The gastrointestinal safety of the COX-2 selective inhibitor etoricoxib assessed by both endoscopy and analysis of upper gastrointestinal events

Abstract

Objectives: Etoricoxib is a selective cyclooxygenase inhibitor that in clinical studies has improved the signs and symptoms of osteoarthritis and rheumatoid arthritis and reduced the potential for GI injury. The incidence of endoscopically detected ulcers and of clinically important upper GI events (perforations, ulcers, and bleeding episodes) was compared in patients taking etoricoxib or nonselective nonsteroidal anti-inflammatory drugs (NSAIDs).

Methods: Upper GI endoscopy was performed at intervals over 12 wk in 680 patients taking etoricoxib 120 mg once daily, ibuprofen 800 mg three times daily, or placebo in a randomized, parallel-group, double-blind study. Survival analysis was used to analyze time-to-event data for the incidence of gastric or duodenal ulcers (> or =3 mm and > or =5 mm), and the log rank test was used to compare the cumulative incidence between treatment groups. A combined analysis of upper GI events in all 10 Phase II/III clinical trials of etoricoxib (60, 90, or 120 mg) versus nonselective NSAIDs (naproxen, ibuprofen, or diclofenac) for osteoarthritis, rheumatoid arthritis, and chronic low back pain was conducted. Investigators reported potential events for adjudication by an external, blinded committee, using prespecified criteria to confirm events. All events that occurred during active treatment periods (maximum 792 days) or within 14 days of stopping treatment were included in the analysis. Time to first event was evaluated using survival analysis; the Kaplan-Meier method was used to determine the cumulative incidence, and relative risk was estimated with the Cox proportional hazards model.

Results: In the endoscopy study, the cumulative incidence of ulcers >/=3 mm at 12 wk in the ibuprofen group (17%) was significantly higher than in the etoricoxib group (8.1%, p < 0.001); similar results were seen for ulcers >/=5 mm. In the placebo group, the rate of ulcers >/=3 mm was 1.86%. Of 3142 patients treated with once-daily etoricoxib and 1828 patients treated with a nonselective NSAID (ibuprofen, naproxen, or diclofenac), 82 patients with investigator-reported upper GI events (71 confirmed) were eligible for the combined analysis. For etoricoxib versus NSAIDs, the rate per 100 patient-yr for confirmed events was 1.16 versus 3.05 (relative risk = 0.44, 95% CI = 0.27-0.72, p < 0.001), whereas that for investigator-reported events was 1.35 versus 3.42 (relative risk = 0.47, 95% CI = 0.30-0.74, p = 0.001). Results were driven primarily by studies with naproxen as the comparator.

Conclusions: The incidence of endoscopically detected ulcers was significantly lower with etoricoxib 120 mg than with ibuprofen 2400 mg. Treatment with etoricoxib reduced the incidence of investigator-reported and confirmed adverse upper GI events by approximately 50% compared with treatment with nonselective NSAIDs.