Spontaneous Reports

SPONTANEOUS REPORTS

The spontaneous adverse drug reaction reporting system is usually the first line of defense in the detec-tion of adverse drug effects that may not be apparent during pre-marketing studies, but the cardiovascular safety signal for rofecoxib was not detected by the Adverse Event Reporting System in the US. After the VIGOR results were reported in professional meet-ings in May 2000, the Netherlands Pharmacovigi-lance Center (Lareb) reported a cardiovascular safety signal for rofecoxib at the annual meeting of National Centers that participated in the WHO Programme for International Drug Monitoring in October 2000 (Edwards, 2005), but that report was not widely known in the US.

In the US, Mukherjee and colleagues conducted a search for thrombotic or embolic events associated with celecoxib and rofecoxib in the US Adverse Event Reporting System in October 2000 (Mukherjee, 2001).

The number of cases that could possibly be associ-ated with celecoxib and rofecoxib were 99 and 102 respectively. Of the 99 patients who used rofecoxib, there were 26 cases of myocardial infarction, 43 cases of stroke, 19 cases of pulmonary embolism or venous thrombosis, and 14 cases of miscellaneous thrombotic events. Given the millions of doses of rofecoxib and celecoxib that had been dispensed in the US by then, the small number of reported adverse cardiovascular events did not represent a strong numeric signal.

Aside from the spontaneous reporting system, there was no case report in clinical journals on a suspected association between rofecoxib and myocardial infarc-tion. A simple PUBMED search by one of the authors (KAC) in December 2005 using the search term ‘rofecoxib case reports’ identified 119 publi-cations, which included case reports of hepatitis, interstitial nephritis, colitis, angioedema, anaphylac-tic shock, gynecomastia, acute renal failure, delirium, Stevens–Johnson syndrome, congestive heart failure, and transient visual impairment and potential drug– drug interactions in MEDLINE-indexed journals. Not a single case of myocardial infarction was reported in these peer-reviewed journals.