Cost-effectiveness of Atezolizumab Combination Therapy for First-Line Treatment of Metastatic Nonsquamous Non-Small Cell Lung Cancer in the United States

Importance: Immune checkpoint inhibitor combination therapy has recently become the standard of care for first-line treatment of metastatic nonsquamous non-small cell lung cancer. The implications of these first-line treatments are considerable, given the potential population of patients eligible to receive them and their high cost. Objective: To evaluate the cost-effectiveness of adding atezolizumab to bevacizumab, carboplatin, and paclitaxel as a first-line treatment strategy for patients with metastatic nonsquamous non-small cell lung cancer in the United States. Design, Setting, and Participants: In this economic evaluation, a primary microsimulation model was developed to assess atezolizumab combination vs bevacizumab, carboplatin, and paclitaxel alone in the first line (base case 1). A secondary model was developed to assess these treatments along with pembrolizumab combination and platinum doublet chemotherapy (base case 2). Treatment strategies and other simulated conditions were based on those from the IMpower150 and KEYNOTE-189 clinical trials. The study perspective was the US health care sector. One million patients with metastatic nonsquamous non-small cell lung cancer were simulated for each treatment group. This study was performed from February 2019 through May 2019. Main Outcomes and Measures: Incremental cost-effectiveness ratios were compared with a willingness-to-pay threshold of $100000 per quality-adjusted life-year (QALY). Results: In base case 1, in which 1 million patients were simulated, treating with bevacizumab, carboplatin, and paclitaxel in the first line was associated with a mean cost of $112551 (95% CI, $112450-$112653) and a mean survival of 1.48 QALYs (95% CI, 1.47-1.48 QALYs) per patient. Atezolizumab plus bevacizumab, carboplatin, and paclitaxel was associated with a mean cost of $244166 (95% CI, $243864-$244468) and a mean survival of 2.13 QALYs (95% CI, 2.12-2.13 QALYs) per patient, for an estimated incremental cost-effectiveness ratio of $201676 per QALY (95% CI, $198105-$205355 per QALY). In base case 2, in which 1 million patients were simulated, pembrolizumab combination therapy was associated with a mean cost of $226282 (95% CI, $226007-$226557) and a mean survival of 2.45 QALYs (95% CI, 2.44-2.46 QALYs) per patient. Pembrolizumab combination dominated atezolizumab plus bevacizumab, carboplatin, and paclitaxel, leading to an incremental cost-effectiveness ratio of $116698 per QALY (95% CI, $115088-$118342 per QALY) between pembrolizumab combination and bevacizumab, carboplatin, and paclitaxel. Atezolizumab combination was not cost-effective at a willingness-to-pay threshold of $100000 per QALY. Conclusions and Relevance: In this simulated model economic analysis, atezolizumab combination was not cost-effective compared with bevacizumab, carboplatin, and paclitaxel and provided suboptimal incremental benefit compared with cost vs pembrolizumab combination for first-line treatment. Although atezolizumab combination therapy provides clinical benefits, price reductions may be necessary for this treatment strategy to become cost-effective.