UNASSIGNED: Anaplastic lymphoma kinase (ALK) gene-rearrangements are identified in about 3-5% of non-small cell lung cancers (NSCLC), and ALK-rearranged NSCLC is to be considered an oncogene-addicted cancer with peculiar clinical characteristics.
UNASSIGNED: Several ALK inhibitors have been studied and approved for use in the treatment of advanced ALK-rearranged NSCLC with reported superiority in terms of efficacy and safety profile compared with chemotherapy. Second- and third-generation ALK inhibitors (alectinib, brigatinib, and lorlatinib) offer to NSCLC patients a clinically meaningful prolongment of survival with a very good quality of life profile. However, resistances to these agents always occur, with less satisfying options for second-line treatments. Direct comparisons among these agents are not available, and the choice among brigatinib, alectinib, and lorlatinib as first-line treatment remains challenging. Very recently, alectinib has been demonstrated to improve efficacy outcomes compared with chemotherapy also in resected stage IB-IIIA ALK-rearranged NSCLC, extending the clinical benefit offered by ALK inhibitors also to the adjuvant setting.
UNASSIGNED: Future development of ALK inhibitors in NSCLC treatment includes the search for optimal management of acquired resistance to first-line treatments and the extension of use of ALK inhibitors also to neoadjuvant and preferably to perioperative setting.

UNASSIGNED: The use of neoadjuvant anaplastic lymphoma kinase (ALK)-tyrosine kinase inhibitors (TKIs) has not been extensively explored. The current case report highlights the notable pathological complete response (pCR) achieved following neoadjuvant brigatinib therapy in a patient with stage IIIA ALK-positive non-small cell lung cancer (NSCLC).
UNASSIGNED: A 32-year-old male presented with incidental lung lesions, ultimately diagnosed as clinical stage T3N1M0, IIIA NSCLC with an ALK gene rearrangement. Following a multidisciplinary discussion, the patient opted for neoadjuvant brigatinib therapy, which significantly reduced the tumor size. Subsequently, surgery with curative intent was performed, revealing pCR with no residual tumor cells. The patient remained disease-free during a 13-month follow-up period.
UNASSIGNED: This case report provides compelling evidence of pCR following brigatinib therapy in ALK-positive NSCLC, suggesting that surgery after neoadjuvant therapy with brigatinib may offer a safe and effective approach for patients with ALK-positive NSCLC.

OBJECTIVE: There is a lack of real-world data in Asian populations for brigatinib, a next-generation anaplastic lymphoma kinase (ALK) inhibitor for patients with non-small cell lung cancer (NSCLC). This study analysed real-world outcomes and dosing patterns for brigatinib in patients with crizotinib-refractory ALK+ NSCLC in South Korea.
METHODS: This retrospective, non-interventional, cohort study used South Korean Health Insurance and Review Assessment claims data for adults with ALK+ NSCLC who initiated brigatinib between 19 April 2019 and 31 March 2021 after receiving prior crizotinib. Patients\' characteristics, time to discontinuation (TTD), time to dose reduction, overall survival (OS) and treatment adherence were assessed.
RESULTS: The study included 174 patients (56.9% male; 27.0% with a history of brain metastases). Median duration of prior crizotinib was 17 (range 0.3-48) months. Median follow-up after brigatinib initiation was 18 (range 0-34) months. Overall, 88.5% of patients received full-dose brigatinib (180 mg/day) and 93.1% of patients were adherent (proportion of days covered ≥0.8). The median TTD was 24.9 months (95% CI 15.2-not reached). The probability of continuing treatment was 63.2% at 1 year and 51.5% at 2 years. The probability of continuing at full or peak dose was 79.7% at 1 year and 75.6% at 2 years. Median OS was not reached. The 2-year OS rate was 68.7%.
CONCLUSIONS: In this first nationwide retrospective study using national insurance claim data, brigatinib demonstrated real-world clinical benefit as second-line treatment after prior crizotinib in ALK+ NSCLC patients in South Korea.

BACKGROUND: Brigatinib is a next-generation tyrosine kinase inhibitor (TKI) targeting ALK and ROS1. The Barossa study is a multicenter, phase II basket study of brigatinib in patients with ROS1-rearranged solid tumors. ROS1 TKI-naive patients with ROS1-rearranged non-small-cell lung cancer (NSCLC) were enrolled in cohort 1, and ROS1-rearranged NSCLC patients treated previously with crizotinib were enrolled in cohort 2. Patients with ROS1-rearranged solid tumors other than NSCLC were enrolled in cohort 3.
METHODS: Eligible patients received brigatinib at the dose of 180 mg once daily with a 7-day lead-in period at 90 mg. The primary endpoint was the objective response rate (RECIST 1.1) assessed by independent central review in cohorts 1 and 2.
RESULTS: Between July 2019 and June 2021, 51 patients were enrolled into the study. Of the 51, 47 patients had ROS1-rearranged NSCLC; 28 and 19 of these patients were enrolled in cohort 1 and cohort 2, respectively. The remaining four patients had other ROS1-rearranged solid tumors, including rectal, brain, and pancreas tumor in one patient each, and primary unknown tumor in one patient. The confirmed objective response rate was 71.4% [95% confidence interval (CI) 51.3% to 86.8%] in cohort 1 (TKI-naive NSCLC patients) and 31.6% (95% CI 12.6% to 56.6%) in cohort 2 (NSCLC patients treated previously with crizotinib). The median progression-free survival was 12.0 months (95% CI 5.5-22.9 months) in cohort 1 and 7.3 months (95% CI 1.3-17.5 months) in cohort 2. None of the patients in cohort 3 showed any treatment response. Pneumonitis was observed in 9.8% of all the patients.
CONCLUSIONS: Brigatinib was effective in TKI-naive patients with ROS1-rearranged NSCLC. The safety profile of brigatinib was consistent with that reported from previous studies.

We present the case of a 34-year-old Japanese man with anaplastic lymphoma kinase (ALK)-positive non-small cell lung cancer and brain metastases. After central nervous system (CNS) disease progression with alecintib and brigatinib, treatment with lorlatinib resulted in a good intracranial response. In this case, we investigated brain penetration ratio of brigatinib using cerebrospinal fluid and paired serum samples, and the ratio was 0.012. Further, we investigated resistance mechanisms via next-generation sequencing (NGS) using lung biopsy at lung cancer diagnosis and brain biopsy sample at progressive disease of brigatinib. No apparent resistance mechanism of known ALK resistance, such as ALK mutations, amplifications, epithelial-mesenchymal transition (EMT) and bypass pathway activation were detected. Taken together, we speculate that the low CNS penetration rate of brigatinib confers CNS progression. Further studies are warranted to reveal the resistance mechanism and propose a treatment strategy for CNS progression in ALK-positive patients.

Anaplastic lymphoma kinase (ALK) gene rearrangements have been identified as potent oncogenic drivers in several malignancies, including non-small cell lung cancer (NSCLC). The discovery of ALK inhibition using a tyrosine kinase inhibitor (TKI) has dramatically improved the outcomes of patients with ALK-mutated NSCLC. However, the emergence of intrinsic and acquired resistance inevitably occurs with ALK TKI use. This review describes the molecular mechanisms of ALK TKI resistance and discusses management strategies to overcome therapeutic resistance.

The management of non-small cell lung cancer (NSCLC), specifically targeting the anaplastic lymphoma kinase (ALK) with tyrosine kinase inhibitors (TKIs), is challenged by the emergence of therapeutic resistance. Resistance mechanisms to ALK TKIs can be broadly classified into ALK-dependent and ALK-independent pathways. Here, we present a case with lung adenocarcinoma (LUAD) harboring an ALK rearrangement. The patient had developed resistance to sequential ALK TKI therapies, with an acquired ETV6-NTRK3 (E4:N14) fusion as a potential mechanism of ALK-independent resistance to lorlatinib. Subsequently, the patient was treated with the combination of brigatinib plus entrectinib and demonstrated a positive response, achieving an 8-month progression-free survival. Our case provides a potential treatment option for LUAD patients with ALK rearrangements and highlights the utility of next-generation sequencing (NGS) in uncovering genetic alterations that can guide the selection of effective treatment strategies.

In addition to the classical resistance mechanisms, receptor tyrosine-protein kinase AXL is a main mechanism of resistance to third-generation epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) osimertinib in EGFR-mutated non-small cell lung cancer (NSCLC). Developing an effective AXL inhibitor is important to sensitize osimertinib in clinical application. In this study we assessed the efficacy of brigatinib, a second-generation of anaplastic lymphoma kinase (ALK)-TKI, as a novel AXL inhibitor, in overcoming acquired resistance to osimertinib induced by AXL activation. We established an AXL-overexpression NSCLC cell line and conducted high-throughput screening of a small molecule chemical library containing 510 anti-tumor drugs. We found that brigatinib potently inhibited AXL expression, and that brigatinib (0.5 μM) significantly enhanced the anti-tumor efficacy of osimertinib (1 μM) in AXL-mediated osimertinib-resistant NSCLC cell lines in vitro. We demonstrated that brigatinib had a potential ability to bind AXL kinase protein and further inhibit its downstream pathways in NSCLC cell lines. Furthermore, we revealed that brigatinib might decrease AXL expression through increasing K48-linked ubiquitination of AXL and promoting AXL degradation in HCC827OR cells and PC-9OR cells. In AXL-high expression osimertinib-resistant PC-9OR and HCC827OR cells derived xenograft mouse models, administration of osimertinib (10 mg·kg-1·d-1) alone for 3 weeks had no effect, and administration of brigatinib (25 mg·kg-1·d-1) alone caused a minor inhibition on the tumor growth; whereas combination of osimertinib and brigatinib caused marked tumor shrinkages. We concluded that brigatinib may be a promising clinical strategy for enhancing osimertinib efficacy in AXL-mediated osimertinib-resistant NSCLC patients.

The ALTA-1 L trial and EXP-3B arm of NCT01970865 trial found that both brigatinib and lorlatinib showed durable and robust responses in treating ALK-positive non-small cell lung cancer (NSCLC) patients. However, brigatinib and lorlatinib treatments are costly and need indefinite administration until the disease progression. Thus, it remains uncertain whether using brigatinib followed by lorlatinib before chemotherapy is cost-effective compared to reserving these two drugs until progression after chemotherapy.
We used a Markov model to assess clinical outcomes and healthcare costs of treating ALK-positive NSCLC individuals with brigatinib followed by lorlatinib before chemotherapy versus a strategy of reserving these drugs until progression after chemotherapy. Transition probabilities were estimated using parametric survival modeling based on multiple clinical trials. The drug acquisition costs, adverse events costs, administration costs were extracted from published studies before and publicly available data. We calculated lifetime direct healthcare costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios from the perspective of a United States payer.
Our base-case analysis indicated that the incremental cost-effectiveness ratios of using first-line brigatinib followed by lorlatinib compared with second-line brigatinib followed by lorlatinib is $-400,722.09/QALY which meant that second-line brigatinib followed by lorlatinib had less costs and better outcomes. Univariate sensitivity analysis indicated the results were most sensitive to the cost of brigatinib. Probability sensitivity analysis revealed that using brigatinib followed by lorlatinib before chemotherapy had a 0% probability of cost-effectiveness versus delaying these two drugs until progression after chemotherapy at a willingness-to-pay threshold of $150,000 per QALY. Sensitivity analyses conducted revealed the robustness of this result, as incremental cost-effectiveness ratios never exceeded the willingness-to-pay threshold.
Using brigatinib as first-line treatment followed by lorlatinib for ALK-positive NSCLC may not be cost-effective given current pricing from the perspective of a United States payer. Delaying brigatinib followed by lorlatinib until subsequent lines of treatment may be a reasonable strategy that could limit healthcare costs without affecting clinical outcomes. More mature data are needed to better estimate cost-effectiveness in this setting.

The third-generation EGFR-TKI osimertinib is widely used in EGFR-mutated positive non-small cell lung cancer (NSCLC) patients, but drug resistance is inevitable. The currently known mechanisms only explain resistance in a small proportion of patients. For most patients, the mechanism of osimertinib resistance is still unclear, especially for EGFR-independent resistance. Herein, we thoroughly investigated the novel mechanism of osimertinib resistance and treatment strategies. We identified that ST3GAL4, a sialyltransferase, catalyzes terminal glycan sialylation of receptor protein tyrosine kinases, which induces acquired resistance to osimertinib in vitro and in vivo. In addition, ST3GAL4 is generally overexpressed in osimertinib-resistant patients with unknown resistance mechanisms. ST3GAL4 modifies MET glycosylation on N785 with sialylation, which antagonizes K48-related ubiquitin-dependent MET degradation and subsequently activates MET and its downstream proliferation signaling pathways. Meanwhile, ST3GAL4 knockdown or inhibition by brigatinib resensitizes resistant non-small cell lung cancer cells to osimertinib in vitro and in vivo This study suggests that ST3GAL4 can induce acquired resistance to osimertinib, which may be an important EGFR-independent resistance mechanism Furthermore, targeting ST3GAL4 with brigatinib provides new strategies to overcome osimertinib resistance.