Brigatinib In Japanese Alk Positive Nsclc Patients Previously Treated With Alk Tyrosine Kinase Inhibitors: J-Alta.

9537 Background: Brigatinib is an ALK inhibitor with demonstrated activity against ALK resistance mutations. To evaluate efficacy and safety in Japanese patients with ALK-positive non-small cell lung cancer (NSCLC), a prospective, single-arm, phase 2 study was conducted. We report the efficacy and safety of brigatinib in patients who have progressed on alectinib with or without prior crizotinib and of those who previously received up to two ALK tyrosine kinase inhibitors (TKIs) with or without prior chemotherapy. Methods: A safety evaluation lead-in was followed by an expansion stage of an ALK TKI-naïve and two ALK TKI-refractory cohorts. The refractory cohorts included patients with stage IIIB, IIIC, or IV NSCLC with ALK rearrangements. This report describes efficacy results from the post-alectinib patients in the expansion cohort and safety results from all refractory patients. The primary endpoint was confirmed objective response rate (ORR) assessed by IRC, secondary endpoints included duration of response (DoR), progression-free survival (PFS), disease control rate (DCR), and intracranial ORR (iORR). Brigatinib was administered at 180 mg QD with 90 mg QD lead-in for the first 7 days, and efficacy was evaluated every 8 weeks. Results: A total of 72 patients were enrolled in 28 sites, including a cohort of 47 patients with prior alectinib, with/without crizotinib between January 2018 and September 2019. The primary analysis of brigatinib in this cohort (data cut-off date 26 September 2019) demonstrated an IRC-assessed, confirmed ORR of 30% and a median DoR of 6.1 months. The median PFS was 7.3 months. Clinically meaningful intracranial efficacy was also observed (see table). Grade ≥3 TEAEs included blood creatine phosphokinase increase (18.1%), lipase increase (13.9%), hypertension (11.1%), amylase increase (4.2%), and pneumonitis (1.4%). Brigatinib also showed anti-tumor activity in patients with refractory secondary mutations in the ALK kinase domain, including G1202R, I1171N, V1180L, and L1196M. Conclusions: Brigatinib showed clinically meaningful efficacy in Japanese patients refractory to prior alectinib (first line or post crizotinib), regardless of prior chemotherapy. The safety profile of brigatinib was consistent with prior studies and no new safety findings were identified. Clinical trial information: NCT03410108 . [Table: see text]