Abstract

Objectives

To determine the cost-effectiveness of second-line immune checkpoint inhibitors (ICIs) compared with chemotherapy in patients with advanced non-small cell lung cancer (NSCLC) using real-world patient-level treatment effectiveness, cost, and utility data.

Methods

Medical records of patients with NSCLC receiving second-line ICIs or chemotherapy at Siriraj Hospital, Bangkok, Thailand from January 2016 to May 2023 were reviewed to evaluate treatment effectiveness and direct medical costs. Patients receiving treatment from July 2023 to March 2024 were interviewed to determine utility and direct nonmedical costs. A semi-Markov model was used to analyze the lifetime costs and health outcomes from societal perspective. One-way and probabilistic sensitivity analyses and scenario analyses were performed.

Results

Data were collected from 209 patients (72 and 137 patients received second-line ICIs and chemotherapy, respectively). Second-line ICIs significantly improved overall survival (hazard ratio 0.64, 95% confidence interval 0.47-0.89, P = .008) and increased the quality-adjusted life-years (QALYs) from 0.54 to 1.11, resulting in QALY gain of 0.57; lifetime cost increased from 17 204 US dollar (USD) to 34 424 USD. Second-line ICI incremental cost-effectiveness ratio was 30 104 USD/QALY. Scenario analysis revealed that second-line ICIs were more cost-effective than chemotherapy for healthier patients (Eastern Cooperative Oncology Group 0-1) with incremental cost-effectiveness ratio of 9856 USD/QALY. Considering Thailand’s willingness-to-pay threshold of 4444 USD/QALY, second-line ICIs could be cost-effective if the cost of atezolizumab was reduced by 86%.

Conclusion

Second-line ICIs significantly improved survival in advanced NSCLC but are not cost-effective in Thailand. Drug price negotiation and patient subgroup prioritization would help make second-line ICIs more accessible.