Practical management of patients with chronic myeloid leukemia receiving imatinib

Impact of systemic steroids on the efficacy of first line imatinib treatment of patients with advanced gastrointestinal stromal tumors (GISTs)

BACKGROUND

Effective management of adverse events is required to maintain sufficient imatinib dosing when treating patients with gastrointestinal stromal tumors (GISTs). Skin rash is a common adverse event of imatinib, which can be effectively controlled by systemic steroid treatment without imatinib dose modification or interruption. However, the impact of the use of systemic steroids on the efficacy of imatinib treatment remains unclear.

METHODS

Between October 2014 and February 2022, 277 consecutive patients from a prospective registry of GIST patients were included as the study population. Patients who started systemic steroids due to grade ≥ 3 skin rash or grade 2 skin rash with grade 2 pruritis were classified as the steroid group, whereas patients who did not develop a skin rash or those who did not require steroids for a mild skin rash were classified as the control group. Efficacy outcomes were compared between the two groups.

RESULTS

Among the 277 patients, 30 (10.8%) were treated with systemic steroids for skin rash. There was no significant difference in progression free survival (PFS) or overall survival (OS) between the steroid and control groups (3-year PFS, 67.7% vs. 65.1%, p = 0.53; 3-year OS, 91% vs. 89.9%, p = 0.67, respectively). The use of systemic steroids was not an independent factor associated with PFS (hazard ratio 0.73, 95% confidence interval 0.36-1.49, p = 0.39) and OS (hazard ratio 0.37, 95% confidence interval 0.12-1.18, p = 0.09). In the steroid group, patients who successfully maintained the imatinib dosage showed a trend toward more favorable survival outcomes than those who did not (3-year PFS, 73.3% vs. 44.4%, p = 0.34; 3-year OS, 95.8% vs. 75.0%, p = 0.15, respectively).

CONCLUSIONS

The use of systemic steroids for the control of imatinib induced severe skin rash did not adversely affect the efficacy outcomes of imatinib in patients with advanced GIST.

Effects of imidazole derivatives on cellular proliferation and apoptosis in myeloid leukemia

BACKGROUND

Acute promyelocytic leukemia (APL) is the sub-type of Acute myeloid leukemia (AML) which is described by differentiation block at promyelocytic stage and t(15; 17) translocation with All trans retinoic acid (ATRA) and arsenic trioxide (ATO) as standard treatments. Chronic myeloid leukemia (CML) translocation t (19; 22) causes a rise in granulocytes and their immature precursors in the blood. Different mutations cause resistance to first-line tyrosine kinase therapies in CML. Beside drug resistance, leukemia stem cells (LSC) are critical resources for relapse and resistance in APL and CML. The drug toxicity and resistant profile associated with LSC and current therapeutics of APL and CML necessitate the development of new therapies. Imidazoles are heterocyclic nitrogen compounds with diverse cellular actions. The purpose of this research was to assess the anti-leukemic properties of four novel imidazole derivatives including L-4, L-7, R-35, and R-NIM04.

METHODS AND RESULTS

Pharmacological and biochemical approaches were used which showed that all four imidazole derivatives interfere with the NB4 cells proliferation, an APL cell line, while only L-7 exhibit anti-proliferative activity against K562 cells, a CML cell line. The anti-proliferative effect of imidazole derivatives was linked to apoptosis induction. Further real-time polymerase chain reaction (RT-PCR) analysis revealed downregulation of AXL-Receptor Tyrosine Kinase (AXL-RTK) and target genes of Wnt/beta-catenin pathway like c-Myc, Axin2 and EYA3. An additive effect was observed after combinatorial treatment of L-7 with standard drugs ATRA or Imatinib on the proliferation of NB4 and K562 cells respectively which was related to further downregulation of target genes of Wnt/beta catenin pathway.

CONCLUSION

Imidazole derivatives significantly reduce proliferation of NB4 and K562 cells by inducing apoptosis, down regulating of AXL-RTK and Wnt/β-catenin target genes.

Ocular surface toxicities associated with modern anticancer therapies

Cancer treatments have recently shifted from broad-spectrum cytotoxic therapies to more focused treatments, maximizing anti-cancerous activity while reducing toxicity to healthy cells. These modern anticancer therapies (MATs) encompass a wide range of innovative molecules that mainly include immune checkpoint inhibitors (ICIs) and targeted anticancer therapies (TATs), comprising antibody drug conjugates (ADCs) and inhibitors of signal transduction (IST). Some MATs are associated with ocular surface (OS) adverse events (AEs) that can cause severe discomfort and even lead to loss of vision. While these complications remain rare, they're probably underreported. It is likely that both oncologists and ophthalmologists will come across MATs-associated OS-AEs in their practices, due to the increasing number of patients being treated with MATs. Rapid identification of OS-AEs is crucial, as early intervention can manage these conditions to avoid vision loss and reduce negative impacts on quality of life (QoL). We discuss characteristics of OS pathologies attributed to MATs, describe the suspected underlying pathophysiological mechanisms, and outline the main lines of treatment.

Bullous Pemphigoid Occurring after Stopping Imatinib Therapy of CML: Is a Continuation of Post-Treatment Follow-Up Needed?

Advancements and the use of tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of Chronic Myeloid Leukemia (CML), achieving unprecedented success rates and expanding their applications to various neoplasms. However, the use of TKIs is not without its drawbacks. Skin, gastrointestinal, and central nervous systems are particularly susceptible to adverse effects, including a higher incidence of autoimmune responses in treated individuals. In this report, we present a unique case of bullous pemphigoid, a rare autoimmune disease, which has not been previously associated with TKI therapy as an adverse effect, particularly appearing after discontinuing Imatinib® treatment.

Adverse effects of tyrosine kinase inhibitors in cancer therapy: pathophysiology, mechanisms and clinical management

Since their invention in the early 2000s, tyrosine kinase inhibitors (TKIs) have gained prominence as the most effective pathway-directed anti-cancer agents. TKIs have shown significant utility in the treatment of multiple hematological malignancies and solid tumors, including chronic myelogenous leukemia, non-small cell lung cancers, gastrointestinal stromal tumors, and HER2-positive breast cancers. Given their widespread applications, an increasing frequency of TKI-induced adverse effects has been reported. Although TKIs are known to affect multiple organs in the body including the lungs, liver, gastrointestinal tract, kidneys, thyroid, blood, and skin, cardiac involvement accounts for some of the most serious complications. The most frequently reported cardiovascular side effects range from hypertension, atrial fibrillation, reduced cardiac function, and heart failure to sudden death. The potential mechanisms of these side effects are unclear, leading to critical knowledge gaps in the development of effective therapy and treatment guidelines. There are limited data to infer the best clinical approaches for the early detection and therapeutic modulation of TKI-induced side effects, and universal consensus regarding various management guidelines is yet to be reached. In this state-of-the-art review, we examine multiple pre-clinical and clinical studies and curate evidence on the pathophysiology, mechanisms, and clinical management of these adverse reactions. We expect that this review will provide researchers and allied healthcare providers with the most up-to-date information on the pathophysiology, natural history, risk stratification, and management of emerging TKI-induced side effects in cancer patients.

Atypical Sweet syndrome: skin sinus tracts in an acutely febrile patient after lymphoma treatment: a case report

Sweet syndrome (SS) is an uncommon inflammatory disease that involves painful skin, edematous, red papules, plaques, or nodules often accompanied by fever and leukocytosis. SS has three subtypes, including classical, malignant-tumor associated, and drug-induced SS (DISS). Patients with DISS have clear histories of recent drug exposure. The incidence of SS is high in hematological malignancy but rare in lymphomas. Glucocorticoid treatment is the recommended treatment for all subtypes of SS. This case study describes a male patient who had a history of sALCL(Systemic anaplastic large cell lymphoma) and was treated with multiple cycles of monoclonal-antibody (mAb) therapy. They also received the G-CSF injection at the site where skin lesions later developed. They met the diagnosis criteria for DISS, which was considered to be caused by the G-CSF injection. In addition, BV(Brentuximab vedotin) administration might predispose them to DISS. This case illustrates the first reported SS during the lymphoma treatment, with rare clinical presentations of local crater-like suppurative skin lesions. This case expands the available literature on SS and hematologic neoplasms and reminds clinicians to promptly recognize and diagnose SS to minimize patient morbidity and long-term sequelae.

Molecular subtypes predict therapeutic responses and identifying and validating diagnostic signatures based on machine learning in chronic myeloid leukemia

Chronic myeloid leukemia (CML) is a hematological tumor derived from hematopoietic stem cells. The aim of this study is to analyze the biological characteristics and identify the diagnostic markers of CML. We obtained the expression profiles from the Gene Expression Omnibus (GEO) database and identified 210 differentially expressed genes (DEGs) between CML and normal samples. These DEGs are mainly enriched in immune-related pathways such as Th1 and Th2 cell differentiation, primary immunodeficiency, T cell receptor signaling pathway, antigen processing and presentation pathways. Based on these DEGs, we identified two molecular subtypes using a consensus clustering algorithm. Cluster A was an immunosuppressive phenotype with reduced immune cell infiltration and significant activation of metabolism-related pathways such as reactive oxygen species, glycolysis and mTORC1; Cluster B was an immune activating phenotype with increased infiltration of CD4 + and CD8 + T cells and NK cells, and increased activation of signaling pathways such as interferon gamma (IFN-γ) response, IL6-JAK-STAT3 and inflammatory response. Drug prediction results showed that patients in Cluster B had a higher therapeutic response to anti-PD-1 and anti-CTLA4 and were more sensitive to imatinib, nilotinib and dasatinib. Support Vector Machine Recursive Feature Elimination (SVM-RFE), Least Absolute Shrinkage Selection Operator (LASSO) and Random Forest (RF) algorithms identified 4 CML diagnostic genes (HDC, SMPDL3A, IRF4 and AQP3), and the risk score model constructed by these genes improved the diagnostic accuracy. We further validated the diagnostic value of the 4 genes and the risk score model in a clinical cohort, and the risk score can be used in the differential diagnosis of CML and other hematological malignancies. The risk score can also be used to identify molecular subtypes and predict response to imatinib treatment. These results reveal the characteristics of immunosuppression and metabolic reprogramming in CML patients, and the identification of molecular subtypes and biomarkers provides new ideas and insights for the clinical diagnosis and treatment.

Current childhood chronic myeloid leukemia management under tyrosine kinase inhibitor treatment

Chronic myeloid leukemia (CML) is very rare during childhood. Tyrosine kinase inhibitors (TKI) provide very good results in terms of survival. The medical records of 15 chronic phase (CP)-CML patients in a university hospital pediatric hematology department between 1997 and 2022 were reviewed retrospectively. Complete hematological response was documented in all patients between 20 and 68 (median 30) days of treatment. Major molecular response was achieved in seven patients within 6 months. Median follow-up for the study group was 79 (range 3-330) months and overall survival was 100%. Three patients (2 blastic transformation, 1 therapy resistant) underwent bone marrow transplantation (BMT) and one with blastic transformation is scheduled to undergo BMT. TKI were discontinued in three patients after a median of 86 (range 73-177) months. The complete molecular remission maintenance period before discontinuation of TKI was 81 (range 62-122) months. While no molecular relapse was seen before the last follow-up, the median overall follow-up period was 152 (range 131-300) months. In conclusion, recent advances have led to a very good prognosis for children with CP-CML. With TKI treatment, most patients continue their lives without disease progression. Additionally, in selected patients TKI can be discontinued without molecular relapse.

Outcome of pediatric chronic myeloid leukemia with management focusing on the monitoring of BCR-ABL fusion gene transcript levels

Background and objective

Clinical, laboratory and outcome data were reviewed for pediatric patients who were diagnosed with chronic myeloid leukemia (CML) and managed at two tertiary care hospitals in Saudi Arabia, between January 2011 and December 2017 to assess the response to tyrosine kinase inhibitors (TKI) focusing on the monitoring of BCR-ABL fusion gene transcript levels and to look at the overall outcome.

Methods

CML patients were identified based on the cytogenetic and molecular results.

Results

Twelve pediatric patients diagnosed with CML at a median age of 8.4 year; treated with TKI as first-line therapy, 11 (91.7%) patients were started with imatinib (first-generation TKI), while one received dasatinib (second-generation TKI) due to his three-way Philadelphia chromosome sensitivity. Eight patients (72.7%) starting on imatinib were switched to dasatinib (six patients due to drug resistance, and two patients due to intolerance of Imatinib) and two patients (25%) of whom had already achieved major molecular response (MMR) on Imatinib. Response rate to imatinib in terms of achieving MMR as first-line therapy was achieved in five out of 11 patients (45.5%) and only three of them continued to maintain their MMR. Six out of eight patients who were switched to dasatinib achieved MMR. Two patients underwent hematopoietic stem cell transplant (SCT): one due to blast crisis and one due to the side effects of TKI. With a median follow-up time of 78 months (range, 40.5–108), all of our patients were alive at last update.

Conclusion

We report an excellent outcome with an overall survival (OS) of 100% at 5-year and disease-free survival (DFS) of 91.7% (8.0%). All our patients achieved MMR and only one patient had loss of MMR on follow-up. Eight patients (66.7%) achieved complete molecular response (CMR).

Successful Treatment of Imatinib-Induced DRESS Syndrome Using Reslizumab without Cessation of Imatinib: A Case Report

Drug reaction with eosinophilia and systemic symptoms (DRESS) is a severe cutaneous adverse drug reaction; reported cases are sometimes imatinib mesylate induced. The main treatment is the withdrawal of the causative drug, and most cases with imatinib-induced DRESS syndrome required withdrawal of imatinib. However, in such cases involving anticancer drugs, this may compromise cancer treatment. Herein, we report a patient with imatinib-induced DRESS syndrome that was successfully treated with reslizumab while continuing imatinib treatment. A 65-year-old female presented with facial edema and generalized skin rash after being given 400 mg imatinib 2 weeks ago for metastatic gastrointestinal stromal tumor. After stopping imatinib, the clinical symptoms improved. Imatinib desensitization was performed, and it was administered again. However, the clinical symptoms reappeared more severely 2 months after restart of imatinib, and the peripheral absolute eosinophil count increased to 1,690/μL. A diagnosis of imatinib-induced DRESS syndrome was made, based on the Registry of Severe Cutaneous Adverse Reactions (RegiSCAR) criteria. Imatinib desensitization was repeated, but the clinical symptoms reappeared, and the peripheral eosinophilia persisted. We administered reslizumab, an interleukin-5 monoclonal antibody, without cessation of imatinib. The absolute eosinophil count decreased immediately, and the clinical symptoms improved gradually. After 2 weeks, the clinical symptoms reappeared mildly, but after administering reslizumab again, these disappeared completely. Reslizumab can be considered in the management of DRESS syndrome in cases wherein the causative medication needs to be continued.

Pharmacokinetics of Asciminib When Taken With Imatinib or With Food

Asciminib, a first-in-class, Specifically Targeting the Abelson kinase Myristoyl Pocket (STAMP) inhibitor with the potential to overcome resistance to adenosine triphosphate-competitive tyrosine kinase inhibitors, is being investigated in leukemia as monotherapy and in combination with tyrosine kinase inhibitors including imatinib. This phase 1 study in healthy volunteers assessed the pharmacokinetics of asciminib (40 mg single dose) under 2 conditions: when taken with imatinib (steady state; 400 mg once daily) and a low-fat meal (according to imatinib prescription information), or when taken as single-agent under different food conditions. Asciminib plus imatinib with a low-fat meal increased asciminib area under the plasma concentration-time curve from time 0 to infinity and maximum plasma concentration (geometric mean ratios [90% confidence interval], 2.08 [1.93-2.24] and 1.59 [1.45-1.75], respectively) compared with asciminib alone under the same food conditions. Asciminib plus food decreased asciminib area under the plasma concentration-time curve from time 0 to infinity compared with asciminib taken under fasted conditions (geometric mean ratios: low-fat meal, 0.7 [0.631-0.776]; high-fat meal, 0.377 [0.341-0.417]). Asciminib plus imatinib was well tolerated with no new safety signals. Overall, coadministration of asciminib with imatinib and a low-fat meal results in a moderate increase in asciminib exposure compared with asciminib alone under the same food condition. Food itself decreases asciminib exposure, indicating that single-agent asciminib should be administered in the fasted state to prevent potential suboptimal exposures.

Imatinib therapy for patients with recent-onset type 1 diabetes: a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial

BACKGROUND

Type 1 diabetes results from autoimmune-mediated destruction of β cells. The tyrosine kinase inhibitor imatinib might affect relevant immunological and metabolic pathways, and preclinical studies show that it reverses and prevents diabetes. Our aim was to evaluate the safety and efficacy of imatinib in preserving β-cell function in patients with recent-onset type 1 diabetes.

METHODS

We did a multicentre, randomised, double-blind, placebo-controlled, phase 2 trial. Patients with recent-onset type 1 diabetes (<100 days from diagnosis), aged 18-45 years, positive for at least one type of diabetes-associated autoantibody, and with a peak stimulated C-peptide of greater than 0·2 nmol L^-1 on a mixed meal tolerance test (MMTT) were enrolled from nine medical centres in the USA (n=8) and Australia (n=1). Participants were randomly assigned (2:1) to receive either 400 mg imatinib mesylate (4 × 100 mg film-coated tablets per day) or matching placebo for 26 weeks via a computer-generated blocked randomisation scheme stratified by centre. Treatment assignments were masked for all participants and study personnel except pharmacists at each clinical site. The primary endpoint was the difference in the area under the curve (AUC) mean for C-peptide response in the first 2 h of an MMTT at 12 months in the imatinib group versus the placebo group, with use of an ANCOVA model adjusting for sex, baseline age, and baseline C-peptide, with further observation up to 24 months. The primary analysis was by intention to treat (ITT). Safety was assessed in all randomly assigned participants. This study is registered with ClinicalTrials.gov, NCT01781975 (completed).

FINDINGS

Patients were screened and enrolled between Feb 12, 2014, and May 19, 2016. 45 patients were assigned to receive imatinib and 22 to receive placebo. After withdrawals, 43 participants in the imatinib group and 21 in the placebo group were included in the primary ITT analysis at 12 months. The study met its primary endpoint: the adjusted mean difference in 2-h C-peptide AUC at 12 months for imatinib versus placebo treatment was 0·095 (90% CI -0·003 to 0·191; p=0·048, one-tailed test). This effect was not sustained out to 24 months. During the 24-month follow-up, 32 (71%) of 45 participants who received imatinib had a grade 2 severity or worse adverse event, compared with 13 (59%) of 22 participants who received placebo. The most common adverse events (grade 2 severity or worse) that differed between the groups were gastrointestinal issues (six [13%] participants in the imatinib group, primarily nausea, and none in the placebo group) and additional laboratory investigations (ten [22%] participants in the imatinib group and two [9%] in the placebo group). Per the trial protocol, 17 (38%) participants in the imatinib group required a temporary modification in drug dosing and six (13%) permanently discontinued imatinib due to adverse events; five (23%) participants in the placebo group had temporary modifications in dosing and none had a permanent discontinuation due to adverse events.

INTERPRETATION

A 26-week course of imatinib preserved β-cell function at 12 months in adults with recent-onset type 1 diabetes. Imatinib might offer a novel means to alter the course of type 1 diabetes. Future considerations are defining ideal dose and duration of therapy, safety and efficacy in children, combination use with a complimentary drug, and ability of imatinib to delay or prevent progression to diabetes in an at-risk population; however, careful monitoring for possible toxicities is required.

FUNDING

Juvenile Research Diabetes Foundation.

Review of New-Generation Tyrosine Kinase Inhibitors for Chronic Myeloid Leukemia

PURPOSE OF REVIEW

In this review, we analyzed the available data from clinical trials with new tyrosine kinase inhibitors (TKIs) under development and how to consider chronic myeloid leukemia (CML) patients who had either resistance or intolerance to current TKIs for treatment with such agents.

RECENT FINDINGS

Nearly 50% of CML patients treated with TKIs frontline have required a change of therapy by 10 years. Second-line therapy is effective (by achievement of complete cytogenetic response) in only approximately 50% of patients, and available third-generation TKI has been marred by concerns of arterio-occlusive events. These facts highlight the need for additional treatment options. New TKIs have shown promising efficacy and tolerance in CML patients with resistance or intolerance to multiple available TKIs. Additional studies will determine their role in the management of CML.

Current status and novel strategy of CML

The advent of tyrosine kinase inhibitors (TKIs) has dramatically improved the outcome of patients with chronic myeloid leukemia (CML). Currently, four TKIs are available for the frontline treatment, including the first-generation TKI (imatinib) and the second-generation TKIs (dasatinib, nilotinib, and bosutinib). The second-generation TKIs lead to a faster and deeper molecular response without a survival benefit compared with imatinib. However, the opportunity for the treatment discontinuation and functional cure requires the achievement of durable deep molecular remission. Therefore, the second-generation TKIs should be considered as initial therapy for chronic-phase CML. Switch of therapy is warranted in case of treatment failure, including resistance and/or intolerance. The life expectancy of patients with CML is approaching that of the general population. Given an expected lifespan, future perspectives should consider the strategy for the optimal choice of TKIs, allowing for long-duration of effective TKI therapy with less toxicity to aim for a functional cure. A novel prediction approach such as artificial intelligence-driven analysis on the accumulated data from clinical trials paves a promising path for the personalized recommendation on frontline TKIs and precise survival prediction.

A Pilot Study on Probing of Imatinib Induced Platelet Dysfunction in Patients with Chronic Myeloid Leukemia-Chronic Phase and Absence of Associated Bleeding Manifestation: Trying to Solve an Enigma

Imatinib, the first Tyrosine Kinase Inhibitor (TKI) used for the treatment of chronic myeloid leukaemia (CML) has revolutionized the management by inhibiting BCR-ABL tyrosine kinase. According to earlier reports there are concerns regarding the adverse effect of imatinib on haemostasis by causing platelet dysfunction. Here we studied platelet function using platelet aggregometry, in 19 CML chronic phase (CML-CP) patients on imatinib therapy, in complete haematologic response (CHR). The median duration of imatinib therapy before performing the test was 154 days. This study reveals that there are large inter-individual variations in platelet functions among imatinib treated patients and different levels of variability have been seen for different agonists. Most common aggregation abnormality (< 50% aggregation) was seen with low dose collagen (1 μg/ml) in 31.57% patients. Despite in-vitro platelet aggregation defects, none of the patients showed any bleeding symptoms. This enigma can possibly be explained by the fact that platelet specific agonists, epinephrine and collagen act in synergy for platelet aggregation compared against individual low dose agonists, supported by ex-vivo experiments in normal healthy control group (n = 5) (p value < 0.0004 for epinephrine, p value < 0.0001 for collagen). This experiment was also confirmed in a CML-CP patient. In future, more studies are needed to find out the exact mechanism of this inhibition.

Pancreatic Insufficiency in Patients Under Sorafenib Treatment for Hepatocellular Carcinoma

GOALS

To describe the occurrence of malabsorption (MA) in hepatocellular carcinoma (HCC) patients under sorafenib, the potential relationship with pancreatic insufficiency (PI), and the role of pancreatic enzymes supplementation.

BACKGROUND

With the increasing options of second-line systemic therapies for HCC, the recognition of drug intolerance using practical tools is crucial. It has been proposed that a MA syndrome could be due to sorafenib-induced pancreatic dysfunction.

STUDY

All sorafenib-treated patients with suspicion of MA (defined as decreased stool consistency lasting >4 wk or presenting ≥10% body weight loss without HCC progression) were prospectively evaluated by serum markers, endoscopy, and imaging techniques.

RESULTS

We evaluated 81 sorafenib-treated patients and 21 developed MA suspicion (85.7% male, 81.5% Child-Pugh A, 52.4% BCLC-B, and 47.6% BCLC-C) within a median 5.9 months after starting sorafenib. The median treatment duration, follow-up, and overall survival after MA suspicion were 5.9, 20.3, and 20.3 months, respectively. Nine of them (42.9%) presented hyperparathyroidism secondary to vitamin D deficiency and 8 with PI. A gradual decrease in pancreatic volume of up to 19% was observed among patients with PI. Six of the 8 patients with PI received pancreatic enzymes, with complete recovery from MA symptoms and stabilization of pancreatic volume.

CONCLUSIONS

We validated the association between MA and PI in 10% of sorafenib-treated patients. Pancreatic enzymes supplementation successfully led to symptomatic recovery. Awareness of this adverse event can help in the management of sorafenib irrespective of cancer type and likely, of other tyrosine kinase inhibitors for HCC patients.

Diuretic-Resistant Ascites Following Laparoscopic Surgery in a Patient With Chronic Myeloid Leukemia on Imatinib Therapy

Imatinib mesylate is a tyrosine kinase inhibitor with high efficacy in the treatment of chronic myeloid leukemia (CML). Although fluid retention is a common adverse effect of imatinib, it rarely necessitates discontinuation of therapy. Isolated ascites has not been reported as a complication of imatinib therapy in patients with CML. Here, we report the case of a 72-year-old male with CML on imatinib (600 mg daily), who developed ascites two weeks after a laparoscopic hernia repair with intraperitoneal placement of a nylon mesh. The ascites was resistant to diuretic therapy and required repeated large-volume paracentesis. Discontinuation of imatinib resulted in arrest of ascites production, but reintroduction of the drug at the same dose two weeks later was rapidly followed by recurrence of ascites requiring further therapeutic paracenteses. It was postulated that peritoneal inflammation had resulted in increased capillary permeability, which was further augmented by imatinib via inhibition of platelet-derived growth factor receptor (PDGFR), a tyrosine kinase known to play a significant physiological role in the regulation of interstitial fluid pressure and capillary permeability. The possibility of developing ascites after abdominal surgery should be considered in patients receiving imatinib or related PDGFR inhibitors. In such cases, perioperative interruption of tyrosine kinase therapy might be indicated.

Chronic Conjunctival Chemosis-A New Ocular Side Effect of Crizotinib

Crizotinib, a targeted molecular therapy drug which inhibits tyrosine kinase, is approved for treatment of non-small cell lung carcinoma which has some ocular side effects like photopsia and delayed dark adaptation.This report documents a unique case of persistent conjunctival chemosis likely due to side effects of crizotinib therapy. A 64-year-old gentleman on crizotinib for metastatic adenocarcinoma of the lung presented with conjunctival chemosis in right eye which appeared 1 month after uneventful clear corneal phacoemulsification surgery. The patient was on crizotinib 250 mg twice a day started 2 months before cataract surgery. Clinical examination revealed marked inferior bulbar conjunctival edema of the right eye. Anterior segment optical coherence tomography, slit-lamp photographs, and magnetic resonance imaging orbit and systemic investigation were done to rule out other causes of conjunctival edema. Magnetic resonance imaging shows conjunctival and preseptal edema around both eye and thinning of the optic nerve in the right eye. Anterior segment optical coherence tomography revealed elevated hyper-reflective thickened conjunctival layer with dilated empty thin wall dark spaces of varying caliber. Chemosis was persisted for the next 3 months and not responded to oral acetazolamide, topical steroid and decongestive eyedrops. After 3 months, crizotinib was discontinued by oncologist due to drug intolerance and surprisingly within 1 week, the conjunctival edema was disappeared totally. To the best of the authors' knowledge, this is the first reported case of persistent unilateral non-inflammatory conjunctival chemosis caused by crizotinib. The physicians should be vigilant about these complications.

An ultra-long circulating nanoparticle for reviving a highly selective BCR-ABL inhibitor in long-term effective and safe treatment of chronic myeloid leukemia

Nanotechnology has demonstrated great promise for the development of more effective and safer cancer therapies. We recently developed a highly selective inhibitor of BCR-ABL fusion tyrosine kinase for chronic myeloid leukemia (CML). However, the poor drug-like properties were hurdles to its further clinical development. Herein, we re-investigate it by conjugating an amphiphilic polymer and self-assembling into a nanoparticle (NP) with a high loading (~10.3%). The formulation greatly improved its solubility and drastically extended its circulation half-life from ~5.3 to ~117 h (>20-fold). In the 150 days long-term engraftment model experiment, long intravenous dosing intervals of the NPs (every 4 or 8 days) exhibited much better survival and negligible toxicities as compared to daily oral administration of the inhibitor. Moreover, the NPs showed excellent inhibition of tumor growth in the subcutaneous xenograft model. All results suggest that the ultra-long circulating pro-drug NP may provide an effective and safe therapeutic strategy for BCR-ABL-positive CML.

Adherence to tyrosine kinase inhibitors among adult chronic myeloid leukemia patients in a Malaysia hospital

Background Tyrosine kinase inhibitors have been demonstrated to improve the survival of patients with chronic myeloid leukaemia. However, medication adherence is vital for patients on chronic treatment. Objective The objective of the current study was to evaluate response to treatment, adherence by patients to tyrosine kinase inhibitors and factors associated with adherence and response. Setting A haematology clinic in a regional referral hospital in Malaysia. Method Patients aged ≥ 13 years who had been on imatinib or nilotinib for ≥ 12 months were included in this cross-sectional study. An optimal response was defined as the achievement of major molecular response at 12 months of treatment. Patient medication adherence was determined using the average medication possession ratio based on the dispensing records. The patients were considered adherent if the medication possession ratio was > 90%. Multiple logistic regression was performed to evaluate the factors associated with adherence. The association of adherence with molecular response was analysed by univariate logistic regression. Main outcome measure The primary outcome measures were the proportion of patients who achieved optimal response and the medication possession ratio. Results A total of 151 patients were screened, and 71 patients were included. Twenty-eight patients (39%) achieved major molecular response at 12 months of treatment. The median time to achieve this was 15.5 months (an interquartile range of 15). The mean medication possession ratio for imatinib and nilotinib was 0.94 (± 0.14) and 0.96 (± 0.10), respectively, but this difference was without statistical significance (t  =  - 0.517, p  =  0.610). Nausea and vomiting (odds ratio [OR] of 0.25, 95% confidence interval [CI]: 0.07-0.83, p  =  0.023) and disease phase at diagnosis (OR of 0.20, 95% CI 0.04-1.06, p  =  0.059) were associated with patient adherence. An association was not found between patient adherence and molecular response (OR of 1.03, 95% CI 0.35-3.09, p  =  0.956). Conclusion The patients in this study demonstrated a relatively deep molecular response and optimal adherence. Nevertheless, one fourth of them were noncompliant with imatinib. Therefore, active interventions are warranted to prevent treatment-associated adverse events and improve adherence.

Therapeutic drug monitoring-based dose optimization for imatinib-associated serious cutaneous reactions in a patient with gastrointestinal stromal tumours: A case report

WHAT IS KNOWN AND OBJECTIVE

Imatinib mesylate (IM) is the first-line therapy for unresectable or metastatic gastrointestinal stromal tumours (GISTs). Here, we report a case of successful progressive dose optimization by therapeutic drug monitoring (TDM) for a patient with GISTs who developed IM-associated serious cutaneous reactions.

CASE DESCRIPTION

A 72-year-old female patient received IM at a dose of 400 mg/day for GISTs. The patient developed serious eczematoid drug eruptions and desquamation, following which IM was discontinued. One year later, the GISTs recurred with metastasis, and IM was re-administered at a dose of 100 mg/day, and the dose was gradually increased on the basis of TDM. The final dose of IM was 200 mg/day, and the trough concentration (C_trough ) of IM was 1457.76 ng/mL. The images obtained from follow-up computed tomography (CT) showed a marked anti-tumour response. IM was well tolerated and the patient developed tolerable IM-associated cutaneous reactions.

WHAT IS NEW AND CONCLUSION

The strategy of TDM-guided dose optimization makes it possible to achieve optimal clinical efficacy for patients with GISTs who develop IM-associated serious cutaneous reactions.

Marrow fibrosis is an independent predictor of hematological toxicity of tyrosine kinase inhibitors for the treatment of chronic myeloid leukemia

Hematological toxicity is a common adverse effect of tyrosine kinase inhibitors (TKIs) for the treatment of chronic myeloid leukemia (CML). We retrospectively investigated the incidence of hematological toxicity after TKI administration in 143 CML patients and parameters associated with hematological toxicity. Severe hematological toxicity (grade 3-4) existed in 26 (18.2%) patients. Marrow fibrosis (MF), age, Sokal score, and spleen enlargement were associated with severe hematological toxicity. Further multivariate analysis showed that only MF was an independent predictor. Complete cytogenetic response(CCyR) rates and major molecular response (MMR) rates with grade 3-4 hematological toxicity were 42.3% and 26.9%, respectively, significantly lower than patients with grade 1-2 and without hematological toxicity (p = .032 for CCyR and p = .044 for MMR). Similar results were observed regarding progression-free survival (PFS) and overall survival (OS) (p = .011 for PFS and p = .037 for OS). This study indicated that MF was an independent predictor of severe hematological toxicity of TKIs.

Response and Resistance to BCR-ABL1-Targeted Therapies

Chronic myeloid leukemia (CML), caused by constitutively active BCR-ABL1 fusion tyrosine kinase, has served as a paradigm for successful application of molecularly targeted cancer therapy. The development of the tyrosine kinase inhibitor (TKI) imatinib allows patients with CML to experience near-normal life expectancy. Specific point mutations that decrease drug binding affinity can produce TKI resistance, and second- and third-generation TKIs largely mitigate this problem. Some patients develop TKI resistance without known resistance mutations, with significant heterogeneity in the underlying mechanism, but this is relatively uncommon, with the majority of patients with chronic phase CML achieving long-term disease control. In contrast, responses to TKI treatment are short lived in advanced phases of the disease or in BCR-ABL1-positive acute lymphoblastic leukemia, with relapse driven by both BCR-ABL1 kinase-dependent and -independent mechanisms. Additionally, the frontline CML treatment with second-generation TKIs produces deeper molecular responses, driving disease burden below the detection limit for a greater number of patients. For patients with deep molecular responses, up to half have been able to discontinue therapy. Current efforts are focused on identifying therapeutic strategies to drive deeper molecular responses, enabling more patients to attempt TKI discontinuation.

Examining the Early Period Effect of Nilotinib on Hearing: An Experimental Study

OBJECTIVES

Nilotinib has very few side effects, including neutropenia, thrombocytopenia, cardiotoxicity, high pancreatic lipase, ischemia, and vascular occlusion. We aimed to investigate whether short-term administration of nilotinib had ototoxic effects in rats.

MATERIALS AND METHODS

Wistar-albino rats were categorized into three groups: group C (administered 0.25 mL of distilled water, no nilotinib), group N-20 (administered 20 mg/kg/day of nilotinib dissolved in distilled water), and group N-50 (administered 50 mg/kg/day of nilotinib dissolved in distilled water). A single dose was administered once per day, at the same hour, over 21 days. Auditory brainstem response (ABR) thresholds were recorded on day 0 and day 21.

RESULTS

There were no changes in ABR threshold values obtained on day 0 (baseline) and on day 21 across all three groups. A statistically significant difference was not found in terms of the mean latency of waves V and III, interpeak latency values of waves III-V, and amplitude ratios of waves III-V and V/Va at baseline and on day 21 across all three groups on within-group or between-group evaluation.

CONCLUSION

Consequently, further studies are needed that involve different drug doses, prolonged administration of drugs, as well as distortion otoacoustic emission test for the evaluation of cochlear activation and ABR. Furthermore, histopathological studies are needed to indicate whether the cochlea is affected to prove that nilotinib has definitively no ototoxic effect.

Co-delivery of rituximab targeted curcumin and imatinib nanostructured lipid carriers in non-Hodgkin lymphoma cells

The aim of the present study was production of nanostructured lipid carriers (NLCs) of curcumin and imatinib for co-administration in non-Hodgkin lymphoma cells. NLCs were prepared and conjugated to rituximab to target CD20 receptors of lymphoma cell lines. Oleic acid or Labrafac and glyceryl monostearate or lecithin were used for production of NLCs. The antibody coupling efficiency to NLCs and their physical characteristics were studied. The cytotoxicity of NLCs on Jurkat T cells (CD20 receptor negative) and Ramos B cells (CD20 receptor positive) was studied by MTT assay. The cellular uptake was determined by fluorescent microscopy. The results indicated both curcumin and imatinib targeted NLCs had a significant cytotoxic effect much higher than the free drugs and non-targeted NLCs on Ramos cells. In both cell lines, the cytotoxicity of the co-administrated drugs was significantly higher than each drug alone. In Ramos cells the co-administration of curcumin (15 μg/ml)/imatinib (5 μg/ml) decreased the free curcumin IC₅₀ from 8.3 ± 0.9 to 1.9 ± 0.2 μg/ml, and curcumin targeted NLCs from 6.7 ± 0.1 to 1.3 ± 0.2 μg/ml. In this case the IC₅₀ of imatinib was reduced from 11.1 ± 0.7 to 2.3 ± 0.1 μg/ml and imatinib targeted NLCs from 4.3 ± 0.1 to 1.4 ± 0.0 μg/ml. The co-administration of ritoximab conjugated NLCs of curcumin and imatinib may enhance cytotoxicity of imatinib in treatment of non-Hodgkin lymphoma.

Enhanced anticancer activity of combined treatment of imatinib and dipyridamole in solid Ehrlich carcinoma-bearing mice

The current study was designed to evaluate potential enhancement of the anticancer activity of imatinib mesylate (IM) with dipyridamole (DIP) and to investigate the underlying mechanisms of the combined therapy (IM/DIP) to reduce hepatotoxicity of IM in solid Ehrlich carcinoma (SEC)-bearing mice. SEC was induced in female albino mice as a model for experimentally induced breast cancer. Mice were randomly divided into seven groups (n = 10): SEC vehicle, IM₅₀ (50 mg/kg), IM₁₀₀ (100 mg/kg), DIP (35 mg/kg), a combination of IM₅₀/DIP and IM₁₀₀/DIP. On day 28th, mice were sacrificed and blood samples were collected for hematological studies. Biochemical determination of liver markers was evaluated. Glutamic oxaloacetic transaminase (SGOT), glutamic pyruvic transaminase (SGPT) and alkaline phosphatase (ALP) levels were assessed. In addition, MDR-1 gene expression and immunohistochemical staining of BAX and BCL-2 was done. Also, in vitro experiment for determination of IC50 of different treatments and combination index (CI) were assessed in both MCF-7 and HCT-116 cell lines. IM- and/or DIP-treated groups showed a significant reduction in tumor volume, weight, and serum levels of SGOT, SGPT, and AIP compared to vehicle group. In addition, reduction of VEGF, Ki67, and adenosine contents was also reported by treated groups. Also, IM/DIP combination showed lower IC50 than monotherapy. Combination index is less than 1 for IM/DIP combination in both cell lines. DIP as an adjuvant therapy potentiated the cytotoxic effect of IM, ameliorated its hepatic toxicity, and showed synergistic effect with IM in vitro cell lines. Furthermore, the resistance against IM therapy may be overcome by the use of DIP independent on mdr-1 gene expression.

Muscle Toxicity of Drugs: When Drugs Turn Physiology into Pathophysiology

Drugs are prescribed to manage or prevent symptoms and diseases, but may sometimes cause unexpected toxicity to muscles. The symptomatology and clinical manifestations of the myotoxic reaction can vary significantly between drugs and between patients on the same drug. This poses a challenge on how to recognize and prevent the occurrence of drug-induced muscle toxicity. The key to appropriate management of myotoxicity is prompt recognition that symptoms of patients may be drug related and to be aware that inter-individual differences in susceptibility to drug-induced toxicity exist. The most prevalent and well-documented drug class with unintended myotoxicity are the statins, but even today new classes of drugs with unintended myotoxicity are being discovered. This review will start off by explaining the principles of drug-induced myotoxicity and the different terminologies used to distinguish between grades of toxicity. The main part of the review will focus on the most important pathogenic mechanisms by which drugs can cause muscle toxicity, which will be exemplified by drugs with high risk of muscle toxicity. This will be done by providing information on key clinical and laboratory aspects, muscle electromyography patterns and biopsy results, and pathological mechanism and management for a specific drug from each pathogenic classification. In addition, rather new classes of drugs with unintended myotoxicity will be highlighted. Furthermore, we will explain why it is so difficult to diagnose drug-induced myotoxicity, and which tests can be used as a diagnostic aid. Lastly, a brief description will be given of how to manage and treat drug-induced myotoxicity.

Impact of L-carnitine on imatinib-related muscle cramps in patients with gastrointestinal stromal tumor

Introduction Muscle cramps constitute one of the leading adverse events of imatinib, the standard first-line treatment for advanced gastrointestinal stromal tumor (GIST). This study aims to assess the impact of L-carnitine on relieving cramps in patients with GIST taking imatinib. Materials and methods We reviewed our prospective database for patients with GIST who took L-carnitine (500-mg tablet, 2-3 times daily) for muscle cramps in Asan Medical Center. The assessment tool included severity by the numeric rating scale (NRS), frequency, duration of cramps, and questionnaire for the disturbance in basic activities of daily living (ADL), instrumental ADL (iADL), outdoor activity, or sleeping before and after L-carnitine treatment. Results We examined 42 patients [median age: 60 (range: 17-81) years; males, 52.4%] who received L-carnitine for cramps on NRS ≥ 4 intensity during 2016-2017. In 83.3% of patients (n = 35), the NRS score declined to <4 points, with 8 patients (19.0%) experiencing complete disappearance of symptoms [median response time: 10 (range: 2-30) days]. Moreover, the median duration of each episode and frequency decreased from 5 to 2 min and from 30 to 3 times per month (P < 0.001), respectively. We observed substantial improvement in all quality-of-life aspects after L-carnitine (ADL, 73.2%-14.6%; iADL, 73.2%-17.1%; sleeping, 78.0%-22.0%; outdoor activity, 68.3%-17.1%; P < 0.001). ConclusionL-carnitine could effectively relieve imatinib-related muscle cramps in patients with GIST. Accordingly, a randomized phase 3 study is currently ongoing (NCT03426722).

The MAP3K7-mTOR Axis Promotes the Proliferation and Malignancy of Hepatocellular Carcinoma Cells

Targeted therapy is currently limited for patients with hepatocellular carcinoma (HCC) due to the lack of suitable targets. Kinases play pivotal roles in many cellular biological processes, whereas dysregulation of kinases may lead to various diseases, particularly cancer. However, the role of kinases in HCC malignancy remains unclear. In this study, we employed a kinome small interfering RNA (siRNA) library, comprising 710 kinase-related genes, to screen whether any kinases were essential for cell proliferation in various HCC cell lines. Through a kinome siRNA library screening, we found that MAP3K7 was a crucial gene for HCC cell proliferation. Pharmacological or genetic ablation of MAP3K7 diminished the growth, migration, and invasion of HCC cells, including primary HCC cells. Stable knockdown of MAP3K7 attenuated tumor formation in a spheroid cell culture model and tumor xenograft mouse model. In addition, silencing MAP3K7 reduced the phosphorylation and expression of mammalian target of rapamycin (mTOR) in HCC cells. MAP3K7 expression was positively correlated with mTOR expression in tumors of patients with HCC. Higher co-expression of MAP3K7 and mTOR was significantly associated with poor prognosis of HCC. Taken together, our results revealed that the MAP3K7-mTOR axis might promote tumorigenesis and malignancy, which provides a potential marker or therapeutic target for HCC patients.

Novel Score-based Decision Approach in Chronic Myeloid Leukemia Patients After Acute Toxic Imatinib-induced Liver Injury

The tyrosine kinase inhibitor (TKI) imatinib in rare cases can cause acute toxic hepatitis, hepatic failure, and death. Currently, the choice of further chronic myeloid leukemia (CML) therapy in patients after acute hepatotoxicity is still a difficult question, which requires a complex individual approach based on the clinical guidelines of adverse event management. Data about the further follow-up strategy approach in patients with CML after acute toxic imatinib-induced liver injury are of concern, and at times controversial. In addition, one of the questions is about the necessity and safety of the imatinib therapy resumption after acute hepatotoxicity. In some publications, imatinib resumption without the recurrence of hepatotoxicity has been discussed; in others, imatinib resumption with the recurrence of imatinib hepatotoxicity has been mentioned. There are a few publications about the experience of administration of the second-line TKIs after acute imatinib hepatotoxicity. There are no clear data on which factors the physician's decision should be based on in patients with CML after acute toxic imatinib-induced liver injury. Imatinib should be restarted or withdrawn, when and for whom second-line therapy should be started. The physician's decision is usually based on the published data of similar cases, personal experience, and the severity of hepatotoxicity. We have discussed the clinical guidelines devoted to the peculiarities of the patient's management after acute toxic imatinib-induced hepatitis and main strategy approaches. A complex score-based decision algorithm for choosing the further strategy approach after acute toxic imatinib-induced hepatitis in patients with CML has been presented. The following parameters should be assessed: the grade of hepatotoxicity reaction, the presence of liver transplantation or imatinib-induced liver cirrhosis and its possible pathogenetic mechanism, the presence of early molecular response (EMR) to imatinib therapy defined as three-month BCR-ABL1 ≤10% according to the international scale (BCR-ABL1^IS ) or/and six-month BCR-ABL1 ^IS <1%; and the presence of the offender concomitant drug that probably caused the drug interaction with imatinib and the presence of viral hepatitis reactivation identified by polymerase chain reaction (PCR).

Association of oral mucosa hyperpigmentation with imatinib mesylate use: a cross-sectional study and a systematic literature review

OBJECTIVES

To assess the association between oral mucosa hyperpigmentation in patients with leukemia and imatinib mesylate use. Additionally, we compared our data to those obtained from a systematic review.

MATERIALS AND METHODS

A cross-sectional study was conducted with 74 patients undergoing treatment with imatinib mesylate. Sociodemographic characteristics, oral mucosa alterations, and medical history were evaluated. Oral hyperpigmentation was scored. The use of imatinib mesylate and hydroxyurea was evaluated. Association between oral hyperpigmentation and imatinib mesylate was assessed. A systematic review was also conducted to retrieve case reports or case series of patients with oral hyperpigmentation associated with imatinib mesylate.

RESULTS

Among the 74 participants, 41 were male (55.4%) and 33 were female (44.6%). Participants' mean age was 49.3 years. Sixty-six (89.2%) patients developed hyperpigmented lesions in the hard palate mucosa. In multivariate analysis, patients who had used imatinib mesylate for > 72 months had a hyperpigmentation score 1.62 times higher than those who had used this medication during a shorter period. Patients who had used hydroxyurea for > 30 days had a hyperpigmentation score 1.43 times higher than those who had used this medication during a shorter period. The systematic review retrieved 20 clinical cases of patients undergoing imatinib mesylate treatment and exhibiting oral hyperpigmentation.

CONCLUSIONS

The development of oral hyperpigmentation is associated with imatinib mesylate use. Hydroxyurea seems to increment such an association.

CLINICAL RELEVANCE

To assist providers in the differential diagnosis of hyperpigmented lesions associated with imatinib mesylate, as well as in the clinical management of such lesions.

Chinese consensus on management of tyrosine kinase inhibitor-associated side effects in gastrointestinal stromal tumors

Tyrosine kinase inhibitors (TKIs) have improved the overall survival of patients with gastrointestinal stromal tumors (GISTs), but their side effects can impact dose intensity and, consequently, the clinical benefit. To date, no guideline or consensus has been published on the TKI-associated adverse reactions. Therefore, the Chinese Society of Surgeons for Gastrointestinal Stromal Tumor of the Chinese Medical Doctor Association organized an expert panel discussion involving representatives from gastrointestinal surgery, medical oncology, cardiology, dermatology, nephrology, endocrinology, and ophthalmology to consider the systemic clinical symptoms, molecular and cellular mechanisms, and treatment recommendations of GISTs. Here, we present the resultant evidence- and experience-based consensus to guide the management of TKI-associated side events in clinical practice.

Imatinib and liver toxicity

Imatinib is a specific tyrosine kinase inhibitor which has been approved for the treatment of Philadelphia chromosome-positive chronic myeloid leukaemia and c-KIT (CD117)-positive gastrointestinal stromal tumours. It has been associated with hepatotoxicity ranging from abnormal liver function tests to acute liver failure along with chronic hepatitis B reactivation. We report the case of a patient who was started on adjuvant treatment with imatinib following resection of a primary gastrointestinal stromal cell tumour of jejunum and developed severe hepatotoxicity. There was no history of risk factors for liver disease, and a search for the underlying causes of hepatotoxicity was unremarkable. Imatinib was stopped and she was treated with steroids which resulted in dramatic improvement of liver function tests. Liver biopsy in this case was not performed because liver function tests improved following discontinuation of imatinib and treatment with steroids. Repeat imaging did not reveal any evidence of tumour recurrence.

Сase Report of Acute Toxic Imatinib-induced Hepatitis in a Patient with Chronic Myeloid Leukemia, Sulfa Allergy, and Rheumatoid Arthritis

The introduction of imatinib has substantially changed the approaches to the therapy of chronic myeloid leukemia. However, this drug can cause hepatic failure and death in rare cases. This report describes a clinical case of acute, toxic imatinib-induced hepatitis in a 56-year-old woman with chronic myeloid leukemia and concomitant sulfa allergy and rheumatoid arthritis. The patient developed acute imatinib-induced hepatitis after three months of treatment with imatinib and three days after increasing the imatinib dosage from 400 mg per day to 600 mg per day, resolving within three months after imatinib discontinuation and prednisolone administration. This confirms the necessity of great caution during imatinib therapy and the monitoring of liver tests. Approximately 25 reports about clinical cases of imatinib-induced hepatitis have been published up to the present.

Reduced tyrosine kinase inhibitor dose is predicted to be as effective as standard dose in chronic myeloid leukemia: a simulation study based on phase III trial data

Continuing tyrosine kinase inhibitor (TKI)-mediated targeting of the BCR-ABL1 oncoprotein is the standard therapy for chronic myeloid leukemia (CML) and allows for a sustained disease control in the majority of patients. While therapy cessation for patients appeared as a safe option for about half of those patients with optimal response, no systematic assessment of long-term TKI dose de-escalation has been made. We use a mathematical model to analyze and consistently describe biphasic treatment responses from TKI-treated patients from two independent clinical phase III trials. Scale estimates reveal that drug efficiency determines the initial response while the long-term behavior is limited by the rare activation of leukemic stem cells. We use this mathematical framework to investigate the influence of different dosing regimens on the treatment outcome. We provide strong evidence to suggest that TKI dose de-escalation (at least 50%) does not lead to a reduction of long-term treatment efficiency for most patients, who have already achieved sustained remission, and maintains the secondary decline of BCR-ABL1 levels. We demonstrate that continuous BCR-ABL1 monitoring provides patient-specific predictions of an optimal reduced dose without decreasing the anti-leukemic effect on residual leukemic stem cells. Our results are consistent with the interim results of the DESTINY trial and provide clinically testable predictions. Our results suggest that dose-halving should be considered as a long-term treatment option for CML patients with good response under continuing maintenance therapy with TKIs. We emphasize the clinical potential of this approach to reduce treatment-related side-effects and treatment costs.

Front-line imatinib treatment in children and adolescents with chronic myeloid leukemia: results from a phase III trial

A total of 156 patients (age range 1.3-18.0 years, median 13.2 years; 91 (58.3%) male) with newly diagnosed CML (N = 146 chronic phase (CML-CP), N = 3 accelerated phase (CML-AP), N = 7 blastic phase (CML-BP)) received imatinib up-front (300, 400, 500 mg/m², respectively) within a prospective phase III trial. Therapy response, progression-free survival, causes of treatment failure, and side effects were analyzed in 148 children and adolescents with complete data. Event-free survival rate by 18 months for patients in CML-CP (median follow-up time 25 months, range: 1-120) was 97% (95% CI, 94.2-99.9%). According to the 2006 ELN-criteria complete hematologic response by month 3, complete cytogenetic response (CCyR) by month 12, and major molecular response (MMR) by month 18 were achieved in 98, 63, and 59% of the patients, respectively. By month 36, 86% of the patients achieved CCyR and 74% achieved MMR. Thirty-eight patients (27%) experienced imatinib failure because of unsatisfactory response or intolerance (N = 9). In all, 28/148 patients (19%) underwent stem cell transplantation (SCT). In the SCT sub-cohort 2/23 patients diagnosed in CML-CP, 0/1 in CML-AP, and 2/4 in CML-BP, respectively, died of relapse (N = 3) or SCT-related complications (N = 2). This large pediatric trial extends and confirms data from smaller series that first-line imatinib in children is highly effective.

A Robust Optimization Approach to Cancer Treatment under Toxicity Uncertainty

The design of optimal protocols plays an important role in cancer treatment. However, in clinical applications, the outcomes under the optimal protocols are sensitive to variations of parameter settings such as drug effects and the attributes of age, weight, and health conditions in human subjects. One approach to overcoming this challenge is to formulate the problem of finding an optimal treatment protocol as a robust optimization problem (ROP) that takes parameter uncertainty into account. In this chapter, we describe a method to model toxicity uncertainty. We then apply a mixed integer ROP to derive the optimal protocols that minimize the cumulative tumor size. While our method may be applied to other cancers, in this work we focus on the treatment of chronic myeloid leukemia (CML) with tyrosine kinase inhibitors (TKI). For simplicity, we focus on one particular mode of toxicity arising from TKI therapy, low blood cell counts, in particular low absolute neutrophil count (ANC). We develop optimization methods for locating optimal treatment protocols assuming that the rate of decrease of ANC varies within a given interval. We further investigated the relationship between parameter uncertainty and optimal protocols. Our results suggest that the dosing schedule can significantly reduce tumor size without recurrence in 360 weeks while insuring that toxicity constraints are satisfied for all realizations of uncertain parameters.

Late onset of unilateral optic disk edema secondary to treatment with imatinib mesylate

Prompt ophthalmology evaluation and immediate imatinib suspension should be suggested at any time of tyrosine kinase inhibitor therapy in patients with visual deficit, as it may be a clinical manifestation of optic disk edema, and suspension may help in prompt recovery.

Clinical Pharmacokinetics and Pharmacodynamics of Bosutinib

Chronic myeloid leukemia (CML) is a clonal myeloproliferative stem cell disorder. Bosutinib is an oral, once-daily SRC/ABL tyrosine kinase inhibitor with very potent inhibitory activity. Bosutinib is effective against all phases of intolerant or resistant Philadelphia chromosome-positive CML that do not harbor the T315I or V299LABL kinase domain mutations. Peak plasma concentrations of bosutinib occur at 4-6 h following oral administration, and dose-proportional increases in exposure are observed at doses ranging from 200 to 800 mg. Absorption of bosutinib increases with food. Bosutinib is distributed extensively into the tissues. It is highly plasma protein bound (94 %) and is primarily metabolized in the liver by cytochrome P450 3A4. Bosutinib is well tolerated overall and has a unique but manageable toxicity profile. This article provides a review of the available clinical pharmacokinetic, pharmacodynamic, and drug-drug interaction data on bosutinib in healthy subjects, patients with CML, and special populations.

Understanding and Challenges in Taking Tyrosine Kinase Inhibitors among Malaysian Chronic Myeloid Leukemia Patients: A Qualitative Study

Background:

In Malaysia, the treatment for chronic myeloid leukemia (CML) has long been delivered under the Malaysian Patient Assistance Program (MYPAP), but research on identifying factors contributing to non-adherence to tyrosine kinase inhibitors (TKIs) is still limited. The current study explored understanding and challenges of Malaysian CML patients in taking imatinib and nilotinib.

Methods:

Semi-structured, face-to-face interviews were conducted with 13 CML patients receiving treatment at a public tertiary care center, and were analyzed using the content analysis approach.

Results:

The patients generally demonstrated inadequate knowledge, particularly of the natural history and staging of CML, the function of TKIs, and the methods used for monitoring the effectiveness of treatment. A number of them also had experiences of withholding, skipping or altering the treatment, mainly due to the life-disturbing adverse drug effects (ADRs), forgetfulness, and religious and social issues. Besides, most of them were found having limited skills in managing the ADRs, and not using prompts as reminders to take the medications. Furthermore, even though nilotinib was generally perceived as better tolerated as compared with imatinib, the inconvenience caused by the need to take it twice daily and on an empty stomach was constantly highlighted by the patients.

Conclusion:

While TKIs are widely used for CML treatment in Malaysia, the findings have revealed a lack of patient education and awareness, which warrants an integrated plan to reinforce medication adherence.

Cutaneous Adverse Events of Targeted Therapies for Hematolymphoid Malignancies

The identification of oncogenic drivers of liquid tumors has led to the rapid development of targeted agents with distinct cutaneous adverse event (AE) profiles. The diagnosis and management of these skin toxicities has motivated a novel partnership between dermatologists and oncologists in developing supportive oncodermatology clinics. In this article we review the current state of knowledge of clinical presentation, mechanisms, and management of the most common and significant cutaneous AEs observed during treatment with targeted therapies for hematologic and lymphoid malignancies. We systematically review according to drug-targeting pathway the cutaneous AE profiles of these drugs, and offer insight when possible into whether pharmacologic target versus immunologic modulation primarily underlie presentation. We include discussion of tyrosine kinase inhibitors (imatinib, dasatinib, nilotinib, bosutinib, ponatinib), blinatumomab, ibrutinib, idelalisib, anti-B cell antibodies (rituximab, ibritumomab, obinutuzumab, ofatumumab, tositumomab), immune checkpoint inhibitors (nivolumab, pembrolizumab), alemtuzumab, brentuximab, and proteasome inhibitors (bortezomib, carfilzomib, ixazomib). We highlight skin reactions seen with antiliquid but not solid tumor agents, draw attention to serious cutaneous AEs that might require therapy modification or cessation, and offer management strategies to permit treatment tolerability. We emphasize the importance of early diagnosis and treatment to minimize disruptions to care, optimize prognosis and quality of life, and promptly address life-threatening skin or infectious events. This evolving partnership between oncologists and dermatologists in the iterative characterization and management of skin toxicities will contribute to a better understanding of these drugs' cutaneous targets and improved patient care.

Genetic Polymorphisms Contribute to the Individual Variations of Imatinib Mesylate Plasma Levels and Adverse Reactions in Chinese GIST Patients

Imatinib mesylate (IM) has dramatically improved the outcomes of gastrointestinal stromal tumor (GIST) patients. However, the clinical responses of IM may considerably vary among single individuals. This study aimed to investigate the influences of genetic polymorphisms of drug-metabolizing enzyme (CYP3A4), transporters (ABCB1, ABCG2), and nuclear receptor (Pregnane X Receptor (PXR, encoded by NR1I2)) on IM plasma levels and related adverse reactions in Chinese GIST patients. A total of 68 Chinese GIST patients who have received IM 300–600 mg/day were genotyped for six single nucleotide polymorphisms (SNPs) (CYP3A4 rs2242480; ABCB1 rs1045642; ABCG2 rs2231137; NRI12 rs3814055, rs6785049, rs2276706), and the steady-state IM trough plasma concentrations were measured by a validated HPLC method. There were statistically significant variances in the steady-state IM trough plasma concentrations (from 272.22 to 4365.96 ng/mL). Subjects of GG in rs2242480, T allele carriers in rs1045642 and CC in rs3814055 had significantly higher steady-state IM dose-adjusted trough plasma concentrations. Subjects of CC in rs3814055 had significantly higher incidence rate of edema. The genetic polymorphisms of rs2242480, rs1045642, rs3814055 were significantly associated with IM plasma levels, and the genetic variations of rs3814055 were significantly associated with the incidence rate of edema in Chinese GIST patients. The current results may serve as valuable fundamental knowledge for IM therapy in Chinese GIST patients.

A case report of rare palmoplantar keratosis and nail dystrophy with imatinib

A 48-year-old woman developed palmoplantar hyperkeratosis during treatment with imatinib (400mg/day) for treatment of chronic myeloid leukemia. After 5months of treatment, she developed plantar lesions with yellow-brownish plaques and palmar desquamations. The skin biopsy has eliminated psoriasis. Imatinib was discontinued, and treatment with an emollient balm and a soothing repair cream with an improvement of symptoms. A French imputability assessment score of I3 was obtained, indicating a probable relationship between the side effect and imatinib. In our case, the skin adverse events require definitive drug discontinuation and change of treatment.