ObjectivesIn December 2018, China launched national volume-based procurement (NVBP) to negotiate drug prices with manufacturers. Gefitinib was one of the 25 pilot drugs, which is used for treatment of non-small cell lung cancer. Lung cancer is the most common type of cancer in China and targeted drugs like gefitinib have been proven to provide clinical benefits to patients. This study aims to explore the impact of NVBP policy on the usage and expenditure of anticancer drugs.MethodsGefitinib and alternative drugs (icotinib and erlotinib) were used as objects of study. Quarterly data from the China Hospital Pharmaceutical Audit database in 9454 hospitals in China were used for analysis. Descriptive analysis was conducted using purchase volume and expenditure as variables. Interrupted time-series (ITS) analysis was applied to further analyse the effect of NVBP policy on the medicines under study.ResultsDuring the 12-month period before (2018Q2–2019Q1) and after (2019Q2–2020Q1) the NVBP policy, the total purchase volume of medicines rose from 4.48 million defined daily dose (DDD) to 7.02 million DDD, with an increase of 56.66%. Purchase volume of gefitinib and alternative drugs increased 100.61% and 14.88%, respectively. After the implementation of NVBP policy, procurement volume of alternative drugs decreased by 72 051 DDD (p value=0.044) and trend change decreased by 56 738 DDD (p value<0.01). The overall expenditure reduction was 14.7%, with the expenditure of gefitinib reducing by 38.47% and alternative drugs increasing by 10.70%. ITS analysis indicated statistically significant differences in level and trend changes for expenditure of total drugs and gefitinib.ConclusionsThe evidence provided in this study indicated that the implementation of NVBP policy was related to the expenditure reduction of the first generation of anti-EGFR lung cancer drugs. The policy effectively controlled the increase in expenditures for corresponding drugs while ensuring the use of drugs.