A comparison of renal-related adverse drug reactions between rofecoxib and celecoxib, based on the World Health Organization Uppsala Monitoring Centre safety database

Background: Two isoforms of cyclooxygenase (COX) have been identified, both of them inhibited by traditional nonsteroidal anti-inflammatory drugs (NSAIDs). Inhibition of COX-2 has been associated with the therapeutic effects of NSAIDs, whereas inhibition of COX-1 is believed to be the cause of the adverse gastrointestinal effects associated with NSAID therapy. When administered at therapeutic doses, new COX-2-specific inhibitors inhibit only the COX-2 isoform. Objective: This study sought to compare renal safety signals between the COX-2-specific inhibitors rofecoxib and celecoxib, based on spontaneous reports of adverse drug reactions (ADRs) in the World Health Organization/Uppsala Monitoring Centre (WHO/UMC) safety database through the end of the second quarter 2000. Methods: Disproportionality in the association between a particular drug and renal-related ADR was evaluated using a bayesian confidence propagation neural network method in which a statistical parameter, the information component (IC) value, was calculated for each drug-ADR combination. In this method, an IC value significantly greater than 0 implies that the association of a drug-ADR pair is stronger than background; the higher the IC value, the more the combination stands out from the background. The ratio of actual to expected numbers of ADRs was also used to assess disproportionality. Results: As with traditional NSAIDs, both COX-2-specific inhibitors were associated with renal-related ADRs. However, the adverse renal impact of rofecoxib was significantly greater than that of celecoxib. IC values were significantly different for the following comparisons: water retention (1.97 rofecoxib vs 1.18 celecoxib; P<0.01); abnormal renal function (2.38 vs 0.70; P<0.01); renal failure (2.22 vs 1.09; P<0.01); cardiac failure (2.39 vs 0.48; P<0.01); and hypertension (2.15 vs 1.33; P<0.01). In an additional analysis, celecoxib was shown to have a similar renal safety profile to that of diclofenac and ibuprofen. Conclusions: Based on spontaneous ADR reports in the WHO/UMC safety database at the end of the second quarter 2000, this analysis indicates that rofecoxib has significantly greater renal toxicity than celecoxib or traditional NSAIDs. This negative renal impact may have the potential to increase the risk for serious cardiac and/or cerebrovascular events.