EML4-ALK G1269A

In this study, we systematically explored the validity of sequential ALK inhibitors (alectinib, lorlatinib, crizotinib, ceritinib and brigatinib) for a heavy-treated patient with EML4-ALK fusion via developing an in vitro and in vivo drug testing system based on patient-derived models. In summary, our results delineate clinical responses of sequential ALK-TKIs treatments and provide insights into the mechanisms underlying the superior effects of brigatinib in patients harboring ALKG1269A mutation and resistant towards alectinib, lorlatinib and crizotinib. The molecular signatures model based on the combination of IL6, CXCL1 and CXCL5 has the potential to predict prognosis of EML4-ALK positive NSCLC patients.

The model is a non-small cell lung cancer harboring EML4-ALK fusion and ALK C1156Y/G1269A mutation, sensitive to the 3rd generation ALK TKI lorlatinib... We demonstrated potential targetable features of DTP cells. A combination of targeted therapies with DTP drug candidates could represent a therapeutic opportunity to improve the depth of response and delay the emergence of resistance in patients.

This study demonstrated that the combination of p53 protein agonist and lorlatinib may provide a new therapeutic strategy for NSCLC patients with lorlatinib resistance and TP53 mutation. Furthermore, the results also provide guidance for selecting optimal chemo-regimens for NSCLC patients after ALK-TKIs failure.

Crizotinib, ceritinib, alectinib, brigatinib, and lorlatinib are approved tyrosine kinase inhibitors (TKIs) for ALK-positive NSCLC, but durability of response is partly limited by ALK resistance mutations...Ascites mononuclear cells were isolated by Ficoll centrifugation and cultured in media (DMEM F12 Glutamax, 10% antibiotics/antimycotics, 10% FBS, hydrocortisone, adenine, RockInhibitor, and 1/10 cholera toxin)... NVL-655 has demonstrated activity in many preclinical models bearing ALK compound mutations, including the MR448re (EML4-ALK v3 G1202R/T1151M) model. The potent preclinical activity of NVL-655 suggests potential clinical utility for ALK-positive patients, including those with resistant compound mutations. The MR448re PDC and xenograft are valuable additions to the ALK therapeutic research landscape where there is limited availability of patient-derived models with lorlatinib-resistant ALK compound mutations.

ALK rearrangements are detected in approximately 4% of patients with advanced non-small cell lung cancer (NSCLC), and the tyrosine kinase inhibitors (TKIs) crizotinib, alectinib, brigatinib, ceritinib, and lorlatinib have been approved by the FDA for the treatment of ALK-positive NSCLC. The dPCR method was highly sensitive in detecting gene mutations with low allele frequency. It was also found to be able to monitor variable resistance mutations over time during ALK-TKI treatment. In addition, we found that the appearance of G1202R did not always indicate clinical acquisition of resistance that required drug modification.

Here, we report, for the first time, a novel, sequentially-evolved EML4-ALK variant 3 G1202R/S1206Y double mutation in cis detected in a patient with ALK-positive NSCLC after disease progression on sequential crizotinib, alectinib, and then lorlatinib. Three-dimensional computer modeling of this double mutation and other G1202R-based double mutations with lorlatinib (ALK G1202R/L1196M, ALK G1202R/F1174C, ALK G1202R/l1198F, ALK G1202R/G1269A) were provided to reveal how these double mutations may confer resistance to lorlatinib through diverse steric hindrances in the ALK kinase domain. In addition, we performed a comprehensive literature review on published acquired double or triple ALK mutations that are resistant to lorlatinib from both patient samples and in vitro mutagenesis experiments.

" 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). 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. Research Funding: Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Korean government (MSIT) (No.NRF-2017M3A9G5060259)Bio & Medical Technology Development Program of the National Research Foundation (NRF) funded by the Kor"