Cost-Effectiveness Analysis of Camrelizumab Plus Chemotherapy vs. Chemotherapy Alone as the First-Line Treatment in Patients With IIIB-IV Non-Squamous Non-Small Cell Lung Cancer (NSCLC) Without EGFR and ALK Alteration from a Perspective of Health - Care System in China

Abstract

Objective: The CAMEL clinical trial (412 patients were randomly assigned to either camrelizumab plus chemotherapy (n = 205) or chemotherapy alone (n = 207)) demonstrated that camrelizumab plus chemotherapy (CC) improved the overall survival time (OS) and progression-free survival time (PFS) of patients with metastatic nonsquamous non-small cell lung cancer (non-sq NSCLC) without epidermal growth factor receptor (EGFR) or anaplastic lymphoma kinase (ALK) mutations (EGFRm and ALKm) vs. chemotherapy (C) alone. Our objective was to conduct a cost-effectiveness analysis of CC vs. C from a perspective of health - care system in China with a lifetime horizon to identify whether it will be cost-effective. Materials and Methods: A partitioned survival model (PSM) was applied for patients with IIIB-IV non-sq NSCLC without EGFRm and ALKm. Transition parameters and proportions of three health states were derived from the CAMEL trial. The model was designed using a lifetime horizon, a 21-day cycle, and a 5% discount rate of costs and outcomes. It was deemed cost-effective in China if the incremental cost-effectiveness ratio (ICER) value is less than $32,457 per quality adjusted life-year (QALY). Deterministic and probabilistic sensitivity analyses were performed to verify the influence of parameter uncertainty on the results. Results: In the base-case analysis, we found that the ICER of CC compared with C is $-7,382.72/QALY which meant that CC had lower costs and better outcomes. The results of the sensitivity analyses demonstrated that the result was robust for the ICERs never transcending the willingness-to-pay (WTP) threshold. Conclusion: Camrelizumab plus chemotherapy is an obviously cost-effective therapeutic regime for patients of IIIB-IV non-sq NSCLC without EGFRm and ALKm in China at a $32,457 WTP threshold.

Keywords: CAMEL; NSCLC; camrelizumab; cost-effectiveness; nonsquamous non-small cell lung cancer.

FIGURE 1

Structure of the partitioned-survival model.

FIGURE 2

Parametric models for OS—camrelizumab plus chemotherapy. The log-normal model was chosen as the best fit model for the OS curve of the CC arm.

FIGURE 3

Parametric models for OS—chemotherapy. The log-logistic model was chosen as the best fit model for the OS curve of the C arm.

FIGURE 4

Parametric models for PFS—camrelizumab plus chemotherapy. The log-normal model was chosen as the best fit model for the PFS curve of the CC arm.

FIGURE 5

Parametric models for PFS—chemotherapy. The log-normal model was chosen as the best fit model for the PFS curve of the C arm.

FIGURE 6

Flowchart of treatment regime along with inclusion and exclusion criteria. Reference: CAMEL (NCT03134872) Protocol No.: SHR-1210-III-303-NSCLC.

FIGURE 7

Top 20 DSA results ranked by impact on ICER values.

FIGURE 8

Cost-effectiveness acceptability curves. The cost-effectiveness acceptability Frontier shows the probability of strategies being cost-effective in two strategies. Compared with chemotherapy alone, the probability of camrelizumab plus chemotherapy being cost-effective at the specified WTP threshold of $32,457 per QALY gained is nearly 100%.

FIGURE 9

Cost-effectiveness plane with scatter plot of incremental costs and incremental QALYs (WTP = $32,457). The results of Monte Carlo simulation of 1000 iterations show that in most cases camrelizumab and chemotherapy combination therapy generated more QALYs and less costs than chemotherapy alone.