Hypersensitivity cases associated with drug-eluting coronary stents: a review of available cases from the Research on Adverse Drug Events and Reports (RADAR) project.
OBJECTIVE
We undertook the review of all available cases of hypersensitivity reactions after placement of a drug-eluting stent (DES) and classified potential causes.


BACKGROUND
Six months after the approval of the first DES, the Food and Drug Administration (FDA) reported 50 hypersensitivity reactions after stent placement but later concluded these were due to concomitantly prescribed medications such as clopidogrel. Nevertheless, the FDA continued to receive reports of hypersensitivity.


METHODS
Reports available from April 2003 through December 2004 for hypersensitivity-like reactions associated with the sirolimus-eluting stent (CYPHER, Cordis Corp., Miami Lakes, Florida) and paclitaxel-eluting stent (TAXUS, Boston Scientific Corp., Natick, Massachusetts) were reviewed. Sources of reports included the FDA's adverse-device-event database, the published literature, and investigators from the Research on Adverse Drug/Device events And Reports (RADAR) project. Causality was assessed using standardized World Health Organization criteria.


RESULTS
Of 5,783 reports identified for the DES in the FDA database, 262 unique events included hypersensitivity symptoms. Of these reports, 2 were certainly and 39 unlikely caused by clopidogrel and 1 was certainly, 9 probably, and 13 unlikely caused by the DES. From all sources, we identified 17 distinct cases that were probably or certainly caused by the stent, of which 9 had symptoms that lasted longer than four weeks. Four autopsies confirmed intrastent eosinophilic inflammation, thrombosis, and lack of intimal healing.


CONCLUSIONS
The FDA reports and autopsy findings suggest that DES may be a cause of systemic and intrastent hypersensitivity reactions that, in some cases, have been associated with late thrombosis and death.
Nebeker
Jonathan R
JR
Veterans Administration Salt Lake City, Salt Lake City, Utah, USA. Jonathan.Nebeker@hsc.utah.edu
Virmani
Renu
R
Bennett
Charles L
CL
Hoffman
Jennifer M
JM
Samore
Matthew H
MH
Alvarez
Jorge
J
Davidson
Charles J
CJ
McKoy
June M
JM
Raisch
Dennis W
DW
Whisenant
Brian K
BK
Yarnold
Paul R
PR
Belknap
Steven M
SM
West
Dennis P
DP
Gage
Jonathan E
JE
Morse
Richard E
RE
Gligoric
Gordana
G
Davidson
Laura
L
Feldman
Marc D
MD
D003331:Coronary Vessels; D004342:Drug Hypersensitivity / Q000209:etiology*; D006801:Humans; D017239:Paclitaxel / Q000009:adverse effects*; D020123:Sirolimus / Q000009:adverse effects*; D015607:Stents / Q000009:adverse effects*
D017239:Paclitaxel; D020123:Sirolimus