Efficacy and safety of lorlatinib in Asian and non-Asian patients with ALK-positive advanced non-small cell lung cancer: Subgroup analysis of a global phase 2 trial

Abstract

Objectives: To analyze the efficacy and safety of lorlatinib in Asian and non-Asian patients with pretreated anaplastic lymphoma kinase (ALK)-positive, advanced non-small cell lung cancer (NSCLC) from a phase 1/2 study.

Materials and methods: In this ongoing phase 2 part of the trial, patients with ALK- or ROS1-positive, advanced NSCLC enrolled into six expansion cohorts (EXP1-6), based on ALK and ROS1 status and previous therapy, and received lorlatinib 100 mg once daily. The primary endpoint was objective tumor response and intracranial response. Post hoc analyses of activity were conducted in Asian and non-Asian (based on race) ALK-positive patients who received either previous crizotinib with or without chemotherapy (EXP2-3A) or at least one second-generation ALK tyrosine kinase inhibitor with any number of chemotherapy regimens (EXP3B-5). Analysis of safety (adverse events [AEs]) was in the phase 1 and 2 study population who started lorlatinib 100 mg once daily.

Results: 17 Asian patients were enrolled in EXP2-3A and 53 in EXP3B-5; 33 non-Asian patients were enrolled in EXP2-3A and 73 in EXP3B-5. Objective response rates in the Asian and non-Asian subgroups were 82.4% (95% confidence interval [CI]: 56.6-96.2) and 63.6% (95% CI: 45.1-79.6) in EXP2-3A, and 47.2% (95% CI: 33.3-61.4) and 30.1% (95% CI: 19.9-42.0) in EXP3B-5, and median progression-free survival was 13.6 and 12.5 months (EXP2-3A) and 6.9 and 5.5 months (EXP3B-5). Lorlatinib exhibited antitumor activity across ALK resistance mutations, while no differences according to the EML4-ALK variant could be detected. The most common treatment-related AEs were hypercholesterolemia, hypertriglyceridemia, edema, and peripheral neuropathy in both Asian and non-Asian subgroups.

Conclusion: Lorlatinib showed substantial overall and intracranial activity in pretreated patients with ALK-positive NSCLC in both Asian and non-Asian patients. AE profiles were similar between Asian and non-Asian patients.

Clinicaltrials: gov NCT01970865.

Keywords: Anaplastic lymphoma kinase; Asian; Lorlatinib; Non-small cell lung cancer; Tyrosine kinase inhibitor.