Similarity between generic and brand-name antihypertensive drugs for primary prevention of cardiovascular disease: evidence from a large population-based study.

Abstract

Although generic and earlier brand-name counterparts are bioequivalent, their equivalence in preventing relevant clinical outcomes is of concern. To compare effectiveness of generic and brand-name antihypertensive drugs for preventing the onset of cardiovascular (CV) outcomes. A population-based, nested case-control study was carried out by including the cohort of 78520 patients from Lombardy (Italy) aged 18years or older who were newly treated with antihypertensive drugs during 2005. Cases were the 2206 patients who experienced a hospitalization for CV disease from initial prescription until 2011. One control for each case was randomly selected from the same cohort that generated cases. Logistic regression was used to model the CV risk associated with starting on and/or continuing with generic or brand-name agents. There was no evidence that patients who started on generics experienced different CV risk than those on brand-name product (OR 0·86; 95% CI 0·63-1·17). Patients at whom generics were main dispensed had not significantly difference in CV outcomes than those mainly on brand-name agents (OR 1·19; 95% CI 0·86-1·63). Compared with patients who kept initial brand-name therapy, those who experienced brand-to-generic or generic-to-brand switches, and those always on generics, did not show differential CV risks, being the corresponding ORs (and 95% CIs), 1·18 (0·96-1·47), 0·87 (0·63-1·21) and 1·08 (0·80-1·46). Our findings do not support the notion that brand-name antihypertensive agents are superior to generics for preventing CV outcomes in the real-world clinical practice.