Impact of BCR::ABL1 single nucleotide variants on asciminib efficacy.

Asciminib is a potent and selective inhibitor of BCR::ABL1, with potential to avoid toxicity resulting from off-target kinase inhibition. Forty-nine patients treated with asciminib under a managed access program in the UK were evaluated for toxicity and response. Intolerance, rather than resistance (65% vs. 35%), was the most common reason for cessation of the last-line of treatment but asciminib was well tolerated, with most patients (29, 59%) remaining on treatment at a median of 14 months follow-up, and only 6 (12%) stopping for intolerance. Of 44 patients assessable for response, 29 (66%) achieved a complete cytogenetic response (CCyR) or better, with poorer responses seen in those stopping their last-line of therapy for resistance. Fewer patients with a prior history of a non-T315I-BCR::ABL1 single nucleotide variant (BSNV), or a non-T315I-BSNV detectable at baseline achieved CCyR. Serial tracking of BSNV by next generation sequencing demonstrated clonal expansion of BSNV-harbouring populations, which in some settings was associated with resistance (E459K, F317L, F359I), while in others was seen in the context of ongoing response, often with intensified dosing (T315I, I502F). These data suggest that asciminib exerts selective pressure on some BSNV-harbouring populations in vivo, some of which may respond to intensified dosing.

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.

How I Use Measurable Residual Disease in the Clinical Management of Adult Acute Lymphoblastic Leukemia.

Over the last decade the use of measurable residual disease (MRD) diagnostics in adult acute lymphoblastic leukemia (ALL) has expanded from a limited number of study groups in Europe and the United States to a world-wide application. In this review, we summarize the advantages and drawbacks of the current available techniques used for MRD monitoring. Through the use of three representative case studies, we highlight the advances in the use of MRD in clinical decision-making in the management of ALL in adults. We acknowledge discrepancies in MRD monitoring and treatment between different countries, reflecting differing availability, accessibility and affordability.

A novel mutation in exon 2 of FGB caused by c.221G>T † substitution, predicting the replacement of the native Arginine at position 74 with a Leucine (p.Arg74Leu † ) in a proband from a Kurdish family with dysfibrinogenaemia and familial venous and arterial thrombosis.

Dysfibrinogenaemias may present in either congenital or acquired form and are disorders of fibrinogen structure which may or may not be associated with abnormal function. More than 100 point mutations with single amino acid substitutions have been identified in over 400 families. These lead to defective DNA in the translated fibrinogen molecule. Such cases have improved our understanding of the fibrinogen-fibrin structure. Six members of a consanguineous family including a female proband, a female sibling, three male siblings and a daughter, with ages between 29 years and 53 years presented with early onset venous and premature arterial thromboembolic disease were investigated for a pro-thrombotic tendency associated with dysfibrinogenaemia. The family was investigated using standard coagulation assays and DNA sequencing of the genes encoding the FGA, FGB and FGG. All cases have dysfibrinogenaemia with a fibrinogen level 1.4 to 1.5 (1.9-4.3 g/L). Thrombophilia testing (including AT, PS & PC, F5 G1691A (FV Leiden)/F2 (prothombin G20210A) genotypes, homocysteine, antiphosphlipid antibody, paroxysmal nocturnal haemoglobinuria by flow cytometry and Janus Kinase-2 (exon 14)) were normal. PCR amplification and sequencing of exon 2 of FBG revealed a heterozygous mutation for a c.221G> T † substitution, predicting the replacement of the native Arginine at position 74 with a Leucine (p.Arg74Leu † ). In silico analysis of p.Arg74Leu strongly support pathogenicity. A novel mutation was identified in exon 2 of FGB caused by c.221G> T † substitution, predicting the replacement of Arginine at position 74 with a Leucine (p.Arg74Leu † ) in a proband from a Kurdish family with dysfibrinogenaemia and familial venous and arterial thrombosis.