ALK-rearranged Non-small Cell Lung Cancer Research Articles

Ensartinib as Treatment for ALK-Rearranged NSCLC

Ensartinib as Treatment for ALK-Rearranged NSCLC

1253P Clinical relevance of immune factors beyond CD8+T cells and mutation status of EGFR and ALK in patients with non-small cell lung cancer

EGFR-mutated or ALK-rearranged non-small cell lung cancer (NSCLC) showed poor response to therapy with immune checkpoint inhibitors (ICI), with infiltration of CD8+T cells and PD-L1 expression considered as an explanation. However, even for patients selected by PD-L1 or CD8+ T cells, the clinical benefit is also limited suggesting that there are additional factors to be taken into account. We evaluated immune status of the tumour microenvironment to understand better the different response to ICI therapy among patients with EGFR mutations or ALK-rearranged NSCLC.

Abstract 4479: Immune exhaustion of tumor microenvironment mediates crizotinib resistance in ALK rearranged advanced non small cell lung cancer

Abstract Introduction: Previous study showed the correlation between immune tumor microenvironment and the efficacy of checkpoint inhibitor in non-small cell lung cancer (NSCLC). This study evaluated whether biomarkers for immune tumor microenvironment including programmed death ligand 1 (PD-L1), cluster of differentiation 8 (CD8), Granzyme B (GZMB) and T cell receptor (TCR) could predict the treatment response to the first-line crizotinib of patients with ALK-rearranged non-small cell lung cancer (NSCLC). Methods: We retrospectively evaluated patients with advanced NSCLC who received crizotinib at Hunan Cancer Hospital between January 2016 and December 2018. The patients' baseline expression of PD-L1, CD8 and GZMB was evaluated in one slide using immunofluorescence. TCR was also evaluated with paired blood samples simultaneously. Results: All the 108 eligible patients were stratified according to their expression profile into PD-L1+/CD8+/GZMB+ (n=21), PD-L1-/CD8+/GZMB+ (n=42), PD-L1+/CD8-/GZMB- (n=23), and PD-L1-/CD8-/GZMB- (n=22) group. Patients with strong PD-L1 expression have a significantly inferior objective response rate (36.5% versus 72.2%, p = 0.002), and shorter progression-free survival (PFS) (5.6 versus 16.5 months, p < 0.001) as compared to patients with weak or negative PD-L1 expression. Among the four groups, we found patients with PD-L1-/CD8+/GZMB+ had the best response (85.7% versus 26%, p=?), while PD-L1+/CD8-/GZMB- showed primary resistance to crizotinib had the worse outcomes (4.6 versus 18 months, p < 0.001). Furthermore, for TCR analysis, the counts of TCR and Shannon index was strongly correlated with longer PFS for crizotinib treatment (20.6 versus 8.2months, p < 0.001; 19.3 versus 6.1 months, p < 0.001, respectively). However, the clonality acts as poor predictive marker with worse PFS (6.8 versus 18.2 months, p < 0.001). Finally, three patients with de novo resistance to crizotinib experienced a favorable response to anti-PD-1 therapy. Conclusions: This study revealed immune exhaustion for tumor microenvironment as a poor predictive marker in first-line crizotinib-treated ALK-rearranged non-small cell lung cancer. The findings indicate the reshaping of an inflamed immune phenotype characterized by PD-L1, CD8, GZMB, and TCR expression and suggest potential therapeutic sensitivity to PD-1 blockade. Citation Format: Yongchang Zhang. Immune exhaustion of tumor microenvironment mediates crizotinib resistance in ALK rearranged advanced 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 4479.

Spontaneous regression of ALK fusion protein-positive non-small cell lung carcinoma: a case report and review of the literature

BackgroundALK-rearrangement is observed in < 5% non-small cell lung cancer (NSCLC) cases and prior to the advent of oral tyrosine kinase inhibitors, the natural history of oncogenic NSCLC was typically poor. Literature relating to regression of treatment-naïve NSCLC is limited, and regression without treatment has not been noted in the ALK-rearranged sub-population.Case presentationA 76 year old ‘never smoker’ female with an ALK-rearranged left upper lobe T2 N0 NSCLC experienced a stroke following elective DC cardioversion for new atrial fibrillation. Following a good recovery, updated imaging demonstrated complete regression of the left upper lobe lesion and a reduction of the previously documented mediastinal lymph node. Remaining atelectasis was non-avid on repeat PET-CT imaging, 8 months from the baseline PET-CT. When the patient developed new symptoms 6 months later a further PET-CT demonstrated FDG-avid local recurrence. She completed 55 Gy in 20 fractions but at 18 months post-radiotherapy there was radiological progression in the lungs with new pulmonary metastases and effusion and new bone metastases. Owing to poor performance status, she was not considered fit for targeted therapy and died 5 months later.ConclusionAll reported cases of spontaneous regression in lung cancer have been collated within. Documented precipitants of spontaneous regression across tumour types include biopsy and immune reconstitution; stroke has not been reported previously. The favourable response achieved with radical radiotherapy alone in this unusual case of indolent oncogenic NSCLC reinforces the applicability of radiotherapy in locally advanced ALK-rearranged tumours, in cases not behaving aggressively. As a common embolic event affecting the neurological and pulmonary vasculature is less likely, an immune-mediated mechanism may underpin the phenomenon described in this patient, implying that hitherto unharnessed principles of immuno-oncology may have relevance in oncogenic NSCLC. Alternatively, high electrical voltage applied percutaneously adjacent to the tumour during cardioversion in this patient may have induced local tumour cell lethality.

Leptomeningeal Metastases in Non-small Cell Lung Cancer: Optimal Systemic Management in NSCLC With and Without Driver Mutations

As a devastating complication of non-small cell lung cancer (NSCLC), the incidence of leptomeningeal metastasis (LM) is rising, largely due to overall longer survival of NSCLC, especially in patients with targetable molecular driver mutations. There is no clear consensus on the optimal management of LM. This review will cover recent advances in diagnosis, monitoring, and treatment of LM in NSCLC. In LM without oncogene drivers, systemic chemotherapy, intrathecal therapy, and radiation have modestly improved the clinical outcomes. Emerging data have also suggested encouraging activity of immunotherapy. At the same time, in LM with sensitizing EGFR mutations, osimertinib should be considered regardless of T790M status. Pulse erlotinib, afatinib, and newer agents with improved CNS penetration have also shown benefits. Moreover, accumulating evidences support potential benefits of molecularly targeted therapy in ALK-rearranged and other oncogene-driven NSCLC with LM. Future studies are warranted to better define the underlying mechanism, to optimize the clinical management, and to improve patient outcomes.

ALK-Rearranged Non-Small Cell Lung Cancer in 2020: Real-World Triumphs in an Era of Multigeneration ALK-Inhibitor Sequencing Informed by Drug Resistance Profiling.

Since its discovery in 2007, we have seen the lives of patients diagnosed with advanced anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancers (NSCLC) transform with the advent of molecular therapies with first-, second-, and third-generation ALK inhibitors now available in the clinic. Despite great gains in patient survival now measured in years and preserved quality of life with targeted therapies, drug resistance is unfortunately inevitably encountered in this rare and unique molecular subset of lung cancer, and patients will eventually succumb to the disease. As these patients are often young, fit, and never smokers, the clinical and scientific communities have aligned to expedite drug development and access. Drug resistance profiling and further strategies are being explored through clinical trials, including the evaluation of specific drug sequencing and combinations to overcome such resistance and promote patient longevity. The cases of this report focus on precision medicine and aim to portray the pertinent aspects to consider when treating ALK-rearranged NSCLC in 2020, an ever-shifting space. By way of case examples, this report offers valuable information to the treating clinician, including the evolution of systemic treatments and the management of oligo-progression and multisite drug resistance. With the maturation of real-world data, we are fortunate to be experiencing quality and length of life for patients with this disease surpassing prior expectations in advanced lung cancer. KEY POINTS: This report focuses on the importance of genetic analysis of serial biopsies to capture the dynamic therapeutic vulnerabilities of a patient's tumor, providing a perspective on the complexity of ALK tyrosine kinase inhibitor (ALKi) treatment sequencing. These case examples contribute to the literature on ALK-rearranged and oncogene addicted non-small cell lung cancer (NSCLC), providing a framework for care in the clinic. In oligo-progressive disease, local ablative therapy and continuation of ALKi postprogression should be considered with potential for sustained disease control. ALK G1202R kinase domain mutations (KDM), highly prevalent at resistance to second-generation ALKi resistances, may emerge in non-EML4-ALK variant 3 cases and is sensitive to third-generation lorlatinib. When in compound with one or more ALK KDMs, resistance to lorlatinib is expected. In the case of rampantly progressive disease, rebiopsy and redefining biology in a timely manner may be informative.

Optimal Care for Patients with Anaplastic Lymphoma Kinase (ALK)-Positive Non-Small Cell Lung Cancer: A Review on the Role and Utility of ALK Inhibitors.

The treatment of advanced non–small-cell lung cancer (NSCLC) has undergone a paradigm shift in the last decade. Molecular characterization of the disease has led to the rapid development of personalized medicine and swift delivery of targeted therapies to patients. The discovery of the anaplastic lymphoma kinase (ALK) gene in patients with NSCLC has resulted in rapid bench–bedside transition of several active drugs, with several others currently in clinical trials. After the first-generation ALK inhibitor crizotinib, next-generation ALK inhibitors have entered clinical applications for ALK-rearranged NSCLC. Ceritinib, alectinib, and brigatinib have all received approval for ALK-positive patients who have failed prior crizotinib, as well as first-line therapy in treatment-naïve patients based on favorable efficacy. Most recently, lorlatinib, a potent, newer-generation ALK inhibitor, has been approved as second- or third-line treatment. These advances have led to better patient outcomes, but concurrently have led to several crucial unanswered questions about optimal care for ALK-positive NSCLC patients. The ultimate acquisition of resistance to ALK-inhibitor therapy poses a challenge to ongoing research efforts, in addition to the routine management of these patients in the clinic. This review provides a summary of the clinical development of crizotinib, ceritinib, alectinib, brigatinib, and lorlatinib and highlights current management paradigms, current and evolving clinical information, emerging clinical decision-making and sequencing of therapy in advanced, metastatic, or recurrent ALK-positive NSCLC.

Pharmacological and clinical properties of lorlatinib in the treatment of ALK-rearranged advanced non-small cell lung cancer

ABSTRACT Introduction Approximately 3–7% of advanced non-small cell lung cancers (NSCLC) are driven by an anaplastic lymphoma kinase (ALK) rearrangement. Crizotinib, ceritinib, alectinib, and brigatinib are active ALK inhibitors (ALKi) used to treat this oncogene-driven subset of NSCLC. Resistance occurs with time to ALKi and new therapeutics are being developed. Lorlatinib is an efficacious third-generation ALKi with an ability to overcome resistance mutations that develop with first- or second-generation ALKi. Areas covered Herein, the authors review the mechanism of action, pharmacokinetics, pharmacodynamics, clinical efficacy, and safety of lorlatinib and provide their future perspectives on this drug. Expert commentary Lorlatinib is a potent ALK and ROS-1 inhibitor that also has activity against many acquired ALK resistance mutations. Clinical trials show the robust systemic and intracranial anti-tumor activity of lorlatinib in ALK rearranged advanced NSCLC. Adverse events of lorlatinib are unique and manageable. These include hypocholesteremia, hypertriglyceridemia, edema, cognitive effects, weight gain, and diarrhea. Loratinib will play an increasing role in the management of ALK-rearranged NSCLC with the optimal sequencing of ALKi undergoing further research.

Acquired Resistance to Alectinib in ALK-Rearranged Lung Cancer due to ABCC11/MRP8 Overexpression in a Clinically Paired Resistance Model.

Alectinib is used as a first-line treatment for anaplastic lymphoma kinase (ALK)-rearranged non-small cell lung cancer (NSCLC). Whereas other ALK inhibitors have been reported to be involved in resistance to ATP-binding cassette (ABC) transporters, no data are available regarding the association between resistance to alectinib and ABC-transporters. To investigate whether ABC-transporters contribute to alectinib resistance, ABC-transporter expression in alectinib-resistant cell lines derived from a patient with ALK-rearranged NSCLC and from H2228 lung cancer cells was evaluated and compared with that in each parent cell type. ATP-binding cassette subfamily C member 11 (ABCC11) expression was significantly increased in alectinib-resistant cell lines compared with that in alectinib-sensitive lines. ABCC11 inhibition increased sensitivity to alectinib in vitro ABCC11-overexpressing cells were established by transfection of an ABCC11 expression vector into H2228 cells, while control cells were established by transfecting H2228 cells with an empty vector. ABCC11-overexpressing cells exhibited decreased sensitivity to alectinib compared with that of control cells in vitro Moreover, the tumor growth rate following alectinib treatment was higher in ABCC11-overexpressing cells than that in control cells in vivo In addition, the intracellular alectinib concentration following exposure to 100 nmol/L alectinib was significantly lower in the ABCC11-overexpressing cell line compared with that in control cells. This is the first preclinical evidence showing that ABCC11 expression may be involved in acquired resistance to alectinib.

In vitro and in vivo synergistic efficacy of ceritinib combined with programmed cell death ligand-1 inhibitor in anaplastic lymphoma kinase-rearranged non-small-cell lung cancer.

Both ceritinib (CER) and programmed cell death (PD)‐1/PD ligand‐1 (PD‐L1) have brought significant breakthroughs for anaplastic lymphoma kinase (ALK)‐rearranged non‐small‐cell lung cancer (NSCLC). However, the overall clinical efficacy of either CER or PD‐1/PD‐L1 inhibitor monotherapy has been limited to a large extent. In addition, the antitumor effect of combined CER and PD‐L1 inhibitor in ALK‐rearranged NSCLC is not fully understood. In H2228 cells, we examined the tumor killing effect of CER plus PD‐L1 inhibitor in vitro by quantitative RT‐PCR, flow cytometry, ELISA, western blot analysis, PBMC coculture system, and plasmid and transfection experiments. A Ba/F3 (EML4‐ALK‐WT) xenograft mouse model was also utilized to further evaluate the synergistic anticancer effects of CER and PD‐L1 inhibitor in vivo. The coculture system of PBMCs with H2228 cells promotes the expression of PD‐L1 and phospho‐ERK, and combined treatments facilitate lymphocyte proliferation and activation, inhibit PD‐L1 expression, and enhance lymphocyte cytotoxicity and cell death. In the in vivo NSCLC xenograft model, the volumes of tumors treated with CER and PD‐L1 inhibitor in combination were significantly smaller than those treated with CER or PD‐L1 alone. The relative tumor growth inhibitions were 84.9%, 20.0%, and 91.9% for CER, PD‐L1 inhibitor, and CER plus PD‐L1 groups, respectively. Ceritinib could synergize with PD‐1/PD‐L1 blockade to yield enhanced antitumor responses along with favorable tolerability of adverse effects. Ceritinib and PD‐L1 inhibitor combined produced a synergistic antineoplastic efficacy in vitro and in vivo, which provides a key insight and proof of principle for evaluating CER plus PD‐L1 blockade as combination therapy in clinical therapeutic practice.

SAF-189s in previously treated patients with advanced ALK-rearranged non-small cell lung cancer (NSCLC): Results from the dose-finding portion in a single-arm, first-in-human phase I/II study.

e21689 Background: Patients(pts) with ALK-rearranged non-small cell lung cancer (NSCLC) are sensitive but progress in 8–11 months with treatment of ALK inhibitor crizotinib, with leading progression in brain metastasis. SAF-189s is a novel and selective ALK inhibitor, can penetrate through blood brain barrier, and overcome multiple resistance mutation. This study aimed to explore the safety, efficacy, and pharmacokinetic properties of SAF-189s in patients with advanced ALK-rearranged NSCLC. Methods: In this multicenter I/II study, SAF-189s was orally administered under fasting condition at doses ranging from 20–210 mg once daily in a 21-day cycle to 36 pts with advanced ALK-positive NSCLC who had failed to prior systemic therapy. In this analysis report, anti-tumor activity of SAF-189s was evaluated in 34 pts received 40(n = 6), 80(n = 8), 120(n = 8), 160(n = 9) and 210(n = 3) mg doses daily. Safety was evaluated in all 36 pts who received ≥1 treatment. This study is registered with clinicaltrials.gov, NCT04237805. Results: 36 pts were enrolled in total, 22 pts had CNS metastases at baseline and 26 pts had progressed to prior TKIs therapy. There was no treatment-related SAE among the 36 pts. The most common drug-related events were nausea (14 [38.9%] of 36 pts), vomiting (10[27.8%] of 36 pts), QT prolongation (9 [25.0%] of 36 pts), sinus bradycardia (7 [19.4%] of 36 pts), ALT increase (10 [27.8%] of 36 pts), diarrhea (6 [16.7%] of 36 pts). Only one DLT of grade 3 blood glucose increase occurred at 210 mg out of the first 3 pts, so another 3 pts will be enrolled to determine RP2D/MTD. SAF-189s had shown response in the starting dose of 20mg, with 1of 2 pts achieving partial response (PR) over 43 cycles until clinical data cut off. All 34 pts in efficacy analysis set had achieved tumor shrinkage, with 17 confirmed PR (50%) (95% CI, 32.4–67.6%) and 4 unconfirmed PR (11.7%). 11 (45.8%) pts had confirmed PR among 24 pts who had failed to Crizotinib or Ceritinib and 10 (47.6%) pts had confirmed PR among 21pts who had CNS metastases. PFS data is pre-mature, with only median PFS of the 80 mg cohort being inferred as 19.42 months. Conclusions: In the dose-escalation portion of this study, SAF-189s was safe, very tolerable, and demonstrated both systemic and intracranial activity in pts with advanced ALK-positive NSCLC who had failed to at least 1 prior systemic therapy. Therefore, this study warrants further investigation to prove SAF-189s as an effective therapeutic option for pts who have ALK+ NSCLC. Clinical trial information: NCT04237805.

Longitudinal monitoring by next generation sequencing of plasma cell-free DNA in ALK-rearranged non-small cell lung cancer (NSCLC) patients treated with ALK tyrosine kinase inhibitors.

9603 Background: Patients with anaplastic lymphoma kinase-rearranged (ALK+) NSCLC inevitably acquire resistance to ALK inhibitors. We hypothesized that longitudinal monitoring of cell-free plasma DNA (cfDNA) next generation sequencing (NGS) could predict the response and resistance of TKI therapy in ALK+NSCLC Methods: Patients with ALK+ advanced NSCLC determined by standard tissue testing and planned for TKI therapy were prospectively recruited. Plasma was collected before therapy (n = 92), two months post-therapy (n = 58), and at progression (n = 35). Plasma DNA NGS analysis was done retrospectively by Guardant360. Results: From April 2015 to July 2019, 92 patients enrolled; 81 (88.0%) received ALK TKI as first-line (crizotinib, n = 59; alectinib, n = 22), 10 (10.9%) received TKI as second-line (alectinib, n = 6; crizotinib, n = 2; ceritinib, n = 1; brigatinib, n = 1), and 1 (1.1%) was treated in third-line (lorlatinib). At the cut-off date of January 28, 2020, 56 of 92 patients had disease progression. Circulating tumor DNA (ctDNA) was detected in 69 baseline samples (75%); among these were 43 ALK fusions (62.3%) and 1 ALK G1202R without fusion (1.4%). Fusions included EML4-ALK v1 (n = 19), EML4-ALK v3 (n = 14), CLTC-ALK (n = 1), TPM3-ALK (n = 1), GCC2-ALK/CLIP4-ALK (n = 1), and other EML4-ALK fusions (n = 7). Eight patients developed ALK resistance mutations after crizotinib therapy: L1196M (n = 5), G1269A (n = 1), G1202R (n = 1), and co-occurring F1174L, G1202R, and G1269A (n = 1). Two patients developed ALK resistance mutations after ceritinib: G1202R (n = 1), and co-occurring G1202R and T1151R (n = 1). The absence of detectable ctDNA at baseline was associated with longer progression-free survival (PFS; median 36.1 vs 11.6 months, HR 0.432, p = 0.004) and overall survival (OS; median not reached vs 27.9 months, HR 0.418, p = 0.034). Patients with clearance of ctDNA at two months (n = 29) had significantly longer PFS (median 25.4 vs 13.9 months, HR 0.343, p = 0.030) and OS (median not reached vs 25.7 months, HR 0.173, p = 0.035) than those without clearance (n = 22). Patients with co-occurring TP53 alterations and ALK fusions at baseline (n = 9) showed shorter PFS (median 7.0 vs 12.5 months, HR 3.596, p = 0.0154) than those without TP53 alterations (n = 35). Conclusions: NGS of cell-free plasma DNA is useful not only for the detection of ALK fusions and resistance mutations but also for assessing prognosis and monitoring the dynamic changes of genomic alterations in ALK+ NSCLC treated with ALK TKI.

Efficacy and safety of ceritinib in anaplastic lymphoma kinase-rearranged non-small cell lung cancer: A systematic review and meta-analysis.

What is known and objectiveCeritinib is a new, oral, potent and selective second‐generation anaplastic lymphoma kinase (ALK) inhibitor approved by the Food and Drug Administration of the United States in April 2014. It is active in crizotinib‐resistant patients, especially in patients with non‐small cell lung cancer (NSCLC) and brain metastasis. The aim of this study was to analyse the effects and side effects of ceritinib in ALK‐rearranged NSCLC.MethodsWe searched articles published from January 1980 to March 2019 in PubMed, EMBASE, Cochrane Library and Web of Science. The pooled estimate and 95% CI were calculated with DerSimonian‐Laird method and the random effect model.Results and discussionFrom 15 articles, 2,598 patients were included in the meta‐analysis. Eleven studies reported the ORR, and the DCR was presented in 10 studies. The ORR and DCR of ceritinib were 0.48 (95% CI, 0.39‐0.57) and 0.76 (95% CI, 0.69‐0.82), respectively. The PFS and OS were presented in nine and three eligible studies, respectively. The PFS and OS of ceritinib were 7.26 months (95% CI, 5.10‐9.43) and 18.73 months (95% CI; 14.59‐22.87). These results suggested that ceritinib can effectively treat patients with ALK‐rearranged NSCLC. Diarrhoea, nausea and vomiting were the three most common AEs and occurred in 69% (95% CI 51.7‐87.1%), 66% (95% CI 47.0‐85.8%) and 51% (95% CI 35.9‐66.8%) of patients, respectively. Considering serious gastrointestinal AEs, antiemetic and antidiarrhoeal drugs should be considered to improve a patient's tolerance to ceritinib.What is new and conclusionCeritinib is effective in the treatment of patients with ALK‐rearranged NSCLC with crizotinib resistance. The DCR was up to 76%, and PFS was extended to 7.6 months. The AEs were acceptable.

Molecular testing of metastatic non-small cell lung cancer in the Asia-Pacific region.

Molecular testing of metastatic non-small cell lung cancer in the Asia-Pacific region.

Efficacy and safety of ALK inhibitors in ALK-rearranged non-small cell lung cancer: A systematic review and meta-analysis

ObjectivesNo overall survival (OS) benefit has been reported from a mature randomized trial with the use of ALK inhibitors. We conducted a systematic review and meta-analysis to assess the efficacy of ALK inhibitors compared to chemotherapy (ALK vs. chemo) and 2nd generation ALK inhibitors compared to 1 st generation ALK inhibitors (ALK-2 G vs. ALK-1 G). MethodsThe electronic databases Medline (PubMed), EMBASE, and the Cochrane Database of Systematic Reviews were searched for relevant randomized trials. Pooled hazard ratios (HR) for OS and progression free survival (PFS), and pooled risk ratios for objective response rates (ORR) and toxicity were meta-analyzed using the generic inverse variance and the Mantel-Haenszel methods. To account for between-studies heterogeneity, random-effect models were used. Subgroup analyses compared PFS by gender, smoking status, brain metastases, race and age. ResultsSix trials were included in the analysis of ALK vs. chemo and four in the analysis of ALK-2 G vs. ALK-1 G. Treatment with ALK inhibitors improved OS compared to chemotherapy (HR: 0.84, 95 %CI 0.72−0.97) while a trend toward a better OS was seen with ALK-2 G vs. ALK-1 G (HR: 0.66, 95 %CI 0.43–1.02). PFS was improved with ALK vs. chemo and ALK-2 G vs. ALK-1 G (HR: 0.44, 95 %CI 0.35−0.54 and HR: 0.38, 95 %CI-0.29−0.51, respectively). ORR was improved with ALK vs. chemo and ALK-2 G vs. ALK-1 G. No difference in toxicity was observed. ConclusionsThis meta-analysis is the first, to our knowledge, to report an OS and PFS benefit with the use of ALK inhibitors compared to chemotherapy from randomized trial data. A trend toward a better OS was also seen with ALK-2 G vs. ALK-1 G and this is likely because of crossover effects and limited OS follow-up. Longer follow up and further research are warranted to directly compare ALK inhibitor sequences and to understand the outcomes of second generation ALK inhibitors as initial therapy.

Monomerization of ALK Fusion Proteins as a Therapeutic Strategy in ALK-Rearranged Non-small Cell Lung Cancers.

Objective: Oncogenic echinoderm microtubule-associated protein-like 4 (EML4)-anaplastic lymphoma kinase (ALK) (EML4-ALK) fusion proteins found in non-small cell lung cancers (NSCLC) are constitutively phosphorylated and activated by dimerization via the coiled-coil domain (cc) within EML4. Here, we investigated whether disruption of ALK fusion protein oligomerization via competitive cc mimetic compounds could be a therapeutic strategy for EML4-ALK NSCLC.Methods: A Ba/F3 cell model was created that expressed an ALK intracellular domain in which the dimer/monomer state is ligand-regulated. This novel cell model was used to investigate the effect of disrupting ALK fusion protein oligomerization on tumor cell growth in vitro and in vivo using nude mice. Subsequently, the antiproliferative effects of endogenous cc domain co-expression and mimetic cc peptides were assayed in EML4-ALK cancer cell lines.Results: Cells induced to express monomeric ALK in vitro did not survive. When transplanted into mice, induction of monomers abrogated tumor formation. Using a fluorescent protein system to quantify protein-protein interactions of EML4-ALK and EML4cc, we demonstrated that co-expression of EML4cc suppressed EML4-ALK assembly concomitant with decreasing the rate of tumor growth in vitro and in vivo. In EML4-ALK cancer cell lines, administration of synthetic EML4cc peptide elicited a decrease of phosphorylation of ALK leading to reduction in tumor cell growth.Conclusions: Our findings support the monomerization of ALK fusion proteins using EML4cc peptides for competitive inhibition of dimerization as a promising therapeutic strategy for EML4-ALK NSCLC. Further studies are warranted to explore the use of specific cc peptide as a therapeutic option for other lung cancers harboring driver fusion genes containing a cc or oligomerization domain within the fusion partner.

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.

Tumor Volume Analysis as a Predictive Marker for Prolonged Survival in Anaplastic Lymphoma Kinase-rearranged Advanced Non-Small Cell Lung Cancer Patients Treated With Crizotinib.

Targeted inhibition of anaplastic lymphoma kinase (ALK) has been widely used for the treatment of advanced non-small cell lung cancer (NSCLC) with ALK rearrangements. We performed tumor volume analysis of ALK-rearranged advanced NSCLC treated with crizotinib to identify an early predictive marker for prolonged survival. Cases of 42 patients with ALK-rearranged advanced NSCLC (16 men, 26 women; median age: 55.7 y) treated with crizotinib as their first ALK-directed therapy were retrospectively studied. Tumor volume measurements of dominant lung lesions were performed on baseline computed tomography and follow-up computed tomography at 8 weeks of therapy. The relationships between the 8-week volume change (%) and overall survival (OS) were investigated. The 8-week tumor volume change ranged from -99.3% to 117.5% (median: -57.7%). Using the 25th percentile of the 8-week volume change of -74%, 11 patients with >74% volume decrease at 8 weeks had a significantly longer OS compared with 31 patients with ≤74% decrease (median OS: 92.0 vs. 22.8 mo; P=0.0048). In multivariable analyses using Cox proportional hazards models, the 8-week volume decrease of >74% was significantly associated with longer OS (hazard ratio=0.14, 95% confidence interval: 0.03-0.59; Cox P=0.008) after adjusting for tumor stage (stage IV vs. recurrent NSCLC, hazard ratio=5.6, 95% confidence interval: 1.29-24.3; P=0.02). The 8-week tumor volume decrease of >74% is significantly associated with longer OS in patients with ALK-rearranged NSCLC treated with crizotinib.

B07 Mechanisms of Alectinib Resistance in a Leptomeningeal Carcinomatosis of EML4-ALK Lung Cancer and Its Circumvention by EGR-TKIs

Central nervous system (CNS) metastasis, such as brain metastasis and leptomeningeal carcinomatosis (LMC), occurs in 20–40% of all patients with cancer. Anaplastic lymphoma kinase (ALK) is a clinically validated drug target, and ALK rearrangements are found in approximately 3-5% of non-small cell lung cancer (NSCLC). ALK tyrosine kinase inhibitor (TKI) shows dramatic clinical efficacy in ALK-rearranged NSCLC patients, and the second-generation ALK-TKI alectinib is effective against CNS metastasis of ALK-rearranged NSCLC. However, the patients with ALK-rearrangement acquire resistance to alectinib over time and develop recurrent LMC metastasis. This study aimed to clarify the mechanism of resistance to alectinib in LMC and seek a novel therapeutic strategy. Alectinib-resistant cell line (A925L/AR) was established by continuous treatment with alectinib in the LMC mouse model inoculated with the alectinib-sensitive human lung cancer cell line, A925LPE3, which harbors the EML4-ALK gene fusion. The tumor level was measured by in vivo imaging system. To clarify the mechanism of alectinib resistance, tumor cell culture supernatants, patient cerebrospinal fluid (CSF), and patient serum were measured using ELISA kits for EGFR ligands. A925L/AR cells were moderately resistant to various ALK-TKIs, such as alectinib, crizotinib, ceritinib, and lorlatinib, compared with parental cells in vitro. A925L/AR cells acquired resistance through epidermal growth factor receptor (EGFR) activation due to overexpression of its ligand, amphiregulin, via inhibited expression of microRNA 449-a. EGFR-TKIs and anti-EGFR antibodies resensitized A925L/AR cells to alectinib in vitro. In the LMC model with A925L/AR cells, combined treatment with alectinib and an EGFR-TKI, such as erlotinib and osimertinib, successfully controlled LMC progression. Imaging mass spectrometry showed accumulation of EGFR-TKIs in the tumor lesions. Moreover, notably high amphiregulin levels were detected in the cerebrospinal fluid from ALK-rearranged NSCLC patients with alectinib-resistant LMC compared with those in EGFR-mutated NSCLC patients with EGFR-TKI-resistant LMC or patients without LMC. We demonstrated that EML4-ALK lung cancer cells acquired moderate resistance to alectinib in the leptomeningeal space due to amphiregulin-triggered EGFR activation. Moreover, combined use of alectinib and EGFR-TKIs, including the third-generation inhibitor osimertinib, could overcome resistance in the LMC model. Our findings may provide rationale for clinical trials to investigate the effects of novel therapies dual-targeting ALK and EGFR in ALK-rearranged NSCLC with alectinib-resistant LMC.

Crizotinib-induced osteitis mimicking bone metastasis in a stage IV ALK-rearranged NSCLC patient: a case report

BackgroundTargeted therapies are a standard of care for first-line treatment of Anaplastic lymphoma kinase (ALK)-rearranged non small cell lung cancer (NSCLC). Giving the rapid pace of drug discovery and development in this area, reporting of adverse effects of ALK inhibitors is crucial. Here, we report a case of osteitis induced by an ALK inhibitor mimicking bone metastasis, a previously undescribed side effect of crizotinib.Case presentationA 31-year-old woman with stage IV ALK-rearranged NSCLC presented with back pain after 3 months of crizotinib treatment. Diagnostic work-up showed osteitis on the 4th and 5th thoracic vertebrae, anterior soft tissue infiltration and epiduritis, without any sign of infection. Spinal cord decompression, histological removal and osteosynthesis were performed. Histologic examination showed necrosis with abundant peripheral neutrophils, no microorganism nor malignant cell. Symptoms and Computarized Tomography-abnormalities rapidly diseappeared after crizotinib withdrawal and did not recur after ceritinib onset.ConclusionsThis is the first report of crizotinib-induced osteitis. Crizotinib differs from other ALK inhibitors as it targets other kinases as well, which may have been responsible for the osteitis. Crizotinib can induce rapidly extensive osteitis, which can mimic tumor progression.