Cardiovascular events in CML patients treated with Nilotinib: validation of the HFA-ICOS baseline risk score.

BACKGROUND: The therapeutic landscape of chronic myeloid leukaemia (CML) has been transformed by tyrosine kinase inhibitors (TKI). Nilotinib, showed higher rates of major molecular response than imatinib, however associated with higher cardiovascular (CV) toxicity. We sought to describe the CV events associated with nilotinib in a real-world population and assess the predictive value of the HFA-ICOS risk score. METHODS: The HFA-ICOS baseline risk was calculated for patients with CML treated with nilotinib beween 2006 and 2021. The primary end point was the incidence of all CV events. The secondary end point was the incidence of ischaemic events. Survival analysis evaluated the risk (hazard ratio [HR]) of events stratified by baseline risk category, whilst on nilotinib therapy. RESULTS: Two hundred and twenty-nine eligible patients were included. The incidence of CV events was 20.9% (95% CI: 15.7-26.2%) following a median duration of treatment of 34.4 months. The secondary end point occurred in 12.7% (95% CI: 8.4-16.9%) of the population. Patients with higher HFA-ICOS baseline score had higher rates of CV events (low: 11.2%, medium: 28.2% [HR: 2.51, 95% CI: 1.17-5.66], high/very high: 32.4% [HR: 3.57, 95% CI: 1.77-7.20]) and ischaemic events (low: 5.20%, medium: 17.9% [HR: 2.19, 95% CI: 0.97-4.96], high/very high: 21.6% [HR: 3.9, 95% CI: 1.91-7.89]). In patients who did not have a CV event, the median total dose at last follow up or cessation of nilotinib therapy was lower when compared to the total daily median dose of nilotinib in patients who had a CV event (450 mg vs. 600 mg, p = 0.0074). CONCLUSIONS: The HFA-ICOS risk stratification tool is an efficient discriminator at low, medium and high/very high risk of developing cardiovascular events, with an overall positive trend towards increasing cardiotoxicity rates with rising risk catergories. This study provides evidence to support the use of this predictive tool in nilotinib treated patients.

Effect of tyrosine kinase inhibitors on male fertility in patients with chronic phase chronic myeloid leukemia.

Advancements in the management of patients with chronic myeloid leukemia (CML) allowed them to achieve survival comparable with their healthy counterparts. Consequently, their care has widened with growing focus on quality of life, including parenting children. Although tyrosine kinase inhibitors (TKI) are contraindicated in pregnancy given their teratogenic effect, their effect on male fertility is less clear with contradictory results from animal studies and case reports/series. We compared the sperm analysis parameters, as the gold-standard assessment for male fertility, of 11 patients with CP- CML before and after TKI therapy. Median therapy duration was 5.1 years (range: 2.5-16.5). The sperm concentration, % progressive, and total motility before and after therapy were not significantly different (p = 0.376, 0.569, and 0.595, respectively). Our results suggest no impairment in fertility potential in male patients after TKI therapy. A larger sample size is crucial to support/refute our findings.

Treatment-free remission in CML patients with additional chromosome abnormalities in the Philadelphia-positive clone or variant Philadelphia translocations.

Probability of treatment-free remission (TFR) in CML patients with additional chromosomal abnormalities (ACA) in the Philadelphia-positive clone or variant Philadelphia translocations (ACA/Var-Ph group, blue panel), in those with no cytogenetic abnormality other than the classical Philadelphia translocation (c-Ph group, green panel) and in the subgroups of CML patients with high-risk ACA (HR-ACA, yellow panel) and Var-Ph (red panel).

Long-term outcomes after upfront second-generation tyrosine kinase inhibitors for chronic myeloid leukemia: managing intolerance and resistance.

Second-generation tyrosine kinase inhibitors (2GTKI) are more effective in inducing rapid molecular responses than imatinib when used first-line in patients with chronic myeloid leukemia in chronic phase (CML-CP). However, failure of first line-2GTKI (1L-2GTKI) still occurs and there is no consensus regarding subsequent management. We retrospectively analyzed the outcome of 106 CML-CP patients treated with 1L-2GTKI and with a median follow-up of 91 months. 45 patients (42.4%) switched to an alternative TKI, 28 for intolerance (26.4%) and 17 (16%) for resistance. Most patients who remained on 1L-2GTKI achieved deep molecular responses (DMR) and 15 (14.1%) are in treatment-free remission (TFR). Intolerant patients also obtained DMR, although most required multiple TKI changes and were slower to respond, particularly if treated with 2L-imatinib. Inferior outcomes were observed in resistant patients, who failed alternative 2L-2GTKI and required 3/4GTKI and/or allogeneic hematopoietic stem cell transplant (alloSCT). 7yr-OS was significantly lower for these individuals (66.1%) than for intolerant patients and those who remained on 1L-2GTKI (100% and 97.9%, respectively; p = 0.001). It is apparent that failure of 1L-2GTKI is a challenging problem in modern CML therapy. Intolerance can be effectively managed by switching to an alternative 2GTKI, but resistance requires early consideration of 3/4GTKI.

Tamoxifen for the treatment of myeloproliferative neoplasms: A Phase II clinical trial and exploratory analysis.

Current therapies for myeloproliferative neoplasms (MPNs) improve symptoms but have limited effect on tumor size. In preclinical studies, tamoxifen restored normal apoptosis in mutated hematopoietic stem/progenitor cells (HSPCs). TAMARIN Phase-II, multicenter, single-arm clinical trial assessed tamoxifen's safety and activity in patients with stable MPNs, no prior thrombotic events and mutated JAK2V617F, CALRins5 or CALRdel52 peripheral blood allele burden ≥20% (EudraCT 2015-005497-38). 38 patients were recruited over 112w and 32 completed 24w-treatment. The study's A'herns success criteria were met as the primary outcome ( ≥ 50% reduction in mutant allele burden at 24w) was observed in 3/38 patients. Secondary outcomes included ≥25% reduction at 24w (5/38), ≥50% reduction at 12w (0/38), thrombotic events (2/38), toxicities, hematological response, proportion of patients in each IWG-MRT response category and ELN response criteria. As exploratory outcomes, baseline analysis of HSPC transcriptome segregates responders and non-responders, suggesting a predictive signature. In responder HSPCs, longitudinal analysis shows high baseline expression of JAK-STAT signaling and oxidative phosphorylation genes, which are downregulated by tamoxifen. We further demonstrate in preclinical studies that in JAK2V617F+ cells, 4-hydroxytamoxifen inhibits mitochondrial complex-I, activates integrated stress response and decreases pathogenic JAK2-signaling. These results warrant further investigation of tamoxifen in MPN, with careful consideration of thrombotic risk.

FISH-negative BCR::ABL1-positive e19a2 chronic myeloid leukaemia: the most cryptic of insertions.

BACKGROUND: Chronic myeloid leukaemia (CML) is one of the most well characterised human malignancies. Most patients have a cytogenetically visible translocation between chromosomes 9 and 22 which generates the pathognomonic BCR::ABL1 fusion gene. The derivative chromosome 22 ('Philadelphia' or Ph chromosome) usually harbours the fusion gene encoding a constitutively active ABL1 kinase domain. A small subset of patients have no visible translocation. Historically, these 'Philadelphia chromosome negative' patients caused diagnostic confusion between CML and other myeloproliferative neoplasms; it is now well established that the BCR::ABL1 fusion gene can be generated via submicroscopic intrachromosomal insertion of ABL1 sequence into BCR, or, more rarely, of BCR into ABL1. The fusion genes arising from cryptic insertions are not detectable via G-banded chromosome analysis [karyotype] but can nevertheless always be detected using fluorescence in situ hybridisation (FISH) and/or qualitative reverse transcriptase PCR. CASE PRESENTATION: A 43-year-old female presented with suspected CML in 2007; however, contemporaneous gold standard laboratory investigations, G-banded chromosome analysis and FISH, were both negative. The reverse transcriptase quantitative PCR (RT-qPCR) assay available at the time, which was capable of detecting the common BCR::ABL1 transcripts (e13a2/e14a2), was also negative. Upon review in 2009, the newly recommended reverse transcriptase multiplex PCR (capable of detecting all BCR::ABL1 transcripts including the atypical ones) subsequently detected an e19a2 fusion. The patient then responded to tyrosine kinase inhibitor therapy. In contrast, FISH studies of both samples with three commercially available probes remained consistently negative. Retrospective whole genome sequencing, undertaken as part of the 100,000 Genomes Project, has now revealed that the patient's BCR::ABL1 fusion gene arose via a uniquely small insertion of 122 kb ABL1 sequences into BCR. CONCLUSIONS: We present a patient with suspected chronic myeloid leukaemia whose genetic investigations were originally negative at the time of diagnosis despite the use of contemporaneous gold standard methods. This is the first report of a FISH-negative, BCR::ABL1 positive CML which demonstrates that, even after sixty years of research into one of the most well understood human malignancies, whole genome sequencing can yield novel diagnostic findings in CML.

Cardiovascular risk in chronic myeloid leukaemia: A multidisciplinary consensus on screening and management.

INTRODUCTION: Tyrosine kinase inhibitors (TKIs) have become the mainstay of treatment for chronic myeloid leukaemia (CML), but cardiovascular (CV) risk and exacerbation of underlying risk factors associated with TKIs have become widely debated. Real-world evidence reveals little application of CV risk factor screening or continued monitoring within UK CML management. This consensus paper presents practical recommendations to assist healthcare professionals in conducting CV screening/comorbidity management for patients receiving TKIs. METHODS: We conducted a multidisciplinary panel meeting and two iterative surveys involving 10 CML specialists: five haematologists, two cardio-oncologists, one vascular surgeon, one haemato-oncology pharmacist and one specialist nurse practitioner. RESULTS: The panel recommended that patients commencing second-/third-generation TKIs undergo formal CV risk assessment at baseline, with additional investigations and involvement of cardiologists/vascular surgeons for those with high CV risk. During treatment, patients should undergo CV monitoring, with the nature and frequency of testing dependent on TKI and baseline CV risk. For patients who develop CV adverse events, decision-making around TKI interruption, cessation or change should be multidisciplinary and balance CV and haematological risk. CONCLUSION: The panel anticipates these recommendations will support healthcare professionals in implementing CV risk screening and monitoring, broadly and consistently, and thereby help optimise TKI treatment for CML.

Third primary SARS-CoV-2 mRNA vaccines enhance antibody responses in most patients with haematological malignancies.

SARS-CoV-2 infection, and resulting disease, COVID-19, has a high mortality amongst patients with haematological malignancies. Global vaccine rollouts have reduced hospitalisations and deaths, but vaccine efficacy in patients with haematological malignancies is known to be reduced. The UK-strategy offered a third, mRNA-based, vaccine as an extension to the primary course in these patients. The MARCH database is a retrospective observational study of serological responses in patients with blood disorders. Here we present data on 381 patients with haematological malignancies. By comparison with healthy controls, we report suboptimal responses following two primary vaccines, with significantly enhanced responses following the third primary dose. These responses however are heterogeneous and determined by haematological malignancy sub-type and therapy. We identify a group of patients with continued suboptimal vaccine responses who may benefit from additional doses, prophylactic extended half-life neutralising monoclonal therapies (nMAB) or prompt nMAB treatment in the event of SARS-CoV-2 infection.

Lymphoid blast crisis after prolonged treatment-free remission in chronic myeloid leukaemia after tyrosine kinase inhibitor de-escalation during the COVID-19 pandemic.

During the COVID-19 pandemic, access to health services has been considerably restricted and furthermore, patients have been reluctant to attend for routine monitoring, and this may have had a negative impact in the management of patients affected with haematological disorders. Sudden blast crisis in chronic myeloid leukaemia is categorized as a rapid onset of blastic phase, after a documented 'optimal' response to tyrosine kinase inhibitor (TKI) therapy and within 3 months of a normal complete blood count. Herein, we describe a case of patient who developed sudden blast crisis after TKI while in treatment-free remission.

Bosutinib versus imatinib for newly diagnosed chronic phase chronic myeloid leukemia: final results from the BFORE trial.

This analysis from the multicenter, open-label, phase 3 BFORE trial reports efficacy and safety of bosutinib in patients with newly diagnosed chronic phase (CP) chronic myeloid leukemia (CML) after five years' follow-up. Patients were randomized to 400-mg once-daily bosutinib (n = 268) or imatinib (n = 268; three untreated). At study completion, 59.7% of bosutinib- and 58.1% of imatinib-treated patients remained on study treatment. Median duration of treatment and time on study was 55 months in both groups. Cumulative major molecular response (MMR) rate by 5 years was higher with bosutinib versus imatinib (73.9% vs. 64.6%; odds ratio, 1.57 [95% CI, 1.08-2.28]), as were cumulative MR4 (58.2% vs. 48.1%; 1.50 [1.07-2.12]) and MR4.5 (47.4% vs. 36.6%; 1.57 [1.11-2.22]) rates. Superior MR with bosutinib versus imatinib was consistent across Sokal risk groups, with greatest benefit seen in patients with high risk. Treatment-emergent adverse events (TEAEs) were consistent with 12-month data. After 5 years of follow-up there was an increase in the incidence of cardiac, effusion, renal, and vascular TEAEs in bosutinib- and imatinib-treated patients, but overall, no new safety signals were identified. These final results support 400-mg once-daily bosutinib as standard-of-care in patients with newly diagnosed CP CML.This trial was registered at www.clinicaltrials.gov as #NCT02130557.

A retrospective observational research study to describe the real-world use of bosutinib in patients with chronic myeloid leukemia in the United Kingdom and the Netherlands.

OBJECTIVES: To describe the real-world effectiveness and safety of bosutinib in patients with chronic myeloid leukemia (CML). METHODS: This was a multi-center, retrospective, non-interventional chart review study conducted in 10 hospitals in the United Kingdom and the Netherlands. RESULTS: Eighty-seven patients were included. Bosutinib was the third-line tyrosine kinase inhibitor (TKI) in 33 (38%) and fourth-line in 44 (51%) patients. Median treatment duration was 15.6 months. Among 84 patients in chronic phase (CP) at baseline, 26 (31%) switched to bosutinib due to resistance and 57 (68%) due to intolerance to prior TKIs. Cumulative complete cytogenetic and major molecular response rates in CP patients were 67% and 55%, respectively. After a median follow-up of 21.5 months, nine (11%) patients in CP died; estimated overall survival rates at 1 and 2 years postbosutinib initiation were 95% and 91%, respectively. Overall, 33/87 (38%) patients discontinued bosutinib due to either lack of efficacy/disease progression (17%), adverse events (14%), death (2%), or other reasons (5%). Eighty-two (94%) patients experienced ≥1 adverse event possibly related to bosutinib, most commonly diarrhea (52%). CONCLUSIONS: Bosutinib used in routine clinical practice in heavily pretreated patients with CML is an effective treatment for patients in CP and is generally tolerable.

Assessment of quantitative polymerase chain reaction for BCR-ABL1 transcripts in chronic myeloid leukaemia: Are improved outcomes in patients with e14a2 transcripts an artefact of technology?

The clinical outcome of chronic myeloid leukaemia patients has vastly improved since the introduction of tyrosine kinase inhibitor treatment, with a significant proportion of patients able to achieve treatment-free remission. However, studies have shown that patients with the e13a2 transcript were less likely to achieve major molecular response compared to those with e14a2 transcripts. Most quantitative polymerase chain reaction (PCR) assays for detection of the BCR-ABL1 fusion gene do not differentiate between the two transcripts and we therefore hypothesised that technical bias linked to the qPCR assay could partially explain the discrepancy in outcomes. We designed an e14a2-specific assay and identified no difference in results compared to an e13a2 standard assay. We then demonstrated that the commercial e14a2 standards were causing a significant overestimation of the e13a2 transcripts. Finally, we reviewed patient management after the qPCR values were corrected, using our new evaluation. We concluded that despite statistically significant differences in qPCR results, there was no impact on patient management or outcome. We conclude that, at least in our institution, it would be inappropriate to perform separate assays for patients with e13a2 or e14a2.

Ponatinib with fludarabine, cytarabine, idarubicin, and granulocyte colony-stimulating factor chemotherapy for patients with blast-phase chronic myeloid leukaemia (MATCHPOINT): a single-arm, multicentre, phase 1/2 trial.

BACKGROUND: Outcomes for patients with blast-phase chronic myeloid leukaemia are poor. Long-term survival depends on reaching a second chronic phase, followed by allogeneic haematopoietic stem-cell transplantation (HSCT). We investigated whether the novel combination of the tyrosine-kinase inhibitor ponatinib with fludarabine, cytarabine, granulocyte colony-stimulating factor, and idarubicin (FLAG-IDA) could improve response and optimise allogeneic HSCT outcomes in patients with blast-phase chronic myeloid leukaemia. The aim was to identify a dose of ponatinib, which combined with FLAG-IDA, showed clinically meaningful activity and tolerability. METHODS: MATCHPOINT was a seamless, phase 1/2, multicentre trial done in eight UK Trials Acceleration Programme-funded centres. Eligible participants were adults (aged ≥16 years) with Philadelphia chromosome-positive or BCR-ABL1-positive blast-phase chronic myeloid leukaemia, suitable for intensive chemotherapy. Participants received up to two cycles of ponatinib with FLAG-IDA. Experimental doses of oral ponatinib (given from day 1 to day 28 of FLAG-IDA) were between 15 mg alternate days and 45 mg once daily and the starting dose was 30 mg once daily. Intravenous fludarabine (30 mg/m2 for 5 days), cytarabine (2 g/m2 for 5 days), and idarubicin (8 mg/m2 for 3 days), and subcutaneous granulocyte colony-stimulating factor (if used), were delivered according to local protocols. We used an innovative EffTox design to investigate the activity and tolerability of ponatinib-FLAG-IDA; the primary endpoints were the optimal ponatinib dose meeting prespecified thresholds of activity (inducement of second chronic phase defined as either haematological or minor cytogenetic response) and tolerability (dose-limiting toxicties). Analyses were planned on an intention-to-treat basis. MATCHPOINT was registered as an International Standard Randomised Controlled Trial, ISRCTN98986889, and has completed recruitment; the final results are presented. FINDINGS: Between March 19, 2015, and April 26, 2018, 17 patients (12 men, five women) were recruited, 16 of whom were evaluable for the coprimary outcomes. Median follow-up was 41 months (IQR 36-48). The EffTox model simultaneously considered clinical responses and dose-limiting toxicities, and determined the optimal ponatinib dose as 30 mg daily, combined with FLAG-IDA. 11 (69%) of 16 patients were in the second chronic phase after one cycle of treatment. Four (25%) patients had a dose-limiting toxicity (comprising cardiomyopathy and grade 4 increased alanine aminotransferase, cerebral venous sinus thrombosis, grade 3 increased amylase, and grade 4 increased alanine aminotransferase), fulfilling the criteria for clinically relevant activity and toxicity. 12 (71%) of 17 patients proceeded to allogeneic HSCT. The most common grade 3-4 non-haematological adverse events were lung infection (n=4 [24%]), fever (n=3 [18%]), and hypocalcaemia (n=3 [18%]). There were 12 serious adverse events in 11 (65%) patients. Three (18%) patients died due to treatment-related events (due to cardiomyopathy, pulmonary haemorrhage, and bone marrow aplasia). INTERPRETATION: Ponatinib-FLAG-IDA can induce second chronic phase in patients with blast-phase chronic myeloid leukaemia, representing an active salvage therapy to bridge to allogeneic HSCT. The number of treatment-related deaths is not in excess of what would be expected in this very high-risk group of patients receiving intensive chemotherapy. The efficient EffTox method is a model for investigating novel therapies in ultra-orphan cancers. FUNDING: Blood Cancer UK and Incyte.

Carfilzomib Enhances the Suppressive Effect of Ruxolitinib in Myelofibrosis.

As the first FDA-approved tyrosine kinase inhibitor for treatment of patients with myelofibrosis (MF), ruxolitinib improves clinical symptoms but does not lead to eradication of the disease or significant reduction of the mutated allele burden. The resistance of MF clones against the suppressive action of ruxolitinib may be due to intrinsic or extrinsic mechanisms leading to activity of additional pro-survival genes or signalling pathways that function independently of JAK2/STAT5. To identify alternative therapeutic targets, we applied a pooled-shRNA library targeting ~5000 genes to a JAK2V617F-positive cell line under a variety of conditions, including absence or presence of ruxolitinib and in the presence of a bone marrow microenvironment-like culture medium. We identified several proteasomal gene family members as essential to HEL cell survival. The importance of these genes was validated in MF cells using the proteasomal inhibitor carfilzomib, which also enhanced lethality in combination with ruxolitinib. We also showed that proteasome gene expression is reduced by ruxolitinib in MF CD34+ cells and that additional targeting of proteasomal activity by carfilzomib enhances the inhibitory action of ruxolitinib in vitro. Hence, this study suggests a potential role for proteasome inhibitors in combination with ruxolitinib for management of MF patients.

Fecal Microbiota Transplant Mitigates Adverse Outcomes Seen in Patients Colonized With Multidrug-Resistant Organisms Undergoing Allogeneic Hematopoietic Cell Transplantation.

The gut microbiome can be adversely affected by chemotherapy and antibiotics prior to hematopoietic cell transplantation (HCT). This affects graft success and increases susceptibility to multidrug-resistant organism (MDRO) colonization and infection. We performed an initial retrospective analysis of our use of fecal microbiota transplantation (FMT) from healthy donors as therapy for MDRO-colonized patients with hematological malignancy. FMT was performed on eight MDRO-colonized patients pre-HCT (FMT-MDRO group), and outcomes compared with 11 MDRO colonized HCT patients from the same period. At 12 months, survival was significantly higher in the FMT-MDRO group (70% versus 36% p = 0.044). Post-HCT, fewer FMT-MDRO patients required intensive care (0% versus 46%, P = 0.045) or experienced fever (0.29 versus 0.11 days, P = 0.027). Intestinal MDRO decolonization occurred in 25% of FMT-MDRO patients versus 11% non-FMT MDRO patients. Despite the significant differences and statistically comparable patient/transplant characteristics, as the sample size was small, a matched-pair analysis between both groups to non-MDRO colonized control cohorts (2:1 matching) was performed. At 12 months, the MDRO group who did not have an FMT had significantly lower survival (36.4% versus 61.9% respectively, p=0.012), and higher non relapse mortality (NRM; 60.2% versus 16.7% respectively, p=0.009) than their paired non-MDRO-colonized cohort. Conversely, there was no difference in survival (70% versus 43.4%, p=0.14) or NRM (12.5% versus 31.2% respectively, p=0.24) between the FMT-MDRO group and their paired non-MDRO cohort. Collectively, these data suggest that negative clinical outcomes, including mortality associated with MDRO colonization, may be ameliorated by pre-HCT FMT, even in the absence of intestinal MDRO decolonization. Further work is needed to explore this observed benefit.