Safety, efficacy and biomarker analysis of deulorlatinib (TGRX-326) in ALK-positive non-small-cell lung cancer: a multicentre, open-label, phase 1/1b trial

Introduction: Patients with ALK-positive NSCLC developing resistance to second-generation inhibitors have limited treatment options. Deulorlatinib is a highly brain-penetrant, new-generation ALK/ROS1 inhibitor. We evaluated the safety, efficacy and pharmacokinetics of deulorlatinib in ALK-positive NSCLC.

Methods: This 3-part (dose-escalation/dose-expansion/cohort-expansion), open-label, phase 1/1b trial was conducted at 22 sites in China (ClinicalTrials.gov, NCT05441956). Eligible patients had advanced ALK/ROS1-positive NSCLC. Patients enrolled into dose-escalation/dose-expansion parts were previously treated with ≥1 second-generation ALK inhibitors (ALK-positive) or crizotinib (ROS1-positive); received deulorlatinib 5-125mg once daily. Patients enrolled into cohort-expansion parts were either crizotinib-treated, second-generation TKI-treated or TKI-naïve; received deulorlatinib at recommended phase 2 dose (RP2D). Primary outcomes were safety and tolerability. Here, we report safety analysis in all patients and efficacy analysis in ALK-positive patients.

Results: Between April 2021 and March 2023, 198 patients were enrolled (ALK-positive=171, ROS1-positive=27). Most common treatment-related adverse events (TRAEs) were hypercholesterolemia (79.3%), hypertriglyceridemia (77.3%) and weight gain (53.0%). 40.4% of patients had grade≥3 TRAEs. TRAE-associated dose interruptions, reduction and discontinuation occurred in 11.1%, 3.0% and 1.5% of patients, respectively. The RP2D was set at 60mg once daily. A total of 144 ALK-positive patients were treated at RP2D. For crizotinib-treated (n=14), second-generation TKI-treated (n=97) and TKI-naïve (n=33) patients, ORR to deulorlatinib at RP2D was 71.4%, 38.1%, and 87.9%, respectively. Intracranial ORR was 50%, 70.4%, and 75%. Median duration of response was 18.0 months for second-generation TKI-treated patients, and not reached for crizotinib-treated and TKI-naïve patients. Biomarker analyses identified undetectable ALK alterations at baseline and ALK ctDNA clearance at week 6 as potential predictive biomarkers.

Conclusions: Deulorlatinib showed desirable tolerability and efficacy in ALK-positive NSCLC, demonstrating the potential to become a new treatment option in this population.