In December 2008, the Journal of the American Medical Association published an article on the clinical equivalence of generic and brand-name drugs used in cardiovascular disease by Aaron Kesselheim, et al. of Harvard Medical School, Boston, MA, USA.
Branded cardiovascular drugs not better than generics
Generics/Research | Posted 29/07/2009 0 Post your comment
Use of generic drugs, which are bioequivalent to brand-name drugs, can help contain prescription drug spending. However, there is concern among patients and physicians that brand-name drugs may be clinically superior to generic drugs. The objective was to summarise clinical evidence comparing generic and brand-name drugs used in cardiovascular disease and to assess the perspectives of editorialists on this issue.
Systematic searches of peer-reviewed publications were performed in MEDLINE, EMBASE, and International Pharmaceutical Abstracts from January 1984 to August 2008. Studies compared generic and brand-name cardiovascular drugs using clinical efficacy and safety end points. Editorials addressing generic substitution and extracted variables related to the study design, setting, participants, clinical end points, and funding were separately identified. Methodological quality of the trials was assessed by Jadad and Newcastle-Ottawa scores, and a meta-analysis was performed to determine an aggregate effect size. For editorials, authors' positions on generic substitution were categorised as negative, positive, or neutral.
Kesselheim, et al. identified 47 articles covering 9 subclasses of cardiovascular medications, of which 38 (81%) were randomised controlled trials (RCTs). Clinical equivalence was noted in 7 of 7 RCTs (100%) of beta-blockers, 10 of 11 RCTs (91%) of diuretics, 5 of 7 RCTs (71%) of calcium channel blockers, 3 of 3 RCTs (100%) of antiplatelet agents, 2 of 2 RCTs (100%) of statins, 1 of 1 RCT (100%) of angiotensin-converting enzyme inhibitors, and 1 of 1 RCT (100%) of alfa-blockers. Among narrow therapeutic index drugs, clinical equivalence was reported in 1 of 1 RCT (100%) of class 1 anti-arrhythmic agents and 5 of 5 RCTs (100%) of warfarin. Aggregate effect size (n = 837) was –0.03 (95% confidence interval, –0.15 to 0.08), indicating no evidence of superiority of brand-name to generic drugs. Among 43 editorials, 23 (53%) expressed a negative view of generic drug substitution.
The conclusion was that, whereas evidence does not support the notion that brand-name drugs used in cardiovascular disease are superior to generic drugs, a substantial number of editorials counsel against the interchangeability of generic drugs.
Source: JAMA. 2008;300(21):2514-26.