Anaplastic Lymphoma Kinase (ALK) Inhibitors Show Activity in Colorectal Cancer With ALK Rearrangements: Case Series and Literature Review

Anaplastic lymphoma kinase (ALK) rearrangement is a well-known driver oncogene detected in approximately 5% of non-small cell lung cancer. However, ALK rearrangement is much less frequent in other solid tumors outside the lungs, such as colorectal cancer (CRC); thus, the optimal management of CRC with ALK rearrangements has yet to be established. In this report, we describe 2 cases of ALK-positive CRC, both of which benefited from ALK tyrosine kinase inhibitor (ALK-TKI) therapy. Case 1 was a postoperative patient with poorly differentiated colon adenocarcinoma, who was diagnosed with metastatic relapse shortly after surgery. Both fluorouracil, leucovorin, and oxaliplatin (FOLFOX) and bevacizumab combined with 5-fluorouracil, l-leucovorin, and irinotecan (FOLFIRI) proved ineffective against the disease. The patient was then treated with ensartinib, as the CAD-ALK fusion gene was detected by genomic analysis. The patient was initially treated with ensartinib monotherapy for 9 months, then with ensartinib combined with local radiotherapy and fruquintinib for another 4 months for isolated hilar hepatic lymph node metastasis. The patient experienced disease progression with an acquired ALK G1202R resistance mutation that responded well to lorlatinib. Case 2 involved a 72-year-old man with advanced colon cancer (pT4bN2aM1b, stage IV) harboring an EML4-ALK fusion. The patient underwent resection of the right colon tumor due to intestinal obstruction, but the disease continued to progress after 12 courses of FOLFIRI and bevacizumab chemotherapy. However, the patient responded remarkably well to alectinib. Our report emphasizes the importance of gene detection in the treatment of malignant tumors, and the significance of ALK mutations in CRC.

Case report: Clinical complete response in advanced ALK-positive lung squamous cell carcinoma: a case study of successful anti-PD-1 immunotherapy post ALK-TKIs failure

In patients with advanced lung adenocarcinoma (LADC) harboring the echinoderm microtubule-associated protein-like 4 (EML4) -anaplastic lymphoma kinase (ALK) rearrangement, targeted therapy typically demonstrates superior efficacy as an initial treatment compared to chemotherapy. Following resistance to ALK-tyrosine kinase inhibitors (TKIs), regimens incorporating platinum-based dual agents or combined with bevacizumab often show effectiveness. However, therapeutic alternatives become constrained after resistance develops to both TKIs and platinum-based therapies. Given that the majority of ALK-positive non-small cell lung carcinomas (NSCLC) are LADC, the benefits of TKIs for patients with ALK-positive lung squamous cell carcinoma (LSCC) and the optimal treatment strategy for these patients remain a subject of debate. In this case study, we report on a patient with advanced LSCC, in whom the EML4-ALK rearrangement was identified via ARMS-PCR (Amplification Refractory Mutation System-Polymerase Chain Reaction). The patient underwent oral treatment with crizotinib and alectinib, showing effectiveness in both first-line and second-line ALK-TKI therapies, albeit with limited progression-free survival (PFS). Subsequent resistance to second-generation TKI was followed by the detection of tumors in the left neck region via computed tomography (CT). Biopsy pathology revealed non-squamous cell carcinoma, and subsequent treatment with platinum-based double-drug therapy proved ineffective. Further analysis through next-generation sequencing (NGS) indicated ALK negativity but a high expression of programmed death-ligand 1 (PD-L1). Immunotherapy was then initiated, resulting in a PFS of over 29 months and clinical complete remission (cCR). This case underscores the potential benefit of ALK-TKIs in patients with ALK-positive LSCC. Resistance to second-generation TKIs may lead to ALK negativity and histological transformation, highlighting the necessity of repeated biopsies post-TKI resistance for informed treatment decision-making. As of November 2023, imaging studies continue to indicate cCR in the patient, with a survival time exceeding 47 months.

Effects of drug-drug interactions and CYP3A4 variants on alectinib metabolism

In this study, the effects of 17 CYP3A4 variants and drug-drug interactions (DDI) with its mechanism on alectinib metabolism were investigated. In vitro incubation systems of rat liver microsomes (RLM), human liver microsomes (HLM) and recombinant human CYP3A4 variants were established. The formers were used to screen potential drugs that inhibited alectinib metabolism and study the underlying mechanism, and the latter was used to determine the dynamic characteristics of CYP3A4 variants. Alectinib and its main metabolite M4 were quantitatively determined by ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). The results showed that compared with CYP3A4.1, only CYP3A4.29 showed higher catalytic activity, while the catalytic activity of CYP3A4.4, .7, .8, .12, .14, .16, .17, .18, .19, .20, .23, and .24 decreased significantly. Among them, the catalytic activity of CYP3A4.20 is the lowest, only 2.63% of that of CYP3A4.1. Based on the RLM incubation system in vitro, 81 drugs that may be combined with alectinib were screened, among which 18 drugs had an inhibition rate higher than 80%. In addition, nicardipine had an inhibition rate of 95.09% with a half-maximum inhibitory concentration (IC50) value of 3.54 ± 0.96 μM in RLM and 1.52 ± 0.038 μM in HLM, respectively. There was a mixture of non-competitive and anti-competitive inhibition of alectinib metabolism in both RLM and HLM. In vivo experiments of Sprague-Dawley (SD) rats, compared with the control group (30 mg/kg alectinib alone), the AUC(0-t), AUC(0-∞), Tmax and Cmax of alectinib administered in combination with 6 mg/kg nicardipine were significantly increased in the experimental group. In conclusion, the metabolism of alectinib was affected by polymorphisms of the CYP3A4 gene and nicardipine. This study provides reference data for clinical individualized administration of alectinib in the future.

Cost-effectiveness of ensartinib, crizotinib, ceritinib, alectinib, brigatinib and lorlatinib in patients with anaplastic lymphoma kinase-positive non-small cell lung cancer in China

Objective

Six anaplastic lymphoma kinase-tyrosine kinase inhibitors (ALK-TKIs), including one domestic (ensartinib) and five imported ALK-TKIs (crizotinib, ceritinib, alectinib, brigatinib, and lorlatinib), have been recommended as first-line treatments for advanced ALK-positive NSCLC in China. This study sought to examine the cost-effectiveness of these six novel therapies in Chinese patients.

Material and methods

We constructed a Markov model to compare the cost-effectiveness of the six ALK-TKIs as a first-line treatment for patients with advanced ALK-positive NSCLC from the perspective of the Chinese healthcare system. Transition probabilities were estimated by synthesizing data from the PROFILE 1,029 trial and a network meta-analysis. Health state utilities and costs were sourced from published literature, publicly available national databases, and local general hospitals. The robustness of model was assessed via deterministic sensitivity analyses and probabilistic sensitivity analyses.

Results

Compared with crizotinib, ensartinib achieved additional 0.12 quality-adjusted life-year (QALY) with marginal costs of $3,249, resulting in an incremental cost-effectiveness ratio (ICER) of $27,553/ QALY. When compared with ceritinib and brigatinib, ensartinib achieved additional 0.06 and 0.03 QALYs with substantially reduced costs. When compared with lorlatinib and alectinib, ensartinib was associated with a lower QALY and decreased total costs; the ICERs for lorlatinib and alectinib were $934,101/ QALY and $164,888/ QALY, respectively.

Conclusion

For Chinese patients with advanced ALK-positive NSCLC, ensartinib was a cost-effective option compared with crizotinib, and was a dominant alternative to ceritinib and brigatinib. Although lorlatinib and alectinib were associated with prolonged survival compared with ensartinib, they were less cost-effective than ensartinib due to the overwhelming total costs.

Identification and therapeutic evaluation of ALK rearrangements in non-small-cell lung cancer

This study aimed to present a comprehensive assessment of anaplastic lymphoma kinase (ALK) rearrangements evaluated by DNA/RNA-based next-generation sequencing (NGS) and Ventana immunohistochemistry (IHC) in patients with non-small-cell lung cancer (NSCLC) and to evaluate the therapeutic outcomes of ALK tyrosine kinase inhibitor (TKI) treatment. We investigated ALK gene fusions in 14,894 patients with NSCLC using Ventana IHC and NGS, including 12,533 cases detected via DNA-based NGS and 2,361 cases using RNA-based NGS. The overall percentage agreement (OPA), positive percentage agreement (PPA), and negative percentage agreement (NPA) were calculated when comparing the results between NGS and IHC. The therapeutic responses to ALK-TKIs were also evaluated. In total, 3.50% (439/12,533) of specimens were NGS ALK-positive (NGS-p) in the DNA-based NGS cohort and 3.63% (455/12,533) were IHC ALK-positive (IHC-p). The OPA of NGS was 99.60%, whereas its PPA and NPA were 92.75 and 99.86%, respectively. In the adenocarcinoma (ADC) subcohort, the PPA was 95.69%. In the RNA-based NGS cohort, 2.20% (52/2,361) of specimens were NGS-p and 2.63% (62/2,361) were IHC-p. The OPA of NGS was 99.49%; its PPA and NPA were 82.26 and 99.96%, respectively. Thirteen patients with discordant results received ALK-TKI treatment. In the seven NGS-p/IHC-negative (IHC-n) patients, the overall response rate (ORR) was 85.4% (6/7) and the disease control rate (DCR) was 100%. In the six NGS-negative/IHC-p patients, the ORR was 66.7% (4/6) and the DCR was 100%. In summary, a high concordance of ALK gene fusion detected via NGS and IHC was observed in this study. DNA-based NGS had a higher OPA, PPA, and PPA in the ADC subcohort, whereas RNA-based NGS had a higher NPA. Overall, the results suggest that the combination of NGS and IHC can improve the accuracy of ALK fusion detection; hence, a result determination algorithm for clinical detection of ALK gene fusion was also proposed.

Real-World Efficacy and Tolerability of Brigatinib in Patients with Non-Small Cell Lung Cancer with Prior ALK-TKIs in the United States

BACKGROUND

Real-world evidence for brigatinib, a next-generation anaplastic lymphoma kinase-tyrosine kinase inhibitor (ALK-TKI) used in ALK-rearranged non-small cell lung cancer, is scarce. This retrospective study evaluated real-world brigatinib utilization in the US post other ALK-TKIs.

MATERIALS AND METHODS

Adults with ≥1 brigatinib claim (index date) between 1 April 2017 and 30 September 2020 in the IQVIA longitudinal pharmacy claims database were followed until dose reduction, discontinuation, or end of follow-up. Patients had ≥12 months pre- and ≥1-month post-index observations.

RESULTS

A total of 413 patients treated with brigatinib were analyzed. Over 80% received ≥1 prior ALK-TKI; alectinib and crizotinib were the most common (58.8% and 51.3% patients, respectively). The median follow-up was 8.4 months. The median time to treatment discontinuation (TTD) for brigatinib was 10.3 months (95% CI, 8.2-15.0), with 45% remaining on therapy at 12 months. The TTD was shortest (~8 months) in patients receiving both crizotinib and alectinib and longest in patients who received alectinib only prior to brigatinib (11.8 months). Adherence was high, with 92.7% of patients having a medication possession ratio of >80%. The mean dose compliance score was 1.0. Most patients reached the brigatinib dose of 180 mg/day (77%); 13.2% of patients had a dose reduction, with 89.3% and 84.6% continuing 180 mg/day therapy at 3 and 6 months, respectively.

CONCLUSIONS

Brigatinib appears to be effective and well-tolerated in the real-world ALK+ NSCLC population in the US, showing benefit in patients after a next-generation ALK-TKI. Notably, dose reduction rates appeared markedly less than those seen in trials when most trial-related dose reductions were for asymptomatic laboratory abnormalities.

Holistic View of ALK TKI Resistance in ALK-Positive Anaplastic Large Cell Lymphoma

Anaplastic lymphoma kinase (ALK) is a receptor tyrosine kinase expressed at early stages of normal development and in various cancers including ALK-positive anaplastic large cell lymphoma (ALK+ ALCL), in which it is the main therapeutic target. ALK tyrosine kinase inhibitors (ALK TKIs) have greatly improved the prognosis of ALK+ALCL patients, but the emergence of drug resistance is inevitable and limits the applicability of these drugs. Although various mechanisms of resistance have been elucidated, the problem persists and there have been relatively few relevant clinical studies. This review describes research progress on ALK+ ALCL including the application and development of new therapies, especially in relation to drug resistance. We also propose potential treatment strategies based on current knowledge to inform the design of future clinical trials.

Effects of food on the pharmacokinetics of ensartinib in healthy Chinese subjects

Ensartinib is a promising, aminopyridazine-based small molecule that potently inhibits anaplastic lymphoma kinase. This random, two-period, crossover study evaluated the effects of food on the pharmacokinetics of ensartinib after a single dose (225 mg) in healthy Chinese subjects. The pharmacokinetic parameters of ensartinib were calculated using non-compartmental analysis. Twenty-four Chinese healthy subjects aged 20-44 years were included in this study. The area under the concentration-time curve of ensartinib was approximately 25% lower after the intake of a high-fat, high-calorie meal prior to dosing, whereas the maximum plasma concentration was decreased by approximately 37%, illustrating the statistically significant effect of food on ensartinib pharmacokinetics. In addition, food intake prolonged the absorption phase of ensartinib (median time to maximum plasma concentration, from 4.5 to 6 h). Population pharmacokinetic (PopPK) analysis was conducted using NONMEM, and the influences of food, age, sex, body weight, and body mass index were studied via covariate analysis. In this analysis, ensartinib plasma concentrations were best described by a one-compartment model with Weibull absorption. The final model included food and age as covariates on apparent distribution and apparent clearance. Based on the final PopPK model, food was identified as a significant covariate for apparent clearance, apparent volume of distribution, and absorption rate constant, consistent with the results of non-compartmental pharmacokinetic analysis.

The mechanisms of resistance to second- and third-generation ALK inhibitors and strategies to overcome such resistance

INTRODUCTION

Anaplastic lymphoma kinase (ALK) inhibitors are widely known to contribute to the long-term survival of ALK-rearranged non-small cell lung cancer (NSCLC) patients. Based on clinical trial data, treatment with second- or third-generation ALK inhibitors can be initiated after crizotinib therapy without analyzing resistance mechanisms, and some randomized trials have recently shown the superiority of second- or third-generation ALK inhibitors over crizotinib as the initial treatment; however, the optimal treatment for patients who relapse while on second- or third-generation ALK inhibitors is not well-defined.

AREAS COVERED

This review provides an overview of the mechanisms of resistance to second- or third-generation ALK inhibitors that have been identified in both clinical and pre-clinical settings, and introduces strategies for overcoming resistance and discusses ongoing clinical trials.

EXPERT OPINION

The comprehensive elucidation of both ALK-dependent and ALK-independent resistance mechanisms is necessary to improve the prognosis of patients with ALK-rearranged NSCLC. Liquid biopsy to clarify these mechanisms of resistance might play an important role in the near future.

NGS-based liquid biopsy profiling identifies mechanisms of resistance to ALK inhibitors: a step toward personalized NSCLC treatment

Despite impressive and durable responses, nonsmall cell lung cancer (NSCLC) patients treated with anaplastic lymphoma kinase (ALK) inhibitors (ALK-Is) ultimately progress due to development of resistance. Here, we have evaluated the clinical utility of circulating tumor DNA (ctDNA) profiling by next-generation sequencing (NGS) upon disease progression. We collected 26 plasma and two cerebrospinal fluid samples from 24 advanced ALK-positive NSCLC patients at disease progression to an ALK-I. These samples were analyzed by NGS and digital PCR. A tool to retrieve variants at the ALK locus was developed (VALK tool). We identified at least one resistance mutation in the ALK locus in ten (38.5%) plasma samples; the G1269A and G1202R mutations were the most prevalent among patients progressing to first- and second-generation ALK-Is, respectively. Overall, 61 somatic mutations were detected in 14 genes: TP53, ALK, PIK3CA, SMAD4, MAP2K1 (MEK1), FGFR2, FGFR3, BRAF, EGFR, IDH2, MYC, MET, CCND3, and CCND1. Specifically, a deletion in exon 19 in EGFR, a non-V600 BRAF mutation (G466V), and the F129L mutation in MAP2K1 were identified in four patients who showed no objective survival benefit from ALK-Is. Potential ALK-I-resistance mutations were also found in PIK3CA and IDH2. Finally, a c-MYC gain, along with a loss of CCND1 and FGFR3, was detected in a patient progressing on a first-line treatment with crizotinib. We conclude that NGS analysis of liquid biopsies upon disease progression identified different putative ALK-I-resistance mutations in most cases and could be a valuable approach for therapy decision making.

Novel MRPS9-ALK Fusion Mutation in a Lung Adenocarcinoma Patient: A Case Report

Anaplastic lymphoma kinase (ALK) rearrangements account for approximately 5-6% of non-small-cell lung cancer (NSCLC) patients. In this study, a case of lung adenocarcinoma harboring a novel MRPS9-ALK fusion is reported. The patient responded well to the first and second generation of ALK-tyrosine kinase inhibitors (ALK-TKIs) (crizotinib then alectinib), as her imaging findings and clinical symptoms significantly improved. At last follow-up, over 21 months of overall survival (OS) has been achieved since ALK-TKI treatment. The progression-free survival (PFS) is already ten months since alectinib. The adverse effects were manageable. The case presented here provides first clinical evidence of the efficacy of ALK-TKIs in NSCLC patients with MRPS9-ALK fusion.

Phase II, Open-label, Single-arm, Multicenter Study to Assess the Activity and Safety of Alectinib as Neoadjuvant Treatment in Surgically Resectable Stage III ALK-positive NSCLC: ALNEO Trial

BACKGROUND

Alectinib is a potent anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitor (TKI) which is currently used in the first-line setting of advanced ALK⁺ non-small cell lung cancer (NSCLC). Despite favorable results in the metastatic setting, the activity of alectinib in locally-advanced ALK+ NSCLC as a neoadjuvant treatment remains to be assessed. We report the case of a patient with stage IIIA ALK⁺ NSCLC (cT2aN2) who received alectinib as neoadjuvant treatment, achieving major pathological response (MPR) at pathologic examination. Hence we present the treatment rationale and study design of a phase II, open-label, single-arm, multicenter clinical trial (ALNEO study, EUDRACT number 2020-003432-25).

MATERIALS AND METHODS

Patients with potentially resectable stage III ALK⁺ NSCLC (any T with N2, T4N0-1) will be registered to receive oral alectinib 600 mg twice daily for 2 cycles of 4 weeks each (8 weeks totally) during the neoadjuvant phase. After definitive surgery, patients will enter in the adjuvant setting, during which they will receive alectinib 600 mg twice daily for 24 cycles (96 weeks). The primary endpoint is MPR, defined as ≤10% residual viable tumor cells histologically detected in the resected primary tumor and all resected lymph nodes after surgery. Secondary endpoints include pathological complete response, objective response, event-free survival, disease-free survival, overall survival, adverse events.

CONCLUSIONS

Our case report supports the feasibility of alectinib as neoadjuvant treatment. ALNEO study will further explore the activity and safety of this novel treatment strategy.

Adverse Events of Concurrent Radiotherapy and ALK Inhibitors for Brain Metastases of ALK-Rearranged Lung Adenocarcinoma

BACKGROUND

We investigated acute adverse events in patients with brain metastases (BMs) of anaplastic lymphoma kinase-rearranged (ALKr) non-small cell lung cancer (NSCLC) treated with both cranial radiotherapy and tyrosine kinase inhibitors (TKIs) of ALK.

PATIENTS AND METHODS

Acute AEs were retrospectively investigated in patients with BMs of ALKr-NSCLC who received both whole-brain radiotherapy (WBRT) and ALK-TKI. For comparison, they were also assessed in patients with epidermal growth factor receptor (EGFR)-mutated NSCLC and wild-type with neither ALK rearrangement nor EGFR mutation treated with WBRT.

RESULTS

Two ALKr cases were consequently eligible. Grade 3 otitis media unexpectedly occurred in both cases, while there was one case out of 11 and one case out of 18 of grade 2 otitis media among the EGFR-mutated cases and wild-type cases (p=0.013), respectively.

CONCLUSION

Concurrent treatment with WBRT and ALK-TKI may be associated with acute severe ear toxicity in patients with BMs of ALKr-NSCLC.

First-line treatment of advanced non-small cell lung cancer with ALK rearrangement: state of the art and future development

INTRODUCTION

Approximately 5% of all diagnosed non-small cell lung cancer (NSCLC) patients harbor a genetic rearrangement between the ALK and EML4 genes, representing a specific molecular, histological and clinical subgroup (ALK+ NSCLC). To date, upfront treatment with ALK-tyrosine-kinase inhibitors (ALK-TKIs) has replaced chemotherapy in the first line setting for this subset of patients with excellent results. However, all treated patients eventually develop acquired resistance mechanisms to these agents (mainly resistance mutations) and experience progression of the disease. Areas covered: This paper provides a comprehensive state-of-the-art review about first-line approved ALK-TKIs, furthermore, it discusses the most promising ALK-TKIs under development designed to overcome resistance mutations and their implications. Expert opinion: Alectinib should currently be regarded as the standard of care for the first-line treatment of ALK+ NSCLC, considering its superior efficacy and safety profile. Regarding developing agents, lorlatinib and ensartinib appear to be the most promising ones, even though the data from their trials are still immature.

[Current Status for Anaplastic Lymphoma Kinase in Non-small Cell Lung Cancer]

The incidence of ALK gene rearrangement in non-small cell lung cancer (NSCLC) was about 3% to 5%. ALK gene inhibitors have made great breakthrough in recent years, significantly extending the survival period of patients with ALK(+) advanced NSCLC. But the majority of patients will be acquired drug resistance after treatment. This article has been explained separately from the ALK genetic background, the detection method, the treatment of the three generations of ALK inhibitors and the strategy after drug resistance. It is desire to have reference value and reference meaning for clinical work.
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A successful pembrolizumab treatment case of lung adenocarcinoma after becoming resistant to ALK-TKI treatment due to G1202R mutation

BACKGROUND

In current guidelines, the role of immune checkpoint inhibitors is not yet determined in the treatment strategy for NSCLC harboring ALK translocations.

CASE

A 51-year-old woman with lung adenocarcinoma harboring ALK translocation was treated with alectinib until PD. After the second (CDDP/PEM) and third (crizotinib) line treatment, a second biopsy was performed, revealing PD-L1 tumor proportion score of 70-80% and G1202R mutation of ALK. Pembrolizumab was selected for the fourth line, leading to PR for more than 6 months.

CONCLUSIONS

While alectinib might induce resistance to ALK-TKI, it could increase PD-L1 positive cells to become sensitive to PD-1/PD-L1 inhibitors.

Optimal management of ALK-positive NSCLC progressing on crizotinib

Crizotinib is an anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitor (-TKI) that represents the standard first-line treatment of patients with ALK-rearranged (ALK-positive) advanced non-small cell lung cancer (NSCLC). In this setting, crizotinib has demonstrated a response rate of roughly 75% and a median progression-free survival just under one year. However, acquired resistance will emerge in virtually all crizotinib-treated patients, whose management may require a diversified approach according to the pace of the disease and/or the site(s) of disease progression. Crizotinib beyond disease progression is an option in patients with oligoprogressive disease, especially in presence of isolated central nervous system (CNS) relapse, provided that local ablative therapy (mainly radiotherapy) to the brain is administered. On the other hand, novel more potent and highly selective ALK-TKIs with demonstrated anti-tumor activity (CNS included) in crizotinib-refractory patients have been made available in recent years. Therefore, clinicians may well consider switching to a second-generation ALK-TKI as treatment option in case of progression on crizotinib. Therapeutic chances are more limited for patients who progress after crizotinib and a second-generation ALK-TKI, for whom both a third-generation ALK-TKI or pemetrexed-based chemotherapy could prove beneficial, while evidence in support of the use of immunotherapy in patients pretreated with ≥1 ALK-TKI is lacking.

Progression-Free and Overall Survival of Patients With ALK Rearrangement-Positive Non-Small Cell Lung Cancer Treated Sequentially With Crizotinib and Alectinib

INTRODUCTION

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) show marked therapeutic efficacy in patients with non-small cell lung cancer (NSCLC) harboring the echinoderm microtubule-associated protein-like 4-ALK fusion gene. The effect on overall survival (OS) of sequential treatment with the first- and second-generation ALK-TKIs crizotinib and alectinib, respectively, has remained unknown. We have examined the clinical outcome of such sequential treatment in a retrospective analysis of patients with ALK-rearranged NSCLC.

MATERIALS AND METHODS

Eleven patients with ALK-rearranged NSCLC treated with crizotinib followed by alectinib were identified. The progression-free survival (PFS) and OS for these patients were determined from a retrospective review of their medical records.

RESULTS

The median PFS on crizotinib or alectinib was 6.1 months (range, 1.0-15.4 months) and 15.2 months (range, 1.0-28.3 months), respectively. The median combined PFS for both crizotinib and alectinib was 18.2 months (range, 10.4-43.7 months). Crizotinib was continued beyond radiographic evidence of progressive disease in 6 of the 11 patients, with a median duration of postprogression crizotinib treatment of 9.4 months (range, 0-20.5 months). The OS period from the diagnosis of metastatic disease or the initiation of crizotinib treatment was 51.1 months (range, 20.9-69.5 months) and 48.6 months (range, 19.8-50.1 months), respectively.

CONCLUSION

Our retrospective study has revealed durable survival for alectinib treatment after crizotinib failure in patients with ALK-rearranged NSCLC.

Future options for ALK-positive non-small cell lung cancer

Recent advances in the understanding of non-small cell lung cancer (NSCLC) biology have revealed a number of 'targetable' genetic alterations that underlie cancer growth and survival in specific patients subgroups. The anaplastic lymphoma kinase (ALK) gene rearrangement identifies a population of NSCLCs in whom dysregulation of ALK-tyrosine kinase (-TK) leads to uncontrolled proliferation of cancer cells, thus providing the basis for the therapeutic use of ALK-TK inhibitors (-TKIs) in ALK-rearranged (-positive) disease. Crizotinib was the first ALK-TKI to undergo clinical development in ALK-positive advanced NSCLC, in which it has been shown to greatly outperform the best available chemotherapy regimen in either second- or first-line setting. More recently, the novel second-generation ALK-TKI ceritinib has been shown to be highly active in either crizotinib-pretreated or -naïve population. Nevertheless, as mechanisms of resistance to crizotinib and ALK-TKIs in general are being progressively elucidated, the treatment landscape of ALK-positive NSCLC is expected to evolve rapidly. In the present review we will briefly discuss the current knowledge of ALK-positive advanced non-small cell lung cancer. Also, we will touch upon new developments on drugs/combination regimens aimed at inhibiting the ALK-TK, in an attempt to delineate how treatment of ALK-positive disease may change in the next future.