Input parameters used in the model.

Background
Clinical trials have proven the efficacy and safety of atezolizumab combined with bevacizumab (A+B) in treating unresectable hepatocellular carcinoma (uHCC). This study aimed to assess the cost-utility of A+B compared to best supportive care (BSC) among uHCC patients in Thailand.
Methods
We conducted a cost-utility analysis from a societal perspective. We used a three-state Markov model to estimate relevant costs and health outcomes over the lifetime horizon. Local cost and utility data from Thai patients were applied. All costs were adjusted to 2023 values using the consumer price index. We reported results as incremental cost-effectiveness ratios (ICERs) in United States dollars ($) per quality-adjusted life year (QALY) gained. We discounted future costs and outcomes at 3% per annum. We then performed one-way sensitivity analysis and probabilistic sensitivity analysis to assess parameter uncertainty. The budget impact was conducted to estimate the financial burden from the governmental perspective over a five-year period.
Results
Compared to BSC, A+B provided a better health benefit with 0.8309 QALY gained at an incremental lifetime cost of $45,357. The ICER was $54,589 per QALY gained. The result was sensitive to the hazard ratios for the overall survival and progression-free survival of A+B. At the current Thai willingness-to-pay (WTP) threshold of $4,678 per QALY gained, the ICER of A+B remained above the threshold. The projected budgetary requirements for implementing A+B in the respective first and fifth years would range from 8.2 to 27.9 million USD.
Conclusion
Although A+B yielded the highest clinical benefit compared with BSC for the treatment of uHCC patients, A+B is not cost-effective in Thailand at the current price and poses budgetary challenges.