Multiple Anaplastic Lymphoma Kinase Research Articles

Multiple anaplastic lymphoma kinase-positive primary inflammatory myofibroblastic tumors with spontaneously expanding and shrinking nodules in both lungs: a case report

BackgroundInflammatory myofibroblastic tumors (IMTs) are uncommon neoplasms most prevalent in individuals under 40 years old and predominantly in the lungs. Despite their rarity, multiple anaplastic lymphoma kinase (ALK)-positive IMTs, especially those of various sizes, have not been widely reported. This report describes a case of multiple ALK-positive IMTs in the lungs, aiming to further our understanding of their behavior and management.Case presentationHerein, we present the case of a 64-year-old woman who presented with an abnormal shadow on chest examination. Chest computed tomography revealed a main tumor in the right middle lobe and multiple irregularly shaped small nodules in both lungs. Thus, thoracoscopic wedge resection of the left lower lobe was performed for diagnosis. Pathological findings indicated smooth muscle proliferation without malignancy. IMT was diagnosed following thoracoscopic right middle lobectomy. Twenty months postoperatively, one residual nodule shrank, but another grew.ConclusionsThis is the first report of multiple ALK-positive IMTs in both lungs, highlighting the need for definitive diagnosis and treatment of IMTs based on surgical resection. Although caution is required in patients with lymph node metastases or distant metastases, careful follow-up is acceptable unless there is a tendency for nodules to increase in size on imaging.

Superior clinical outcomes in patients with non-small cell lung cancer harboring multiple ALK fusions treated with tyrosine kinase inhibitors.

Patients with non-small cell lung cancer (NSCLC) harboring anaplastic lymphoma kinase (ALK) fusions may benefit from ALK-tyrosine kinase inhibitors (ALK-TKIs). However, few studies have analyzed the clinical outcome in patients harboring multiple ALK fusions, including double or triple ALK fusions. Here, our study aimed to analyze the impact of harboring multiple ALK fusions on the efficacy of receiving ALK-TKIs in NSCLC patients. A total of 125 patients with ALK-rearranged NSCLC detected by targeted capture DNA-based next-generation sequencing (NGS) at West China Hospital were enrolled. The literature on patients harboring multiple ALK fusions was systematically reviewed. The clinical response to ALK-TKIs was evaluated according to ALK fusion patterns in 62 patients: 56 from our center and 6 from the literature. Among the 125 patients, a single canonical echinoderm microtubule-associated protein-like 4 (EML4)-ALK fusion was detected in 65.6% (82/125), a single non-EML4-ALK fusion was detected in 13.6% (17/125), and multiple ALK fusions were detected in 20.8% (26/125). Among the 62 patients with ALK fusion treated with ALK-TKIs, the median progression-free survival (PFS) was significantly longer in patients with multiple ALK fusions than in those with a single ALK fusion (26.9 vs. 11.2 months, P=0.009), irrespective of brain metastasis, type of TKI drug, and treatment lines. The multiple ALK fusion group also tended to have a longer overall survival (OS) (P=0.26). Multivariate Cox regression analysis revealed that harboring multiple ALK fusions had the potential to be an independent predictor of better PFS for ALK-positive NSCLC [hazard ratio (HR) =0.490; 95% confidence interval (CI): 0.229-1.049]. Harboring multiple ALK fusions could serve as an independent predictive marker of better clinical outcome for patients with NSCLC and ALK rearrangement who have received ALK-TKIs treatment.

ALK fusion typing and response to crizotinib in ALK+ lung cancer-naive patients.

e21008 Background: Anaplastic lymphoma kinase (ALK) is one of the major oncogenic driver genes in lung cancer, and fusion as the main mutation type, of which EML4 is the most common fusion ligand. With the development of next-generation sequencing (NGS), some other rare fusion ligands and complex fusions have been discovered. The prognosis of patients with EML4-ALK fusion, non EML4-ALK fusion and multiple ALK fusion was different. Methods: We retrospectively analyzed NGS (including tissue, blood, or other body fluid samples) in 61 patients with ALK[+] lung cancer, including 59 patients with NSCLC and 2 patients with SCLC. Grouping was determined according to whether it was EML4-ALK fusion and multiple fusion. Results: In our data, the partner fused to the ALK gene are diverse, including EML4, KIF5B, TSN and others. Among them, EML4 was the most common ligand in ALK[+] NSCLC, accounting for 93.2% (55/59). Among the different fusion sites of EML4-ALK, V1 (E13:A20) and V3 (E6:A20) mutations were the most common, accounting for 45.5% (25/55) and 41.8% (23/55), respectively. Several novel ALK fusion partners were discovered in this study, including MCFD2, LINC01251, MVP17, CREG2, LINCO1498 and so on. In addition, the incidence of intergenic sequence-ALK fusions was 16.4% (10/61), such as ANXA4-ALK(A[intergenic]:A20), CREG2-ALK (C[intergenic]:A20), HCN1-ALK(H[intergenic]:A20), TSN-ALK(T[intergenic]:A20), RSAD2-ALK(R [intergenic]:A20) and so on. 19.0% (12/61) of the patient had multiple fusion, of which only one patient had multiple fusion of EML4-ALK (V2+V5'+V3a/b), and the remaining patients had co-fusion of EML4-ALK and non EML4-ALK (Table). V3 were more likely to coexist with non EML4-ALK fusions than V1 or other variants (P = 0.047). Multiple fusions were more likely to occur with non EML4-ALK fusions (P < 0.000). Compared with EML4-ALK fusion, mPFS treated with crizotinib in non EML4-ALK fusion were significantly shorter (18.2 vs. 8.5 months, P = 0.035). In the context of crizotinib treatment, multiple fusions were associated with worse mPFS compared with single fusions (13.8 vs. 8.4 months, P = 0.008). In addition, For SCLC patients with ALK fusion (n = 2), the PFS of crizotinib treatment were 8.0 and 30.6 months, respectively. Conclusions: Due to the heterogeneity of tumor development resulting in the diversity of ALK fusions, non EML4-ALK fusions and multiple fusions imply a poorer response to crizotinib. ALK gene status prior to ALK-TKI therapy helps predict drug efficacy and patient prognosis.[Table: see text]

Strengths and pitfalls of brigatinib in non-small cell lung cancer patients' management.

The treatment landscape of advanced non-small cell lung cancer (NSCLC) patients has dramatically changed over the past 10 years, particularly thanks to the advent and development of several tyrosine kinase inhibitors (TKI) targeting oncogenic drivers. Among them, patients bearing anaplastic lymphoma kinase (ALK) translocations, which are causative of 3-5% of all advanced NSCLC, have seen dramatically improved their clinical outcomes moving life expectancy at 5 years from less than 5% to 50%. In fact, multiple ALK inhibitors (ALKi) entered in the therapeutic algorithm of ALK+ patients, multiplying their treatment opportunities. Remarkably, in the near future we could take advantage of up to different 6 molecules for the first-line approach (crizotinib, ceritinib, alectinib, brigatinib, plus ensartinib and lorlatinib). Among available ALKi, brigatinib, a second-generation (2G) inhibitor, showed notable activity in this setting, also against central nervous system (CNS) disease, and a good safety profile, supporting its approval as upfront treatment based on the ALTA-1L trial results. With a peculiar profile of enzymatic targets, brigatinib represents a valuable opportunity in the ALK targeting journey, albeit having to balance its safety profile. The abundance of therapeutic options for these patients poses nontrivial questions; in absence of direct comparisons of efficacy is not easy to define the best approach and, more compelling, the correct administration sequence in order to give the best therapeutic chances to ALK+ lung cancer patients. In such wide variety of options, we reviewed the preclinical and clinical efficacy data of brigatinib, its pharmacological and safety profile, like also actual and potential future applications in the ALK+ NSCLC scenario. Through a spurious exercise of an indirect comparison with other available 2G ALKi, we tent to summarize the required knowledge to properly choose the best drug at the right time. Furthermore, we reviewed available data on molecular resistance mechanisms and putative therapeutic applications in other contexts, such as ROS1+ NSCLC patients or EGFR+ ones progressing to osimertinib.

Real-world circulating tumor DNA analysis depicts resistance mechanism and clonal evolution in ALK inhibitor-treated lung adenocarcinoma patients

BackgroundSequential treatment with different generations of anaplastic lymphoma kinase (ALK) inhibitors have been widely applied to ALK-positive lung cancer; however, resistance mutations inevitably developed. Further characterization of ALK resistance mutations may provide key guidance to subsequent therapies. Here we explored the emergence of secondary ALK mutations during sequential ALK tyrosine kinase inhibitor (TKI) treatment in a real-world study of Chinese lung adenocarcinoma (ADC) patients.MethodsA clinical-genomic database was queried for lung ADC patients with at least one ALK inhibitor treatment and at least one plasma sample collected following ALK inhibitor treatment. Targeted genome profiling was performed with a 139-gene panel in baseline tumor tissue and serial plasma samples of patients.ResultsA total of 116 patients met inclusion criteria. ALK G1202R was more common in patients with echinoderm microtubule-associated protein-like 4 (EML4)-ALK v3 fusion, whereas ALK L1196M was more common in v1. TP53 mutant patients were significantly associated with harboring multiple ALK resistance mutations (P = 0.03) and v3+/TP53 mutant patients had the highest rate of multiple ALK resistance mutations. The sequential use of ALK TKI led to an increased incidence of concurrent ALK mutations along the lines of therapies. Alectinib had a lower rate (9%) harboring ALK resistance mutation as first-line ALK TKI compared with crizotinib (36%). ALK compound mutations identified included ALK D1203N/L1196M, ALK G1202R/L1196M, and ALK G1202R/F1174C, which may be lorlatinib resistant. Using paired pretreatment and post-treatment samples, we identified several ALK-independent resistance-related genetic alterations, including PTPRD and CNKN2A/B loss, MYC, MYCN and KRAS amplification, and EGFR19del.ConclusionsSequential postprogression plasma profiling revealed that increased lines of ALK inhibitors can accelerate the accumulation of ALK resistance mutations and may lead to treatment-refractory compound ALK mutations. The selection for optimal first-line TKI is very important to achieve a more efficacious long-term strategy and prevent the emergence of on-target resistance, which may provide guidance for clinical decision making.

Concomitance of a novel RMDN2-ALK fusion and an EML4-ALK fusion in a lung adenocarcinoma

The anaplastic lymphoma kinase (ALK) fusions/rearrangements in non-small cell lung cancer (NSCLC) act as oncogenic driver mutations. ALK tyrosine kinase inhibitors have anti-tumor activities in ALK-positive NSCLC. Although the EML4-ALK fusion is common in NSCLC, concomitance of an additional ALK fusion together with an EML4-ALK fusion is not common. Here, we present a lung adenocarcinoma with two ALK fusions, a novel RMDN2-ALK fusion accompanied by an EML4-ALK fusion, detected by a targeted next generation sequencing assay. The genomic translocation breakpoints of the RMDN2-ALK fusion were mapped to intron 2 for RMDN2 and exon 15 for ALK, and EML4-ALK breakpoints were mapped to intron 13 for EML4 and intron 19 for ALK. ALK break-apart FISH detected multiple ALK rearrangements, a gene fusion panel (NanoString) test confirmed the EML4-ALK fusion, and RNA-sequencing revealed two ALK fusions. The RMDN2 gene locates at the short arm of chromosome 2 between ALK and EML4 genes. The intact ALK kinase domain fused to RMDN2. Genome-wide copy number variants were found in multiple chromosome arms and the short arm of chromosome 2, suggestive of complex rearrangements. Further detailed analyses of breakpoints and copy number variants may shed light on mechanisms of their formation and pathogenesis in lung malignancies.

Ensartinib as Treatment for ALK-Rearranged NSCLC

Ensartinib as Treatment for ALK-Rearranged NSCLC

Retrospective Observational Study of ALK-Inhibitor Therapy Sequencing and Outcomes in Patients with ALK-Positive Non-small Cell Lung Cancer.

BackgroundData are sparse concerning the sequential use of multiple anaplastic lymphoma kinase (ALK) inhibitors for ALK-positive locally advanced or metastatic non-small cell lung cancer (NSCLC).ObjectiveThis study investigated sequencing and outcomes among patients receiving multiple ALK inhibitors.Patients and MethodsThis was a retrospective observational cohort study of adult patients with ALK-positive NSCLC treated with available first- and second-generation ALK inhibitors from 1 September 2011 to 31 December 2017. Duration of therapy (DOT) and overall survival (OS) were assessed with the Kaplan–Meier method. A multivariable linear regression analysis was performed to assess if DOT with a preceding ALK inhibitor was predictive of DOT for subsequent ALK inhibitor treatments.ResultsA total of 410 patients were analyzed: 57% received 1 ALK inhibitor; 35%, 2 ALK inhibitors; and 8%, 3–4 ALK inhibitors. Among those receiving > 1 ALK inhibitor (n = 177), 60% received a crizotinib-led sequence and 39% an alectinib-led sequence. Nearly 60% of the overall population received chemotherapy prior to their first ALK inhibitor. Median OS for the study population was 28 months, 15 months in patients who received 1 ALK inhibitor, 42 months in patients who received 2 ALK inhibitors, and 56 months in patients who received 3–4 ALK inhibitors. Longer DOT of the first ALK inhibitor was associated with increased DOT of the second (p < 0.0001), and longer DOT of the second ALK inhibitor was associated with increased DOT of the third (p < 0.0001).ConclusionsThis study provides initial information on real-world treatment patterns following the introduction of new ALK inhibitors, and supports the use of sequential ALK therapies.

4558 Investigating the functional consequences of anaplastic lymphoma kinase (ALK) mutations arising upon Lorlatinib treatment

OBJECTIVES/GOALS: Neuroblastoma (NB) is an embryonal cancer of the sympathetic nervous system that affects mostly infants and young children. The complex genetic background present across NB patients results in diverse clinical response and difficulty in individualizing therapy. Currently, NB patients undergo a regimen of genotoxic chemotherapeutics, radiation therapy, and new immunotherapy that, while effective, has significant side effects, including excruciating pain. One promising avenue for targeted therapy in neuroblastoma focuses on anaplastic lymphoma kinase (ALK), a cell surface neural receptor tyrosine kinase. We previously identified activating point mutations within the tyrosine kinase domain of ALK as the primary cause of hereditary NB, and we and others subsequently showed that these same alterations are the most common somatic single-nucleotide mutations in the sporadic forms of the disease. Crizotinib, a first-generation small molecule ATP-competitive inhibitor of the ALK tyrosine kinase, showed limited anti-tumor activity in patients with relapsed NB harboring ALK F1174 and F1245 mutations. We have demonstrated that lorlatinib, a novel ATP-competitive ALK inhibitor, overcomes this de novo resistance in preclinical models of ALK-driven NB. Recent clinical trials with lorlatinib in patients with non-small cell lung cancer harboring an ALK fusion, and in patients with NB harboring ALK mutations show the emergence of multiple or compound ALK mutations as a mechanism of resistance. We postulate that these compound mutations disrupt the interaction between and ALK and cause resistance. In this study, we employ a computational approach to model mutated ALK in complex with lorlatinib as well as ATP to understand whether the new mutations alter the affinity or mode of lorlatinib/ATP binding to ALK, and thus cause suboptimal ALK inhibition. METHODS/STUDY POPULATION: We employ methods in computational structural biology and drug design, primarily based on molecular modeling, molecular dynamics (MD), and molecular docking. Based on existing crystal structures of wildtype ALK, we model the mutations and perform MD simulations in order to characterize the activation state of the protein as well as perform ensemble docking calculations to assess the binding affinities and modes in ALK-lorlatinib and ALK-ATP complexes. RESULTS/ANTICIPATED RESULTS: We expect that the compound mutations cause resistance to lorlatinib either by lowering protein affinity for the drug or increasing the affinity for ATP. Alternatively, the compound mutations may disrupt the protein activation state, in which case ALK may no longer be active, and another protein/pathway could be driving the resistance. DISCUSSION/SIGNIFICANCE OF IMPACT: The results of this study will enable the understanding of the mechanism of resistance to lorlatinib and facilitate the design of new ALK inhibitors, or help develop more optimal and mechanism-guided therapies aimed to overcome the resistance.

Treatment Sequencing in Patients with Anaplastic Lymphoma Kinase-Positive Non-Small Cell Lung Cancer in Japan: A Real-World Observational Study.

The anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitor (TKI) alectinib was approved in Japan in 2014 for the treatment of ALK fusion gene-positive advanced non-small cell lung cancer (NSCLC). With the approvals of crizotinib in 2012 and ceritinib in 2017, Japan became the first country with multiple ALK TKIs available for first-line or later use in patients with ALK-positive advanced NSCLC. Here, we collected and evaluated real-world data on ALK TKI clinical usage patterns and sequencing in patients with ALK-positive NSCLC in Japan. This retrospective observational study used the Japanese Medical Data Vision database to analyze data from patients with a confirmed diagnosis of lung cancer who visited a healthcare facility in the database between April 2010 and March 2017, underwent an ALK test, received a prescription for an ALK TKI, and were at least 18years old as of the date of the first ALK TKI prescription. There were no exclusion criteria. Descriptive analyses of demographics, baseline characteristics, ALK TKI treatment patterns and sequences, non-ALK TKI treatments received before, during, and after ALK TKI treatment, and treatment durations were reported. A total of 378 patients met the inclusion criteria and were evaluated in mutually exclusive groups of patients receiving one, two, or three ALK TKIs. The initial ALK TKI prescribed was crizotinib for 52.1% of patients and alectinib for 47.9% of patients; however, the proportion of patients receiving alectinib as the initial ALK TKI increased over time following the Japanese approval of alectinib in 2014. Of the 117 patients who received two or three ALK TKIs, 106 received crizotinib as the first ALK TKI and 11 received alectinib. Before the date of the patient's first ALK TKI prescription, 153 of 378 patients (40.5%) had received chemotherapy. Of 104 patients who discontinued ALK therapy, 46.2% received chemotherapy and 5.8% received immunotherapy as their next treatment. At the time of this analysis, most patients who received more than one ALK TKI received crizotinib as the initial ALK TKI. Additional ALK TKIs have since been approved in Japan as first-line or later therapeutic options for patients with ALK-positive NSCLC, but the optimal sequence of ALK TKI usage remains undetermined. As new data continue to emerge, additional research will be warranted to evaluate ALK TKI sequences that do not include crizotinib as the first therapy in this patient population.

Anaplastic lymphoma kinase fusions as a target for TCR-directed cellular therapies

Abstract Chromosomal rearrangement derived gene fusions with the catalytic domain of anaplastic lymphoma kinase (ALK) drive oncogenesis in several cancers, including in ~5% of non-small-cell lung cancers (NSCLCs). While ALK tyrosine kinase inhibitors (TKIs) have revolutionized the treatment of these patients the majority will develop resistance; novel treatments are required. We hypothesize that the ALK kinase domain may be a suitable target for directed immunotherapy. Full length ALK is normally expressed during fetal development but becomes highly restricted in adults, and anti-ALK immune responses are readily detected in other ALK-fusion+ cancers, correlating with good prognosis. Using peptide pool expansions and T cell activation assays, we have detected numerous anti-ALK T cell responses from normal donors and ALK+ NSCLC patients. These donors express a variety of HLA alleles, and some donors display reactivity to multiple pools spanning the kinase domain, suggestive of common T cell responses to multiple ALK epitopes. Leveraging a high-throughput microfluidic technique to clone and functionally express natively-paired T cell receptor (TCR) genes from these ALK-reactive T cell populations, we are screening for both the exact antigenic peptides and the HLA restrictions of these epitopes. TCRs thus isolated will then be tested against a panel of ALK+/− patient derived and cancer cell lines using in vitro and in vivo models, to assess potential utility in cytotoxic TCR-directed immunotherapies. These patient derived models include those with acquired TKI resistance: by comparing these mutational hotspots with putative epitope sites we expect to find TCRs capable of killing ALK+ cancer cells irrespective of prior treatment.

Lorlatinib for the treatment of ALK-positive metastatic non-small cell lung cancer

ABSTRACTIntroduction: The treatment of lung cancer has changed dramatically with the development of tyrosine kinase inhibitors (TKIs) that target sensitizing somatic (gene) activations including anaplastic lymphoma kinase (ALK)-rearrangements. Despite remarkable initial responses, patients develop progressive disease via various resistance mechanisms, some of which are ALK dependent. Various next-generation ALK TKIs have been developed to improve on central nervous system (CNS) activity and also target the multitude of acquired resistance mechanisms. Of these, lorlatinib has the greatest spectrum of clinical activity against multiple ALK resistance mutations and has also demonstrated promising efficacy in patients with known brain metastases.Areas covered: We discuss the structure, pharmacology and efficacy of lorlatinib and also provide future perspectives in the management of patients with ALK-rearranged non-small cell lung cancer (NSCLC).Expert opinion: Patients invariably develop resistance during treatment with lorlatinib. Unique combinations of ALK resistance mutations may confer sensitivity to alternate ALK TKIs. There is a move toward individualized biomarker-driven treatment strategies to identify the select group of candidates that can benefit from existing therapies.

Front-line treatment of ceritinib improves efficacy over crizotinib for Asian patients with anaplastic lymphoma kinase fusion NSCLC: The role of systemic progression control.

BackgroundApproximately 3%–5% of lung adenocarcinoma is driven by anaplastic lymphoma kinase (ALK) fusion oncogene, whose activity can be suppressed by multiple ALK inhibitors. Crizotinib and ceritinib have demonstrated superior efficacy to platinum‐based chemotherapy as front‐line treatment for patients with ALK‐positive advanced non‐small cell lung cancer (NSCLC). However, the direct comparison between them in the front‐line setting remains lacking.MethodsA total of 48 patients with ALK‐positive, previously untreated advanced NSCLC, who received crizotinib and ceritinib as front‐line treatment were retrospectively investigated. The efficacy and pattern of disease progression were analyzed.ResultsPatients receiving ceritinib treatment were significantly younger than those receiving crizotinib treatment (52.0 vs. 63.0, P = 0.016). The median progression‐free survival (PFS) was significantly longer with ceritinib than with crizotinib treatment (32.3 vs. 12.9 months; log‐rank P = 0.020); the hazard ratio for disease progression or death, 0.27 (95% CI, 0.08–0.90; P = 0.033). An objective response was noted in all patients in the ceritinib group and in 23 patients in the crizotinib group (74.2%; 95% CI, 59.0 to 88.5). The rate of systemic progression was significantly lower over time with ceritinib treatment compared to crizotinib treatment (cause‐specific hazard ratio, 0.21; 95% CI 0.06–0.73; P = 0.014). Serious adverse events were noted in one (2.9%) patient showing elevated liver function in the crizotinib group and three (23.1%) patients showing diarrhea in the ceritinib group. Dose reduction was needed in five out of 13 (38.5%) patients receiving ceritinib treatment.ConclusionCeritinib showed higher efficacy associated with a better control of systemic progression compared to crizotinib for the front‐line treatment of ALK‐positive advanced NSCLCs.

Fluorescence in Situ Hybridization (FISH) for Detecting Anaplastic Lymphoma Kinase (ALK) Rearrangement in Lung Cancer: Clinically Relevant Technical Aspects

In 2011, the Vysis Break Apart ALK fluorescence in situ hybridization (FISH) assay was approved by the United States Food and Drug Administration as a companion diagnostic for detecting ALK rearrangement in lung cancer patients who may benefit from treatment of tyrosine kinase inhibitor therapy. This assay is the current “gold standard”. According to updated ALK testing guidelines from the College of American Pathologists, the International Association for the Study of Lung Cancer and the Association for Molecular Pathology published in 2018, ALK immunohistochemistry is formally an alternative to ALK FISH, and simultaneous detection of multiple hot spots, including, at least, ALK, ROS1, RET, MET, ERBB2, BRAF and KRAS genes is also recommended while performing next generation sequencing (NGS)-based testing. Therefore, ALK status in a specimen can be tested by different methods and platforms, even in the same institution or laboratory. In this review, we discuss several clinically relevant technical aspects of ALK FISH, including pros and cons of the unique two-step (50- to 100-cell) analysis approach employed in the Vysis Break Apart ALK FISH assay, including: the preset cutoff value of ≥15% for a positive result; technical aspects and biology of discordant results obtained by different methods; and incidental findings, such as ALK copy number gain or amplification and co-existent driver mutations. These issues have practical implications for ALK testing in the clinical laboratory following the updated guidelines.

Chinese perspectives on clinical efficacy and safety of alectinib in patients with ALK-positive advanced non-small cell lung cancer.

The incidence of lung cancer is increasing in China, in contrast to trends in Western countries, due to the increasing numbers of smokers and high levels of air pollution. Non-small-cell lung cancer (NSCLC) is the most common form of lung cancer, accounting for approximately 85% of lung cancers. Better understanding of the pathogenesis of NSCLC has led to the identification of multiple genetic mutations and chromosomal translocations such as those in the anaplastic lymphoma kinase (ALK) gene. To facilitate the identification of treatment targets, multiple guidelines (European Society for Medical Oncology, National Comprehensive Cancer Network, and American Society of Clinical Oncology) now recommend screening for genetic factors to help guide treatment decisions. In recent years, multiple ALK inhibitors have been developed to treat NSCLC, including the first-generation tyrosine kinase inhibitor (TKI) crizotinib; second-generation TKIs such as ceritinib, ensartinib, brigatinib, and alectinib; the third-generation TKI lorlatinib; and the fourth-generation TKI repotrectinib. These agents differ in structure, potency, and activity, both systemically and their effects on central nervous system (CNS) metastases. Recently, alectinib was approved in China to treat patients with locally advanced or metastatic NSCLC that were ALK+. Alectinib has demonstrated activity against NSCLC, including metastases within the CNS, with better tolerability than crizotinib. These ALK inhibitors represent significant advances in the treatment of NSCLC and yet patients will likely still exhibit disease progression. Alectinib offers greater potency with greater specificity as well as a better toxicity profile than many other TKIs that are currently available. Here, we review the role of ALK as a therapeutic target in NSCLC, the testing methods for identifying ALK-rearranged NSCLC, and the various TKIs currently being used or explored for treatment in this setting, with a focus on alectinib from a Chinese perspective.

Highly sensitive detection of ALK resistance mutations in plasma using droplet digital PCR

BackgroundOn-target resistance mechanisms found in one-third of patients receiving anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) are secondary ALK mutations in ALK-rearranged non-small cell lung cancer (NSCLC). There are large variations in the resistant mutations, unlike the epithelial growth factor receptor (EGFR) T790 M seen with the use of EGFR-TKIs. Liquid biopsy approaches using cell-free DNA (cfDNA) are used for screening and monitoring of mutations in NSCLC. However, feasible protocol for the simultaneous detection of multiple secondary ALK mutations using droplet digital PCR (ddPCR) has not been developed. An efficient strategy using cfDNA in cancer diagnostics, the development of more accurate and cost-effective tools to identify informative multiple secondary ALK mutations is clinically required.MethodsTo establish a feasible assay to monitor ALK-TKI resistance mutations, we first evaluated the feasibility of ddPCR-based screening for cfDNA mutation detection of 10 distinct secondary ALK mutations. Positive samples were then re-analyzed using mutation-specific probes to track the growth of mutation clones with a high sensitivity.ResultsBlood samples from seven ALK-positive patients were analyzed using the ddPCR protocol. Secondary G1202R ALK mutations were identified in 2 of 7 patients by the screening assay. Using the mutation-specific probes, monitoring the resistant clone during the clinical course of the disease was well demonstrated in each of the patients.ConclusionThe protocol for ddPCR-based liquid biopsy has a feasibility for the screening of secondary ALK-TKI resistance mutations and offers a tool for a cost-effective monitoring of progression in NSCLC.

Brigatinib for treatment of anaplastic lymphoma kinase-rearranged metastatic non-small cell lung cancer

ABSTRACTIntroduction: Crizotinib has been approved as a first-line treatment for patients with anaplastic lymphoma kinase (ALK)-rearranged advanced non-small-cell lung cancer (NSCLC). However, the majority of patients treated with crizotinib experience progression within 1 year, and the central nervous system (CNS) is the most common site of progression. Brigatinib, a potent and selective ALK inhibitor that can inhibit multiple crizotinib-resistant ALK mutants, has shown superior efficacy in advanced ALK-rearranged NSCLC, including in patients with CNS metastases.Areas covered: We reviewed the characteristics of brigatinib, and its clinical efficacy and safety have been demonstrated in previous pivotal studies.Expert opinion: Brigatinb was recently approved for use in ALK-rearranged NSCLC with acquired resistance to crizotinib as first-line treatment. Moreover, brigatinib is highly active in patients with CNS metastasis. The major concern about pulmonary adverse events was resolved with changes in treatment schedule. The mechanisms of resistance to brigatinib and the sequence of treatment with other ALK inhibitors are unresolved issues.

Drug resistance in anaplastic lymphoma kinase-rearranged lung cancer.

The anaplastic lymphoma kinase (ALK) gene encodes a receptor tyrosine kinase, and many kinds of ALK fusion genes have been found in a variety of carcinomas. There is almost no detectable expression of ALK in adults. However, through ALK gene rearrangement, the resultant ALK fusion protein is aberrantly overexpressed and dimerized through the oligomerization domains, such as the coiled‐coil domain, in the fusion partner that induces abnormal constitutive activation of ALK tyrosine kinase. This results in dysregulated cell proliferation. ALK gene rearrangement has been observed in 3%‐5% of non‐small‐cell lung cancers, and multiple ALK inhibitors have been developed for the treatment of ALK‐positive lung cancer. Among those inhibitors, in Japan, 3 (4 in the USA) ALK tyrosine kinase inhibitors (TKIs) have been approved and are currently used in clinics. All of the currently approved ALK‐TKIs have been shown to induce marked tumor regression in ALK‐rearranged non‐small‐cell lung cancer; however, tumors inevitably relapse because of acquired resistance within a few years. This review focuses on ALK‐TKIs, their resistance mechanisms, and the potential therapeutic strategies to overcome resistance.

Treatment of ALK-rearranged non-small cell lung cancer: A review of the landscape and approach to emerging patterns of treatment resistance in the Australian context.

Since the identification of anaplastic lymphoma kinase (ALK) gene rearrangements in non-small cell lung cancer (NSCLC) in 2005, the treatment of ALK-rearranged NSCLC (ALK+ NSCLC) has evolved at a rapid pace. This molecularly distinct subset of NSCLC has uniquely important biology, clinicopathologic features and mechanisms of drug resistance which impact on the choice of treatment for a patient with this disease. There are multiple ALK tyrosine kinase inhibitors now available in clinical practice with efficacy data continuing to emerge and guide the optimal treatment algorithm. A detailed search of medical databases and clinical trial registries was conducted to capture all relevant articles on this topic enabling an updated detailed overview of the landscape of management of ALK-rearranged NSCLC.

Sequential Use of Anaplastic Lymphoma Kinase Inhibitors in Japanese Patients With ALK-Rearranged Non–Small-Cell Lung Cancer: A Retrospective Analysis

BackgroundSecond-generation anaplastic lymphoma kinase (ALK) inhibitors, such as alectinib and ceritinib, have recently been approved for treatment of ALK-rearranged non–small-cell lung cancer (NSCLC). An optimal strategy for using 2 or more ALK inhibitors has not been established. We sought to investigate the clinical impact of sequential use of ALK inhibitors on these tumors in clinical practice. Patients and MethodsPatients with ALK-rearranged NSCLC treated from May 2010 to January 2016 at the National Cancer Center Hospital were identified, and their outcomes were evaluated retrospectively. ResultsFifty-nine patients with ALK-rearranged NSCLC had been treated and 37 cases were assessable. Twenty-six received crizotinib, 21 received alectinib, and 13 (35.1%) received crizotinib followed by alectinib. Response rates and median progression-free survival (PFS) on crizotinib and alectinib (after crizotinib failure) were 53.8% (95% confidence interval [CI], 26.7%-80.9%) and 38.4% (95% CI, 12.0%-64.9%), and 10.7 (95% CI, 5.3-14.7) months and 16.6 (95% CI, 2.9-not calculable), respectively. The median PFS of patients on sequential therapy was 35.2 months (95% CI, 12.7 months-not calculable). The 5-year survival rate of ALK-rearranged patients who received 2 sequential ALK inhibitors from diagnosis was 77.8% (95% CI, 36.5%-94.0%). ConclusionThe combined PFS and 5-year survival rates in patients who received sequential ALK inhibitors were encouraging. Making full use of multiple ALK inhibitors might be important to prolonging survival in patients with ALK-rearranged NSCLC.