Preliminary results of single arm phase 2 trial of brigatinib in patients (pts) with progression disease (PD) after next-generation (NG) anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) in ALK + non-small cell lung cancer (NSCLC).

Abstract

9027 Background: NG ALK TKIs are the standard first-line therapy for patients with advanced ALK + NSCLC. Brigatinib has activity against ALK resistance mutations and has CNS activity. The efficacy of brigatinib after NG ALK TKI is undetermined. Methods: Pts with stage IIIB/IV ALK + NSCLC, and PD after NG ALK TKI’s were eligible. Pts were required to have measurable disease, performance status 0-2, and adequate organ function. Pts were required to undergo tumor biopsy ≤ 60 days of enrollment; ctDNA was collected at baseline, at time of imaging, and PD. Brigatinib treatment was 90 mg daily for 7 days and then 180 mg daily (1 cycle = 28 days). Primary objective was objective response rate (ORR), and ORR of 20% was determined to be worthy of further investigation. Response was assessed every 2 cycles. A 2-stage design was used; if > 2 responses in 20 pts in the 1st stage, study proceeded to 2nd stage; if ≥ 5 responses in 40 pts therapy considered active. Results: Between 3/2017 and 11/2018, 20 pts were enrolled in the 1st stage. Pt characteristics were: median age 55 years (range 32 to 71), median number of prior therapies 3 (range 1 to 6), 12 had CNS disease at the baseline (8 pts had CNS PD). ALK resistance mutation detected in 3 of 8 pts on standard of care molecular testing. ORR results were confirmed partial response (n = 8), stable disease (n = 7), PD (n = 3), unconfirmed response (n = 1), and non-evaluable due adverse events (AE’s) (n = 1). The grade 3 or 4 AE’s were: pneumonitis (n = 2); 1 of each: acute renal failure, respiratory failure, sepsis, hypertension, CPK elevation, and headache. With median follow-up of 6.7 months (11 PFS events), the median PFS was 6.4 months (95% CI: 4.6 to NE). Overall survival data is immature. 3 of 3 pts with a known ALK mutation (F1174C in 2 pts, I1171T in 1 pt) responded, 2 of 5 pts without ALK mutation responded. Additional study related tumor analysis and ctDNA analyses are ongoing. Conclusions: Brigatinib has activity after progression on next generation ALK TKI. The study is enrolling additional patients in the second stage. Detailed molecular and site of disease (CNS versus extra-CNS) activity analyses are underway Clinical trial information: NCT02706626.