Cost-effectiveness analysis of adjuvant atezolizumab in stage II-IIIA non-small cell lung cancer expressing ≥50% PD-L1: A United Kingdom health care perspective

Abstract

ObjectivesAtezolizumab monotherapy has marketing authorisation by the Medicines and Healthcare products Regulatory Agency as adjuvant treatment following complete resection for adults with stage II–IIIA non-small cell lung cancer (NSCLC) whose tumours have PD-L1 expression on ≥ 50% of tumour cells and whose disease has not progressed following adjuvant platinum-based chemotherapy. This study evaluated the cost-effectiveness of atezolizumab vs best supportive care (BSC) in the licensed patient population from a UK perspective. Materials and MethodsPatient characteristics and clinical inputs were derived from the global, randomised, open-label, phaseIII IMpower010 trial. A Markov model with the following health states was developed: disease-free survival (DFS), locoregional recurrence, first-line metastatic recurrence, second-line metastatic recurrence, and death (all partitioned based on receipt of treatment, excluding death). The base case model used a lifetime time horizon (40 years) and 3.5% discounting annually after the first year. DFS from IMpower010 was analysed with parametric survival models to extrapolate outcomes for time points beyond trial follow-up. The models were adjusted to avoid overestimating results for patients with recurrences in the longer term. Grade ≥ 3 treatment-related adverse events with incidences ≥ 2% were included. Health state utility values were derived from the literature and past NICE appraisals. Sensitivity and scenario analyses assessed uncertainty around assumptions and parameter estimates. ResultsIn the base case analysis, atezolizumab therapy resulted in an expected gain of 1.87 quality-adjusted life-years (QALYs) corresponding to an incremental cost-effectiveness ratio of £20,392/QALY for atezolizumab vs BSC, demonstrating cost-effectiveness. Results were most influenced by discount effects and utility in the on-treatment DFS state. Scenario analyses were consistent with the base case results. ConclusionAtezolizumab after adjuvant chemotherapy is cost-effective for adults with NSCLC in the UK.