[Ip-health] JAMA: Clinical Equivalence of Generic and Brand-Name Drugs Used in Cardiovascular Disease

[Sam Houshower]

"Conclusions[:]  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."
_________

[ABSTRACT]

http://jama.ama-assn.org/cgi/content/abstract/300/21/2514

Clinical Equivalence of Generic and Brand-Name Drugs Used in
Cardiovascular Disease
A Systematic Review and Meta-analysis

Aaron S. Kesselheim, MD, JD, MPH; Alexander S. Misono, BA; Joy L. Lee,
BA; Margaret R. Stedman, MPH; M. Alan Brookhart, PhD; Niteesh K.
Choudhry, MD, PhD; William H. Shrank, MD, MSHS

JAMA. 2008;300(21):2514-2526.

Context  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.

Objectives  To summarize clinical evidence comparing generic and brand-
name drugs used in cardiovascular disease and to assess the
perspectives of editorialists on this issue.
Data Sources  Systematic searches of peer-reviewed publications in
MEDLINE, EMBASE, and International Pharmaceutical Abstracts from
January 1984 to August 2008.

Study Selection  Studies compared generic and brand-name
cardiovascular drugs using clinical efficacy and safety end points. We
separately identified editorials addressing generic substitution.

Data Extraction  We extracted variables related to the study design,
setting, participants, clinical end points, and funding.
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, we categorized
authors' positions on generic substitution as negative, positive, or
neutral.

Results  We identified 47 articles covering 9 subclasses of
cardiovascular medications, of which 38 (81%) were randomized
controlled trials (RCTs). Clinical equivalence was noted in 7 of 7
RCTs (100%) of =CE=B2-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 -
blockers. Among narrow therapeutic index drugs, clinical equivalence
was reported in 1 of 1 RCT (100%) of class 1 antiarrhythmic agents and
5 of 5 RCTs (100%) of warfarin. Aggregate effect size (n =3D 837) was =E2=
=80=93
0.03 (95% confidence interval, =E2=80=930.15 to 0.08), indicating no eviden=
ce
of superiority of brand-name to generic drugs. Among 43 editorials, 23
(53%) expressed a negative view of generic drug substitution.

Conclusions  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.


Author Affiliations: Division of Pharmacoepidemiology and
Pharmacoeconomics, Department of Medicine, Brigham and Women's
Hospital, Harvard Medical School, Boston, Massachusetts.