To systematically evaluate reimbursement access, reimbursement restrictions, and provincial “dual-channel” coverage of drugs for rare diseases in China in the context of successive updates to China’s National Reimbursement Drug List (NRDL). The study further aimed to characterize temporal changes in both the breadth and timeliness of reimbursement access, examine the concordance between regulatory-approved indications and reimbursement restrictions, and quantify interprovincial variation in “dual-channel” coverage, thereby providing evidence to inform the continued optimization of healthcare security policies for rare-disease drugs and improve patient access to treatment.

Diseases included in China’s two national rare disease lists were defined as the study scope. Annual editions of China’s National Reimbursement Drug List (NRDL), together with relevant national drug-negotiation documents, were systematically reviewed for the period from 2018 to 2025. Rare-disease treatment indications were identified with reference to the reimbursement restrictions specified in the NRDL, and disease–drug pairs were established accordingly. For each study year, the numbers of NRDL-listed rare-disease drugs, rare diseases with reimbursed treatment options, and corresponding disease–drug pairs were summarized to characterize longitudinal changes in the breadth of reimbursement coverage.

To evaluate the timeliness of reimbursement access, reimbursement access lag was defined as the interval between the approval date of the relevant rare-disease indication and the earliest date on which the corresponding drug was included in the NRDL. Negative intervals were excluded from the access-lag analysis. Annual means, medians, and quartiles were calculated to describe the distribution and temporal evolution of the interval from indication approval to reimbursement access. This analysis complemented the assessment of expansion in reimbursement coverage by capturing changes in the time required for approved rare-disease indications to obtain national reimbursement status.

Regulatory-approved indications stated in drug labeling were additionally compared with NRDL reimbursement restrictions to assess the concordance between approved indications and the effective scope of reimbursement coverage. The analysis also identified the principal forms of additional reimbursement criteria, including restrictions related to patient age, disease subtype, disease severity, line of therapy, and previous treatment where applicable.

In addition, provincial “dual-channel” policies and drug lists were collected for all 31 provinces, autonomous regions, and municipalities in mainland China. Using rare-disease drugs included in the 2025 NRDL as the reference set, the numbers of rare-disease drugs incorporated into provincial “dual-channel” mechanisms and the corresponding rare diseases covered were summarized. Descriptive statistics, including means, medians, minimum–maximum values, and ranges, were used to quantify interprovincial differences in the breadth of “dual-channel” coverage.

Between 2018 and 2025, the scope of national reimbursement coverage for rare-disease drugs expanded substantially. The number of rare-disease drugs covered by the NRDL increased from 46 in 2018 to 114 in 2025, while the number of rare diseases with reimbursed treatment options increased from 29 to 64. Over the same period, the number of disease–drug pairs increased from 53 to 133. Collectively, these findings demonstrate a marked expansion in both the number of reimbursed therapeutic options and the range of rare diseases represented within the national reimbursement system.

The time from indication approval to reimbursement access also decreased substantially over the study period. After exclusion of negative intervals, the median reimbursement access lag decreased from 66 months in 2018 to 17 months in 2025, corresponding to an absolute reduction of 49 months and a relative reduction of 74.2%. The mean reimbursement access lag decreased from 86.19 months to 32.66 months, representing an absolute reduction of 53.53 months and a relative reduction of 62.1%. The consistent reductions observed in both the median and mean measures indicate an overall shortening of the interval between regulatory approval of a rare-disease indication and subsequent access to national reimbursement.

Among the 133 disease–drug pairs identified in 2025, 71.4% were subject to explicit reimbursement restrictions, whereas 28.6% had no explicit reimbursement restrictions. Overall, reimbursement coverage was generally concordant with the regulatory-approved indications stated in drug labeling. For a subset of drugs, however, the effective scope of reimbursement was further specified through eligibility criteria relating to patient age, disease subtype, disease severity, line of therapy, or previous treatment. These criteria therefore further delineated the reimbursable patient population and clinical circumstances within the boundaries of the approved indication.

Substantial interprovincial variation was observed in the coverage of rare-disease drugs under provincial “dual-channel” mechanisms. Across the 31 provincial-level regions, the mean number of included rare-disease drugs was 57, covering a mean of 40 rare diseases; the corresponding medians were 62 drugs and 41 diseases. The number of rare-disease drugs included in provincial “dual-channel” mechanisms ranged from 10 to 75, corresponding to a range of 65 drugs. The number of rare diseases covered ranged from 12 to 50, corresponding to a range of 38 diseases. These results indicate persistent heterogeneity in the breadth of provincial “dual-channel” coverage after drugs have obtained national reimbursement status.

Successive updates to China’s NRDL have substantially expanded reimbursement coverage for rare-disease drugs and increased the number of rare diseases with reimbursed treatment options. Concurrently, the reimbursement access lag from indication approval to NRDL inclusion has generally shortened, reflecting a marked reduction in the time between regulatory approval and national reimbursement access over the study period. Reimbursement restrictions were broadly concordant with approved indications, while additional eligibility criteria further defined the effective scope of reimbursement for some drugs. Despite national reimbursement access, considerable interprovincial variation remains in the coverage of rare-disease drugs under provincial “dual-channel” mechanisms. Greater coordination among national reimbursement access, reimbursement restrictions, and provincial “dual-channel” policies is therefore warranted. Post-listing coverage and monitoring mechanisms should also be strengthened to facilitate the effective supply and rational use of NRDL-listed rare-disease drugs in clinical practice and, ultimately, improve patient access to appropriate rare-disease therapies.