To reduce drug prices and improve access to essential medicines, the Chinese government implemented the National Volume‐Based Procurement (NVBP) policy, leveraging economies of scale. Montelukast sodium, widely prescribed for respiratory diseases, was included in the first round. This study evaluates the impact of the NVBP policy, offering insights for global pharmaceutical policy reform.

Utilizing national procurement data from the National Healthcare Security Administration (January 2019 to December 2020), we conducted an interrupted time‐series analysis, employing autoregressive integrated moving average models to correct for autocorrelation. We evaluated changes in procurement volume (in defined daily doses), procurement expenditures, and defined daily dose costs of montelukast sodium before and after NVBP implementation.

The NVBP policy triggered a substantial decline in total procurement expenditures and defined daily dose costs, significantly improving drug affordability. Unlike the volume surge observed in other NVBP‐covered drugs, the total procurement volume of montelukast sodium remained stable, suggesting rational clinical demand. Structurally, the policy successfully drove a “generic substitution” effect, where bid‐winning generics rapidly replaced high‐priced originators. The market share of non‐equivalent generics contracted significantly, marking a quality consolidation of the market.

The NVBP successfully achieved cost containment for chronic respiratory disease medications. By promoting high‐quality generic substitution and reducing the market share of high‐priced originators and low‐quality generics, the policy effectively optimized the market structure. These findings provide a replicable China Model for low‐ and middle‐income countries seeking to balance affordability and accessibility in chronic disease management.

Atherosclerotic cardiovascular disease remains the leading cause of death worldwide. This study aims to explore the impact of national volume‐based procurement (NVBP) on Chinese patent medicines and provide evidence for improving policies and promoting rational drug use.

The study was based on data from the China National Health Insurance Agency that spanned January 2019 to December 2020. Descriptive analysis was conducted using volume and expenditure as variables. Interrupted time series analysis was applied to further analyze Chinese patent medicines.

The unit prices of atorvastatin and rosuvastatin decreased by 25%–96%, whereas the prices of Zhibitai and Xuezhikang fluctuated slightly. The affordability is measured as the monthly expenditure on treatment divided by the daily wage. After policy implementation, the affordability of atorvastatin and rosuvastatin improved from 0.242 to 0.014 and from 0.247 to 0.019, respectively. The defined daily doses (DDDs) for atorvastatin and rosuvastatin also increased, whereas total expenditures decreased in hospitals of all levels. Both at the national level and at all levels of hospital, the policy had no significant impact on expenditures for Zhibitai and Xuezhikang and their defined daily doses.

The NVBP saved costs in the short term by incorporating high‐quality, widely used lipid‐lowering drugs. Notably, the policy impacted lipid‐lowering chemical drugs, whereas Chinese patent medicines remained largely unaffected. Doctors' use of Chinese patent medicines did not decline, highlighting the clinical specificity of these medicines.