Factors Affecting Usage Levels and Trends of Innovative Oncology Drugs Upon and After Reimbursement Under Taiwan National Health Insurance: Interrupted Time Series Analysis

Abstract

Healthcare expenditure on pharmaceuticals, especially innovative oncology drugs, is escalating. Current knowledge on this topic is largely limited to studies conducted upon reimbursement of new drugs. We investigated how endogenous factors (e.g., changed reimbursement criteria, such as an expanded indication) and exogenous factors (e.g., competing drugs) affect the level and trends of innovative oncology drug utilization in the Taiwan National Health Insurance (NHI) system, both upon reimbursement and afterward. This retrospective longitudinal study analyzed monthly data (January 2009 to December 2014) from the NHI Research Database on the consumption (prescribing volume) of 15 innovative oncology drugs reimbursed by the NHI between 2007 and 2013. Effects of endogenous and exogenous factors on drug utilization were evaluated using interrupted time series analyses. In segmented regression analyses, changed drug prescribing volume after the indication expanded (endogenous factor) was statistically significant; however, drug volume did not change significantly after prescription restrictions changed. First-competitors and non-first-competitors (exogenous factors) were significantly associated with drug prescription levels or utilization rates. Taking sorafenib as an example, the post-reimbursement drug prescribing volume did not change significantly after its therapy line changed (endogenous factor), whereas the reimbursement of first-competitors (exogenous factor) was significantly associated with a lower level or usage rate of sorafenib. Utilization of innovative oncology drugs in Taiwan changed dramatically after NHI reimbursement, driven largely by expanded indications and new competitors. Drug utilization evaluations should investigate both endogenous and exogenous factors. The incidence of cancer is rising worldwide, 1-3 exacerbating substantial healthcare burdens, including high mortality and poor quality of life. Consequently, research and development of oncology drugs has increased in parallel to fulfil major unmet medical needs. 4-6 For example, innovative targeted therapy has revolutionized the treatment of metastatic renal

Effects of volume-based procurement policy on the usage and expenditure of first-generation targeted drugs for non-small cell lung cancer with EGFR mutation in China: an interrupted time series study

“…[22][23][24][25][26][27][28][29][30] As an active research field, the impact of NVBP policy on medicines such as antihypertensive drugs, 30 antiviral drugs 28 and antibiotics drugs 23 was reported, but the impact of the policy on the usage and expenditure of anticancer drugs was still unclear. Furthermore, although there were literature reports on the impact of other policies on the use of anticancer drugs, [31][32][33][34][35][36][37] the impact of the NVBP policy on cancer drugs was still unclear. Due to the lack of qualitative and quantitative evidence for the above effects, we conducted this exploratory study to evaluate the impact of the NVBP policy on the usage and expenditure of policy-related first-generation targeted drugs for NSCLC with EGFR mutations.…”

Prevalence of exposure to benzodiazepines among pregnant women in Taiwan: A nationwide longitudinal study

“…Taiwan started its National Health Insurance Programme in 1995 and has reached 99% coverage since 2004 (Lin, Gash, Smeeth, & Chen, 2018 ). This is a rich source of data for epidemiological and clinical research (Hsieh et al, 2019 ; Huang et al, 2021 ; Liao, Ko, Chen, & Hsiao, 2020 ; Sung, Hsieh, & Hu, 2020 ). The NHI system codes diagnoses using the International Classification of Diseases, Ninth Revision (ICD‐9) or Tenth Revision (ICD‐10).…”