American Heart Association
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Generic clopidogrel is noninferior to the brand-name antiplatelet drug Plavix, according to research published in Circulation: Cardiovascular Quality and Outcomes.
When a Canadian health system switched from prescribing Plavix to generic clopidogrel, patients with acute coronary syndrome (ACS) were no more likely to die or experience ACS recurrence within a year.
In addition, there were no significant differences between the Plavix and clopidogrel groups in the percentage of patients who were hospitalized for any reason, had a stroke or transient ischemic attack, or experienced bleeding.
“People can safely use generic clopidogrel,” said study author Dennis T. Ko, MD, of the Institute for Clinical Evaluative Sciences in Toronto, Ontario, Canada.
“This large and real-world study should be reassuring to physicians and healthcare organizations who have been concerned about changing what is prescribed.”
Dr Ko and his colleagues compared outcomes in patients who were prescribed clopidogrel after hospitalization for ACS in Ontario, Canada, where the Ministry of Health began to automatically substitute generic clopidogrel for Plavix once the brand name drug’s patent expired in 2012.
Between 2009 and 2014, 12,643 patients were prescribed Plavix, and 11,887 were prescribed generic clopidogrel.
“There are quite a few different generic brands,” said study author Cynthia Jackevicius, PharmD, of Western University of Health Sciences in Pomona, California.
“In this study, we considered them as a group but later found no differences in outcome when we compared between different generics.”
Results
The study’s primary outcome—a composite of death and hospitalization for ACS at 1 year—was met by 17.6% of patients prescribed Plavix and 17.9% of patients prescribed clopidogrel. The hazard ratio (HR) was 1.02 (95% confidence interval [CI], 0.96–1.08; P=0.005 for noninferiority, P=0.619 for superiority).
The 1-year mortality rate was 10.5% in the Plavix group and 11.2% in the clopidogrel group (HR=1.07; 95% CI, 0.99–1.15, P=0.210 for noninferiority, P=0.114 for superiority).
And hospitalization for ACS occurred in 9.7% and 9.2%, respectively (HR=0.94; 95% CI, 0.87–1.03, P<0.001 for noninferiority, P=0.190 for superiority).
Hospitalization for any reason occurred in 39.4% of patients in the Plavix group and 39.8% of those in the clopidogrel group (HR=1.02; 95% CI, 0.97–1.06, P<0.001 for noninferiority, P=0.482 for superiority).
Hospitalization for stroke or transient ischemic attack occurred in 1.5% and 1.4%, respectively (HR=0.92; 95% CI, 0.74–1.15, P=0.056 for noninferiority, P=0.455 for superiority).
And hospitalization for bleeding occurred in 2.3% and 2.7%, respectively (HR=1.17; 95% CI, 0.99–1.39, P=0.772 for noninferiority, P=0.063 for superiority).
The researchers noted that, in 2010, Plavix cost about $2.58 Canadian dollars per pill. It was projected to cost the Ontario Drug Benefit Program $72.8 million by 2012.
By switching to generic clopidogrel, which costs $0.39 per pill in 2018, the expense was $19 million Canadian dollars.
“Plavix was one of the most commonly used drugs in cardiology,” Dr Ko said, “so switching to generics can reduce a lot of cost for individuals and health systems.”