[Therapeutic strategies in advanced ALK positive non-small cell lung cancer]

Treatment of advanced ALK-rearranged NSCLC following second-generation ALK-TKI failure

INTRODUCTION

Anaplastic lymphoma kinase (ALK) gene rearrangement is detected in approximately 3-5% of non-small cell lung cancer (NSCLC) cases. Tyrosine kinase inhibitors (TKIs) targeting ALK rearrangement (ALK-TKIs) have shown significant efficacy and improved the survival of patients with NSCLC exhibiting ALK rearrangement. However, almost all patients exhibit disease progression during TKI therapy owing to resistance acquired through various molecular mechanisms, including both ALK-dependent and ALK-independent.

AREAS COVERED

Here, we review the mechanisms underlying resistance to second-generation ALK-TKIs, and the clinical management strategies following resistance in patients with ALK rearrangement-positive NSCLC.

EXPERT OPINION

Treatment strategies following the failure of second-generation ALK-TKIs failure should be based on resistant mechanisms. For patients with ALK mutations who exhibit resistance to second-generation ALK-TKIs, lorlatinib is the primary treatment option. However, the identification of resistance profiles of second-generation ALK-TKIs can aid in the selection of an appropriate treatment strategy. In cases of ALK-dependent resistance mutations, lorlatinib could be the first choice as it exhibits the broadest coverage of mutations that lead to resistance against second-generation ALK-TKIs, such as G1202R, and L1196M. In cases of no resistance mutations, atezolizumab, bevacizumab, and platinum-based chemotherapy could be the alternative treatment options.

Detecting Resistance to Therapeutic ALK Inhibitors in Tumor Tissue and Liquid Biopsy Markers: An Update to a Clinical Routine Practice

The survival of most patients with advanced stage non-small cell lung cancer is prolonged by several months when they are treated with first- and next-generation inhibitors targeting ALK rearrangements, but resistance inevitably emerges. Some of the mechanisms of resistance are sensitive to novel ALK inhibitors but after an initial tumor response, more or less long-term resistance sets in. Therefore, to adapt treatment it is necessary to repeat biological sampling over time to look for different mechanisms of resistance. To this aim it is essential to obtain liquid and/or tissue biopsies to detect therapeutic targets, in particular for the analysis of different genomic alterations. This review discusses the mechanisms of resistance to therapeutics targeting genomic alterations in ALK as well as the advantages and the limitations of liquid biopsies for their identification.