Treatment Of Chronic Myeloid Leukemia Research Articles

Management of chronic myelogenous leukemia with COVID-19 and hepatitis B.

The application of immunosuppressive agents and targeted drugs has opened a novel approach for the treatment of hematological tumors, and the application of tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia is one of the landmark breakthroughs that has considerably improved the prognosis of CML patients. However, with the extensive use of TKI, the co-infection of CML patients has become increasingly apparent, especially regarding infectious diseases such as hepatitis B and COVID-19. The underlying mechanism may be related to the inhibition of the immune function by TKI. Poor management, including disease progression due to the infectious disease or TKI dose reduction or discontinuation, may lead to adverse clinical outcomes and can even be life-threatening. Therefore, this review principally provides an overview of the pathogenesis and standardized management principles of CML patients with comorbid COVID-19 or hepatitis B in order to improve clinicians' awareness of the risks so as to more effectively diagnose and treat CML and improve the survival rate and quality of life of patients. In the past two decades, owing to the advent of imatinib, chronic myeloid leukemia (CML) has transformed into a chronic controllable disease, and even treatment-free remission can be anticipated. Earlier studies have indicated that tyrosine kinase inhibitor (TKI) exerts a peculiar inhibitory effect on the body's immune function. Therefore, with the widespread application of TKI, more and more attention has been paid to the comorbidity of infectious diseases in CML patients, especially in patients with progressive disease or non-remission. Despite some studies revealing that the proportion and severity of SARS-CoV-2 infection in CML patients receiving TKI treatment are lower than in patients with other hematological malignancies, CML patients with stable disease are still recommended to be vaccinated against SARS-CoV-2, while TKI may or may not be discontinued. Meanwhile, the management of CML patients during the epidemic of coronavirus disease 2019 (COVID-19) still necessitates further discussion. This article also provides an overview of TKI-related hepatitis B reactivation. If not managed, patients may face adverse consequences such as hepatitis B reactivation-related hepatitis, liver failure, and progression of CML after forced withdrawal of medication. Therefore, this review aimed to comprehensively describe the management of CML patients with comorbid COVID-19, the pathogenesis of hepatitis B reactivation, the indicated population for prophylactic antiviral therapy, the time of antiviral drug discontinuation, and drug selection.

Asciminib in the Treatment of Philadelphia Chromosome-Positive Chronic Myeloid Leukemia: Focus on Patient Selection and Outcomes.

Tyrosine kinase inhibitors (TKIs) have significantly changed the treatment of chronic myeloid leukemia (CML) and improved outcomes for patients with CML in chronic phase (CML-CP) and accelerated phase (AP). Now armed with numerous effective therapeutic options, clinicians must consider various patient- and disease-specific factors when selecting the most appropriate TKI across lines of therapy. While most patients with CML expected to have a near-normal life expectancy due to the success of TKIs, emphasis has expanded beyond response and survival to include factors like quality of life, tolerability, and long-term toxicity management. Importantly, a subset of patients can achieve sustained deep molecular response and can attain treatment-free remission. Despite these successes, unmet needs remain related to CML treatment, including the persistent challenge of treatment resistance and intolerance, broadening treatment options for patients with resistance mutations or serious comorbidities, and focus on specific populations such as children and young adults. In particular, the only previously available treatments for patients with CML-CP with the T315I mutation were ponatinib, olverembatinib (exclusively approved for use in China at the time of this writing), omacetaxine, and hematopoietic stem cell transplantation. Asciminib has entered the CML treatment landscape as a new option for adult patients with CML-CP who have received ≥2 prior TKIs or those with the T315I mutation. Asciminib's unique mechanism of action, Specifically Targeting the ABL Myristoyl Pocket, sets it apart from traditional adenosine triphosphate-competitive TKIs. While asciminib may overcome unmet needs for patients with CML-CP and continues to be studied in other novel settings, guidance on how to integrate asciminib in treatment algorithms is needed. This review focuses on clinical data and how asciminib can overcome current unmet needs, discusses how to individualize patient selection, and highlights future directions to investigate asciminib in earlier lines of therapy and in children and adolescents.

Radotinib Decreases Prion Propagation and Prolongs Survival Times in Models of Prion Disease.

The conversion of cellular prion protein (PrPC) into pathogenic prion isoforms (PrPSc) and the mutation of PRNP are definite causes of prion diseases. Unfortunately, without exception, prion diseases are untreatable and fatal neurodegenerative disorders; therefore, one area of research focuses on identifying medicines that can delay the progression of these diseases. According to the concept of drug repositioning, we investigated the efficacy of the c-Abl tyrosine kinase inhibitor radotinib, which is a drug that is approved for the treatment of chronic myeloid leukemia, in the treatment of disease progression in prion models, including prion-infected cell models, Tga20 and hamster cerebellar slice culture models, and 263K scrapie-infected hamster models. Radotinib inhibited PrPSc deposition in neuronal ZW13-2 cells that were infected with the 22L or 139A scrapie strains and in cerebellar slice cultures that were infected with the 22L or 263K scrapie strains. Interestingly, hamsters that were intraperitoneally injected with the 263K scrapie strain and intragastrically treated with radotinib (100 mg/kg) exhibited prolonged survival times (159 ± 28.6 days) compared to nontreated hamsters (135 ± 9.9 days) as well as reduced PrPSc deposition and ameliorated pathology. However, intraperitoneal injection of radotinib exerted a smaller effect on the survival rate of the hamsters. Additionally, we found that different concentrations of radotinib (60, 100, and 200 mg/kg) had similar effects on survival time, but this effect was not observed after treatment with a low dose (30 mg/kg) of radotinib. Interestingly, when radotinib was administered 4 or 8 weeks after prion inoculation, the treated hamsters survived longer than the vehicle-treated hamsters. Additionally, a pharmacokinetic assay revealed that radotinib effectively crossed the blood-brain barrier. Based on our findings, we suggest that radotinib is a new candidate anti-prion drug that could possibly be used to treat prion diseases and promote the remission of symptoms.

Despite warnings, co-medication with proton pump inhibitors and dasatinib is common in chronic myeloid leukemia, but XS004, a novel oral dasatinib formulation, provides reduced pH-dependence, minimizing undesirable drug-drug interactions.

Dasatinib and other tyrosine kinase inhibitors (TKI) have revolutionized the treatment of chronic myeloid leukemia (CML). However, as a lipophilic weak base, crystalline monohydrate, dasatinib (Sprycel®) is poorly soluble, rendering a pH-dependent absorption and a highly variable bioavailability. Thus, co-medication with proton pump inhibitors (PPI) profoundly impairs dasatinib uptake and is clearly recommended against. XS004 is a novel oral immediate release and amorphous solid dispersion (ASD) formulation of dasatinib and is bioequivalent to the original crystalline dasatinib at 30% lower dosages. XS004 is designed to mitigate gastric pH dependency, thus optimizing absorption and bioavailability. We investigated the prevalence of dasatinib and PPI co-medication among chronic-phase CML patients in a real-world setting and assessed the plasma pharmacokinetics (PK) of XS004 with and without PPI co-medication (omeprazole) in healthy volunteers. Using the Swedish CML and Prescribed Drug Registers, we identified 676 TKI-treated CML patients; 320 (47%) had been prescribed PPI at some point after CML diagnosis. Among dasatinib-treated patients, the 2-year cumulative PPI co-medication was 24%. Interestingly, the 5-year overall survival was significantly lower for TKI-treated CML patients with versus without PPI co-medication (79% vs. 94%; hazard ratio 3.5; 95% confidence interval, 2.1-5.3; p < .0001). When assessing PK of XS004, neither Cmax nor area under the plasma concentration curve levels in plasma were significantly altered by the PPI co-medication. In conclusion, despite warnings, PPI co-medication is common among dasatinib-treated CML patients in a real-world setting. The new XS004 ASD formulation of dasatinib provided, in contrast to original crystalline dasatinib, superior pH independence with stable bioavailability, thereby minimizing drug-drug interactions. This may improve the long-term efficacy and tolerability of dasatinib in CML.

Mitochondrial Dysfunction in Cardiotoxicity Induced by BCR-ABL1 Tyrosine Kinase Inhibitors -Underlying Mechanisms, Detection, Potential Therapies.

The advent of BCR-ABL tyrosine kinase inhibitors (TKIs) targeted therapy revolutionized the treatment of chronic myeloid leukemia (CML) patients. Mitochondria are the key organelles for the maintenance of myocardial tissue homeostasis. However, cardiotoxicity associated with BCR-ABL1 TKIs can directly or indirectly cause mitochondrial damage and dysfunction, playing a pivotal role in cardiomyocytes homeostatic system and putting the cancer survivors at higher risk. In this review, we summarize the cardiotoxicity caused by BCR-ABL1 TKIs and the underlying mechanisms, which contribute dominantly to the damage of mitochondrial structure and dysfunction: endoplasmic reticulum (ER) stress, mitochondrial stress, damage of myocardial cell mitochondrial respiratory chain, increased production of mitochondrial reactive oxygen species (ROS), and other kinases and other potential mechanisms of cardiotoxicity induced by BCR-ABL1 TKIs. Furthermore, detection and management of BCR-ABL1 TKIs will promote our rational use, and cardioprotection strategies based on mitochondria will improve our understanding of the cardiotoxicity from a mitochondrial perspective. Ultimately, we hope shed light on clinical decision-making. By integrate and learn from both research and practice, we will endeavor to minimize the mitochondria-mediated cardiotoxicity and reduce the adverse sequelae associated with BCR-ABL1 TKIs.

Summary of Tyrosine Kinase STI-571 in the Treatment of Chronic Myeloid Leukemia

Chronic Myeloid Leukemia (CML) is a hematological malignancy characterized by the presence of the Philadelphia chromosome, which results in the formation of the BCR-ABL fusion protein with constitutive tyrosine kinase activity. The discovery and development of targeted therapies, such as the tyrosine kinase inhibitor STI-571 (Imatinib), revolutionized the treatment of CML by specifically inhibiting the BCR-ABL kinase activity. This abstract provides a summary of the therapeutic efficacy and clinical impact of STI-571 in the management of CML.Sti-571, a specific tyrosine kinase inhibitor, is a novel antitumor drug that has entered clinical trials and can effectively treat chronic myeloid leukemia caused by abnormal proliferation of hematopoietic stem cells. In this paper, the mechanism of action and regulation of cell cycle of this drug were summarized, and the problems of drug resistance were explored in depth and the development prospects of this drug were briefly introduced. The introduction of STI-571 has dramatically changed the management of CML, leading to a paradigm shift from conventional chemotherapy and allogeneic stem cell transplantation as the primary treatment options. The drug has shown superior efficacy compared to interferon-alpha therapy, the standard treatment before its introduction. STI-571 is generally well-tolerated, with fewer severe adverse effects, making it an attractive option for long-term therapy. Resistance to STI-571 has been observed in a subset of patients, primarily due to the emergence of BCR-ABL kinase domain mutations. However, the development of second-generation tyrosine kinase inhibitors, such as dasatinib and nilotinib, has provided alternative treatment options for patients who fail to respond to or develop resistance to STI-571.

Discovery of 3-((3-amino-1H-indazol-4-yl)ethynyl)-N-(4-((4-ethylpiperazin-1-yl)methyl)-3-(trifluoromethyl)phenyl)benzamide (AKE-72), a potent Pan-BCR-ABL inhibitor including the T315I gatekeeper resistant mutant

BCR-ABL inhibition is an effective therapeutic approach for the treatment of chronic myeloid leukaemia (CML). Herein, we report the discovery of AKE-72 (5), a diarylamide 3-aminoindazole, as a potent pan-BCR-ABL inhibitor, including the imatinib-resistant mutant T315I. A focussed array of compounds 4a, 4b, and 5 has been designed based on our previously reported indazole I to improve its BCR-ABLT315I inhibitory activity. Replacing the morpholine moiety of I with the privileged tail (4-ethylpiperazin-1-yl)methyl afforded 5 (AKE-72) with IC50 values of < 0.5 nM, and 9 nM against BCR-ABLWT and BCR-ABLT315I, respectively. Moreover, AKE-72 potently inhibited a panel of other clinically important mutants in single-digit nanomolar IC50 values. AKE-72 elicited remarkable anti-leukemic activity against K-562 cell line (GI50 < 10 nM, TGI = 154 nM). In addition, AKE-72 strongly inhibited the proliferation of Ba/F3 cells expressing native BCR-ABL or its T315I mutant. Overall, AKE-72 may serve as a promising candidate for the treatment of CML, including those harbouring T315I mutation.

Key principles of drug therapy in patients with chronic myeloid leukemia

Objective: to summarize scientific information about the basic principles of modern drug therapy for patients with chronic myeloid leukemia (CML) considering their individual characteristics.Material and methods. The basis of the study included modern scientific articles and clinical guidelines on CML diagnosis and treatment (2021), State Register of Medicines (SRM) of the Russian Federation, instructions for the use of medicines. The following methods were used: structural analysis, analytical method, content analysis, retrospective analysis, systematic approach, situational-logical and graphical methods of analysis.Results. The analysis made it possible to summarize scientific information about the basic principles of drug therapy for patients suffering from CML. It was revealed that the problem of CML therapy today is relevant, since every year there is an increase in the incidence of this nosology. Currently, the most significant is the prescription of tyrosine kinase inhibitors (TKIs), since they have pronounced effects and are well tolerated by patients. Therapy for CML in TKIs prescription consists of several lines. Imatinib is the first line therapy because it has better safety profile. There are combinations with imatinib; for example, it is used together with interferon alfa, which allows, in some cases, to increase the response to treatment. The following drugs are used in the second line: nilotinib, dasatinib, bosutinib, ponatinib. If TKI therapy is ineffective, it is possible to prescribe standard chemotherapy, interferon therapy, or bone marrow transplantation in the absence of contraindications. Studies are underway on the possibility of using and including in clinical guidelines such drugs as arsenic trioxide, decitabine, omacetaxime, inhibitors of farnesyl transferases, granulocyte-macrophage factors, antitumor vaccines. The analysis of SRM identified 27 trade names for TKIs, the share of domestic drugs was 60%. There were no Russian analogues for bosutinib and ponatinib in SRM, which are recommended for use in case of ineffective TKI therapy of previous lines.Conclusion. The study of drug provision for CML patients is an urgent task for pharmaceutical practice and for the healthcare system as a whole. Currently, the acute issues are the individual approach to the treatment of each CML patient considering concomitant diseases, and the search for new, more effective drugs that can increase the life expectancy and quality of life of patients suffering from this disease.

Histone demethylase PHF8 facilitates the development of chronic myeloid leukaemia by directly targeting BCR::ABL1.

Although tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of chronic myeloid leukaemia (CML), TKI resistance remains a major challenge. Here, we demonstrated that plant homeodomain finger protein 8 (PHF8), a histone demethylase was aberrantly enriched in CML samples compared to healthy controls. PHF8 inhibited CML cell differentiation and promoted CML cell proliferation. Furthermore, the proliferation-inhibited function of PHF8-knockdown have stronger effect on imatinib mesylate (IM)-resistant CML cells. Mechanistically, we identified that PHF8 as a transcriptional modulator interacted with the promoter of the BCR::ABL1 fusion gene and alters the methylation levels of H3K9me1, H3K9me2 and H3K27me1, thereby promoting BCR::ABL1 transcription. Overall, our study suggests that targeting PHF8, which directly regulates BCR::ABL1 expression, is a useful therapeutic approach for CML.

Pharmacological assessment of the antineoplastic and immunomodulatory properties of a new spiroindolone derivative (7',8'-Dimethoxy-1',3'-dimethyl-1,2,3',4'-tetrahydrospiro[indole-3,5'-pyrazolo[3,4-c]isoquinolin]-2-one) in chronic myeloid leukemia.

The discovery and development of effective novel compounds is paramount in oncology for improving cancer therapy. In this study, we developed a new derivative of spiroindolone (7',8'-Dimethoxy-1',3'-dimethyl-1,2,3',4'-tetrahydrospiro[indole-3,5'- pyrazolo[3,4-c]isoquinolin]-2-one) and evaluated its anticancer- and immunomodulatory potential in a vitro model of chronic leukemia. We utilized the chronic leukemia cell line K562, as well as non-cancerous peripheral blood mononuclear cells (PBMC) and Vero cells (kidney epithelium of Cercopithecus aethiops). We assessed the cytotoxicity of the compound using the MTT assay, and performed cell cycle assays to determine its impact on different stages of the cell cycle. To evaluate its antineoplastic activity, we conducted a colony formation test to measure the effect of the compound on the clonal growth of cancer cells. Furthermore, we evaluated the immunomodulatory activity of the compound by measuring the levels of pro and anti-inflammatory cytokines. The study findings demonstrate that the spiroindolone-derived compound exerted noteworthy cytotoxic effects against K562 cells, with an IC50 value of 25.27µg/mL. Additionally, it was observed that the compound inhibited the clonal proliferation of K562 cells while displaying minimal toxicity to normal cells. The compound exhibited its antiproliferative activity by inducing G2/M cell cycle arrest, preventing the entry of K562 cells into mitosis. Notably, the compound demonstrated an immunomodulatory effect by upregulating the production of cytokines IL-6 and IL-12/23p40. In conclusion, the spiroindolone-derived compound evaluated in this study has demonstrated significant potential as a therapeutic agent for the treatment of chronic myeloid leukemia. Further investigations are warranted to explore its clinical applications.

Chloroquine Intervenes Nephrotoxicity of Nilotinib through Deubiquitinase USP13-Mediated Stabilization of Bcl-XL.

Nephrotoxicity has become prominent due to the increase in the clinical use of nilotinib, a second-generation BCR-ABL1 inhibitor in the first-line treatment of Philadelphia chromosome-positive chronic myeloid leukemia. To date, the mechanism of nilotinib nephrotoxicity is still unknown, leading to a lack of clinical intervention strategies. Here, it is found that nilotinib could induce glomerular atrophy, renal tubular degeneration, and kidney fibrosis in an animal model. Mechanistically, nilotinib induces intrinsic apoptosis by specifically reducing the level of BCL2 like 1 (Bcl-XL) in both vascular endothelial cells and renal tubular epithelial cells, as well as in vivo. It is confirmed that chloroquine (CQ) intervenes with nilotinib-induced apoptosis and improves mitochondrial integrity, reactive oxygen species accumulation, and DNA damage by reversing the decreased Bcl-XL. The intervention effect is dependent on the alleviation of the nilotinib-induced reduction in ubiquitin specific peptidase 13 (USP13) and does not rely on autophagy inhibition. Additionally, it is found that USP13 abrogates cell apoptosis by preventing excessive ubiquitin-proteasome degradation of Bcl-XL. In conclusion, the research reveals the molecular mechanism of nilotinib's nephrotoxicity, highlighting USP13 as an important regulator of Bcl-XL stability in determining cell fate, and provides CQ analogs as a clinical intervention strategy for nilotinib's nephrotoxicity.

Control of Ph+ and additional chromosomal abnormalities in chronic myeloid leukemia by tyrosine kinase inhibitors.

Chronic myeloid leukemia (CML) is a type of blood cancer that is known to affect hematopoietic stem cells. The presence of the Philadelphia chromosome (Ph+) is the major characteristic of CML. A protein expressed by the Philadelphia chromosome shows elevated tyrosine kinase activity and is considered a tumorigenic factor. The first line of therapy that had been established for CML was "imatinib," a potent tyrosine kinase inhibitor. Various other second- and third-generation TKIs are taken into account in cases of imatinib failure/resistance. With the subsequent rise in the development of tyrosine kinase inhibitors, optimization in the treatment of CML and amplified total survival were observed throughout TKI dosage. As the disease progresses, additional chromosomal abnormalities (ACAs) have been reported, but their prognostic effect and impact on the response to treatment are still unknown. However, some substantial understandings have been achieved into the disease transformation mechanisms, including the role of somatic mutations, ACAs, and several different genomic mutations that occur during diagnosis or have evolved during treatment. The acquisition of ACAs impedes CML treatment. Due to additional chromosomal lesions, there are greater chances of future disease progression at the time of CML diagnosis beyond the Ph+ translocation. The synchronous appearance of two or more ACAs leads to lower survival and is classified as a poor prognostic group. The key objective of this review is to provide detailed insights into TKIs and their role in controlling Ph+ and ACAs, along with their response, treatment, overall persistence, and survival rate.

Real-world Management of CML: Outcomes and Treatment Patterns.

Chronic myeloid leukemia (CML) is a disease that previously signified a poor prognosis, but treatment options and outcomes have improved over the last several decades. Despite this, challenges remain in optimal management in clinical practice, as the characteristics in trial populations differ from patients who are treated in a real-world setting. This review describes recent updates in real-world treatment patterns and outcomes in patients with CML. Several analyses describing real-world practice patterns show that tyrosine kinase inhibitors (TKIs) are the most commonly prescribed agents in multiple lines of therapy. First-generation (1G) and second-generation (2G) TKIs are the most commonly prescribed, even in the third line and beyond. Third-generation (3G) TKIs are typically utilized in patients with resistant disease who are younger with fewer comorbidities. Hematopoietic stem cell transplant (HSCT) is utilized significantly less, given other treatment options available. The goals of treatment with CML have shifted to quality of life, cost savings, and treatment-free response (TFR). Despite clear guidelines for attempting TFR, discontinuation practice patterns remain inconsistent. TKIs are the mainstay of CML treatment, including those in later lines of therapy. In real-world practice, several challenges still remain with regard to optimal management. Specifically, ideal sequencing of treatments, side effect profiles of tyrosine kinase inhibitors (TKIs), current role and timing of transplant, and adherence to recommendations for attempting to achieve a treatment-free response (TFR). A national registry could characterize these practice patterns in order to find ways to optimize care for CML patients.

Design, synthesis, and cytotoxic activity of pyridine-based stilbenes

In the present study, three series of 35 pyridine-based stilbenes include 10 new compounds prepared by Horner-Wadsworth-Emmons (HWE) reaction were assayed for cytotoxic activities toward two tumoral cell lines (K562 and MDA-MB-231) and one non-tumoral cell line (L-02). The bioassay results indicated that hybrid stilbenes formed at the C-3 position of pyridine displayed stronger antiproliferative activities against K562 cells and C-4 pyridine-based stilbenes showed broad-spectrum cytotoxic effects. Among them, C-3 pyridine-based stilbene PS2g bearing 2,6-dimethoxy possessed extremely potent antiproliferative activity with IC50 values 1.46 µM against K562 cells, along with excellent selectivity towards normal L-02 cells. In summary, the present study contributes to the development of natural stilbene-based derivatives as antitumor agents and PS2g may serve as a promising lead for the treatment of chronic myeloid leukemia (CML) worthy further investigation.

Ruscogenin ameliorates dasatinib-induced intestinal barrier dysfunction via ErbB4/YAP and ROCK/MLC pathways.

Dasatinib is effective in the treatment of chronic and acute myeloid leukemia, which could cause the side effect of gastrointestinal bleeding by overdose or longtime use. Ruscogenin (RUS) from the traditional Chinese medicine Ophiopogon japonicas could protect endothelial microvascular barrier function. In this study, the therapeutic effect and underlying mechanisms of RUS were investigated on intestinal barrier dysfunction induced by dasatinib. Male C57BL/6J mice were given three doses of dasatinib (70, 140, 210mg/kg, ig) and RUS (3, 10, 30μg/kg, ip) to explore the effect of dasatinib on intestinal barrier and the intervention of RUS. It was proved that dasatinib could reduce intestinal blood flow, inhibit phosphorylation of EGFR family member v-erb-b2 avian erythroblastic leukemia viral oncogene homolog 4 (ErbB4)/YES-associated protein (YAP) and activation of Rho-associated coiled coil-containing protein kinase (ROCK)/phosphorylation of (myosin light chain) MLC. RUS could significantly increase intestinal blood flow, improve intestinal injury, reduce Evans blue leakage and serum content of FITC-dextran 4kDa, and increase the expression of connexin (ZO-1, Occludin and VE-cadherin). Meanwhile, the in vitro effect of RUS (0.01, 0.1, 1μM) on the dysfunction of the endothelial barrier was observed in dasatinib (150nM)-pretreated HUVECs. The results showed that RUS suppressed dasatinib-induced the leakage of Evans blue, and degradation of F-actin and connexin. Furthermore, RUS could significantly increase the phosphorylation of ErbB4 at Tyr1284 site and YAP at Ser397 site, and inhibit ROCK expression and phosphorylation of MLC at Ser19 site in vivo and in vitro. In conclusion, the present research proved that RUS could suppress the side effects of dasatinib-induced intestinal barrier dysfunction by regulating ErbB4/YAP and ROCK/MLC pathways.

#3939 EFFECTIVENESS OF IMATINIB FOR MCTO NEPHROPATHY

Abstract Background and Aims MAFB is a podocyte-specific transcription factor. Point mutations in the MAFB transactivation domain in humans result in multicentric carpometacarpal-tarsal osteolysis (MCTO). MCTO patients show focal segmental glomerulosclerosis (FSGS) due to podocyte damage, known as MCTO nephropathy. Effective treatment for MCTO has not been found. Imatinib is a tyrosine kinase inhibitor (TKI), which inhibits PI3K-Akt pathway, and is in long-term use for the treatment of chronic myeloid leukemia. Method In order to develop a new treatment for MCTO, we generated disease model mice using the CRISPR-Cas9 system. These animals have the same genetic mutation as human MCTO patients. Albuminuria was evaluated at 4 weeks of age, and renal histological analysis was performed at 26 weeks of age. In addition, RNA-seq for isolated glomeruli of 10-week-old MCTO mice and wild-type animal was performed for genetic and pathway analysis. Results MCTO mice exhibited growth retardation, and presented albuminuria from 4 weeks of age. Foot process effacement and FSGS-like renal histological changes were shown. Nephropathy symptoms were similar to that of human MCTO patients. Interestingly, the upregulated genes in RNA-seq analysis were a group of receptor genes associated with PI3K-Akt signaling, including lpar1 and csfr1.Transesophageal administration of imatinib, a PI3K-Akt pathway inhibitor, treatment for 5 consecutive weeks decreased albuminuria and ameliorated histological renal damage. RNA-seq of isolated glomeruli of MCTO mice after imatinib treatment showed decreased expression of genes associated with TGFβ-related signaling pathways compared to the non-treated group. Recently, enhanced PI3K-Akt signaling in podocytes has been linked to several renal diseases associated with podocyte injury. In addition, lpar1 inhibition in glomeruli is known to suppress TGFβ. Imatinib suppressed PI3K-Akt signaling, which is enhanced in podocytes of MCTO mice. This may have shown a podocyte-protective effect by suppressing fibrosis-related genes such as TGFβ. Imatinib is classified as a TKI, but frequency of podocyte toxicity is lower than other TKIs. Conclusion The podocyte injury mechanism of MCTO nephropathy is associated with enhanced PI3K-Akt signaling in podocytes. Imatinib inhibits this pathway and suppresses TGFβ. Imatinib may become a therapeutic agent for MCTO nephropathy.

Report of a chronic myeloid leukemia registry in a low-and middle-income setting.

7054 Background: Treatment of chronic myeloid leukaemia (CML) in Kenya has been supported since the year 2002 by a collaboration between the Max Foundation and Novartis Pharmaceuticals in the Glivec International Patient Assistance Program (GIPAP). In November 2020 this was transitioned to Max Access Solutions (MAS) that brought in the Ministry of Health as a partner. A broad range of BCR-ABL tyrosine kinase inhibitors are available. We wanted to describe epidemiology, treatment and outcome of CML in the country. Methods: Patients’ records were reviewed and data entered in a database. Key variables included age, sex, BMI, diet, disease phase at diagnosis, treatment, and outcome. Continuous variables were summarized using mean (standard deviation) or median (interquartile range). Categorical variables were summarized using counts and percentages. Bivariate comparisons of treatment outcome were done using chi-square or Fisher’s exact test. Analysis of variance (ANOVA) or Kruskal-Wallis test was used for continuous variables. Results: 1347 patients-males 748 (55.5%), females 599 (44.5%). Mean age was 44.5 years. Seventy (9.0%) were underweight, 88 (11.4%) obese. Mean body surface area (BSA) was 1.75m2. Chronic phase cases were 1177 (96.2%), accelerated phase 46 (3.8%), blastic phase 1 (0.1%). Mean bone marrow blast count was 5.25%, BCR-ABL/ABL was 63.7%, haemoglobin 10.8g/dl, total wbc count 225 x 109/litre, platelets 392.5 x 109/litre. Imatinib was administered upfront to 1319 patients (99.8%). Two hundred and six (15.3%) were switched to second line; 100 (48.8%) to dasatinib, 50 (24.4%) to bosutinib. Transformation was registered in 26 cases (1.9%) - accelerated in 13 (72.2%), blastic in 5 (27.8%), 4 (80.0%) being myeloid and 1 (20%) lymphoblastic. Those alive are 1151 (85.4%) and 185 (13.7%) lost to follow-up. Deaths were recorded in 11 (0.8%). Those with lower BSA were more likely to die (p = 0.01). Conclusions: CML in Kenya occurs at a younger age-group with a slight male preponderance. With availability of a range of BCR-ABL tyrosine kinase inhibitors, treatment outcome is close to what is documented in high-income settings.

Chronic myeloid leukemia, tyrosine kinase inhibitors and cardiovascular system.

Cardiovascular system health becomes important with the extended survival of chronic myeloid leukemia (CML) patients. Cardiotoxicities are related to the second- and third-generation tyrosine kinase inhibitors (TKIs). The most frequent and important cardiovascular events are myocardial infarction, stroke and peripheral arterial disease, QT prolongation, pleural effusions, and both systemic and pulmonary hypertension. The aim of this paper is to review the interactions between administrated TKIs and the cardiovascular system during the clinical course of CML. Elucidation of TKI effects on the cardiovascular system is vital since the current goal of CML therapy is a cure that leads to normal age and gender-similar survival with a normal quality of life. Up to August 2022, literature searches were performed via the internet search engines MEDLINE, EMBASE, GOOGLE SCHOLAR: (i) chronic myeloid leukemia; (ii) tyrosine kinase inhibitor; (iii) cardiovascular system. Only articles in English and research including humans were included in the search. Tailored TKI treatment with individual patient characteristics must account for CML disease risk, patient age, patient comorbidities, patient compliance, TKI drug off-target risk profile, accelerated or blastic phase CML disease, pregnancy and allografting in CML. The treatment-free survival, improving quality of life, limiting adverse events of TKIs, and the optimal dose and administration duration of TKIs are still a matter of controversy. Special attention should be paid to the comorbidities of CML patients and clinical TKI effects on CVS since the aim of CML treatment is a cure that leads to normal age and gender-similar survival with a "normal" quality of life. CVS is an important morbidity and mortality cause for adult patients. The discontinuation of TKI treatment in CML and the treatment-free remission of CML patients are very important in order to reduce the risk for cardiovascular adverse effects of TKIs. The frail CML patients and especially the patients who have cardiac comorbidities, should be carefully evaluated for TKI treatment, and hematopoietic stem cell transplantation (HSCT) should be the last choice in these risky CML patients. The current CML treatment target is a cure that leads to normal age and gender-adjusted survival with a "normal" quality of life. Cardiovascular disorders are one of the major obstacles to reaching this target in CML patients. The treatment choices for CML patients must include a cardiovascular perspective.

Financial toxicity and quality of life among people with chronic myeloid leukemia on tyrosine kinase inhibitors.

e18918 Background: Costs associated with treatment of Chronic Myeloid Leukemia (CML), along with out of pocket (OOP) expenses related to cancer care, put CML patients at risk for financial toxicity (FT). Although FT is considered a side effect of many cancer treatments, little is known about how FT affects quality of life among CML patients treated with Tyrosine Kinase Inhibitors (TKIs). In this study, we examined the association between FT, demographic factors, and health related quality of life (HRQOL). Methods: A secondary analysis was conducted using data from a parent study examining adherence trajectories in people with CML treated with TKIs. Descriptive, bivariate, and multivariate analyses were used to describe the sample, assess demographic and disease-specific FT correlates, and assess the predictive value of FT on HRQOL. FT was assessed by the Comprehensive Score for Financial Toxicity (COST Facit V2; higher scores were better) along with the Medical Expenditure Panel Survey (MEPS). HRQOL was assessed using the EuroQol 5-Dimension (EQ-5D-5L) single summary index score. Results: Of the 118 participant sample, about half were male (52%), White (57%), married (53%), and currently employed (59%) with a mean age of 49. Most had some college credit (76%). Many reported making financial sacrifices because of cancer costs (42% reduced spending on vacation/leisure activities, 31% delayed large purchases, 24% reduced spending on basics like food and clothing, and 27% used savings set aside for other purposes). Most (62%) reported ever being worried about having to pay large medical bills related to their cancer and 15% reported borrowing money or going into debt to cover cancer care costs. About half (51%) reported never discussing OOP costs for cancer care with their doctor. Overall, participants reported low FT (mean = 25, standard deviation = 11), but approximately 26% of respondents noted FT levels associated with significant financial burden (COST &lt; 17.5). In bivariate analyses, greater FT was associated with Black race, not married/partnered status, unemployed, high school education or less, and lower income. FT was not significantly associated with gender or age. In multivariable models, FT was significantly associated with HRQOL index (β = 0.011, SE = 0.002, P &lt; 0.001) after adjusting for individual characteristics. Age (β = -.003, SE = 0.001, P = 0.01) and education (β = .125, SE = 0.05, P = 0.027) also seemed to be important correlates of HRQOL index. Conclusions: Financial concerns are a common worry for individuals receiving treatment for CML. The association between FT and HRQOL suggests a need for assessing and addressing FT as part of routine care of people with CML who are taking TKIs. Further work is needed to understand the longitudinal experience of FT of people with CML on continuous treatment to help identify individuals who are most in need of intervention across the treatment continuum.

SA19 Real-World Targeted Literature Review of Intolerance with Tyrosine Kinase Inhibitor Treatment for Chronic Myeloid Leukemia

Clinical outcomes of patients with chronic myeloid leukemia (CML) have drastically improved with tyrosine kinase inhibitors (TKIs). However, one of the main challenges is the management of intolerance experienced by patients with CML treated with TKI, resulting in poorer disease control. This targeted literature review examined the association of intolerance to TKIs in CML and clinical, economic and humanistic outcomes in a real-world setting.