The impact of National Centralised Drug Procurement policy on the use of policy‐related original and generic drugs in China

To evaluate the effects of the first round of National Centralised Drug Procurement pilot (so-called '4+7' policy) on the use of policy-related original and generic drugs.This study used drug purchasing order data from the Centralised Drug Procurement Survey in Shenzhen 2019, covering 24 months from January 2018 to December 2019. '4+7' policy-related drugs were selected as study samples, including 25 drugs in the '4+7' procurement list and 69 alternative drugs that have an alternative relationship with '4+7' List drugs in clinical use. '4+7' List drugs were then divided into bid-winning and bid-non-winning products according to the bidding results. Included drugs were sorted into original and generic drugs. Purchase volume, expenditures, and daily costs were selected as outcome variables, and were measured using Defined Daily Doses (DDDs), Chinese Yuan (CNY), and Defined Daily Drug cost (DDDc). A single-group Interrupted Time Series analysis was adopted to quantify policy effect.After policy intervention, the overall policy-related original drugs significantly decreased by 0.39 CNY (95% CI: -0.62 to -0.17, p < 0.01) in DDDc, 5949.36 thousand DDDs (95% CI: -8276.67 to -3622.05, p < 0.001) in volume, and 31,575.08 thousand CNY (95% CI: -41,812.68 to -21,337.49, p < 0.001) in expenditures. The volume proportion of generic drugs increased from 78.6% to 91.0%, and the expenditure proportion of increased from 30.9% to 49.8%.'4+7' policy promoted the substitution use of domestic generics against original branded drugs and played positive effects on drug price cut and medication burden reduction. The proportion of original branded drugs and generics that passed generic consistency evaluation significantly increased after policy intervention, indicating the improvement of the overall quality level of drug use in China.