tree with tenfold cross-validation based on expression of 357 CD genes and 3-mths BCR-ABL1% were used as inputs in the discovery cohort. The performance was assessed based on accuracy of prediction of DMR by 5 yrs. The final model was validated using the independent validation cohort. All the analysis was performed using R statistical software. Results. Clinical variables (age, gender, ELTS, 3-mths BCR-ABL1%, MMR, and MR4.5) were well matched in the discovery (n=60) and independent validation cohort (n=59). The predictive model was constructed using the discovery cohort to reveal two risk groups: poor-risk (PR, 15% achieving MR4.5 at 5 yrs, n=19), and good-risk (GR, 88% achieving MR4.5 at 5 yrs, n=41) groups (Figure 1A-B). This model classified PR group by BCR-ABL1 ≥ 7.5% at 3 mths OR BCR-ABL1 < 7.5% at 3 months with high CD302 gene expression (≥7.9 log2 gene expression; top 15%) at diagnosis. GR group was defined as having both BCR-ABL1 < 7.5% and low CD302 gene expression (<7.9 log2 gene expression). These variables were chosen by the model based on accuracy performance in predicting DMR. CD302 is a C-type lectin receptor involved in cell adhesion and migration. It is expressed in myeloid populations as well as in blasts and leukemic stem cells (LSC) in AML. High expression of CD302 in PR pts may be a surrogate for increased LSC. The model was validated in the independent validation cohort. Pts identified as PR in the validation cohort had significantly lower 5-yrs MR4.5 achievement rate (14%, n=14) compared to those with GR (82%, n=45, p=0.0002, Figure 1C). We asked whether using the more conventional BCR-ABL1 10% cutoff instead of 7.5% in our model would give similar results, but the performance in predicting long-term DMR achievement was inferior: Pts predicted as PR with this criteria had ~2x higher achievement of DMR (e.g. 26% vs 14% using 3-mths BCR-ABL1 10% vs 7.5% cutoff respectively). ELTS score have been associated with the probability of DMR achievement. We compared the performance of ELTS in combination with 3-mths BCR-ABL1% by replacing CD302 gene expression with ELTS. The predictive accuracy was inferior. Pts with 3-mths BCR-ABL1 ≥7.5% OR BCR-ABL1 <7.5% with high/intermediate ELTS (PR-2) had about 3.3-3.5 fold higher DMR achievement rate than the PR group with CD302 in both discovery and validation cohorts (Figure 1D-E). In contrast, pts with 3-mths BCR-ABL1 <7.5% and low ELTS (GR-2) had approximately 1.1-1.2 fold lower DMR achievement rate than the GR group with CD302 in both discovery and validation cohorts (Figure 1D-E). Conclusion. We have constructed a predictive model for DMR achievement for pts who receive optimised frontline imatinib therapy. This model performs better than combining ELTS and 3-mths BCR-ABL1%. We postulate that this predictive model could enable identification of poor risk pts at 3 mths who would benefit from intensified therapeutic approaches to obtain eligibility for TFR and potentially optimal clinical outcome. Disclosures Yeung: Novartis: Honoraria, Research Funding; BMS: Honoraria, Research Funding; Pfizer: Honoraria; Amgen: Honoraria. Hughes:Novartis: Other: Advisory Board and Symposia, Research Funding; BMS: Research Funding.

A Phase I-II Study of Ruxolitinib (INCB18424) for Patients with Chronic Myeloid Leukemia with Minimal Residual Disease While on Therapy with Imatinib

A Phase I-II Study of Ruxolitinib (INCB18424) for Patients with Chronic Myeloid Leukemia with Minimal Residual Disease While on Therapy with Imatinib

Silent NK/T Cell Reactions Against Dasatinib during Sustained Deep Molecular Response before Discontinuation Are Associated with Longer Treatment-Free Remission: A Multicenter, Single-Arm, Phase 2 Study

Introduction Tyrosine kinase inhibitors (TKIs) markedly enhance the prognosis of chronic myelogenous leukemia (CML), potentially enabling the attainment of deep molecular response (DMR). Subsequently, the discontinuation of TKI became imperative to evade adverse events and financial burden of TKI therapy. In several studies, beginning with the STIM1 (Lancet Oncol 2010;11:1029), nearly 40%-60% of patients with chronic CML who sustained long DMR could discontinue TKI and attain long-term treatment-free remission (TFR). Remarkably, initial dasatinib specifically induces the elevation in lymphocytes, including large granular lymphocytes (LGL), NK cells, and cytotoxic T cells, as well as the decline in regulatory T cells (Tregs) in the early phase of treatment, related to early clinical responses.(Int J Hematol 2014;99:41) Nevertheless, lymphocyte variations by dasatinib during sustained DMR before cessation is an area of growing interest. In the Japanese multicenter prospective D-STOP trial (NCT01627132), we discontinued dasatinib following 2-year consolidation to sustain DMR in chronic CML to assess the TFR rate. We here present the final results of the D-STOP trial, including the peripheral NK/T cell change during dasatinib consolidation associated with successful TFR. Methods: Chronic phase CML patients treated with TKIs who had undetectable BCR-ABL1 mRNA were enrolled. After confirmation of undetectable BCR-ABL1 mRNA (International Scale <0.01%) using a real-time quantitative polymerase chain reaction (RQ-PCR) in the central laboratory, the patient received additional dasatinib treatment for another 2 years as consolidation therapy. Patients who maintained DMR during the consolidation therapy proceeded to discontinue dasatinib. BCR-ABL1 mRNA was monitored every month in year 1 and every 3 months in year 2. Molecular relapse was defined as two successive positive RQ-PCRs for BCR-ABL1 within 1 month. The relapsed patients restarted dasatinib treatment. The primary endpoint was treatment-free survival after 12 months of discontinuation. Lymphocyte subsets were analyzed using flow cytometry during and after the consolidation therapy. Results: Sixty-five patients received consolidation therapy, and 54 discontinued dasatinib treatment after maintenance of DMR for 2 years. Estimated treatment-free remission (TFR) rates at 12 and 36 months were 63.0% [95% confidence interval (CI): 48.7-74.3] and 59.3% (95% CI: 45.0-71.0), respectively.(Figure 1) CD3-CD56+NK, CD16+CD56+NK, CD57+CD56+NK large granular lymphocytes (NK-LGL), CD8+CD4- cytotoxic T, and CD57+CD3+T-LGL cell numbers were relatively elevated throughout 24-month consolidation only in failed patients who molecularly relapsed within 12 months. In successful patients (TFR >12-months), these subsets elevated transiently after 12 months but returned to basal levels after 24-month consolidation. (Figure 2)There were no differences in CD8-CD4+ helper T and Treg. cell numbers during consolidation between 2 groups. Therefore, smaller changes in the NK/T sebsets, particularly NK subset throughout consolidation, exhibited higher TFR rates. TFR rates of those exhibiting elevation in CD3-CD56+NK > 376 cells/mL, CD16+CD56+NK > 241 cells/mL,CD57+CD56+NK-LGL > 242 cells/mL or CD8+CD4- cytotoxic T cells > 212 cells/mL during consolidation compared with others were 26.7% (8.3%-49.6%) versus 78.3% (55.4%-90.3%), HR 0.032 (0.0027-0.38; P = 0.0064) (Figure 3), 31.2% (11.4%-53.6%) versus 85.0% (60.4%-94.9%), HR 0.039 (0.0031-0.48; P = 0.011), 36.8% (16.5%-57.5%) versus 77.3% (53.7%-89.8%), HR 0.21 (0.065-0.69; P = 0.010), or 41.2% (18.6%-62.6%) versus 76.5% (48.8%-84.9%), HR 0.18 (0.019-1.77; P = 0.14), respectively. Conclusion Silent responses of the T/NK subsets to dasatinib throughout consolidation was significant for longer TFR. Elevated NK/T, particularly NK lymphocytes responsive to dasatinib, could be immature cells with little immunosurveillance; their decline subsequently replaced by altered lymphocyte population with less response to dasatinib during sustained DMR might be immunologically significant. Disclosures Kumagai: Pfizer: Honoraria; Otsuka pharmacology: Honoraria; Novartis: Honoraria; Bristol-Myers Squibb: Honoraria. Nakaseko:Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria, Research Funding; Novartis: Honoraria. Nishiwaki:Novartis: Research Funding. Yoshida:Otsuka: Honoraria, Research Funding, Speakers Bureau; Bristol-Myers Squibb: Honoraria, Speakers Bureau; Pfizer: Honoraria, Speakers Bureau. Matsue:Janssen Pharmaceutical K.K.: Honoraria; Novartis Pharma K.K: Honoraria; Takeda Pharmaceutical Company Limited: Honoraria; Celgene: Honoraria; Ono Pharmaceutical: Honoraria. Morita:Bristol-Myers Squibb: Honoraria. Sakamoto,:Yakult Honsha Co. Ltd: Other: remuneration. Inokuchi:Bristol-Myers Squibb: Honoraria, Research Funding; Pfizer: Honoraria; Celgene: Honoraria; Novartis: Honoraria.

A Retrospective Analysis about Frequency of Monitoring in Italian Chronic Myeloid Leukemia Patients after Discontinuation

A Retrospective Analysis about Frequency of Monitoring in Italian Chronic Myeloid Leukemia Patients after Discontinuation

NUP98-HOXA9-Initiates Molecular and Biologic Features of Disease Progression in a Humanized Model of CML

Acute myeloid leukemias (AMLs) are heterogenous diseases often resulting from the acquisition of multiple genetic alterations that deregulate hematopoietic precursor proliferation and block normal differentiation. Chronic myeloid leukemia offers a unique opportunity to identify molecular mechanisms that interfere with normal differentiation in the context of a highly proliferative hematopoietic stem cell clone that produces massive number of functional differentiated myeloid cells due to the presence of a BCR-ABL1 fusion gene. Since the NUP98-HOXA9 (NA9) fusion gene has been identified in some CML blast crisis patients or de novo AML, we asked whether a humanized model of CML progression to AML would result from its lentiviral-mediated introduction into primary CML CD34+ cells from 3 chronic phase CML patients in which >97%, >96%, and 44% of the CD34+ longterm culture-initiating cells were Ph+/BCR-ABL1+. In vitro experiments showed the NA9-transduced cells produced a hugely increased number of granulo-monocytic progenitors in long-term cultures (up to 1000-fold, p=0.03; t-ratio test) and enhanced the serial replating activity of directly clonogenic cells as compared to matched samples of cells transduced with a control vector. In vivo experiments showed that 90% of sublethally irradiated NOD-SCID IL2Rgc-null mice expressing human IL3, GM-CSF and SCF constitutively that were transplanted with these same NA9-transduced cells developed evidence of a progressed myeloproliferative neoplasia. This included tissue infiltrates of eosinophils, basophils and mastocytes, exclusive myeloid differentiation and signs of an imminently fatal leukemia between 8 and 27 weeks post-transplant in 50% of cases, although an excess blast population was not seen in these. RNA-sequencing of cells analyzed just 48 hours after transduction revealed a signature of 53 genes that were more highly expressed in CD34+ CML cells carrying the NA9 fusion gene in comparison to control CML cells. This signature included many genes expressed by hematopoietic stem cells (HSCs), such as 5' HOXA genes, 3' HOXB genes, PBX3, MEIS1,ARID5B, AHR, REL, BMP6, GDF10, SFRP5, PPBP,PLA2G4A suggesting that NA9 induces the expression of a partial HSC program in later CML progenitor types that make up the bulk of the CD34+ CML population. Consistent with this hypothesis, the NA9 signature separated the HSCs, CMPs and GMPs of chronic CML patients as well as those of normal subjects (GSE47927; p=1x10-6, p=2x10-4 respectively). Most genes in the NA9 signature were also found to be over-expressed in CD34+ cells of patients in the accelerated phase and in the blast phase of CML, including ARID5B, AHR, STARD9, TOX, or FOXP1 (p=9.10-8; ANOVA) (GSE4170). The NA9 signature was also significantly enriched in transcripts of genes that are over-expressed in the blasts of AML patients carrying NPM1 mutations or MLL fusions and was predictive of overall survival in the AML cohort of the Cancer Genome Atlas (p=0.02; log-rank test, n=200). This stem cell signature was also associated with an increase in the number of H3K27ac marks (on average 7805 ± 960 peaks for NA9 vs 5888 ± 2739 peaks for control) at 48 hours post-transduction. De novo H3K27ac peaks in NA9+ CD34+ cells were located in proximal and distal enhancers of 993 genes (GREAT parameters TSS ± 2kb from TSS and 100kb max extension). These were significantly enriched genes in the GM-CSF signaling pathway (MySigDB, binomial p-value=2.19x10-8) and that are upregulated in granulocytes and monocytes following LPS exposure. H3K27ac peaks also matched with GATA1, RELA, MEF2A and IKZF1 transcription factor binding sites previously mapped by ChIPSeq experiments (adjusted p-value <0.05). Finally, we identified super-enhancers in 12 genes among which were PBX3, ANGPT1, MBNL1 and PRKACB. Overexpression of the NA9 fusion gene in chronic phase CD34+ CML cells thus appears to reprogram the expression of HSC genes as well as those associated with GM-CSF pathway activation and inflammatory responses via H3K27 acetylation of associated loci leading to a picture of advanced accelerated phase/disease progression but not the complete differentiation arrest seen in terminal blast crisis or frank AML. These findings highlight the multiplicity of biologically important molecular alterations that can result from a single epigenetic perturbation but, nevertheless, are insufficient to create an overt AML phenotype. Disclosures Turhan: novartis: Honoraria, Research Funding; Incyte: Consultancy, Honoraria.

A Report on 114 Patients Who Experienced Treatment Free Remission in a Single Institution during a 15 Years Period: Long Term Follow-up, Late Molecular Relapses and Second Attempts

Rousselot: Incyte: Research Funding; Pfizer: Research Funding. Cayuela:Incyte: Honoraria, Speakers Bureau; Novartis: Consultancy, Honoraria, Speakers Bureau.

Investigations on Novel Gene Variants Associated with Longterm Response to Tyrosine Kinase Inhibitors (TKIs) in Chronic Myeloid Leukemia: Implication in TKI-Cessation Clinical Trails

Introduction: Tyrosine kinase inhibitor (TKIs) have revolutionized CML treatment causing more than 80% patients to achieve durable cytogenetic and molecular remissions1. Initial CML treatment guidelines were to keep CML patients on TKIs for the life time2. Nevertheless, cost issues related to TKI-based treatment have given rise to thinking if TKI treatment can de safely discontinued in a subset of long-term treatment CML responders2. This led to carry out STOP-TKI trials in long-term TKI responders in CML globally1-3. Such efforts can culminate into significant reduction of costs related to very expensive TKI treatment that can spare billions of US dollars annually for treatment and research related to other hematological disorders1. One of the hindrance for successful application of STOP-TKI efforts is lack of any molecular and other biological biomarkers in CML patients with long-term response as potential candidates for treatment discontinuation3.As next generation sequencing (NGS) technology has proved to be very useful in elucidating novel biomarkers in hematological and other disorders, this study was designed to find novel genetic variants associated with long-term imatinib response in our CML patients. Materials and Methods: Selection of Study Subjects (N=123): 1.Chronic phase treatment-naïve CML patients (Control 1) 2.Chronic phase CML long-term TKI responders (at least 3 continuous years of MMR)2 (Experimental group) 3.CML patients with resistant to TKIs (Control 2) 4.CML patients in accelerated and blast crisis phases (Control 3) 5.Healthy controls All patients were recruited from Hayatabad Medical Complex, Peshawar, Pakistan. Sample Collection and DNA extraction:10 ml peripheral blood was collected from all study subjects. DNA was extracted at HOPES, University of the Punjab, Lahore, Pakistan. Patient follow-up was carried out during course of this study (2013-8). Whole Exome Sequencing (WES): WES was carried out using Illumina NGS instrument (HiSeq). bcl files were converted to fastq files by using bcl2fastqtool 4. Raw reads were aligned to genome using BWA tools while whole exome variants were annotated using Illumina Variant Studio 4. R package was employed to align specific gene mutants to disease phenotypes 5. Variants detected by WES were confirmed using Sanger sequencing. Results & Discussion: Novel genes/variants associated exclusively with long-term CML responders to imatinib and absent in all control groups are provided in Table 1. One gene of particular interest is RA1 gene that had multiple frameshift mutations, active throughout the body and controls functions of many genes involved in daily rhythms6. Our studies are supported by some previous studies that reported CML patients with some genotypes (rs460089-GC in SLC22A4 gene) showing stable major molecular response 7. Clinical Significance: Variants found in this study can serve as biomarkers of long term response that can help identify candidates of cessation of TKIs which is one of the major focus of many ongoing CML STOP-TKI trials.

270O - Imatinib induced toxicity and its influence on cytogenetic and molecular response in newly diagnosed patients with chronic myeloid leukemia

BackgroundIncidence of imatinib-induced toxicity and its influence on clinical outcomes in Indian patients with CML is not well-studied. We investigated the influence of imatinib-induced toxicity on therapeutic outcomes in newly diagnosed patients with CML. We also studied the effect of drug levels on imatinib-induced hematological toxicity. MethodsTwo hundred and fifty newly diagnosed patients with chronic-phase CML, started on imatinib therapy, were enrolled and followed-up for 24 months. Toxicity due to imatinib were assessed and graded as per CTCAE. Cytogenetic and molecular responses were assessed by conventional bone-marrow cytogenetics and qRTPCR using international scale, respectively, based on which patients were categorized as imatinib responders and non-responders. Imatinib trough levels were measured using LC-MS/MS. Multivariate analysis was done to find the influence of various covariates on imatinib response. ResultsA total of 719 adverse reactions due to imatinib occurred among 250 enrolled patients. Hematological toxicity was the most common imatinib-induced toxicity and its incidence was significantly higher in non-responders than responders (65% vs. 35%; P < 0.001). Patients with thrombocytopenia [RR = 1.768; 95%CI (1.357, 2.302); P < 0.001] and neutropenia [RR = 1.654; 95%CI (1.322, 2.070); P < 0.001] were at high risk of imatinib failure. Patients without any hematological toxicity were at lower risk for failure of imatinib therapy [RR = 0.520; 95%CI (0.388, 0.698); P < 0.001]. Although patients with hematological toxicity had higher imatinib levels than those without (2039.1±1361.6 vs. 1833.8±1335.3 ng/mL), the difference was not statistically significant [mean difference 205.2; 95% CI (590.4, -180); P = 0.295]. Hematological toxicity requiring dose interruption or reduction emerged as an independent factor predicting cytogenetic and molecular response to imatinib in multivariate analysis. ConclusionsImatinib induced hematological toxicities significantly influence cytogenetic and molecular response in patients with CML. Active monitoring and prompt management of imatinib induced adverse events is indispensable to achieve optimal therapeutic outcomes. Clinical trial identificationNot Applicable. Editorial acknowledgementNot Applicable. Legal entity responsible for the studyThe authors. FundingHas not received any funding. DisclosureAll authors have declared no conflicts of interest.

Complications of Tyrosine Kinase Inhibitors Therapy in Chronic Myeloid Leukemia - Chronic Phase

Chronic myeloid leukaemia is a malignant tumor of pluripotent haemopoetic stem cell, characterized by increase granulocytes with left shift and the presence of the Ph chromosome.Treatment of chronic phase is made with tyrosine kinase inhibitors administered orally and can have secondary effects: haematological and non-haematological. The purpose of this paper is to assess complications of tyrosine kinase inhibitor therapy in chronic phase of chronic myeloid leukemia and establishing correlations with the type of inhibitor used. The study was performed on a total of 140 patients diagnosed with chronic phase CML in the Hematology Department of the City Clinical Emergency Hospital Timisoara between January 2006 - January 2016. The lot proposed has been studied in terms of anthropometric parameters and also the haematological and biochemical. It showed complications after initiation of therapy with tyrosine kinase inhibitors and also the correlations statistically significant between complications and type of inhibitor used. The study reveals that regardless the type of inhibitor used both haematological complications arise and non haematological. The most common are: neutropenia, thrombocytopenia, anemia, fluid retention, muscle and joint pain. Less common are nausea, diarrhea, abdominal pain, increased liver enzymes. Despite complications of occurring, these modern therapies significantly improve both survival and quality of life of patients.

Case Presentations: Allograft or Third-Line Therapy in Very Resistant CML

Tyrosine kinase inhibitors (TKIs) are a remarkable therapy for chronic phase CML and the vast majority of patients respond to initial therapy. However, resistance does occur, and resistance is associated with a higher risk of progression to advanced phase. What does one do after initial TKI therapy has failed the patient? Another TKI? Allogeneic transplant? In this case presentation, we will consider a case which has demonstrated resistance to two lines of TKI therapy and offer the pros and cons of trying yet another TKI, versus moving to the potentially curative transplant option.

Expression Levels of JARID1B, Hes1 and MMP-9 Genes in CML Patients Treated with Imatinib Mesylate

To explore the relationship between the expression levels of JARID1B,Hes1 and MMP-9 genes and the stages of chronic myelogenous leukemia(CML) and the curative effect of imatinib mesylate (IM). Peripheral blood samples of 15 cases of CML in chronic phase and 10 cases of CML in progressive phase were collected from the Hematology Department of Taihe Hospital affiliated to Hubei University of Medicine and 15 cases of healthy people in the Physical Examination Center. CML patients were divided into effective group and ineffective group based on the efficacy after treatment with IM, then real-time PCR was used to detect the expression levels of JARID1B, Hes1 and MMP-9 mRNA, finally, the differences in the level of gene expression and their correlations with CML stages and IM curative efficacy were analysed. The expression levels of Hes1 and MMP-9 in initially diagnosed patients in chronic and progressive phase without IM treatment were significantly higher than those of health people（P＜0.05）. There was no significant difference in the expression level of JARID1B between chronic phase patients and health people（P＞0.05）, but the expression level of JARID1B in the progressive phase patients was higher than that of health people （P＜0.05）. The expression levels of JARID1B and Hes1 in the IM-effective group were not significantly different from those in the IM-ineffective group (P=0.85,P=0.82）, while the expression level of MMP-9 in the IM-effective group [JP2]was significantly lower than that in the IM-ineffective group（P＜0.05）. The expression levels of JARID1B Hes1 and MMP-9 relate with the different phase of CML; The expression levels of JARID1B and Hes1 have not significant relationship with IM curative efficacy, the MMP-9 gene expression level relates with IM curative efficacy.

Response to Comment on "PP2A inhibition sensitizes cancer stem cells to ABL tyrosine kinase inhibitors in BCR-ABL+ human leukemia".

LB100 sensitizes resistant chronic phase CML stem and progenitor cells to TKIs and spares healthy bone marrow cells.

Association of BCR/ABL transcript variants with different blood parameters and demographic features in Iraqi chronic myeloid leukemia patients.

BackgroundChronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by the presence of BCR‐ABL fusion gene (GenBank accession NC_000022.11). In the vast majority of CML patients, the typical subtype of BCR‐ABL transcript are b3a2, b2a2 or both. The aim of this study was to determine the different subtypes of BCR‐ABL transcript and their impact on the demographic and hematological parameters in Iraqi patients with CML.MethodsOne hundred patients with chronic phase CML (11 newly diagnosed and 89 imatinib‐resistant) were enrolled in this study. Ribonucleic acid (RNA) was extracted from leukocytes, and complementary DNA was created using reverse transcriptase polymerase chain reaction technique. A multiplex polymerase chain reaction with four specific primers was used to determine the BCR‐ABL fusion subtypes in each patient.ResultsMale to female ratio was 1.38:1. Fifty‐nine patients expressed b3a2 transcript, whereas 39 of the remaining cases were positive for b2a2 variant. One case expressed b2a3 transcript, while the last case coexpressed the two subtypes of mRNA b3a2/b2a2. Male and female were significantly associated with b3a2 and b2a2 subtypes, respectively. The b3a2 subtype showed higher total leukocyte count than b2a2 subgroup, while b2a2 variant demonstrated significantly elevated platelet counts compared to those with b3a2 transcript. A significantly higher plateletcrit percentage (PCT%) was found in patients with b2a2 transcript whereas.ConclusionsThe testified Iraqi group expressed M‐BCR‐ABL type with preponderance of b3a2 over b2a2 subtype. There was a gender‐skewed distribution in BCR‐ABL transcript types with b3a2 transcript more prevalent in males. The type of BCR‐ABL transcript is reflected by different leukocyte and platelet counts at diagnosis, which might represent a distinct phenotype and disease biology.

Comparative study of molecular response of first-line and second-line nilotinib in patients with chronic-phase chronic myelogenous leukemia

Comparative study of molecular response of first-line and second-line nilotinib in patients with chronic-phase chronic myelogenous leukemia

PF409 DURABILITY AND IMPACT ON QUALITY OF LIFE OF TREATMENT‐FREE REMISSION (TFR) IN PATIENTS WITH CHRONIC MYELOID LEUKEMIA (CML) AFTER STOPPING FRONTLINE (1L) NILOTINIB: ENESTFREEDOM 192‐WK RESULTS

Background:ENESTfreedom (NCT01784068) is a single‐arm, open‐label, phase 2 study evaluating TFR in patients with CML in chronic phase who achieved a sustained deep molecular response (DMR) with 1L nilotinib. In the primary analysis, 51.6% of patients remained in TFR 48 wks after stopping nilotinib. Analyses at 144 wks showed durability of TFR.Aims:To assess longer‐term maintenance and safety of TFR after 192 wks of follow‐up.Methods:Eligible patients had been treated with ≥2 y of 1L nilotinib and achieved MR4.5 (BCR‐ABL1 IS ≤0.0032%). After 1 y of consolidation treatment, patients with sustained DMR could attempt TFR. Nilotinib was resumed upon loss of major molecular response (MMR; BCR‐ABL1 IS ≤0.1%). As of 17 Sep 2018 (data cut‐off), all patients had either completed ≥192 wks of TFR, resumed nilotinib, or discontinued the study.Results:Of 190 patients who had entered TFR, 87 remained in TFR, 91 had resumed nilotinib and 12 had discontinued the study by the data cut‐off. At 192 wks, the TFR rate was 44.2% (84/190, 95% CI: 37.0–51.6%). Of patients in TFR at 144 wks, 5/89 were not evaluable for TFR at 192 wks as 2 had discontinued by 192 wks due to patient/physician decision, and 3 who were previously in MR4.5 did not have 192‐wk PCR data. A total of 90/91 (98.9%) and 84/91 (92.3%) patients who resumed nilotinib regained MMR and MR4.5, respectively. At 48 wks after regaining MMR or MR4.5, 75/90 and 73/84 patients, respectively, had stable responses. There were no disease progressions or deaths due to CML. A total of 10 deaths were reported in the 144‐wk analysis, with no new deaths reported subsequently. The treatment‐free survival rate at 192 wks was 48.7% (95% CI 41.4–55.6%; Figure). Rates of all‐grade AEs were 84.3% during consolidation and 77.5%, 70.8%, 48.3% and 52.8% during each subsequent 48‐wk period of TFR, respectively, among the 89 patients who remained in TFR for &gt;144 wks (including 87 patients for &gt;192 wks). Rates of musculoskeletal pain AEs (all‐grade) were 15.7% during consolidation, then increased during the first 48 wks of TFR (40.4%) and subsequently decreased during TFR to below levels seen during consolidation (9.0%, 3.4% and 3.4%, respectively). Rates of cardiovascular events were low across all periods (3.4%, 2.2%, 1.1%, 2.2% and 0%). Among the 91 patients who resumed nilotinib, the most common AEs were nasopharyngitis (18.7%) as well as pruritus, fatigue and increased lipase (14.3% each); the majority of AEs were grade 1/2. To further explore AEs that may affect quality of life, incidences of AEs grouped by category (rate &gt;10% on treatment) were analyzed during consolidation and the 1st, 2nd, 3rd, and 4th 48‐wk periods of TFR, respectively: gastrointestinal disorders, 29.2%, 28.1%, 16.9%, 6.7% and 3.4%; infections and infestations, 39.3%, 34.8%, 24.7%, 19.1% and 20.2%; musculoskeletal and connective tissue disorders: 27.0%, 50.6%, 22.5%, 7.9% and 10.1%; and general disorders and administration site conditions (eg, asthenia, pyrexia): 14.6%, 11.2%, 10.1%, 6.7% and 4.5%. In these AE categories, similar trends toward decreasing incidences during TFR compared with consolidation were observed.Summary/Conclusion:These results demonstrate the long‐term durability and safety of TFR following 1L nilotinib. There were no disease progressions or CML‐related deaths, and musculoskeletal pain AEs were transient. AEs that may adversely affect patients’ quality of life tended to decrease in frequency during TFR vs during consolidation. Patients should continue to be regularly monitored during TFR.image

PF411 ENESTOP 192‐WK RESULTS: DURABILITY AND IMPACT ON QUALITY OF LIFE OF TREATMENT‐FREE REMISSION (TFR) FOLLOWING SECOND‐LINE (2L) NILOTINIB (NIL) IN PATIENTS (PTS) WITH CHRONIC MYELOID LEUKEMIA (CML)

Background:The ENESTop study (NCT01698905) is evaluating TFR in pts with CML in chronic phase who achieved sustained deep molecular response with 2L NIL. In the primary analysis, 57.9% of pts remained in TFR 48 wks after stopping NIL. Analyses at 144 wks showed durability of TFR.Aims:To assess the maintenance and safety of TFR after a longer follow‐up of 192 wks.Methods:Eligible pts had received ≥3 y of treatment (including &gt;4 wks of imatinib followed by ≥2 y of NIL) and had achieved MR4.5 (BCR‐ABL1 IS ≤0.0032%) on NIL. Pts without confirmed loss of MR4.5 after 1 y of consolidation (CONS) treatment could attempt TFR. NIL was resumed upon loss of major molecular response (BCR‐ABL1 IS ≤0.1%) or confirmed loss of MR4 (BCR‐ABL1 IS ≤0.01%). By the data cut‐off (24 Sep 2018), all pts had either completed ≥192 wks of TFR, resumed NIL, or discontinued the study.Results:At the data cut‐off, of the 126 pts who entered TFR, 56 remained in TFR, 59 had resumed NIL and 11 had discontinued the study. At 192 wks, the TFR rate was 46.0% (58/126; 95% CI, 37.1–55.1%); all but 1 pt were in MR4.5. Of pts in TFR at 144 wks, only 1/61 had lost response (confirmed loss of MR4) by 192 wks; 2 other pts had discontinued due to pt/guardian decision and serious AE (polycythemia vera), respectively. Of pts who resumed NIL, 56/59 (94.9%) and 55/59 (93.2%) regained MR4 and MR4.5, respectively. Of 56 pts who regained MR4, 40 (71.4%) had stable MR4 96 wks later; the remaining 16 had either discontinued &lt;96 wks after regaining MR4 (n = 12) or were ongoing with &lt;96 wks after regaining MR4 (n = 4). Of 55 pts who regained MR4.5, 37 (67.3%) had stable MR4.5 96 wks later; the remaining 18 pts had either discontinued &lt;96 wks after regaining MR4.5 (n = 12) or were ongoing with &lt;96 wks after regaining MR4.5 (n = 6). There were no cases of disease progression or deaths due to CML. No new deaths have occurred since the 144‐wk analysis. The treatment‐free survival rate at 192 wks was 50.3% (95% CI, 41.2–58.7%; Figure). During CONS and the 1st, 2nd, 3rd and 4th 48‐wk periods of TFR, respectively, rates of all‐grade AEs were 80.6%, 85.5%, 67.7%, 51.6% and 56.5% among the 62 pts who remained in TFR for &gt;144 wks. Musculoskeletal pain AE rates increased during the first 48 wks of TFR (53.2%) vs CONS (11.3%), then decreased during each subsequent 48‐wk period of TFR to levels below that seen in CONS (21.0%, 14.5% and 3.2%, respectively). In pts who resumed NIL (n = 59), the most common AEs were hypertension (20.3%) and arthralgia (13.6%), with the majority of AEs being grade 1/2. The rates of frequently occurring (&gt;10% on treatment) additional AEs (grouped by category) that may affect quality of life were assessed during CONS and the subsequent 48‐wk periods of TFR to further explore the potential impact of TFR. During these study periods, respectively, incidences of these categories of AEs were: gastrointestinal disorders, 22.6%, 17.7%, 21.0%, 8.1% and 8.1%; infections and infestations, 35.5%, 37.1%, 21.0%, 17.7% and 16.1%; musculoskeletal and connective tissue disorders: 24.2%, 62.9%, 29.0%, 22.6% and 12.9%; general disorders and administration site conditions (eg, asthenia, pyrexia): 11.3%, 21.0%, 4.8%, 4.8% and 6.5%. Across these AE categories, incidences tended to decrease over time in TFR.Summary/Conclusion:These results demonstrate the long‐term durability and safety of TFR following 2L NIL. No disease progressions or CML‐related deaths were reported. Musculoskeletal pain AEs were transient and additional AEs that may impact quality of life tended to decrease in frequency during TFR.image

PB1940 LEVELS OF VASCULAR ENDOTHELIAL GROWTH FACTOR DURING TREATMENT OF CML PATIENTS WITH IMATINIB – A RETROSPECTIVE ANALYSIS

Background: Role of pro-angiogenic cytokine vascular endothelial growth factor (VEGF) in the course of chronic myelogenous leukemia (CML) and variations of its levels during treatment with interferon alfa and tyrosine kinase inhibitors (TKI) are being discussed in the literature reports. Aims: Aim of this study was to clarify a possibility to use the monitoring of VEGF levels for prognosis of the long-term progression-free survival of the patients with CML. Methods: Retrospective analysis of the VEGF levels at different time-points was performed in 47 patients with different kinds of response and duration of treatment with imatinib (400-800 mg daily) followed from 2000 to 2018 due to chronic phase CML. Treatment response was evaluated by karyotyping and quantitative real-time polymerase chain reaction (PCR). Serum level of VEGF was determined by immunoenzyme analysis using commercial Biosource kits. Results: All the patients were divided according to the duration of their CML treatment into the following groups. Group 1: 20 patients treated with imatinib mesylate (IM) frontline (3 patients) or as a second line therapy (17 patients) after interferon alfa. Median disease duration was 13 years (11-18). Complete cytogenetic response (CCyR) and major molecular response (MMR) was confirmed in 17 (85%) of the patients. After 10 years of IM treatment BCR-ABL was not detectable in 11 of the patients (64%), other 6 had MMR. Group 2: 10 patients treated with IM frontline. Median duration of CML was 8 years (7-10). All of the patients reached CCyR, in 7 of them MMR was detected (4 – MMR; 3 – BCR-ABL was undetectable). Group 3: 17 patients treated with IM administered after 2-3 lines of prior therapy. Among these patients 12 developed progression to the advanced disease stages by 5 years of treatment, the remaining members of this group were switched to nilotinib due to the lack or loss of response. They subsequently achieved cytogenetic and molecular response. Results of serum VEGF levels at different time-points during 60 months of IM treatment are summarized in Fig.1. The baseline parameters were comparable in all 3 groups. However starting from 1,5 months of treatment in patients of group 1 and 2 serum VEGF started reducing and in some cases with slight fluctuations remained comparable to the healthy individuals during all 60 months of therapy. In patients of the third group who either did not reach hematological and cytogenetic response or lost it during treatment serum VEGF level remained almost unchanged as compared to the baseline. The difference between VEGF values of groups 1,2 and group 3 was found to be significant at 3, 12, 48 and 60 months of IM treatment.Summary/Conclusion: We believe that monitoring of the VEGF serum levels during therapy with IM has 2 aspects. First of all rapid reduction of this cytokine during initial months of treatment may be a sign of high sensitivity of leukemic cells to the medication and optimal expected response which was confirmed in patients of groups 1 and 2 by karyotyping and PCR. Secondly patients with low levels of VEGF not achieving molecular response after 12 months of treatment but who continued IM therapy as the best available option reached optimal response after 24 months. Evaluation of VEGF levels as a marker of angiogenesis intensity in CML may be useful for patients who plan to stop treatment with IM as an addition to molecular monitoring of disease. Lack of reduction of VEGF levels in patients treated with IM in our opinion could be a negative prognostic factor.

PF403 NEGATIVE MR4.0 CHRONIC MYELOID LEUKEMIA AND ITS IMPLICATIONS FOR TREATMENT‐FREE REMISSION

Background:In the last few years, several clinical discontinuation trials have demonstrated that 40–60% of chronic phase CML patients (CP‐CML) who have achieved a stable deep molecular response, can stop therapy without relapsing. However, there is no consensus as to whether or not the depth of the molecular response is a prognostic factor for treatment‐free remission (TFR), which is reflected in the discrepancy between the various guidelines and opinions of experts in the field regarding the optimal molecular response required, MR4.0 or MR4.5, for a TFR attempt.Aims:In this work, we hypothesize that a discrepancy in the classification of the level of molecular response between laboratories involved in clinical trials could introduce a bias in the evaluation of the prognostic impact of treatment‐free remission (TFR).Methods:In an attempt to clarify this issue, we stratified by molecular response a cohort of 1087 CML patients and compared our results with those of 200 patients enrolled in the EURO‐SKI trial.Results:We found that none of the patients classified as MR4.0 had detectable disease (0/169) (Figure 1A). In addition, the frequency of undetectable disease negative cases increased to 29% (61/211) and 65% (149/230) in the MR4.5 and MR5.0 groups, respectively (Figure 1A). By contrast, the frequency of MR4.0 with undetectable disease in the EURO‐SKI trial was 72% (49/68), decreasing to 56% (48/85) and 58% (25/43) in the MR4.5 and MR5.0 groups, respectively (Figure 1B).Summary/Conclusion:Our results suggest that (1) There may be a bias in patient stratification by molecular response in the EURO‐SKI trial, making it impractical to attempt any association between molecular response depth and TFR success, (2) we should reassess the current classification of MR4.0 to include only patients with detectable disease and (3) the minimum quality criteria for scoring molecular response when disease is undetectable should be raised, with samples with &lt;32000 ABL1 or &lt;77000 GUSB transcripts be considered as unevaluable for classification of DMR.image

Ponatinib cost effective third-line option for chronic phase CML

Ponatinib cost effective third-line option for chronic phase CML