Cost-Effectiveness Analysis of Atezolizumab Versus Chemotherapy as First-Line Treatment for Metastatic Non-Small-Cell Lung Cancer With Different PD-L1 Expression Status

Abstract

Background: Atezolizumab could significantly improve clinical outcomes and was associated with less toxicity compared with chemotherapy as the first-line treatment of PD-L1-selected patients with EGFR and ALK wild-type metastatic non-small-cell lung cancer (NSCLC). However, the economic outcomes remain unclear yet in China. This study aimed to investigate the cost-effectiveness of atezolizumab versus chemotherapy as first-line therapy for metastatic NSCLC with different PD-L1 expression status from the Chinese health sector perspective.

Methods: A decision-analytic model was conducted to evaluate the economic outcomes for the first-line treatment of EGFR and ALK wild-type metastatic NSCLC with atezolizumab and chemotherapy in high PD-L1 expression, high or intermediate PD-L1 expression and any PD-L1 expression populations, respectively. The efficacy and safety data were obtained from the IMpower110 trial. Cost and utility values were gathered from the local charges and published literatures. Incremental cost-effectiveness ratio (ICER) was estimated. A scenario analysis for a patient assistance program (PAP) was conducted. One-way and probabilistic sensitivity analyses were performed to explore the robustness of the model results.

Results: Atezolizumab yielded additional 0.91 QALYs, 0.57 QALYs, 0.42 QALYs in comparison with chemotherapy, and the ICERs were $123,778.60/QALY, $142,827.19/QALY, $168,902.66/QALY in the high PD-L1 expression, high or intermediate PD-L1 expression, and any PD-L1 expression populations, respectively. When PAP was available, the ICERs were $52,414.63/QALY, $52,329.73/QALY, $61,189.66/QALY in the three categories of PD-L1 expression status populations, respectively. The ICERs were exceed the willingness-to-pay (WTP) threshold of $30,828/QALY (three times of per capita gross domestic product of China in 2019) in China. One-way sensitivity analyses suggested that the cost of atezolizumab played a vital role in the model outcomes, and the probabilistic sensitivity analyses showed atezolizumab was unlikely to be cost-effective at the WTP threshold regardless of PD-L1 expression status and whether the PAP was available or not.

Conclusions: Atezolizumab as first-line treatment for PD-L1-selected metastatic NSCLC patients without EGFR mutations or ALK translocations is unlikely to be cost-effective compared with chemotherapy regardless of PD-L1 expression status in the Chinese context.

Keywords: atezolizumab; chemotherapy; cost-effectiveness; first-line treatment; non-small-cell lung cancer.

Figure 1

The structure of the (A) decision tree and (B) Markov model. NSCLC, non-small-cell lung cancer.

Figure 2

The comparison between the adopted fitting curves and the Kaplan-Meier (KM) curves in IMpower110 trial. PFS, progression-free survival; OS, overall survival; PD-L1, programmed death ligand 1.

Figure 3

Tornado diagram of one-way sensitivity analyses with greatest influence parameters when the PAP was not available in (A) high PD-L1 expression populations, (B) high or intermediate PD-L1 expression populations and (C) any PD-L1 expression populations. PD-L1, programmed death ligand 1; PFS, progression-free survival; PD, progressed disease; ICER, incremental cost-effectiveness ratio.

Figure 4

Tornado diagram of one-way sensitivity analyses with greatest influence parameters when the PAP was available in (A) high PD-L1 expression populations, (B) high or intermediate PD-L1 expression populations and (C) any PD-L1 expression populations. PD-L1, programmed death ligand 1; PFS, progression-free survival; PD, progressed disease; WTP, willingness-to-pay; ICER, incremental cost-effectiveness ratio.

Figure 5

Cost-effectiveness acceptability curves of atezolizumab versus chemotherapy when the PAP was not available for (A) high PD-L1 expression populations, (B) high or intermediate PD-L1 expression populations and (C) any PD-L1 expression populations. PD-L1, programmed death ligand 1.

Figure 6

Cost-effectiveness acceptability curves of atezolizumab versus chemotherapy when the PAP was available for (A) high PD-L1 expression populations, (B) high or intermediate PD-L1 expression populations and (C) any PD-L1 expression populations. PD-L1, programmed death ligand 1.