Timely access to new drugs in a single-payer system: policy analysis from South Korea's reimbursement framework.

Background: Timely access to innovative medicines remains a policy challenge in single-payer systems. South Korea has introduced mechanisms such as economic evaluation exemptions and risk-sharing agreements (RSAs) to improve access while maintaining expenditure controls. However, empirical evidence on their real-world impact remains limited.

Research design and methods: A retrospective observational analysis was conducted using data on 85 new drugs assessed by the Health Insurance Review and Assessment Service (HIRA) between 2022 and 2024. Publicly available HTA datasets were categorized by evaluation outcome, pricing ratios, and projected budget impact. Statistical analyses included descriptive analysis, correlation testing, and multivariable linear regression.

Results: Eighty-two percent of assessed drugs were reimbursed. A full recommendation from HIRA strongly predicted listing outcomes. Drugs with moderate budget impact (1.5-10 billion Korean Won) experienced shorter timelines. International price ratios - averaging 64% of the mean level across reference countries - were the only consistent predictors across settings.

Conclusion: Evaluation outcomes, assessment complexity, and budget forecasts are key determinants of reimbursement in Korea. Refinement of HTA processes and adaptive use of RSAs may enhance access efficiency while preserving budgetary sustainability.