A phase I, dose-escalation and expansion study of TQ-B3139, a novel ALK TKI, in Chinese ALK or ROS1 positive advanced non-small cell lung cancer (NSCLC).

Abstract

9585 Background: TQ-B3139 is a novel ALK inhibitor with activity 3-7 folds higher than Crizotinib against a broad range of ALK mutations. This phase I study (NCT03099330) is to investigate the safety, and determine the recommended phase II dose (RP2D), and pharmacokinetic (PK), clinical efficacy of TQ-B3139 in Chinese NSCLC patients. Methods: Patients with advanced NSCLC and failed at least one systemic anti-cancer treatment were enrolled. TQ-B3139 was administered orally from 50mg~100mg qd and 200, 300, 400, 500, 600 and 800mg bid, using a PK-guided modified Fibonacci 3+3 dose escalation design. The dose-escalation evaluated patients in 28-day cycles, dose limited toxicities (DLTs) was observed at first cycle. Dose-expansion phase started at dose level which objective response occurs. Treatment was continued until disease progression, death or unacceptable toxicity. Results: Between July 2017 and May 2019, totally 63 patients (59 ALK+, 4 ROS1+) were enrolled. Sixteen patients had prior ALK inhibitor therapy (11 Crizotinib, 5 Ensartinib), and 23 (36.5%) with baseline brain metastasis. Totally, 62 (98.4%) patients experienced treatment-related adverse events (TRAEs), grade 3-4 TRAEs were observed in 21 (33.3%) patients. One DLT occurred in the 800mg bid dose cohort (grade 3 nausea and vomiting). Top 3 common TRAEs were nausea (all grade 87.3%; grade 3-4 3.2%), diarrhea (84.1%, 6.4%), transaminase elevation (65.1%, 4.8%). AUC and Ctrough at steady state increased proportionally from 200mg to 600mg bid. Absorption saturation was observed in 800mg bid. Base on the safety and PK results, PR2D was decided at 600mg bid. Overall ORR was 73.0% (2 CR, 44 PR); DCR was 85.7% (8 SD). Objective response was observed from dose level 200mg bid cohort, ORR and DCR at ≥200mg bid was 78.0% and 89.8%. For ALK TKI-naïve and -resistant patients, the ORR was 78.7% (37/47) and 56.3% (9/16) respectively. For patients with measurable baseline brain metastasis, the ORR for brain lesions was 80.0% (8/10). At data cut-off (23 Jan 2020), 32 events (50.8%) occurred, the median PFS for all patients was 12.1 months (95%CI 8.5-15.6), for patients at ≥200mg bid dose was 12.2 months. The median PFS was not reached for -naive patients (6 months PFS rate 74.5%, 95%CI 68.1-80.9), and 5.6months (95%CI 1.6-9.5) for ALK TKI-resistant patients. Conclusions: TQ-B3139 was well tolerated in Chinese NSCLC patients with high antitumor activity. RP2D was established at 600mg bid. A randomized phase III trial of TQ-B3139 versus Crizotinib in advanced ALK-TKI naïve NSCLC patients is underway. Clinical trial information: NCT03099330 .