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

Abstract

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. 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. 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. Incremental cost-effectiveness ratios were compared with a willingness-to-pay threshold of $100 000 per quality-adjusted life-year (QALY). 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 $112 551 (95% CI, $112 450-$112 653) 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 $244 166 (95% CI, $243 864-$244 468) 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 $201 676 per QALY (95% CI, $198 105-$205 355 per QALY). In base case 2, in which 1 million patients were simulated, pembrolizumab combination therapy was associated with a mean cost of $226 282 (95% CI, $226 007-$226 557) 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 $116 698 per QALY (95% CI, $115 088-$118 342 per QALY) between pembrolizumab combination and bevacizumab, carboplatin, and paclitaxel. Atezolizumab combination was not cost-effective at a willingness-to-pay threshold of $100 000 per QALY. 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.