Abstract B23: Cost-effectiveness analysis of VeriStrat® selection criteria for EGFR inhibitor therapy for previously treated patients with NSCLC

Abstract

Abstract Background: EGFR inhibitor therapy extends survival as 2nd or 3rd line treatment of patients with previously treated metastatic non-small cell lung cancer (NSCLC), but a randomized trial of 2nd line therapy in unselected patients showed similar benefit versus conventional chemotherapy. EGFR mutation analysis is useful in choosing therapy, but it is applicable to only a minority of patients due to low frequency of mutation in North America and ignores the majority of patients who may benefit with wild type status. Alternative selection strategies are needed. VeriStrat is a protein expression profile utilizing matrix-assisted laser desorption/ionization time of flight mass spectrometry to analyze serum. The test classifies patients as either VeriStrat Good or VeriStrat Poor based on likelihood of benefitting from EGFR inhibitor therapy. The objective of this research was to model the anticipated survival and cost analysis of patients using a Veristrat Selection Strategy for 2nd line therapy of NSCLC to the alternative treatment strategies of chemotherapy for all (Chemo-all), EGFR inhibitor to all (EGFR-all), or to performance status selection (PS selection), a common practice, where those with good PS receive chemotherapy and those with poor PS receive EGFR inhibitor therapy. Methods: We developed a Markov model using US health care system perspective. Model inputs, taken from published literature, for the base-case analysis (and ranges) were the following: PS good, 50% (35%–65%); VeriStrat Good, 60% (45%–75%); VeriStrat Good if PS bad, 40% (25%–55%); survival on EGFR inhibitor if VeriStrat Good, 10.5 months (8–12); 1-year survival on EGFR inhibitor if VeriStrat Good, 47% (43–50); 1-year survival on EGFR inhibitor if VeriStrat Poor, 12% (8–16) and 1-year survival on chemotherapy, 29% (23–35); cost of EGFR inhibitor, $3,125/month ($2,813–$3,438); cost of chemotherapy, $1,324/vial ($1,192–$1,457); cost of VeriStrat test, $2,860 ($1,000–$5,000). Effectiveness outcome was quality-adjusted life years (QALYs). Probabilistic sensitivity analysis was performed using 10,000 2nd order Monte Carlo simulations. Results: In the base case analysis, the PS selection and E-all strategies were eliminated due to extended dominance (i.e. both more costly and less effective, on average, than a linear combination of other strategies in model) and the VeriStrat selection strategy had the highest average effectiveness (.886 QALYs). The incremental cost-effectiveness ratio (ICER) for VeriStrat selection compared to the C-all strategy was $66,381/QALY. Probabilistic sensitivity analysis revealed that VeriStrat selection was most often the most cost-effective strategy for willingness to pay levels > $76,000. Conclusion: These results quantify the trade-off between increased cost and improved effectiveness of a new method for selecting treatment for patients with metastatic NSCLC and provide valuable information to help providers decide whether or not to adopt this new technology. Historically, a threshold of $50,000/QALY has been cited as the cutoff for cost-effectiveness. Recently, however, health economics experts have advocated increasing this threshold to $100,000/QALY. Based on this $100,000/QALY cutoff, VeriStrat selection appears to be a cost-effective treatment strategy for 2nd or 3rd line treatment of patients with previously treated metastatic NSCLC.