OA12.03 Initial Reporting of NRG-LU001, Randomized Phase II Trial of Concurrent Chemoradiotherapy +/- Metformin HCL in Locally Advanced NSCLC
Skinner H, Hu C, Tsakiridis T, Santana-Davila R, Lu B, Erasmus J, Doemer A, Videtic G, Coster J, Yang A, Lee R, Wasik MW, Schaner P, McCormack S, Esparaz B, McGarry R, Bazan J, Stuve T, and Bradley J. OA12.03 Initial Reporting of NRG-LU001, Randomized Phase II Trial of Concurrent Chemoradiotherapy +/- Metformin HCL in Locally Advanced NSCLC. J Thorac Oncol 2019; 14(10):S237-S238.
J Thorac Oncol
Background: Preclinical and retrospective clinical data, have shown that metformin, an inexpensive diabetes drug, has the potential to improve response to chemotherapy and radiation in several solid tumors, including non-small cell lung cancer (NSCLC). These findings led to NRG-LU001, a multi-institutional, international randomized Phase II clinical trial to determine whether metformin can improve outcomes of curative chemoradiation (CRT) in locally advanced NSCLC (LA-NSCLC). Method: Unresectable stage IIIA/B NSCLC patients were randomized to either concurrent chemoradiation to 60 Gy with weekly carboplatin-paclitaxel (CP), followed by consolidation CP (Control) or the same regimen combined with metformin (2000 mg/day) (Experimental). The primary endpoint was 1-year progression free survival (PFS). PFS and overall survival (OS) were estimated using the method of Kaplan-Meier. Time to loco-regional progression (TTLRP) or distant metastasis (TTDM) were estimated using the cumulative incidence method. Adverse events (AEs) were graded using CTCAE v4.0. Result: 170 patients were randomized between Aug. 2014-Dec. 2016, with planned analysis at 102 events. No significant difference in toxicity was observed between Control and Experimental arms. 1- and 2-year PFS was 60.4% (95% CI: 48.5, 70.4) and 40.1% (95% CI: 29.0, 51.0) in Control vs 51.3% (95% CI: 39.8, 61.7) and 34.5% (95% CI: 24.2, 45.1) in the Experimental arm (multivariable Cox proportional HR=1.20 (95% CI: 0.81, 1.78), p=0.36). On multivariable analysis including treatment arm, performance status, histology and stage, only higher stage (IIIA vs. IIIB) was associated with worse PFS (HR 1.79, 95% CI:1.19, 2.69, p=0.0054). OS at 2 years was 65.4% (95% CI: 53.5, 75.0) for Control vs 64.9% (95% CI: 53.1, 74.5) for the Metformin arm (HR=1.03 (95% CI: 0.64, 1.68)), while deaths due to disease were 90% vs 71%, respectively. No significant differences were found for TTLRP (HR 1.01, 95% CI: 0.57, 1.79, p=0.98) or TTDM (1.38, 95% CI: 0.76, 2.5, p=0.29). 63.4% of patients in the experimental arm received the complete course of metformin, with the most common cause of discontinuation being side effects or complications (13.4%). Conclusion: In NRG-LU001, concurrent CRT and metformin presented no noticeable safety concerns. However, this combination failed to improve PFS at the hypothesized effect size. Additionally, no effect on OS or patterns of failure were identified. Blinded central review of imaging based PFS is ongoing. Somewhat unexpectedly, 37% of patients did not complete the prescribed course of metformin. Additionally, deaths due to disease were less in the experimental arm compared to control. Acknowledgements: This project was supported by National Cancer Institute (NCI) grants: U10CA180868 (NRG Oncology Operations), U10CA180822 (NRG SDMC), UG1CA189867 (NCORP), U24CA180803 (IROC). HS and TT are Co-Principal Investigators in this trial. Keywords: clinical trial, chemoradiation, Lung cancer