Matching-adjusted indirect comparison of asciminib versus other treatments in chronic-phase chronic myeloid leukemia after failure of two prior tyrosine kinase inhibitors

Asciminib: the tyrosine kinase inhibitor with a unique mechanism of action

INTRODUCTION

Management of chronic phase chronic myeloid leukemia (CML-CP) was revolutionized with the development of tyrosine kinase inhibitors (TKIs). Imatinib (first generation), dasatinib, nilotinib and bosutinib (second generation), and ponatinib (third generation) are the five approved TKIs that inhibit BCR::ABL1 by binding to the ATP binding site of ABL1. About half of the resistance to TKIs develops through acquisition of mutations in the ATP binding site, including T315I. Hence, a novel TKI with a distinct mechanism of action that inhibits bcr-abl1 by specifically targeting the ABL1 myristoyl pocket (STAMP inhibitor) was developed.

AREAS COVERED

Asciminib was first approved for treatment of CML-CP in the third line setting or beyond and in patients with T315I mutation in October, 2021. More recently, in October, 2024, asciminib was approved for newly diagnosed CML-CP based on ASC4FIRST data showing MMR rate of 67.7% in the asciminib arm compared to 49% in the investigator choice TKI arm (p < 0.001) at 48 weeks. In this review we detail the mechanism of action, preclinical data, clinical data, safety, and tolerability of asciminib.

EXPERT OPINION

Due to its mechanism of action, asciminib has fewer off-target effects, resulting in an improved safety and tolerability profile.

Asciminib in the treatment of chronic myeloid leukemia in chronic phase

In the evolving therapeutic landscape of chronic myeloid leukemia (CML), asciminib stands out as a critical treatment option. Its ability to bind to and allosterically modulate the myristoyl pocket of BCR::ABL1 enables asciminib to effectively overcome resistance to conventional tyrosine kinase inhibitors (TKIs). Asciminib has shown significant cytogenetic and molecular responses in heavily pretreated patients, those previously exposed to ponatinib, and treatment-naïve individuals, attributed to its pharmacological selectivity and generally favorable safety profile. Asciminib also offers a compelling alternative for patients with a history of cardiovascular events or unfavorable cardiovascular profiles. However, extended follow-up in ongoing trials is necessary for a thorough assessment of its long-term benefits. Mutations in the myristoyl pocket, such as A337V/T and I502L, along with kinase domain mutations, including F359C/I/V at the kinase-SH2 interface and M244V in the N-lobe, have demonstrated the ability to undermine asciminib effectiveness in clinical practice, highlighting the importance of mutational assessment before starting treatment. This review provides an in-depth analysis of the preclinical and clinical evidence supporting the use of asciminib, synthesizing findings from a targeted literature search of PubMed and Web of Science. Our discussion integrates insights into its mechanism of action, clinical efficacy, safety, resistance patterns, and future directions.

Safety and efficacy of asciminib in a patient with chronic myeloid leukemia on hemodialysis

The advent of tyrosine kinase inhibitors (TKIs) has revolutionized the treatment of chronic myeloid leukemia (CML), significantly improving patient prognosis. Asciminib, a novel specifically targeting the ABL myristoyl pocket inhibitor, has shown promise for CML patients unresponsive or intolerant to traditional TKIs. However, its use in hemodialysis patients remains underexplored. We present a case of a 71-year-old man with CML undergoing hemodialysis, successfully treated with asciminib. Initial treatment with bosutinib was effective but later failed, prompting a switch to asciminib. The patient achieved a major molecular response within 2 months without adverse effects. Pharmacokinetic analysis revealed significant drug clearance during hemodialysis, necessitating dosage adjustments. This case highlights the potential of asciminib in managing CML in hemodialysis patients, emphasizing the need for individualized treatment plans and close monitoring. Further studies are warranted to establish comprehensive guidelines for asciminib use in this unique patient population.

Clinical Pharmacology of Asciminib: A Review

Asciminib is a first-in-class allosteric inhibitor of the kinase activity of BCR::ABL1, specifically targeting the ABL myristoyl pocket (STAMP). This review focuses on the pharmacokinetic (PK) and pharmacodynamic data of asciminib, which is approved at a total daily dose of 80 mg for the treatment of adult patients with chronic myeloid leukemia in chronic phase who are either resistant or intolerant to ≥ 2 tyrosine kinase inhibitors or those harboring the T315I mutation (at a dose of 200 mg twice daily). Asciminib is predicted to be almost completely absorbed from the gut, with an absolute bioavailability (F) of approximately 73%. It should be administered in a fasted state, as food (particularly high-fat meals) reduces exposure. Asciminib displays a slightly greater than dose-proportional increase in exposure, with no time-dependent changes in PK observed following repeated dosing. This drug shows low clearance (6.31 L/h), with a moderate volume of distribution (111 L) and high human plasma protein binding (97.3%). The apparent terminal elimination half-life (t1/2) across studies was estimated to be between 7 and 15 h. The PK of asciminib is not substantially affected by body weight, age, gender, race, or renal or hepatic impairment. Asciminib is primarily metabolized via CYP3A4-mediated oxidation (36.0%) and UGT2B7- and UGT2B17-mediated glucuronidation (13.3% and 7.8%, respectively); biliary secretion via breast cancer resistance protein contributes to about 31.1% to total systemic clearance, which is mainly through hepatic metabolism and biliary secretion through the fecal pathway, with renal excretion playing a minor role. The potential for PK drug interaction for asciminib both as a victim and a perpetrator has been summarized here based on clinical and predicted drug-drug interaction studies. Robust exposure-response models characterized asciminib exposure-efficacy and exposure-safety relationships. In patients without the T315I mutation, the exposure-efficacy analysis of the time course of BCR::ABL1IS percentages highlighted the existence of a slightly positive, albeit not clinically significant, relationship. Higher exposure was required for efficacy in patients harboring the T315I mutation compared with those who did not. The exposure-safety relationship analysis showed no apparent association between exposure and adverse events of interest over the broad range of exposure or dose levels investigated. Asciminib has also been shown to have no clinically relevant effect on cardiac repolarization. Here, we review the clinical pharmacology data available to date for asciminib that supported its clinical development program and regulatory applications.

Asciminib for third-line treatment of chronic myeloid leukemia: Cost-effectiveness analysis based on treatment-free remission approach

INTRODUCTION

The first targeted therapy in oncology, imatinib, revolutionized chronic myeloid leukemia (CML) treatment and spurred research in targeted therapies for various cancers. CML results from a chromosomal translocation, forming the BCR-ABL1 fusion gene. Asciminib has been recently approved for 3rd-line refractory or intolerant patients. Treatment-free remission (TFR) is attainable with sustained deep molecular response (DMR) and this approach could be incorporated into pharmacoeconomic models.

AIMS

To establish a cost-effectiveness model comparing asciminib to approved third-generation tyrosine kinase inhibitors (TKIs) (bosutinib and ponatinib) with a focus on achieving TFR. Additionally, the budgetary impact of incorporating asciminib as a therapeutic alternative is assessed.

METHODS

This model is based on a Markov chain with seven states. The condition for achieving TFR is to remain for 5 years in DMR state. Efficacy of the model was measured in QALYs, and the costs included in the base case analysis are based in Spain. A probabilistic (PSA) and deterministic analysis (DSA) were carried out to assess the variability of the model. There were achieved two independent models comparing asciminib vs. bosutinib and asciminib vs. ponatinib.

RESULTS

Asciminib, when compared with ponatinib, is a cost-saving alternative, as efficacy is similar between alternatives, and asciminib has a lower cost of 30,275 €. Asciminib showed 4.33 more QALYs and a higher cost (203,591 €) than bosutinib, resulting in an ICER of €47,010.49 per QALY. PSA shows that the parameters with higher influence in the variability of the model were the probability of transitioning to BP and probabilities of achieving MMR and DMR. A one-way analysis reports that the drug cost has a higher influence on both models, and the discount rate significantly affects the asciminib vs. bosutinib model.

CONCLUSION

Asciminib broadens therapeutic choices for patient's refractory or intolerant to two prior lines of treatment in a cost-effective manner. The costs of drugs significantly impact the overall cost of the disease, emphasizing the importance of the selected discount rates for each drug. Given the relatively low incidence of CML, the introduction of asciminib has a limited budgetary impact, warranting individualized decisions based on patient`s clinical characteristics.

Asciminib for third-line treatment of chronic myeloid leukemia: Cost-effectiveness analysis based on treatment-free remission approach

INTRODUCTION

The first targeted therapy in oncology, imatinib, revolutionized chronic myeloid leukemia (CML) treatment and spurred research in targeted therapies for various cancers. CML results from a chromosomal translocation, forming the BCR-ABL1 fusion gene. Asciminib has been recently approved for third-line refractory or intolerant patients. Treatment-free remission (TFR) is attainable with sustained deep molecular response (DMR) and this approach could be incorporated into pharmacoeconomic models.

AIMS

To establish a cost-effectiveness model comparing asciminib to approved third-generation tyrosine kinase inhibitors (TKIs) (bosutinib and ponatinib) with a focus on achieving TFR. Additionally, the budgetary impact of incorporating asciminib as a therapeutic alternative is assessed.

METHODS

This model is based on a Markov chain with 7 states. The condition for achieving TFR is to remain for 5 years in DMR state. Efficacy of the model was measured in QALYs, and the costs included in the base case analysis are based in Spain. A probabilistic (PSA) and deterministic analysis (DSA) were carried out to assess the variability of the model. There were achieved 2 independent models comparing asciminib vs bosutinib and asciminib vs ponatinib.

RESULTS

Asciminib, when compared with ponatinib, is a cost-saving alternative, as efficacy is similar between alternatives, and asciminib have a lower cost of 30,275€. Asciminib showed 4.33 more QALYs and a higher cost (203,591€) than bosutinib, resulting in an ICER of €47,010.49 per QALY. PSA shows that the parameters with higher influence in the variability of the model were the probability of transitioning to BP and probabilities of achieving MMR and DMR. A one-way analysis reports that the drug cost has a higher influence on both models, and the discount rate significantly affects the asciminib vs bosutinib model.

CONCLUSION

Asciminib broadens therapeutic choices for patient's refractory or intolerant to 2 prior lines of treatment in a cost-effectiveness manner. The costs of drugs significantly impact the overall cost of the disease, emphasizing the importance of the selected discount rates for each drug. Given the relatively low incidence of CML, the introduction of asciminib has a limited budgetary impact, warranting individualized decisions based on patient`s clinical characteristics.

Real-World Disproportionality Analysis of the Food and Drug Administration Adverse Event Reporting System Database for Asciminib

INTRODUCTION

Asciminib is primarily utilized for treating Philadelphia chromosome-positive chronic myeloid leukemia in its chronic phase among patients harboring the T315I mutation or those who have been previously treated with at least two tyrosine kinase inhibitors. The safety profile of asciminib across a broad patient population over an extended timeframe remains unverified. This study uses a real-world pharmacovigilance database to evaluate the adverse events (AEs) linked with asciminib, providing valuable insights for clinical drug safety.

METHODS

Data from the FDA Adverse Event Reporting System (FAERS) database, spanning from October 2021 to December 2023, served as the basis for this analysis. The extent of disproportional events was assessed using sophisticated metrics such as the reporting odds ratio, proportional reporting ratio, information component, and empirical Bayesian geometric mean.

RESULTS

Within the specified period, the FAERS database documented 3,913,574 AE reports, with asciminib being associated with 966 incidents. Reactions to asciminib spanned 27 system organ categories. Utilizing four distinct analytical algorithms, 663 significant preferred terms exhibiting disproportional frequencies were identified. Notably, this investigation uncovered 26 significant AEs linked to off-label asciminib use, encompassing conditions such as gynecomastia, nephrotic syndrome, orchitis, pyelonephritis, hepatotoxicity, and pancreatitis. The median onset time for asciminib-related AEs was 52.5 days, ranging from 17 to 122.75 days.

CONCLUSION

The study sheds light on additional potential AEs associated with asciminib use, warranting further research to confirm these findings.

Cost-effectiveness of edaravone dexborneol versus dl-3-n-butylphthalide for the treatment of acute ischemic stroke: a Chinese health care perspective

BACKGROUND

Edaravone dexborneol and dl-3-n-butylphthalide are two innovative brain cytoprotective drugs from China that have been approved and widely prescribed for acute ischemic stroke, and the cost of the two drugs are partially paid by the Chinese medical insurance system. This study aimed to investigate and compare the cost-effectiveness of edaravone dexborneol versus dl-3-n-butylphthalide for acute ischemic stroke from the Chinese healthcare system's perspective.

METHODS

A model combining a short-term decision tree model with 90 days and a long-term Markov model with a life-time horizon (40 years) was developed to simulate the cost-effectiveness of edaravone dexborneol versus dl-3-n-butylphthalide for acute ischemic stroke over a lifetime horizon. Since the absence of a head-to-head clinical comparison of two therapies, an unanchored matching-adjusted indirect comparison (MAIC) was conducted by adjusting the patient characteristics using individual patient data from pivotal phase III trial of edaravone dexborneol and published aggregated data of dl-3-n-butylphthalide. Health outcomes were measured in quality-adjusted life years (QALYs). Utilities and costs (Chinese Yuan, CNY) were derived from publications and open-access database. One-way and probabilistic sensitivity analyses were performed to evaluate the robustness of results.

RESULTS

Compared with patients in dl-3-n-butylphthalide arm, edaravone dexborneol arm was found to be cost-effective in 90 days and highly cost-effective as the study horizons extended. With a similar direct medical cost, patients in edaravone dexborneol arm slightly gained an additional 0.1615 QALYs in life-time. In the long term (40 years), patients in edaravone dexborneol arm and dl-3-n-butylphthalide arm yielded 8.0351 and 7.8736 QALYs with the overall direct medical cost of CNY 29,185.23 and CNY 29,940.28, respectively. The one-way sensitivity analysis suggested that the incremental cost-effectiveness ratio was most sensitive to the price of edaravone dexborneol and dl-3-n-butylphthalide.

CONCLUSION

Edaravone dexborneol is a cost-effective alternative compared with dl-3-n-butylphthalide for acute ischemic stroke patients in current medical setting of China.

Real-world Management of CML: Outcomes and Treatment Patterns

PURPOSE OF REVIEW

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.

RECENT FINDINGS

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.

Genetic Landscape of Chronic Myeloid Leukemia and a Novel Targeted Drug for Overcoming Resistance

Tyrosine kinase inhibitors (TKIs) exemplify the success of molecular targeted therapy for chronic myeloid leukemia (CML). However, some patients do not respond to TKI therapy. Mutations in the kinase domain of BCR::ABL1 are the most extensively studied mechanism of TKI resistance in CML, but BCR::ABL1-independent mechanisms are involved in some cases. There are two known types of mechanisms that contribute to resistance: mutations in known cancer-related genes; and Philadelphia-associated rearrangements, a novel mechanism of genomic heterogeneity that occurs at the time of the Philadelphia chromosome formation. Most chronic-phase and accelerated-phase CML patients who were treated with the third-generation TKI for drug resistance harbored one or more cancer gene mutations. Cancer gene mutations and additional chromosomal abnormalities were found to be independently associated with progression-free survival. The novel agent asciminib specifically inhibits the ABL myristoyl pocket (STAMP) and shows better efficacy and less toxicity than other TKIs due to its high target specificity. In the future, pooled analyses of various studies should address whether additional genetic analyses could guide risk-adapted therapy and lead to a final cure for CML.