Specific Tyrosine Kinase Inhibitor Research Articles

Cost-Effectiveness of Zanubrutinib Versus Bendamustine and Rituximab in Patients With Untreated Chronic Lymphocytic Leukemia

Zanubrutinib, a potent and specific irreversible Bruton's tyrosine kinase inhibitor, has proven to be effective in untreated chronic lymphocytic leukemia (CLL), whether used alone or in combination with other therapies. Here, we compared the cost-effectiveness of zanubrutinib with bendamustine-rituximab (R-bendamustine) to determine its effectiveness as the first-line treatment for Chinese patients with untreated CLL. The evaluation utilized a partitioned survival model, constructed using TreeAge Pro 2011 software, incorporating data from SEQUOIA trial (NCT03336333). Transition probabilities were estimated from the reported survival probabilities in trials using parametric survival modeling. In this analysis, the quality-adjusted life years (QALYs), incremental cost-effectiveness ratio, and lifetime cost were calculated from the Chinese health care system perspective. Sensitivity analyses, including 1-way analysis and probabilistic sensitivity analysis, were carried out to explore the uncertainty of the modeling results. Additionally, several scenario analyses, including different zanubrutinib price calculation and 20-year time horizon, were evaluated. The findings revealed that zanubrutinib had an incremental cost-effectiveness ratio of $58,258.18 per additional QALYs gained compared with bendamustine-rituximab, with zanubrutinib being cost-effective only if its price was reduced by more than 30%. Research indicated that zanubrutinib achieved at least a 3.70% probability of cost-effectiveness at the threshold of $38,223.34/QALY. One-way sensitivity analysis revealed that the results were sensitive to the utility of progressed disease. The study highlighted the importance of considering the cost-effectiveness of zanubrutinib at its current price point for patients with untreated CLL in China, emphasizing the need for further assessment and potential pricing adjustments to enhance its economic viability in clinical practice.

Lipopolymer/siRNA complexes engineered for optimal molecular and functional response with chemotherapy in FLT3-mutated acute myeloid leukemia

Approximately 25% of newly diagnosed AML patients display an internal tandem duplication (ITD) in the fms-like tyrosine kinase 3 (FLT3) gene. Although both multi-targeted and FLT3 specific tyrosine kinase inhibitors (TKIs) are being utilized for clinical therapy, drug resistance, short remission periods, and high relapse rates are challenges that still need to be tackled. RNA interference (RNAi), mediated by short interfering RNA (siRNA), presents a mechanistically distinct therapeutic platform with the potential of personalization due to its gene sequence-driven mechanism of action. This study explored the use of a non-viral approach for delivery of FLT3 siRNA (siFLT3) in FLT3-ITD positive AML cell lines and primary cells as well as the feasibility of combining this treatment with drugs currently used in the clinic. Treatment of AML cell lines with FLT3 siRNA nanocomplexes resulted in prominent reduction in cell proliferation rates and induction of apoptosis. Quantitative analysis of relative mRNA transcript levels revealed downregulation of the FLT3 gene, which was accompanied by a similar decline in FLT3 protein levels. Moreover, an impact on leukemic stem cells was observed in a small pool of primary AML samples through significantly reduced colony numbers. An absence of a molecular response post-treatment with lipopolymer/siFLT3 complexes in peripheral blood mononuclear cells, obtained from healthy individuals, denoted a passive selectivity of the complexes towards malignant cells. The effect of combining lipopolymer/siFLT3 complexes with daunorubucin and FLT3 targeting TKI gilteritinib led to a significant augmentation of anti-leukemic activity. These findings demonstrate the promising potential of RNAi implemented with lipopolymer complexes for AML molecular therapy. The study prospectively supports the addition of RNAi therapy to current treatment modalities available to target the heterogeneity prevalent in AML. Statement of significanceWe show that a clinically validated target, the FLT3 gene, can be eradicated in leukemia cells using non-viral RNAi. We validated these lipopolymers as effective vehicles to deliver nucleic acids to leukemic cells. The potency of the lipopolymers was superior to that of the ‘gold-standard’ delivery agent, lipid nanoparticles (LNPs), which are not effective in leukemia cells at clinically relevant doses. Mechanistic studies were undertaken to probe structure-function relationships for effective biomaterial formulations. Cellular and molecular responses to siRNA treatment have been characterized in cell models, including leukemia patient-derived cells. The use of the siRNA therapy with clinically used chemotherapy was demonstrated.

A bispecific antibody targeting EGFR and AXL delays resistance to osimertinib

Activating EGFR (epidermal growth factor receptor) mutations can be inhibited by specific tyrosine kinase inhibitors (TKIs), which have changed the landscape of lung cancer therapy. However, due to secondary mutations and bypass receptors, such as AXL (AXL receptor tyrosine kinase), drug resistance eventually emerges in most patients treated with the first-, second-, or third-generation TKIs (e.g., osimertinib). To inhibit AXL and resistance to osimertinib, we compare two anti-AXL drugs, an antibody (mAb654) and a TKI (bemcentinib). While no pair of osimertinib and an anti-AXL drug is able to prevent relapses, triplets combining osimertinib, cetuximab (an anti-EGFR antibody), and either anti-AXL drug are initially effective. However, longer monitoring uncovers superiority of the mAb654-containing triplet, possibly due to induction of receptor endocytosis, activation of immune mechanisms, or disabling intrinsic mutators. Hence, we constructed a bispecific antibody that engages both AXL and EGFR. When combined with osimertinib, the bispecific antibody consistently inhibits tumor relapses, which warrants clinical trials.

Toxicity of immune checkpoint inhibitors and tyrosine kinase inhibitor combinations in solid tumours: a systematic review and meta-analysis.

https://www.crd.york.ac.uk/prospero/, identifier CRD42022367416.

Resistance mechanisms of EGFR tyrosine kinase inhibitors, in EGFR exon 20 insertion-mutant lung cancer

BackgroundMobocertinib, an EGFR exon 20 insertion (Ex20ins)–specific tyrosine kinase inhibitor has been used for treatment of advanced/metastatic EGFR Ex20ins-mutant non-small cell lung cancer (NSCLC). However, resistance mechanisms to EGFR Ex20ins-specific inhibitors and the efficacy of subsequent amivantamab treatment is unknown. MethodsTo investigate resistance mechanisms, tissue and cfDNA samples were collected before treatment initiation and upon development of resistance from NSCLC patients with EGFR Ex20ins mutations received mobocertinib, poziotinib, and amivantamab treatments. Genetic alterations were analyzed using whole-genome and targeted sequencing, and in vitro resistant cell lines were generated for validation. ResultsEGFR amplification (n = 6, including 2 broad copy number gain) and EGFR secondary mutation (n = 3) were observed at the resistance of mobocertinib. One patient had both EGFR secondary mutation and high EGFR focal amplification. In vitro models harboring EGFR alterations were constructed to validate resistance mechanisms and identify overcoming strategies to resistance. Acquired EGFR-dependent alterations were found to mediate resistance to mobocertinib in patients and in vitro models. Furthermore, two of six patients who received sequential amivantamab followed by an EGFR tyrosine kinase inhibitor had MET amplification and showed partial response. ConclusionsOur study revealed EGFR-dependent and -independent mechanisms of mobocertinib resistance in patients with advanced EGFR Ex20ins-mutant NSCLC.

Epidermal Growth Factor Receptor Targeting in Colorectal Carcinoma: Antibodies and Patient-Derived Organoids as a Smart Model to Study Therapy Resistance.

Colorectal cancer (CRC) is the second leading cause of cancer-related death worldwide. Therefore, the need for new therapeutic strategies is still a challenge. Surgery and chemotherapy represent the first-line interventions; nevertheless, the prognosis for metastatic CRC (mCRC) patients remains unacceptable. An important step towards targeted therapy came from the inhibition of the epidermal growth factor receptor (EGFR) pathway, by the anti-EGFR antibody, Cetuximab, or by specific tyrosine kinase inhibitors (TKI). Cetuximab, a mouse-human chimeric monoclonal antibody (mAb), binds to the extracellular domain of EGFR thus impairing EGFR-mediated signaling and reducing cell proliferation. TKI can affect the EGFR biochemical pathway at different steps along the signaling cascade. Apart from Cetuximab, other anti-EGFR mAbs have been developed, such as Panitumumab. Both antibodies have been approved for the treatment of KRAS-NRAS wild type mCRC, alone or in combination with chemotherapy. These antibodies display strong differences in activating the host immune system against CRC, due to their different immunoglobulin isotypes. Although anti-EGFR antibodies are efficient, drug resistance occurs with high frequency. Resistant tumor cell populations can either already be present before therapy or develop later by biochemical adaptations or new genomic mutations in the EGFR pathway. Numerous efforts have been made to improve the efficacy of the anti-EGFR mAbs or to find new agents that are able to block downstream EGFR signaling cascade molecules. Indeed, we examined the importance of analyzing the anti-EGFR antibody-drug conjugates (ADC) developed to overcome resistance and/or stimulate the tumor host's immunity against CRC growth. Also, patient-derived CRC organoid cultures represent a useful and feasible in vitro model to study tumor behavior and therapy response. Organoids can reflect tumor genetic heterogeneity found in the tissue of origin, representing a unique tool for personalized medicine. Thus, CRC-derived organoid cultures are a smart model for studying the tumor microenvironment and for the preclinical assay of anti-EGFR drugs.

Development of a Bioanalytical Assay for the Selective RET Inhibitor Pralsetinib in Plasma Samples Utilizing Liquid Chromatography-Tandem Mass Spectrometry

Pralsetinib is a potent and specific tyrosine kinase inhibitor targeting the RET receptor, used in treating various cancers. This study developed and validated a bioanalytical assay for pralsetinib in plasma using liquid chromatography-tandem mass spectrometry (LC-MS/MS). The internal standard was erlotinib, and protein precipitation with acetonitrile was used for sample preparation. The analytes were separated on an Ultimate® XB-C18 column using gradient elution with ammonium acetate in water and methanol. Both are acidified with 0.1% formic acid. Detection was performed using positive electrospray ionization in the chosen reaction monitoring mode. The assay was validated over a linear range of 2 to 2000 ng/mL, achieving accuracies greater than 90% and precision values below 2%. The method was stable under all tested conditions without significant matrix effects or extraction losses.

STAT3 Pathways Contribute to β-HCH Interference with Anticancer Tyrosine Kinase Inhibitors.

Organochlorine pesticides (OCPs) are a class of environmentally persistent and bioaccumulative pollutants. Among these, β-hexachlorocyclohexane (β-HCH) is a byproduct of lindane synthesis, one of the most worldwide widespread pesticides. β-HCH cellular mechanisms inducing chemical carcinogenesis correspond to many of those inducing chemoresistance, in particular, by the activation of signal transducer and activator of transcription 3 (STAT3) signaling pathways. For this purpose, four cell lines, representative of breast, lung, prostate, and hepatocellular cancers, were treated with β-HCH, specific tyrosine kinase inhibitors (TKIs), and a STAT3 inhibitor. All cell samples were analyzed by a viability assay, immunoblotting analysis, a wound-healing assay, and a colony formation assay. The results show that β-HCH reduces the efficacy of TKIs. The STAT3 protein, in this context, plays a central role. In fact, by inhibiting its activity, the efficacy of the anticancer drug is restored. Furthermore, this manuscript aimed to draw the attention of the scientific and socio-healthcare community to the issue of prolonged exposure to contaminants and their impact on drug efficacy.

Kinome reprogramming as a therapeutic opportunity in ESR1 fusion driven breast cancer but not in gynecologic cancers.

1045 Background: The administration of specific tyrosine-kinase inhibitors in kinase fusion positive cancers has led to significant improvement in clinical outcomes. Gene fusions involving the ESR1 gene, a non-kinase, have been previously reported in breast and gynecologic cancers including ovarian cancer and uterine cancer. However, ERa inhibitors proved to be ineffective in ESR1 fusion positive cases, we have effectively characterized ESR1 fusions and hypothesized a surrogate downstream target as an effective approach to target ESR1 fusion positive breast cancer. Methods: We retrospectively analyzed 216,176 samples submitted for clinical molecular profiling at Caris Life Sciences via Caris MI Tumor Seek (Phoenix, AZ). Gene fusion detection was performed on mRNA isolated from a FFPE tumor sample using the Illumina NovaSeq platform. All ESR1 fusions with ≥ 3 junction reads were identified for manual review and for domain prediction, breakpoints, frame retention and co-occurring alterations by NGS. WES data was also investigated to evaluate co-occurring pathogenic mutations to establish the oncogenicity of gene fusions. Results: ESR1 fusions had the highest frequency in gynecologic and breast cancer. We evaluated ESR1 expression in cases with ESR1 fusions detected and observed higher expression of ESR1 in breast cancer, ovarian cancer (P<0.0001) and uterine cancer (P<0.0001) compared to respective cancer cases as determined by TPM values. The Kaplan-Meier curve also indicated poor prognosis for breast cancer patients with ESR1 fusions (619 days [n=105]) as opposed to patients who did not harbor any ESR1 variants (1396 days [n=755]; P<0.0001). Further, pathway analysis was performed on breast cancer ESR1 fusion positive and negative cases to discern specific downstream markers that might be upregulated. It was observed that RET(p<0.0001), IGF1R(p=0.0001) and FGFR3 (p<0.0001) were upregulated in ESR1 fusion positive breast cancer cases which may be largely determined by the TP53-FOXA1-ER alpha transcriptional axis. However, no significant increase of RET, IGF1R and FGFR3 was observed in gynecologic cancers, owing to high TP53 mutation frequency observed in ovarian cancer (90%) and uterine cancer (82%) compared to breast cancer(19%). Conclusions: We highlight that ESR1 fusions can be reliably detected in patients with breast cancer, ovarian cancer, and endometrial cancers. ESR1 fusions lose the ligand binding domain and cannot be targeted using current estrogen modulators or degraders. We have discovered the upregulation of oncogenic kinase signaling in ESR1 fusion positive breast cancer, but not in gynecologic cancers. Our observations highlight enhanced oncogenic kinase signaling as a surrogate approach with clinically approved kinase inhibitors for targeting ESR1 fusion positive breast cancer cases but not in ovarian and uterine cancers.

Abstract 952: Ex vivo drug testing identifies a potentially effective drug in 94% of cases for 403 patients in 42 tumor types

Abstract Objective: To determine whether patient derived tumor cells (PDTC) could be derived from a variety of solid tumors and used to select effective therapies, we developed a CLIA certified assay, the PARIS® test, to quantify drug sensitivities using PDTCs. Methods: Oncologists referred patients for the PARIS® test and patients had the option to consent to SEngine Precision Medicine’s IRB protocol. Samples were obtained from multiple cancer centers across the US and abroad. Patients were at all stages in their clinical journey ranging from treatment naïve to late stage, recurrent/refractory disease settings. Fresh specimens obtained from surgical resections, core biopsies, or body fluids arrived at our CLIA laboratory within 48 hrs from collection. Tumor origin and driver mutations were confirmed by IHC or DNA sequence in 88% of the cases. Results: PDTCs derived from 403 patients diagnosed with 42 different solid tumor types, including both common and rare tumors, were subjected to the PARIS® assay. An average of 67 oncology drugs (ranging from 6-307), including chemotherapies and targeted agents, were tested for each patient sample. A report ranking drug sensitivities was provided to the oncologist with an average turnaround time of less than 3 weeks. Drug sensitivity was classified as exceptional/good, moderate/low and no responses. Remarkably, 94.2% of the PDTCs exhibited selective exceptional/good responses to at least one, and typically several drugs, despite the majority of PDTCs being derived from patients with drug resistant, metastatic disease. The drug sensitivity profiles showed highly individualized responses as well as tumor type specificity. While known biomarkers/drug sensitivity associations were confirmed, many samples exhibited sensitivity to targeted agents in the absence of known biomarkers. For example, HER2+ breast cancers demonstrated sensitivity to HER2/EGFR inhibitor and a subset of luminal B and triple negative breast cancers demonstrated HER2/EGFRi responses without underlying genetic alterations. Functional testing was also useful in the rare tumor types. For example, low grade serous ovarian cancer (LGSOC) cells, differentiated from high grade by their response to specific receptor tyrosine kinase inhibitors and estrogen antagonists, but a poor response to standard of care, as is observed in the clinic. Three patients with LGSOC that were treated with the PARIS test top scoring drugs had a positive clinical response and cases from other tumor types will be presented. Conclusions: Functional testing of PDTCs from both common and rare tumor types is feasible, even for those that have failed standard of care. We provide an unprecedented view of patient-specific, actionable vulnerabilities to current oncology drugs. Personalization of cancer care will require improved access to off-label drugs. Citation Format: Rachele Rosati, Alex C. Rajevski, Payel Chatterjee, Lauren R. Appleyard, Ana Cristina Cordero Schmidt, Shalini Pereira, Robert L. Diaz, Brady Bernard, Brady Bernard, Carla Grandori, Christopher J. Kemp. Ex vivo drug testing identifies a potentially effective drug in 94% of cases for 403 patients in 42 tumor types [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 952.

Comparing the Efficacy of Two Generations of EGFR-TKIs: An Integrated Drug-Disease Mechanistic Model Approach in EGFR-Mutated Lung Adenocarcinoma.

Mutationsin epidermal growth factor receptor (EGFR) are found in approximately 48% of Asian and 19% of Western patients with lung adenocarcinoma (LUAD), leading to aggressive tumor growth. While tyrosine kinase inhibitors (TKIs) like gefitinib and osimertinib target this mutation, treatments often face challenges such as metastasis and resistance. To address this, we developed physiologically based pharmacokinetic (PBPK) models for both drugs, simulating their distribution within the primary tumor and metastases following oral administration. These models, combined with a mechanistic knowledge-based disease model of EGFR-mutated LUAD, allow us to predict the tumor's behavior under treatment considering the diversity within the tumor cells due to different mutations. The combined model reproduces the drugs' distribution within the body, as well as the effects of both gefitinib and osimertinib on EGFR-activation-induced signaling pathways. In addition, the disease model encapsulates the heterogeneity within the tumor through the representation of various subclones. Each subclone is characterized by unique mutation profiles, allowing the model to accurately reproduce clinical outcomes, including patients' progression, aligning with RECIST criteria guidelines (version 1.1). Datasets used for calibration came from NEJ002 and FLAURA clinical trials. The quality of the fit was ensured with rigorous visual predictive checks and statistical tests (comparison metrics computed from bootstrapped, weighted log-rank tests: 98.4% (NEJ002) and 99.9% (FLAURA) similarity). In addition, the model was able to predict outcomes from an independent retrospective study comparing gefitinib and osimertinib which had not been used within the model development phase. This output validation underscores mechanistic models' potential in guiding future clinical trials by comparing treatment efficacies and identifying patients who would benefit most from specific TKIs. Our work is a step towards the design of a powerful tool enhancing personalized treatment in LUAD. It could support treatment strategy evaluations and potentially reduce trial sizes, promising more efficient and targeted therapeutic approaches. Following its consecutive prospective validations with the FLAURA2 and MARIPOSA trials (validation metrics computed from bootstrapped, weighted log-rank tests: 94.0% and 98.1%, respectively), the model could be used to generate a synthetic control arm.

Regulation of Cell Cycle Progression through RB Phosphorylation by Nilotinib and AT-9283 in Human Melanoma A375P Cells.

BCR-ABL tyrosine kinase inhibitors are commonly employed for the treatment of chronic myeloid leukemia, yet their impact on human malignant melanoma remains uncertain. In this study, we delved into the underlying mechanisms of specific BCR-ABL tyrosine kinase inhibitors (imatinib, nilotinib, ZM-306416, and AT-9283) in human melanoma A375P cells. We first evaluated the influence of these inhibitors on cell growth using cell proliferation and wound-healing assays. Subsequently, we scrutinized cell cycle regulation in drug-treated A375P cells using flow cytometry and Western blot assays. Notably, imatinib, nilotinib, ZM-306416, and AT-9283 significantly reduced cell proliferation and migration in A375P cells. In particular, nilotinib and AT-9283 impeded the G1/S transition of the cell cycle by down-regulating cell cycle-associated proteins, including cyclin E, cyclin A, and CDK2. Moreover, these inhibitors reduced RB phosphorylation, subsequently inhibiting E2F transcriptional activity. Consequently, the expression of the E2F target genes (CCNA2, CCNE1, POLA1, and TK-1) was markedly suppressed in nilotinib and AT9283-treated A375P cells. In summary, our findings suggest that BCR-ABL tyrosine kinase inhibitors may regulate the G1-to-S transition in human melanoma A375P cells by modulating the RB-E2F complex.

BCR/ABL-Positive Chronic Myeloid Leukemia in Children: Current Treatment Approach.

The purpose of this review is to summarize the most updated treatment recommendations for pediatric CML, and to discuss current areas of investigation. There is new phase 1 data to support the safety of the non-ATP competitive tyrosine kinase inhibitor (TKI) asciminib in the pediatric cohort. Ongoing studies are investigating the role of treatment-free remission in children. Chronic phase CML in children is managed with lifelong TKI therapy; however, evidence of deeper remissions sustained with second-generation TKIs may permit shorter treatment courses. Use of more specific TKIs may mitigate some of the side effects specific to the pediatric cohort. Children with advanced phase CML should achieve a complete hematologic remission with use of a second-generation TKI prior to transplant to achieve the best outcome.

Beyond BCR::ABL1-The Role of Genomic Analyses in the Management of CML.

Chronic myeloid leukemia (CML) is a model of genomically based diagnosis and management where BCR::ABL1 is successfully targeted by tyrosine kinase inhibitor (TKI) therapy in most patients. The dynamics of BCR::ABL1 transcript decline during therapy is a dependable biomarker of response, relapse, and drug resistance. Missense mutations acquired within the BCR::ABL1 kinase domain that disrupt TKI binding can evolve during therapy and are frequently detected in patients for whom TKI treatment fails. Importantly, specific BCR::ABL1 missense mutations are targetable alterations and direct therapeutic decisions based on the individual mutant TKI sensitivity profile. Nevertheless, BCR::ABL1 mutations are only implicated in approximately half of the cases of acquired resistance. Furthermore, not all patients with a single BCR::ABL1 mutation that is predicted to be sensitive to a specific TKI will experience a response when switched to that TKI. Progression to blast phase heralds independence from BCR::ABL1, and this phase of the disease is notoriously difficult to treat. The independent drivers of resistance and disease progression have long been investigated to both predict progression and to find targets for therapeutic intervention. Recent data reaffirm that drug resistance and disease progression is a mutation-driven process in CML, and somatic variants in genes that are known to drive acute myeloid and lymphoid leukemia have been detected in patients in the advanced phases of CML. Genomic testing over the last few decades for patients with blood cancer has revealed of variety of genomic aberrations that drive disease. Consequently, incorporation of genomic factors into patient management for a range of blood cancers has led to the implementation of high-throughput gene testing to detect clinically actionable variants. Is it time to integrate broader genomic screening into clinical management strategies for patients with CML?

Prognostic Impact of Bone Marrow Fibrosis and Effects of Tyrosine Kinase Inhibitors on Bone Marrow Fibrosis in Chronic Myeloid Leukemia

BackgroundMyelofibrosis is reported in around 40% of newly diagnosed chronic myeloid leukemia (CML) patients and have an important role in the pathobiology and prognosis of CML. This retrospective study aimed to evaluate the effects of bone marrow (BM) fibrosis on disease prognosis and the effects of specific tyrosine-kinase inhibitors (TKIs) on BM fibrosis in CML patients. MethodsThe study included 96 patients (>18 years) diagnosed with chronic phase (CP) CML. The clinical and demographic information were collected from the medical files. Post-treatment BM aspirate and core biopsy samples were analyzed for the presence of fibrosis and dysplasia. ResultsThe mean age of the study patients was 52.69 years; 47.9% of the patients were female. At the onset, 53 (63.1%) patients had BM fibrosis. The difference in the overall survival of the patients with respect to BM fibrosis grades was significant (p = .001). Within the BM fibrosis grade groups, there were significant differences between grade 0 vs. grade 2, grade 0 vs. grade 3, and grade 1 vs. grade 3 (p = .005, p = .002, and p = .003 respectively) There was no significant association between the presence of BM fibrosis at the onset and not responding to first-line therapy (p = .724). Moreover, no significant association was found between the presence of BM fibrosis at the onset and molecular (p = .623) or cytogenetic response (p = .535) to first-line therapy. Additionally, the association between the type of second-line and third-line therapy and molecular response (p = .773 and p = .424, respectively) or cytogenetic response (p = .298 and p = .641) was not significant. ConclusionAlthough BM fibrosis seems to be a crucial complication of CML with a poor prognosis, it can be reversed via TKI treatment which may result in improved survival. It might be considered to check the BM for this complication on a regular basis during therapies to test its prognostic influence in CML patients in prospective controlled trials. Further studies focused on this issue are required to utilize BM fibrosis as a candidate prognostic factor.

The importance of re-biopsy in the era of molecular therapy for lung cancer

Introduction. Recent epidemiological data highlight that lung cancer incidence and mortality rates remain alarmingly high globally for both men and women. Over the last 10 years, the evolution in treatment corresponds to identifying specific driver mutations within lung tumors and developing inhibitors targeting these mutations. Case outline. A 73-year-old woman was diagnosed with lung adenocarcinoma staged as T4N2M1b at the Institute for Pulmonary Diseases of Vojvodina in February 2019. The Oncology Board recommended molecular analysis of the tumor and palliative radiation therapy for spinal metastases. Molecular testing identified an exon 19 deletion in the epidermal growth factor receptor (EGFR) gene. Following radiation treatment of the spine metastases, the patient began treatment with afatinib in May 2019. After 35 cycles of the aforementioned therapy, in April 2022, a computed tomography scan of the thorax and abdomen showed that the disease had progressed. Despite three liquid biopsies failing to detect the T790M mutation, a subsequent bronchoscopy and tissue re-biopsy confirmed its presence, prompting the initiation of osimertinib treatment. Twelve months into osimertinib therapy, the patient continues to be monitored. Conclusion. EGFR is a crucial predictive biomarker for non-small cell lung cancer. The introduction of specific tyrosine kinase inhibitors ? first-generation agents like gefitinib and erlotinib, second-generation afatinib, and introduction of third-generation (osimertinib or lolatinib) when initial treatments are met with resistance, has led to significant therapeutic breakthroughs.

MiR-181a plays the tumor-suppressor role in chronic myeloid leukemia CD34 + cells partially via SERPINE1

The formation of the BCR-ABL fusion gene drives human chronic myeloid leukemia (CML). The last 2 decades have witnessed that specific tyrosine kinase inhibitors (TKIs, e.g., imatinib mesylate, IM) against ABL1 improve disease treatment, although some patients still suffer from relapse and TKI resistance. Therefore, a better understanding of the molecular pathology of CML is still urgently needed. miR-181a-5p (miR-181a) acts as a tumor suppressor in CML; however, the molecular mechanism of miR-181a in CML stem/progenitor cells remains elusive. Herein, we showed that miR-181a inhibited the growth of CML CD34+ cells, including the quiescent subset, and sensitized them to IM treatment, while miR-181a inhibition by a sponge sequence collaborated with BCR-ABL to enhance the growth of normal CD34+ cells. Transcriptome data and biochemical analysis revealed that SERPINE1 was a bona fide and critical target of miR-181a, which deepened the understanding of the regulatory mechanism of SERPINE1. Genetic and pharmacological inhibition of SERPINE1 led to apoptosis mainly mediated by caspase-9 activation. The dual inhibition of SERPINE1 and BCR-ABL exhibited a significantly stronger inhibitory effect than a single agent. Taken together, this study demonstrates that a novel miR-181a/SERPINE1 axis modulates CML stem/progenitor cells, which likely provides an important approach to override TKI resistance.

HJKC3-007: Outcomes of Patients with Chronic Myeloid Leukemia in Chronic Phase Treated with Asciminib and Other Tyrosine Kinase Inhibitors in Routine Clinical Practice

Background and significance: There are typically high response rates to first line TKI therapies in chronic phase chronic myeloid leukemia (CP-CML). However, responses in later lines (second line and beyond) are diminished and highly dependent on the specific tyrosine kinase inhibitors (TKIs) used. Asciminib received FDA approval in October 2021 for the treatment of adult patients with Philadelphia chromosome-positive (Ph+) CML-CP who were previously treated with two or more TKIs, and in patients with Ph+ CML-CP with the T315I mutation. Our goal in this study is to evaluate the role of asciminib therapy for patients with CML beyond clinical studies, in routine clinical practice. Study Design and methods: Data for this study will be abstracted from the HJKC3 (H. Jean Khoury Cure CML Consortium) CML registry project (HJKC3-0005); the HJKC3 CML Registry is a collaborative academic multi-site registry. Patients will be consented to allow collection of both retrospective and prospective data for the HJKC3 CML Registry. The data forms and surveys will be built and managed through the Research Electronic Data Capture (REDCap), a secure web application managed by the Clinical & Translational Science Institute. Participating sites include members of the HJKC3 (curecml.org). This study will be an opportunity to evaluate asciminib usage in ‘real-world’ academic practices across the United States. This observational study will include cohorts of patients diagnosed with CP-CML previously treated with two or more tyrosine kinase inhibitors and/or receiving asciminib and/or those with a T315I mutation, not currently enrolled in a randomized controlled trial. The HJKC3 CML Registry intends to collect clinical and patient reported outcome (PRO) data. After obtaining patient consent, patients will be invited to complete PRO assessments. The study will attempt to collect PRO data regardless of disease or treatment status. PRO assessments will be primarily administered online, though study staff will offer alternatives (e.g., phone) for participants without internet access. Study subjects will be emailed a link to access a secure platform hosted by one of the study sites, Medical College of Wisconsin (MCW), using the REDCap platform. Study Objectives: The primary objective of the study is to describe characteristics of patients who were previously treated with two or more TKIs and treated with asciminib or with any other TKIs. The secondary objectives are to describe the clinical outcomes and PRO of those patients. Exploratory objectives include description of characteristics, treatment outcome and PRO for patients with T315I mutation. Statistical plan: The sample size of approximately 225 participants during the 5-year recruitment period is based on the available clinical expertise and ongoing recruitment data in the HJKC3 CML registry in lieu of statistical power analysis. We estimate that 150 patients in the HJKC3 CML registry will be treated with other TKI and 75 treated with asciminib. Among a total of 225 patients, we estimate that 75 patients with the T315I mutation will be enrolled in the registry. No formal statistical inference will be drawn to compare the outcomes between these two groups. Bayesian predictive probability (PP) will be utilized for the exploratory analysis of Major Molecular Response (MMR). Survival probabilities will be computed using the Kaplan-Meier method, and the p-values from the log-rank test will be provided. Different PRO domains of the patient's symptoms and functioning will be analyzed separately (e.g., depression separate from fatigue, separate from GI symptoms, etc.) since combining them into a summary score may dilute the effects of the individual (and not necessarily related) components and mask actual change. The main objective for the analyses of PRO data from the registry is to describe any differences by treatment type in patients treated with asciminib and other TKIs.

HJKC3-0006: Outcome of Patients with CML Treated on Second Line or Later Therapy in Routine Clinical Practice

Background: First-line therapies for chronic-phase (CP) CML include the tyrosine kinase inhibitors(TKIs) dasatinib, nilotinib, bosutinib or imatinib, while ponatinib and asciminib are indicated only in later lines. There are typically high response rates to first-line therapy in CP-CML, with responses to second- and third-line therapy lower and highly dependent on the specific TKI. Our goal in this study is to evaluate the role of ponatinib in the treatment of patients with CML using data from routine clinical practice. Study design and methods: Data will come from the H. Jean Khoury Cure CML Consortium (HJKC3) CML registry, a North American multi-site research database. Participating sites include the HJKC3 members (curecml.org). Patient inclusion criteria include a diagnosis CML in chronic phase, receiving second line therapy after initial therapy with a second generation TKI (dasatinib, nilotinib, or bosutinib) or receiving third or later line TKI therapy for CML. Participating patients provide consent to collect their data both retrospectively and prospectively for 1 year. Clinical data, including toxicities and complications of TKI therapy, are abstracted from the electronic health record. Participating patients are invited to complete a questionnaire to assess health-related quality of life. Data are managed using REDCap, a secure web application. Study Objectives: The primary objective is to compare the outcome of patients treated with ponatinib vs. other TKIs as second or later line therapy. Secondary objectives are to evaluate patient-reported outcomes (PRO) for CML treated with second or later line therapy and to determine if there are any patient or disease characteristics that can predict outcomes. Statistical plan for clinical outcomes: Descriptive statistics will be used to compare baseline demographic characteristics. Categorical variables will be compared using the Chi-square test. Continuous variables will be compared using ANOVA. Overall survival will be calculated from the time of diagnosis to death from any cause and patients will be censored if they were alive at the last follow-up. Survival probabilities will be computed using the Kaplan-Meier method and compared with the log-ranktest. Cox regression analyses will be used to determine significant factors that influence survival, and hazard ratios with 95% confidence intervals will be presented. Event free survival (EFS) and transformation free survival (TFS) will be calculated for patients. For EFS, loss of complete hematologic remission, loss of major cytogenetic response, progression to accelerated or blast phase, or death from any cause at any time will be considered an event. For TFS, transformation to accelerated or blast phase while on therapy or death on study will be considered an event. Statistical plan for PRO: Different PRO domains will be analyzed separately (for example, depression separate from fatigue, etc.). Descriptive statistics for each PRO measure will be reported and compared to previously published studies. Differences by treatment type will be evaluated.

Zanubrutinib vs FCR in Fit Treatment-Naive Patients with Chronic Lymphocytic Leukemia: A Matching-Adjusted Indirect Comparison

Background: Fludarabine, cyclophosphamide, and rituximab (FCR) is the standard first-line therapy for fit (physically active, with no major health problems and normal renal function) treatment-naive patients with chronic lymphocytic leukemia (CLL) (Eichhorst et al. Ann Oncol. 2015). Due to the safety profile of FCR, including severe hematotoxicity, and severe infections, treatments with improved efficacy and safety are of interest (Hallek et al. Lancet. 2010; Fischer et al. Blood. 2016). Zanubrutinib, a highly specific and potent small-molecule inhibitor of Bruton tyrosine kinase, has been approved for treatment-naive patients with CLL. However, the comparative efficacy of zanubrutinib vs FCR in patients with CLL has not been investigated. Objective: The objective of this study was to determine the relative treatment effects of zanubrutinib vs FCR in fit treatment-naive patients with CLL. Methods: The CLL10 trial (NCT00769522; Eichhorst et al. Lancet Oncol. 2016) investigated FCR and bendamustine + rituximab (BR), while the SEQUOIA trial compared zanubrutinib to BR (NCT03336333; Tam et al. Lancet Oncol. 2022). Zanubrutinib and FCR were compared by means of an anchored matching-adjusted indirect comparison (MAIC) in which the BR arm of each trial served as a common comparator. Propensity score matching was conducted using patient-level data from SEQUOIA to adjust for differences between trial populations, per National Institute for Health and Care Excellence MAIC methods (Philippo et al. NICE DSU Technical Support Document 18. 2016). Progression-free survival (PFS), as assessed by the independent review committee, was then compared based on the matched patient populations. The selection of matching variables was based on literature review and consultation with clinical experts. As the indirect treatment comparison was anchored on the common comparator arm (BR), patient characteristics that are solely prognostic did not need to be incorporated. The core model included immunoglobulin heavy chain gene mutation, cytogenetic mutations (11q deletion), β2-microglobulin, Binet stage, and age. Geographic region, sex, creatinine clearance, Cumulative Illness Rating Scale (CIRS) score, Eastern Cooperative Oncology Group performance status (ECOG PS), and previous infections were tested in sensitivity analyses. Results: PFS was favorable with zanubrutinib vs FCR, and statistically significant differences were observed in the base case model (hazard ratio [HR], 0.41; 95% CI, 0.20-0.81; p-value=0.01). Sensitivity analyses showed significantly improved PFS with zanubrutinib when adding geographic region (HR, 0.43; 95% CI, 0.21-0.90; p-value=0.03), sex (HR, 0.44; 95% CI, 0.22-0.89; p-value=0.02), ECOG PS (HR, 0.30; 95% CI, 0.14-0.64; p-value<0.01), and previous infections (HR, 0.45; 95% CI, 0.22-0.93; p-value=0.03) to the base case set of matching variables. A sensitivity analysis incorporating CIRS (HR, 0.45; 95% CI, 0.16-1.24; p-value=0.12) showed only numerically favorable PFS with zanubrutinib, owing in part to the low effective sample size (ESS) in the expanded model. Similar results were obtained when creatinine clearance was added to the base case matching set of variables (HR, 0.52; 95% CI, 0.24-1.13; p-value=0.10). Conditional on the number of matching variables, ESS ranged from 174.1 in the core model to 64.05 in the analysis that included the CIRS score. Conclusion:Our findings suggest that zanubrutinib offers clinically meaningful benefits in PFS over FCR in fit treatment-naive patients with CLL. MAICs rely on reporting of relevant patient characteristics in published studies. In the current study, ZAP-70 methylation and TP53 mutation, which were considered treatment effect modifiers, were not reported in CLL10 and were not accounted for in the propensity model.