Specific Tyrosine Kinase Inhibitor Research Articles

Future perspectives from lung cancer pre-clinical models: new treatments are coming?

Lung cancer currently stands out as both the most common and the most lethal type of cancer, the latter feature being partly explained by the fact that the majority of lung cancer patients already display advanced disease at the time of diagnosis. In recent years, the development of specific tyrosine kinase inhibitors (TKI) for the therapeutic benefit of patients harboring certain molecular aberrations and the introduction of prospective molecular profiling in the clinical practice have revolutionized the treatment of advanced non-small cell lung cancer (NSCLC). However, the identification of the best strategies to enhance treatment effectiveness and to avoid the critical phenomenon of drug tolerance and acquired resistance in patients with lung cancer still remains an unmet medical need. Circulating tumor cells (CTCs) and circulating tumor DNA (ctDNA) are two complementary approaches to define tumor heterogeneity and clonal evolution in a non-invasive manner and to perform functional studies on metastatic cells. Finally, the recent discovery that the tumor microenvironment architecture can be faithfully recapitulated in vitro represents a novel pre-clinical frontier with the potential to optimize more effective immunology-based precision therapies that could rapidly move forward to the clinic.

The regulation of bcr-abl in hypoxia is through the mTOR pathway

Chronic myeloid leukemia (CML) is usually characterized by the formation of the fusion onco-protein bcr-abl. Therefore, the majority of CML treatments are bcr-abl specific tyrosine kinase inhibitors (TKIs). TKI resistance in CML treatment is becoming a major obstacle in managing this disease. One well-studied form of drug resistance is hypoxia-induced drug resistance, a phenomenon observed in many other cancers. This study aimed to determine the efficacy of TKIs in CML cells cultured in hypoxia. It was observed that bcr-abl translation was severely halted in hypoxia, rendering TKIs ineffective. We found that the mechanism by which bcr-abl protein levels were being suppressed in hypoxia was through the mTOR pathway, specifically via ribosomal protein S6 (RPS6). This information is vital to the improvement of CML treatments, as it can be used to determine how to best combat hypoxia-induced drug resistance in CML and subsequently to identify new targets for treatment.

CTNI-02. TBCRC049: A PHASE II STUDY TO ASSESS THE SAFETY AND EFFICACY OF THE COMBINATION OF TUCATINIB, TRASTUZUMAB AND CAPECITABINE FOR THE TREATMENT OF LEPTOMENINGEAL METASTASIS IN HER2 POSITIVE BR1AST CANCER

Abstract Treatment options for patients with leptomeningeal metastasis (LM) from HER2-positive breast cancer (HER2+ BC) are limited and prognosis is poor. Tucatinib is an oral, potent, HER2 specific tyrosine kinase inhibitor with good tolerability and combinatory anti-tumor activity, including partial responses in heavily treated patients and those with brain metastases (BM). This is a phase 2 single-arm study to evaluate the efficacy of tucatinib, trastuzumab and capecitabine in HER2+ BC with newly-diagnosed LM. CNS disease will be evaluated at screening and every 6 weeks by neuroaxis MRI, CSF cytology, and neurological assessments per RANO-LMD (adapted) and RANO-BM criteria. Extra-CNS disease will be evaluated at screening and every 12 weeks by CT scan per RECIST criteria. All patients will be followed for survival. Symptom burden and quality of life assessments, as well as correlative blood and CSF samples, will be collected. Eligible patients include adults with HER2+ BC, KPS > 50, and newly-diagnosed, untreated LM (defined as positive CSF cytology and/or radiographic evidence of LM, plus clinical signs/symptoms). Patients with treated or concurrent/new BM are allowed. Patients treated with capecitabine within the last 12 months are excluded. This study has a Gehan-like design with an interim futility analysis and overall intent to estimate OS. For the interim analysis, success is defined as CNS PFS for 12 weeks. Enrollment will end if fewer than two successes are observed in the first 15 patients. Secondary endpoints include safety, CNS PFS at 12 weeks, RR in CNS and extra-CNS, and symptom burden/quality of life. The regimen will be considered worthy of future study if the median OS is > 4.4 months. Fourteen of 30 patients have accrued thus far. The study is active at multiple Translational Breast Cancer Research Consortium sites around the country.

Focus on ROS1-Positive Non-Small Cell Lung Cancer (NSCLC): Crizotinib, Resistance Mechanisms and the Newer Generation of Targeted Therapies.

Simple SummaryGenetic rearrangements of the ROS1 gene account for up to 2% of NSCLC patients who sometimes develop brain metastasis, resulting in poor prognosis. This review discusses the tyrosine kinase inhibitor crizotinib plus updates and preliminary results with the newer generation of tyrosine kinase inhibitors, which have been specifically conceived to overcome crizotinib resistance, including brigatinib, cabozantinib, ceritinib, entrectinib, lorlatinib and repotrectinib. After introducing each agent’s properties, we provide suggestions on the best approaches to identify resistance mechanisms at an early stage, and we speculate on the most appropriate second-line therapies for patients who reported disease progression following crizotinib administration.The treatment of patients affected by non-small cell lung cancer (NSCLC) has been revolutionised by the discovery of druggable mutations. ROS1 (c-ros oncogene) is one gene with druggable mutations in NSCLC. ROS1 is currently targeted by several specific tyrosine kinase inhibitors (TKIs), but only two of these, crizotinib and entrectinib, have received Food and Drug Administration (FDA) approval. Crizotinib is a low molecular weight, orally available TKI that inhibits ROS1, MET and ALK and is considered the gold standard first-line treatment with demonstrated significant activity for lung cancers harbouring ROS1 gene rearrangements. However, crizotinib resistance often occurs, making the treatment of ROS1-positive lung cancers more challenging. A great effort has been undertaken to identify a new generation or ROS1 inhibitors. In this review, we briefly introduce the biology and role of ROS1 in lung cancer and discuss the underlying acquired mechanisms of resistance to crizotinib and the promising new agents able to overcome resistance mechanisms and offer alternative efficient therapies.

Cardiovascular and Metabolic Risk in Patients with Chronic Myeloid Leukemia in Chronic Phase Receiving First-Line BCR-ABL1 Tyrosine Kinase Inhibitors in the United States: Baseline and Six-Month Follow-up Results from a Prospective Real-World Observational Study

Introduction: Tyrosine kinase inhibitors (TKIs) are the standard-of-care for patients with chronic myeloid leukemia in chronic phase (CML-CP) and are associated with improved outcomes. The risk of cardiovascular (CV) events has emerged as an important consideration during TKI therapy, mostly due to associated complications and the need to understand causality and proper mitigation. While nilotinib has been associated with an increased risk of CV events, few prospective studies have assessed the CV and metabolic risk profile of TKIs administered during routine clinical practice in a real-world setting. Importantly, data regarding the role of baseline CV risk factors at initiation of specific TKIs and subsequent CV events are limited. Here we assess CV and metabolic risk in patients with CML-CP undergoing first-line treatment with TKIs in a real-world setting. Methods: CA180-653 (NCT03045120) is an ongoing, non-interventional, prospective clinical trial characterizing the impact of approved TKIs (bosutinib, dasatinib, imatinib, and nilotinib) on CV and metabolic risk factors following initial TKI therapy in newly diagnosed patients with CML-CP in the USA. Baseline clinical and demographic characteristics, including medical history, vital signs, and evidence of additional comorbid conditions were assessed. CV and metabolic risk factors, as well as CV disease surrogates, were also measured, including ankle brachial index (ABI), echocardiogram (ECHO), electrocardiogram (EKG), and Framingham coronary heart disease score. Metabolic risk variables included fasting blood glucose, HbA1c, and fasting lipid panel. Enrolled patients were analyzed at both baseline and at six months after study enrollment. Results: Between March 2017 and December 2019, 109 patients were enrolled at 16 study sites across the USA. The analysis included patients treated with dasatinib (n = 48), imatinib (n = 47), and nilotinib (n = 14); key characteristics and CV findings are summarized in the Table. In all, 48.9% of patients prescribed imatinib were ≥ 65 years of age, compared with 22.9% of dasatinib and 28.6% of nilotinib patients. Patients treated with dasatinib had a marginally lower proportion of reported baseline CV/metabolic conditions (50.0%) compared to imatinib (53.2%) and nilotinib (57.1%). Interestingly, among patients with baseline Ca2+ scoring, 57.1% of nilotinib patients had coronary artery calcification present at baseline compared to 35.7% of imatinib patients and 28.9% of dasatinib patients. Most patients receiving an ECHO (96%) or EKG (99%) were assessed as normal or presenting clinically not significant abnormalities both at baseline and at the 6-month follow-up. Baseline corrected QT (QTC) scores were similar for dasatinib, imatinib, and nilotinib patients. Among patients with a change in QTC at six months, patients on imatinib had a larger change in median score (13.5 msec) than patients on nilotinib (8.0 msec) or dasatinib (2.0 msec). At six months, changes in ABI scores were small and unlikely to be statistically significant: left ABI scores changed by -0.030, -0.020, and 0.015 for patients on dasatinib, nilotinib, and imatinib respectively; right ABI scores changed by -0.030, 0.055, and 0.060 for patients on dasatinib, imatinib, and nilotinib, respectively. Additional longitudinal data will be presented. Conclusions: These preliminary findings confirm that just over half of patients with CML-CP in the USA have CV/metabolic comorbidities present at baseline, as measured by reproducible and sequentially evaluable studies known to be predictive of systemic vascular disease risk. Measurement of baseline clinical data is vital for assessing CV and metabolic risk in the US oncology settings. CA180-653 was powered to capture the impact of first- and second-generation TKIs on CV and metabolic risk factor outcomes within treatment arms, rather than between treatment arms. Further analysis is ongoing to determine the differential effects of TKIs used in CML-CP, the effect of long-term TKI therapy, and the value of specific CV evaluations to assess optimally and manage risk in patients with CML-CP. Study support:BMS. Table Disclosures Mauro: Sun Pharma/SPARC:Research Funding;Pfizer:Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding;Takeda:Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding;Novartis:Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding;Bristol-Myers Squibb:Consultancy, Honoraria, Other: Travel, Accommodation, Expenses, Research Funding.Oehler:Pfizer:Research Funding;Bristol-Myers Squibb, Takeda:Consultancy.McCloskey:Jazz:Consultancy, Honoraria;AbbVie:Consultancy, Honoraria;Takeda:Consultancy, Honoraria;BMS:Consultancy, Honoraria;Amgen:Consultancy, Honoraria.Heinrich:Novartis:Consultancy, Patents & Royalties: Patent on treatment of GIST licensed to Novartis;Blueprint Medicines:Consultancy;Deciphera:Consultancy, Speakers Bureau.DeGutis:Bristol-Myers Squibb:Current Employment, Current equity holder in publicly-traded company.Tabano:Bristol-Myers Squibb:Current Employment.Khan:Bristol-Myers Squibb:Current Employment, Current equity holder in publicly-traded company.Moslehi:AstraZeneca, Janssen, BMS, Boston Biomedical, Immunocure, Myovant, Boston Biomedical, Deciphera:Consultancy.

Ibrutinib-Mediated Atrial Fibrillation Attributable to Inhibition of C-Terminal Src Kinase.

Ibrutinib is a Bruton tyrosine kinase inhibitor with remarkable efficacy against B-cell cancers. Ibrutinib also increases the risk of atrial fibrillation (AF), which remains poorly understood. We performed electrophysiology studies on mice treated with ibrutinib to assess inducibility of AF. Chemoproteomic analysis of cardiac lysates identified candidate ibrutinib targets, which were further evaluated in genetic mouse models and additional pharmacological experiments. The pharmacovigilance database, VigiBase, was queried to determine whether drug inhibition of an identified candidate kinase was associated with increased reporting of AF. We demonstrate that treatment of mice with ibrutinib for 4 weeks results in inducible AF, left atrial enlargement, myocardial fibrosis, and inflammation. This effect was reproduced in mice lacking Bruton tyrosine kinase, but not in mice treated with 4 weeks of acalabrutinib, a more specific Bruton tyrosine kinase inhibitor, demonstrating that AF is an off-target side effect. Chemoproteomic profiling identified a short list of candidate kinases that was narrowed by additional experimentation leaving CSK (C-terminal Src kinase) as the strongest candidate for ibrutinib-induced AF. Cardiac-specific Csk knockout in mice led to increased AF, left atrial enlargement, fibrosis, and inflammation, phenocopying ibrutinib treatment. Disproportionality analyses in VigiBase confirmed increased reporting of AF associated with kinase inhibitors blocking Csk versus non-Csk inhibitors, with a reporting odds ratio of 8.0 (95% CI, 7.3-8.7; P<0.0001). These data identify Csk inhibition as the mechanism through which ibrutinib leads to AF. Registration: URL: https://ww.clinicaltrials.gov; Unique identifier: NCT03530215.

Abstract 5262: Identifying the role of AXL in fusion kinase inhibitor resistant non-small cell lung cancer

Abstract Chromosomal rearrangements involving ALK, ROS1, RET and others generate novel fusion kinases which comprise approximately 10% of the oncogenic drivers in lung adenocarcinoma. Several tyrosine kinase inhibitors (TKIs) are approved or in development for each of these oncogenes and have shown marked clinical improvement for patients, but resistance inevitably occurs, a significant proportion of which is not currently druggable. AXL is a receptor tyrosine kinase that is often upregulated in resistant cancers in response to both chemotherapy and targeted therapies such as EGFR inhibitors. AXL can promote resistance to targeted therapy by signaling through the MAPK and Akt pathways or heterodimerizing with other receptors to maintain growth and survival signaling. However, the role of AXL in mediating resistance to ALK, ROS1, and RET TKIs is not well understood. In screening our unique panel of patient-derived lung adenocarcinoma cell lines harboring ALK, ROS1 or RET gene fusions, we found elevated AXL expression was correlated with resistance to cognate TKIs, as well as mesenchymal features including spindle morphology and vimentin expression. Combining the AXL inhibitor R428 with TKI treatment, such as crizotinib for ALK and ROS1 driven cell lines, was effective at inhibiting colony formation and wound healing in fusion kinase inhibitor resistant cell lines. Combination treatment downregulates Akt phosphorylation in resistant cells, and we found the resistant cell lines were also more sensitive to PI3K inhibition than cell lines that are still sensitive to their specific TKI. Interestingly, we also identified AXL cross talk with other receptor tyrosine kinases. In a RET inhibitor resistant model expression of both AXL and EGFR are elevated and the receptors interact, which can be disrupted upon EGF stimulation, to drive resistance. Collectively, we show that AXL upregulation is a common marker of TKI resistance among ALK, ROS1, and RET fusion kinase driven lung adenocarcinoma models, and provide rationale for AXL as a clinical target for combination therapy to overcome drug resistance. Citation Format: Tara Peters, Anastasios Dimou, Anh Le, Robert Doebele. Identifying the role of AXL in fusion kinase inhibitor resistant non-small cell lung cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5262.

Clinical Features and Outcomes of Patients With Chronic Myeloid Leukemia Presenting With Isolated Thrombocytosis: A Systematic Review and a Case From Our Institution.

Chronic myeloid leukemia (CML) represents a common condition in the spectrum of myeloproliferative disorders (MPD). It classically exhibits leukocytosis, but rarely presents with isolated thrombocytosis. This paper is designed to review the clinicopathologic features, treatment, and outcomes of patients with CML who present with isolated thrombocytosis.We searched PubMed, MEDLINE®, ScienceDirect, and Scopus for English-language articles about case series and case reports for the period 2000-2020 with the terms “chronic myeloid leukemia” and “thrombocytosis” and pooled them with a case from our institution. Cases were also incorporated from the reference list and screened for inclusion. A total of 20 cases were included in the final cohort. The male-to-female ratio was 1:1.86. The mean age of the patients at the time of initial diagnosis was 40.5 years (range: 9-77 years). Out of 17 cases with available data, seven (41%) were asymptomatic and found to have thrombocytosis incidentally upon routine blood work. Five cases (29.4%) either had a history of thrombotic events or presented with severe thrombotic complications, including ischemic cerebrovascular accidents (CVA), myocardial infarction (MI), pulmonary embolism (PE), and/or miscarriages. Four cases (23.5%) had more than one symptom at presentation, including headache, syncope, and bruising. The average platelet count was 1,923 × 109/L (range: 584-8,688 × 109/L), and one case (5%) had anemia. The bone marrow (BM) examination showed normal cellularity and normal myeloid to erythroid (M/E) ratio in seven (50%) and 11 (84.6%) out of the 14 and 13 cases with reported data, respectively. Moreover, megakaryocytes in the BM were small in 10 cases (71.4%), pleomorphic in three cases (21.4%), and dysplastic in one case (7.1%).Accurate differentiation among MPD subtypes and the exclusion of CML is critical in reaching a proper diagnosis to decide on proper therapy and eventually modify outcomes. Prompt evaluation for the precise diagnosis of patients presenting with isolated marked thrombocytosis will help expedite their diagnosis and initiation of a specific tyrosine kinase inhibitor (TKI) therapy, thereby promptly inducing remission, preventing thrombotic complications, and avoiding adverse drug events, which would eventually improve outcomes.

Significance of metastatic topography for the immunotherapy of cutaneous and ocular melanomas

PD-1 is expressed on the surface of activated T lymphocytes and belongs to the category of negative immune stimuli. Its blocking stimulates the immune response to tumor antigens. Ocular melanomas represent 3-4% of the total melanomas and have metastatic potential, especially to the liver but also to the lungs, skin, and bones. In the case of metastatic melanoma, immunotherapy has a unique role due to the lower frequencies of BRAF mutation in choroidal melanomas and consecutive exclusion from treatment with specific BRAF tyrosine kinase inhibitors. A retrospective observational study was performed in 42 patients who received immunotherapy (IT) with nivolumab for cutaneous and ocular metastatic melanomas, aimed at highlighting the association between the topography of metastases and the duration of immunotherapy until progressive disease. The results indicated the presence of liver metastases as a negative predictive factor for IT duration in patients with melanoma and the presence of lymphatic metastases as a predictive factor for longer IT in patients with melanoma under 65 years old.

New Therapeutics in HER2-Positive Advanced Breast Cancer: Towards a Change in Clinical Practices?pi.

Over the last few decades, improved knowledge of oncogenic activation mechanisms of HER2 protein has led to the development of HER2 targeted therapies that are currently commonly used in HER2-positive advanced breast cancer, such as trastuzumab, lapatinib, pertuzumab, and ado-trastuzumab emtansine. The management of this breast cancer subgroup has thus been revolutionized and its prognosis has changed dramatically. Nevertheless, HER2-positive advanced breast cancer remains an incurable disease and resistance to conventional anti-HER2 drugs is almost unavoidable. Nowadays, biochemical and pharmaceutical advances are meeting the challenge of developing increasingly sophisticated therapies directed against HER2, including novel anti HER2 antibodies with increased affinity. New antibody-drug conjugates (ADC) with more advanced pharmacological properties, and dual targeting of epitopes via bispecific monoclonal antibodies are also emerging. In addition, more potent and more specific HER2 tyrosine kinase inhibitors have shown interesting outcomes and are under development. Finally, researchers’ interest in tumor microenvironment, particularly tumor-infiltrating lymphocytes, and the major role that signaling pathways, such as the PI3K/AKT/mTOR pathway, play in the development of resistance to anti-HER2 therapies have spurred the development of clinical trials evaluating innovative combinations of anti-HER2 with PD-1/PDL-1, CDK4/6 and PI3K inhibitors. However, several questions remain unresolved, like the optimal management of HER2-positive/HR-positive advanced breast cancer and the identification of predictive biomarkers to better define populations that can benefit most from these new therapies and approaches.

Factors affecting high-grade hepatotoxicity of tyrosine kinase inhibitors in cancer patients: a multi-center observational study.

Although several studies have examined tyrosine kinase inhibitor (TKI)-induced hepatotoxicity, the majority of patients in those studies displayed low-grade (grade I-II) hepatotoxicity. The purpose of this study was to investigate factors affecting high-grade (grade III-IV) hepatotoxicity of TKIs. This multi-center, retrospective study used individual patient data from five studies that examined factors affecting hepatotoxicity by TKIs (crizotinib, erlotinib, gefitinib, imatinib, and lapatinib). Odds ratio (OR) and adjusted OR (AOR) were estimated from univariate and multivariate analyses, respectively. Data from 1279 patients treated with TKIs were analyzed. The rate of patients who experienced high-grade hepatotoxicity after TKI administration was 5.5%. In multivariable analysis, H2 blockers and CYP3A4 inducers increased high-grade hepatotoxicity 2.2- (95% CI 1.255-3.944) and 3.3-fold (95% CI 1.260-8.698), respectively. Patients with liver metastasis revealed a 3.4-fold (95% CI 1.561-7.466) higher risk of high-grade hepatotoxicity. Among underlying malignancies, pancreatic cancer and other cancers including acute lymphoblastic leukemia increased the risk of high-grade hepatotoxicity by 2.6- and 24.3-fold, respectively, whereas breast cancer decreased the risk (AOR 0.3, 95% CI 0.106-0.852), compared to non-small cell lung cancer. In patients who administrated TKIs which form reactive metabolites, use of CYP3A4 inducers and liver metastasis increased incidence of high-grade hepatotoxicity by 3.0- and 2.3-fold, respectively. In patients with EGFR mutation, exon 19 deletion and use of proton pump inhibitors were risk factors for high-grade hepatotoxicity in addition to liver metastasis and use of H2 blockers. The use of H2 blockers, presence of liver metastasis, and CYP3A4 inducers were associated with high-grade hepatotoxicity of TKIs. In subgroup analyses, presence of exon 19 deletion, and/or proton pump inhibitors, was additional risk factors for high-grade hepatotoxicity in special patients and use of specific TKIs. Close liver function monitoring is recommended, especially in patients with liver metastasis or using H2 blockers or CYP3A4 inducers.

Distinct genomic instability landscape of lung adenocarcinoma associated with treatment and metastasis.

9534 Background: Lung adenocarcinoma (LUAD) is the most common subtype of non-small cell lung cancer (NSCLC). Genomic instability, defined as genome-wide copy number alterations, is a key pathogenic signature which occurs at the early stage of most cancers and is associated with an increased risk of recurrence or death. We examined the pattern of genomic instability in primary and metastatic LUAD. Methods: We performed deep targeted sequencing (425 genes) of 3395 tissue samples and whole exome sequencing (WES) of 60 tissue samples from LUAD patients. Whole-genome doubling (WGD) and arm level aneuploidy were analyzed to uncover correlation with clinical phenotypes and other genomic alterations including driver mutations, tumor mutation burden (TMB), and microsatellite instability (MSI). Results: Overall, targeted sequencing revealed that WGD occurred in 64.33% LUAD samples, which was comparable with WES results. Compared to primary site, metastasis exhibited higher proportion of WGD (1.14 fold). Specifically, liver metastasis has the highest WGD percentage among metastasis sites (~87.5%; 1.40 fold increase compared to primary). Interestingly, patients who received tyrosine kinase inhibitors (TKI) had higher frequency of WGD than patients without TKI treatment. In addition, TMB was higher in WGD+ patients but MSI status was not significantly different between groups. Arm-level aneuploidy was prevalent in this cohort. The most common amplification events were 7p gain (62%), 5p gain (54%), and 8q gain (53%); top deletion events were 19p loss (47%), 15q loss (42%), and 10 q loss (41%). Patients with EGFR or TP53 mutation were more likely to have aneuploidy compared to wildtypes. Subgroup analysis showed distinct patterns of aneuploidy among metastasis sites, suggesting organ-specific alterations. Evolution analysis showed 7p gain was an early event common in primary tumor whereas metastatic tumor had multiple distinct evolutionary trajectories following 7p gain. Several copy number signatures were associated with specific TKI and chemotherapies. For example, TKI-naïve tumors lacked 7p gain but had 19p loss as the most common alteration. Conclusions: The genomic landscape of LUAD was characterized by widespread large-scale copy number alterations including WGD and chromosomal aneuploidy. Metastasis had elevated level of aneuploidy compared to primary tumors which were specific to metastatic site. Copy number signature associated with different treatments may contribute to distinct long-term survival and side effects among patients.

A phase III, open-label, randomized study of atezolizumab in combination with carboplatin + paclitaxel + bevacizumab compared with pemetrexed + cisplatin or carboplatin with stage IV non-squamous non-small cell lung cancer (NSCLC) with activating EGFR mutation or ALK translocation (ATLAS Trial).

TPS9636 Background: In patients with activating EGFR mutations and ALK fusion, target specific tyrosine kinase inhibitor (TKI) showed significant survival improvement compared to the cytotoxic chemotherapy. However, the questions remain which combination strategy will be the best option for the patients who have failed from TKI. Especially, the role of an immune checkpoint inhibitor (ICI) in this population is still unclear. This study is designed and conducted based on the recent subgroup analyses from the IMpower 150 study which showed the positive clinical outcomes of atezolizumab combined with VEGF inhibitor and conventional cytotoxic chemotherapy in EGFR mutation and ALK translocation. Methods: This study is the phase III, open-label, multicenter study of atezolizumab in combination with bevacizumab + carboplatin + paclitaxel (ABCP, Arm A) compared with pemetrexed + cisplatin or carboplatin (Arm B). The study population will be randomized to either Arm A (n = 152) or Arm B (n = 72) based on two stratification factors, EGFR vs. ALK and presence of brain metastases. In Arm A, patients will be treated with 4 or 6 cycles of ABCP followed by maintenance atezolizumab and bevacizumab every three weeks. In Arm B, pemetrexed maintenance therapy will be applied every three weeks after 4 or 6 cycles of pemetrexed + cisplatin or carboplatin. As key inclusion criteria, the patients must be diagnosed with stage IV non-squamous non-small cell lung cancer with either activating EGFR mutation or ALK translocation. All the patients need to be cytotoxic chemotherapy naïve and must have experienced disease progression to treatment with at least one EGFR or ALK TKI. If the patients have T790M mutation after 1st or 2nd generation EGFR TKI, second line 3rd generation EGFR TKI treatment is mandatory. The number of T790M positive patients is restricted to under 30% of the entire study population. The primary endpoint is progression-free survival and the major secondary endpoints are overall survival, objective response rate and duration of response. A total of 228 subjects will be enrolled to detect a hazard ratio of 0.67. The first subject received treatment in Aug. 2019 and 19 patients receive the treatment. This study is opened in 3 sites and expected to be opened at 18 sites in South Korea. The time point for the primary analyses is Q3. 2022. Clinical trial information: NCT03991403 .

EGFR-A763_Y764insFQEA Is a Unique Exon 20 Insertion Mutation That Displays Sensitivity to Approved and In-Development Lung Cancer EGFR Tyrosine Kinase Inhibitors

IntroductionThe EGFR-A763_Y764insFQEA is a unique exon 20 insertion mutation (∼5% to 6% of exon 20 insertions), which, at the structural and enzyme kinetic level, more closely resembles EGFR tyrosine kinase inhibitor (TKI)–sensitizing mutants, such as EGFR exon 19 indels and L858R. A limited number of preclinical models and clinical reports have studied the response of this mutant to EGFR TKIs. MethodsWe used models of EGFR-A763_Y764insFQEA and more typical EGFR exon 20 insertion mutations to probe representative first- (gefitinib, erlotinib), second- (afatinib), third-generation (osimertinib), and in-development EGFR exon 20–specific (poziotinib, mobocertinib [TAK-788]) TKIs. We also compiled outcomes of EGFR-A763_Y764insFQEA-mutated lung cancers treated with EGFR TKIs. ResultsCells driven by EGFR-A763_Y764insFQEA were consistently sensitive to EGFR TKIs (as opposed to those driven by typical EGFR exon 20 insertions [A767_V769dupASV, D770_N771insSVD and H773_V774insH]), which were only inhibited by in-development EGFR TKIs at doses below those affecting wild-type EGFR. Most case instances (62.5% [95% confidence interval: 39%–86%], n = 16) with lung cancers harboring EGFR-A763_Y764insFQEA responded to clinically available EGFR TKIs (including osimertinib) and to in-development EGFR exon 20-specific TKIs (including mobocertinib) with prolonged periods of progression-free survival in some cases. Median overall survival for EGFR TKI–treated cases was 22 months (95% confidence interval: 16–25). Mechanisms of acquired TKI resistance of this mutant remain underreported, but do seem to align with those of common mutations. ConclusionsTo our knowledge, this is the largest report to confirm that the EGFR-A763_Y764insFQEA mutation is sensitive to clinically available first-, second-, third-generation, and in-development EGFR TKIs.

Oncogene-Addicted Non-Small-Cell Lung Cancer: Treatment Opportunities and Future Perspectives.

Before the introduction of tyrosine kinase inhibitors (TKIs) for a particular subgroup of patients, despite platinum-based combination chemotherapy, the majority of patients affected by non-small-cell lung cancer (NSCLC) did not live longer than one year. With deeper understanding of tumor molecular biology, treatment of NSCLC has progressively entered the era of treatment customization according to tumor molecular characteristics, as well as histology. All this information allowed the development of personalized molecular targeted therapies. A series of studies have shown that, in some cases, cancer cells can grow and survive as result of the presence of a single driver genomic abnormality. This phenomenon, called oncogene-addiction, more often occurs in adenocarcinoma histology, in non-smokers (except BRAF mutations, also frequent in smoking patients), young, and female patients. Several different driver mutations have been identified and many studies have clearly shown that upfront TKI monotherapy may improve the overall outcome of these patients. The greater efficacy of these drugs is also associated with a better tolerability and safety than chemotherapy, with fewer side effects and an extremely good compliance to treatment. The most frequent oncogene-addicted disease is represented by those tumors carrying a mutation of the epidermal growth factor receptor (EGFR). The development of first, second and third generation TKIs against EGFR mutations have dramatically changed the prognosis of these patients. Currently, osimertinib (which demonstrated to improve efficacy with a better tolerability in comparison with first-generation TKIs) is considered the best treatment option for patients affected by NSCLC harboring a common EGFR mutation. EML4-ALK-driven disease (which gene re-arrangement occurs in 3–7% of NSCLC), has demonstrated to be significantly targeted by specific TKIs, which have improved outcome in comparison with chemotherapy. To date, alectinib is considered the best treatment option for these patients, with other newer agents upcoming. Other additional driver abnormalities, such as ROS1, BRAF, MET, RET and NTRK, have been identified as a target mirroring peculiar vulnerability to specific agents. Oncogene-addicted disease typically has a low early resistance rate, but late acquired resistance always develops and therefore therapy needs to be changed when progression occurs. In this narrative review, the state of art of scientific literature about targeted therapy options in oncogene-addicted disease is summarized and critically discussed. We also aim to analyze future perspectives to maximize benefits for this subgroup of patients.

Decoy receptor 2 mediation of the senescent phenotype of tubular cells by interacting with peroxiredoxin 1 presents a novel mechanism of renal fibrosis in diabetic nephropathy

Premature senescence of renal tubular epithelial cell (RTEC), which is involved in kidney fibrosis, is a key event in the progression of diabetic nephropathy. However, the underlying mechanism remains unclear. Here we investigated the role and mechanism of decoy receptor 2 (DcR2) in kidney fibrosis and the senescent phenotype of RTEC. DcR2 was specifically expressed in senescent RTEC and associated with kidney fibrosis in patients with diabetic nephropathy and mice with streptozotocin-induced with diabetic nephropathy. Knockdown of DcR2 decreased the expression of α-smooth muscle actin, collagen I, fibronectin and serum creatinine levels in streptozotocin-induced mice. DcR2 knockdown also inhibited the expression of senescent markers p16, p21, senescence-associated beta-galactosidase and senescence-associated heterochromatic foci and promoted the secretion of a senescence-associated secretory phenotype including IL-6, TGF-β1, and matrix metalloproteinase 2 invitro and invivo. However, DcR2 overexpression showed the opposite effects. Quantitative proteomics and validation studies revealed that DcR2 interacted with peroxiredoxin 1 (PRDX1), which regulated the cell cycle and senescence. Knockdown of PRDX1 upregulated p16 and cyclin D1 while downregulating cyclin-dependent kinase 6 expression invitro, resulting in RTEC senescence. Furthermore, PRDX1 knockdown promoted DcR2-induced p16, cyclin D1, IL-6, and TGF-β1 expression, whereas PRDX1 overexpression led to the opposite results. Subsequently, DcR2 regulated PRDX1 phosphorylation, which could be inhibited by the specific tyrosine kinase inhibitor genistein. Thus, DcR2 mediated the senescent phenotype of RTEC and kidney fibrosis by interacting with PRDX1. Hence, DcR2 may act as a potential therapeutic target for the amelioration of diabetic nephropathy progression.

Pediatric bithalamic gliomas have a distinct epigenetic signature and frequent EGFR exon 20 insertions resulting in potential sensitivity to targeted kinase inhibition.

Brain tumors are the most common solid tumors of childhood, and the genetic drivers and optimal therapeutic strategies for many of the different subtypes remain unknown. Here, we identify that bithalamic gliomas harbor frequent mutations in the EGFR oncogene, only rare histone H3 mutation (in contrast to their unilateral counterparts), and a distinct genome-wide DNA methylation profile compared to all other glioma subtypes studied to date. These EGFR mutations are either small in-frame insertions within exon 20 (intracellular tyrosine kinase domain) or missense mutations within exon 7 (extracellular ligand-binding domain) that occur in the absence of accompanying gene amplification. We find these EGFR mutations are oncogenic in primary astrocyte models and confer sensitivity to specific tyrosine kinase inhibitors dependent on location within the kinase domain or extracellular domain. We initiated treatment with targeted kinase inhibitors in four children whose tumors harbor EGFR mutations with encouraging results. This study identifies a promising genomically-tailored therapeutic strategy for bithalamic gliomas, a lethal and genetically distinct brain tumor of childhood.

A profile on cobas® EGFR Mutation Test v2 as companion diagnostic for first-line treatment of patients with non-small cell lung cancer

ABSTRACT Introduction Among non-small cell lung cancer (NSCLC) patients, there is one molecularly defined subgroup harboring activating mutations in the epidermal growth factor receptor gene (EGFR), which results in constitutive activation of its intrinsic kinase activity. Consistent data have demonstrated that these patients have a better outcome when treated with specific tyrosine-kinase inhibitors (EGFR-TKIs). Therefore, analysis of EGFR mutational status for treatment guidance is mandatory in this context. Areas covered Herein we review the clinical development and technical features of cobas® EGFR Mutation Test v2 as a companion diagnostic test (CDx) for therapy with EGFR-TKIs, such as gefitinib, in advanced NSCLC. We also discuss the pros and cons of the current version of the CDx and its performance in both tissue and plasma samples. Expert opinion The RT-PCR based cobas® EGFR Mutation Test v2 is a reliable and rapid solution for EGFR mutational status assessment at the time of diagnosis in advanced NSCLC that allows eligibility of patients for EGFR-TKI treatment. This test determines EGFR mutations with acceptable sensitivity in tissue or plasma samples. Pre-analytical considerations like tumor cell content, tumor burden or location of metastasis should be considered to better interpret results in the clinical contexture.

Abstract GS2-02: Acquired activating mutations in RTKs confer endocrine resistance in ER+ metastatic breast cancer through ER-reprogramming, MAPK signaling, and an induced stem-like cell state

While recent studies have begun characterizing the metastatic breast cancer (MBC) genomics, our understanding of mechanisms of acquired endocrine-resistance, their induced cell-state, and their altered drug-response profile, remains lacking. We collected biopsies from patients with MBC with detailed clinicopathologic features. To date we profiled 520 exomes, and 291 transcriptomes, with 126 patients having multiple biopsy exomes. Curated endocrine-relapse set include 60 patients with pre-treatment and post-relapse exomes. Characterization of candidate mechanisms of resistance (MOR) included 909 RNA-seq profiles of T47D cells with introduced MOR under various drugs. In the acquired endocrine resistance cohort, as expected, we found frequent ESR1 acquired mutations (13 pt, 22%). Additionally, we identified acquired activating SNVs and amplifications in oncogenic receptor tyrosine kinases (RTKs) in 18/60 (30%), including EGF family - HER2 (n=7), ERRB3 (R525Q), and EGFR (S116F), and FGF family - FGFR1 (n=5), FGFR2 (n=4), and FGF3 amplicon (n=4). RNA-seq of T47D cells overexpressing HER2 activating mutations revealed a distinct cell-state (HER2-ACT). Similarly, FGFR activation revealed a district FGFR-ACT state. The transcriptional signatures of these HER2 and FGFR states were remarkably similar (odd-ratio= 91, p= 2.64E-94). To characterize the cell-state common to HER and FGFR, we defined RTK-ACT with 358 overlapping marker genes (see table). Canonical (estradiol) ER signaling is slightly elevated in RTK-ACT, however this state is strongly associated with growth-factor driven ER signaling, suggesting reprogramming of ER from AF2, to AF1 signaling. Consistent with this, RTK-ACT had significantly higher MAPK activation. Additionally, RTK-ACT Induced stronger similarity to Basal-state, enrichment in motility/migration, mesenchymal, and stem-like features, with top genes including CDH3, MBP7, and S100, ETV, DUSP, SPRY families (see table). To study RTK-driven state in-vivo, we analyzed RNA-seq from our MBC biopsies, and compared tumors with activating RTK mutations (n=38) with WT (n=118), and inferred activated RTK in-vivo (RTK.ACT.iv). Our in-vitro and in-vivo states show significant overlap (OR=4.71, p=9.42E-20). Furthermore, characterization of RTK.ACT.iv, recapitulated all the cell-state features observed in RTK.ACT - including higher growth-factors ER signaling, MAPK, and basal-like state (see table). We further studied the viability and transcription of these RTKs under various drugs (12 treatments), including fulvestrant, palbociclib, and specific tyrosine kinase inhibitors (TKIs) - Neratinib (pan-HER inhibitor) and FIIN-3 (FGFR-i). We found that HER2-ACT and FGFR-ACT signatures remain robust when treated with fulvestrant, palbociclib, and their combinations, as compared to TKIs suppression (see table). in-line with our viability results - suggesting intrinsic resistance to CDK4/6i and sensitivity to TKIs. This study demonstrated that activating RTKs constitute of prevalent modality of acquired resistance to endocrine therapies, inducing a distinct state with clinical implications - suggesting the potential benefit of combination therapies with specific TKIs over CDK4/6i. The common MAPK activity and our preliminary results - suggests the potential of convergence-node targeting strategy with added MEK or SHP2 inhibition. Citation Format: Ofir Cohen, Pingping Mao, Utthara Nayar, Jorge E Buendia-Bue, Dewey Kim, Esha Jain, Karla Helvie, Daniel Abravanel, Kailey J Kowalski, Christian Kapstad, Samuel Freeman, Victor Adalsteinsson, Seth A Wander, Adrienne G Waks, Gad Getz, Aviv Regev, Eric Winer P Winer, Nancy U Nancy U. Lin, Nikhil Wagle. Acquired activating mutations in RTKs confer endocrine resistance in ER+ metastatic breast cancer through ER-reprogramming, MAPK signaling, and an induced stem-like cell state [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr GS2-02.

Abstract OT2-01-02: TBCRC049: A phase II non-randomized study to assess the safety and efficacy of the combination of tucatinib and trastuzumab and capecitabine for treatment of leptomeningeal metastases in HER2 positive breast cancer TBCRC049: A phase II non-randomized study to assess the safety and efficacy of the combination of tucatinib and trastuzumab and capecitabine for treatment of leptomeningeal metastases in

Abstract Background: Treatment options for patients with leptomeningeal disease (LMD) from HER2-positive breast cancer (HER2+ BC) are limited, and the prognosis is poor. Tucatinib is an oral, potent, HER2 specific tyrosine kinase inhibitor with good tolerability and notable early combinatory anti-tumor activity, including partial responses in heavily treated patients and those with parenchymal brain metastases (BM). Trial Design: This is a phase 2 single arm study to evaluate the efficacy of the combination of tucatinib plus trastuzumab (T) and capecitabine(C) in patients with HER2+ BC and newly diagnosed LMD. CNS disease will be evaluated at screening and every six weeks by MRI, CSF cytology, and neurological assessments according to RANO-LMD (adapted) and RANO-BM criteria. CT scans/PET-CT will evaluate extracranial disease according to RECIST criteria at screening and every 12 weeks. All patients will be followed for survival from the date of the last dose until death, lost to follow-up, or consent withdrawal. Symptom burden and quality of life assessments are conducted throughout the study. Blood and CSF sample collections occur at each cycle for the planned correlative analyses. Eligibility Criteria: Eligible patients are adults (&amp;gt;18 years old) with HER2+ BC, ECOG status&amp;lt;3/KPS&amp;gt;50, and newly diagnosed untreated LMD (defined as positive CSF cytology and/or radiographic evidence of LMD, plus clinical signs/symptoms. Patients with a history of treated BM or concurrent/new BM are allowed. Patients previously treated with tucatinib or capecitabine (within the last 12 months) are excluded. Specific Aims: The primary endpoint is OS. Secondary endpoints include safety, CNS PFS at 12 weeks, RR and CBR in CNS and extra-CNS disease, and symptom burden/quality of life. Statistical methods: This study has a Gehan-like design with an interim futility analysis and overall intent to estimate OS. For the interim analysis, we define success to be CNS PFS for 12 weeks. An event will be considered to be either CNS progression or death from any cause before 12 weeks.We will stop enrollment if there are fewer than two successes in the first 15 patients. If the trial continues to completion, the regimen will be considered worthy of future study if the median overall survival is &amp;gt; 4.4 months. Study Accrual: The target accrual is 30 patients. The study is currently active at UAB and MDACC. Other TBCRC sites throughout the country are to be activated this year. Citation Format: Rashmi K Murthy, Barbara J O'Brien, Ken R Hess, Nick Navin, Jason Johnson, Maria Gule-Monroe, Jose P Leone, Jennifer Specht, Michelle Melisko, Aki Morikawa, Anna M Storniolo, Adam Brufsky, Paula R Pohlmann, Deric M Park, Ben H Park, Ian Krop, Nancy U Lin, Antonio Wolff, Andres Forerro-Torres, Erica Stringer-Reasor. TBCRC049: A phase II non-randomized study to assess the safety and efficacy of the combination of tucatinib and trastuzumab and capecitabine for treatment of leptomeningeal metastases in HER2 positive breast cancer TBCRC049: A phase II non-randomized study to assess the safety and efficacy of the combination of tucatinib and trastuzumab and capecitabine for treatment of leptomeningeal metastases in HER2 positive breast cancer [abstract]. In: Proceedings of the 2019 San Antonio Breast Cancer Symposium; 2019 Dec 10-14; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2020;80(4 Suppl):Abstract nr OT2-01-02.