Details
In 2018, North American and European drug regulatory agencies notified the public about recalls of valsartan and certain other angiotensin II receptor blocker (ARB) products after discovering the presence of potential carcinogenic nitrosamine impurities, N-nitrosodimethylamine (NDMA) and N-nitrosodiethylamine (NDEA), in the products. Collaborating with international institutions, we examined valsartan and other angiotensin receptor blocker (ARB) utilization and switching patterns in the United States, United Kingdom, Canada (described below), and Denmark to evaluate the impacts of the recalls due to nitrosamine impurities.
This analysis was conducted utilizing the Canadian Network for Observational Drug Effect Studies (CNODES) and includes four reports summarizing data obtained from the CNODES. The study period for Report 1 includes data from January 1, 2014, to December 31, 2020. The study period for Reports 2-4 includes data from May 1, 2012, to December 31, 2020:
- Report 1: We estimated the proportion of individual ARB-containing product use and the proportion of patients who switched from a primary ARB to another individual ARB over time. We distributed this request to the CNODES on January 28, 2022.
- Report 2: We estimated the incident utilization for all, branded, impurity identified, no impurity identified, recalled, and unclassified valsartan, and recalled ARBs over time. We distributed this request to the CNODES on July 29, 2022.
- Report 3: We estimated the prevalent utilization for all, branded, impurity identified, no impurity identified, recalled, and unclassified valsartan, and recalled ARBs over time. We distributed this request to the CNODES on July 29, 2022.
- Report 4: We estimated the proportion of switching between categories of branded valsartan products and valsartan products with nitrosamine impurities or without nitrosamine impurities among prevalent users of branded valsartan products and valsartan products with nitrosamine impurities or without nitrosamine impurities. Switching is defined as the detection of a valsartan dispensing of another category within the exposure valsartan episode. We distributed this request to the CNODES on July 29, 2022.
Analyses were also conducted in the Sentinel Distributed Database (SDD), Danish National Prescription Registry (DNPR), and Clinical Practice Research Datalink (CPRD). A list of the results by country can be found in the Additional Information tab.