Safety and efficacy of WX-0593 in ALK-positive or ROS1-positive non-small cell lung cancer

Abstract

Background: WX-0593 is a potent ALK inhibitor against ALK and ROS1 rearrangement and a series of crizotinib (CRZ)-resistant mutants. We explored the safety and efficacy of WX-0593 in patients (pts) diagnosed with ALK+ or ROS-1+ malignancies, including non-small cell lung cancer (NSCLC). Methods: In this ongoing phase I, dose-escalation, multicenter trial (NCT03389815), 54 pts (third-grade class-A hospital confirmed ALK+ or ROS-1+) received WX-0593 (30, 60, 90, 120, 180, 240 or 300 mg) orally once daily until disease progression or unacceptable toxicity. Activity and safety were evaluated. Results: From 25 September 2017 to 26 December 2018, 54 pts were enrolled, including 46 with ALK+ NSCLC, 10 with ROS1+ NSCLC (2 with both ALK+ and ROS1+, 38.9% with prior CRZ, 9.3% with prior CRZ and second generation ALK inhibitors). Grade 3 QTc prolongation reported in 300 mg cohort was identified as dose-limiting toxicity (DLT). Treatment-emergent adverse events (TAEs) associated with WX-0593 in > 20% of pts include: hypercholesterolemia (40.7%), nausea (40.7%), hypertension (37.0%) increased ALT (31.5%), increased AST (29.6%), hypertriglyceridemia (25.9%), hyperlipidemia (25.9%), vomiting 25.9%. Serious adverse events (SAE) occurred in 6 pts (11.1%). No treatment related death occurred. 2 pts (3.7%) had SAE related with WX-0593 treatment, including increased ALT (dose of 180 mg), increased AST (dose of 180 mg) and chronic heart failure (dose of 300 mg). For ALK+ NSCLC (n=46), objective response rate (ORR) was 29/44 (65.9%). The ORR in CRZ-naive pts was 17/21 (81.0%), 8/18 (44.4%) in CRZ pre-treated pts. ORR was 3/10 (30.0%) in ROS1+ NSCLC pts. By 26 December 2018, median progression-free survival was not reached, 39 patients remained on WX0593 treatment. [Table presented] Conclusions: This study revealed the antitumor activity of WX-0593 in ALK- or ROS-positive NSCLC. Safety profile was acceptable. A phase II trial to evaluate the ORR of 120 mg and 180 mg once daily is ongoing. Clinical trial identification: NCT03389815. Legal entity responsible for the study: Qilu Pharmaceutical Co., Ltd. Funding: Qilu Pharmaceutical Co., Ltd. Disclosure: All authors have declared no conflicts of interest.