Iruplinalkib (WX-0593) Versus Crizotinib in ALK TKI-Naive Locally Advanced or Metastatic ALK-Positive NSCLC: Interim Analysis of a Randomized, Open-Label, Phase 3 Study (INSPIRE)

Abstract

Introduction: Iruplinalkib (WX-0593) is a new-generation, potent ALK tyrosine kinase inhibitor (TKI) that has been found to have systemic and central nervous system (CNS) efficacy in ALK-positive NSCLC. We compared the efficacy and safety of iruplinalkib with crizotinib in patients with ALK TKI-naive, locally advanced or metastatic ALK-positive NSCLC.

Methods: In this open-label, randomized, multicenter, phase 3 study, patients with ALK-positive NSCLC were randomly assigned to receive iruplinalkib 180 mg once daily (7-d run-in at 60 mg once daily) or crizotinib 250 mg twice daily. The primary end point was progression-free survival (PFS) assessed by Independent Review Committee (IRC) per Response Evaluation Criteria in Solid Tumors version 1.1. Secondary end points included PFS by investigator, objective response rate (ORR), time to response, duration of response, intracranial ORR and time to CNS progression by IRC and investigator, overall survival, and safety. An interim analysis was planned after approximately 70% (134 events) of all 192 expected PFS events assessed by IRC were observed. Efficacy was analyzed in the intention-to-treat population. Safety was assessed in the safety population, which included all randomized patients who received at least one dose of the study drugs. This study is registered with Center for Drug Evaluation of China National Medical Products Administration (CTR20191231) and Clinicaltrials.gov (NCT04632758).

Results: From September 4, 2019, to December 2, 2020, a total of 292 patients were randomized and treated; 143 with iruplinalkib and 149 with crizotinib. At this interim analysis (145 events), the median follow-up time was 26.7 months (range: 3.7-37.7) in the iruplinalkib group and 25.9 months (range: 0.5-35.9) in the crizotinib group. The PFS assessed by IRC was significantly longer among patients in the iruplinalkib group (median PFS, 27.7 mo [95% confidence interval (CI): 26.3-not estimable] versus 14.6 mo [95% CI: 11.1-16.5] in the crizotinib group; hazard ratio, 0.34 [98.02% CI: 0.23-0.52], p < 0.0001). The ORR assessed by IRC was 93.0% (95% CI: 87.5-96.6) in the iruplinalkib group and 89.3% (95% CI: 83.1-93.7) in the crizotinib group. The intracranial ORR was 90.9% (10 of 11, 95% CI: 58.7-99.8) in the iruplinalkib group and 60.0% (nine of 15, 95% CI: 32.3-83.7) in the crizotinib group for patients with measurable baseline CNS metastases. Incidence of grade 3 or 4 treatment-related adverse events was 51.7% in the iruplinalkib group and 49.7% in the crizotinib group.

Conclusions: Iruplinalkib was found to have significantly improved PFS and improved intracranial antitumor activity versus crizotinib. Iruplinalkib may be a new treatment option for patients with advanced ALK-positive and ALK TKI-naive NSCLC.

Funding: This study was funded by Qilu Pharmaceutical Co., Ltd., Jinan, People's Republic of China, and partly supported by the National Science and Technology Major Project for Key New Drug Development (2017ZX09304015).

Keywords: Anaplastic lymphoma kinase; Iruplinalkib; Non–small cell lung cancer; Tyrosine kinase inhibitor.