Clinical question: Does switching from a brand name ARB to its generic lead to more ED visits and hospitalizations?
Background: Once a brand name drug’s patent expires, its generic form is commercialized and patients may be switched to the generic version. The drug equivalence of the generic vs. the brand name product may be substantial enough to affect clinically what is happening to the patient. Very few studies exist on the impact of the differences between brand-name and generic ARBs; those that do exist show conflicting results on clinical outcomes for the patient.
Study design: Observational retrospective interrupted time–series analysis.
Setting: Quebec Integrated Chronic Disease Surveillance System in Quebec.
Synopsis: The study analyzed 136,177 patients older than 66 years old with multiple comorbidities during the transition from brand-name to generic versions of losartan, valsartan, and candesartan. The authors compared ER visits or hospitalization of the brand-name users for 24 months before and 12 months after being transitioned from a brand-name ARB to a generic. All three groups were found to have higher rates of adverse events after switching to generics (8% for losartan, 11.7% for valsartan, and 16.6% for candesartan). The study was limited as the authors did not have access to the reason for the ER visits/admissions or the ability to determine which generic version was used (e.g., losartan has eight generic versions). The study highlights the need for further evaluation by risk and survival analysis to control confounders when switching to a generic formulation.
Bottom line: Switching patients from a brand-name to a generic ARB may lead to more ED consultations and hospital admissions.
Citation: Leclerc J et al. Impact of the commercialization of three generic angiotensin II receptor blockers on adverse events in Quebec Canada. Circ Cardiovasc Qual Outcomes. 2017 Oct 3. pii 10e003891. doi: 10.1161/circoutcomes.117.003891.
Dr. Smith is assistant professor of medicine in the Division of Hospital Medicine, Emory University, Atlanta.