Cost-effectiveness analysis of atezolizumab as adjuvant treatment of patients with stage II-IIIA non-small cell lung cancer, PD-L1+≥50% of tumor cells in France: A modeling study

Abstract

IntroductionThe objective of this study was to assess the cost-effectiveness of atezolizumab versus best supportive care (BSC) as adjuvant treatment following resection and platinum-based chemotherapy for patients with stage II-IIIA non-small cell lung cancer (NSCLC) whose tumours have a programmed death-ligand 1 (PD-L1) expression ≥ 50% of tumour cells and excluding those with ALK/EGFR mutations, from a French collective perspective. Material and MethodsA five state Markov model over a 20-year time horizon was considered, including disease-free survival (DFS11Abbreviations: AE: adverse event; ALK: anaplastic lymphoma kinase; BSC: best supportive care; DFS: disease-free survival; DSA: deterministic sensitivity analyses; EFGR: epidermal growth factor receptor; EQ-5D: EuroQol-5 dimension; HAS: Haute Autorité de Santé; ICs: immune cells; ICER: incremental cost-effectiveness ratio; IgG1: immunoglobulin G1; IV: intravenous; KM: Kaplan-Meier; LY: life-year; NSCLC: non-small cell lung cancer; OS: overall survival; PD-L1: programmed death-ligand 1; PSA: probabilistic sensitivity analysis; QALY: quality-adjusted life-year; QoL: quality of life; TCs: tumor cells.) from IMpower010 trial, three progression states (locoregional recurrence, first and second-line metastatic recurrence) and death. Utilities, quality-adjusted life year (QALY) decrements associated to adverse events, costs, resource use, and transition probabilities were considered in the model. These inputs were sourced from IMpower010 trial, literature, and clinical experts’ opinion. Model uncertainty was assessed through deterministic, probabilistic sensitivity analyses and scenario analyses. ResultsAtezolizumab was associated with a QALY gain of 1.662, mainly driven by additional time spent in the DFS state, and a life-year gain of 2.112 years. The incremental cost-effectiveness ratio (ICER) for atezolizumab versus BSC was €21,348/QALY gained. The sensitivity analyses highlighted that uncertainty within the model had limited impact on results. Changing the DFS survival curves to other plausible distributions produced ICERs below €20,000/QALY. Introducing an increasing proportion of cured patients (91.5%) from year two to year five reduced the ICER to €13,083/QALY, while including a loss of efficacy at year two in the atezolizumab treatment arm increased the ICER to €33,755/QALY. DiscussionAtezolizumab as adjuvant treatment in stage II-IIIA NSCLC resected patients with PDL1 ≥ 50% and without ALK/EGFR mutations has a lower ICER than other oncology drugs in France and a similar ICER to other adjuvant treatment in oncology.