Selective inhibitors of cyclo-oxygenase-2 (COX-2) appear to be safer than conventional NSAIDs on the gastrointestinal (GI) tract. Amtolmetin guacyl (AMG), a NSAID that inhibits both COX-1 and COX-2, has an anti-inflammatory effect comparable to that of traditional NSAIDs, with a better GI safety profile. The primary end-point of this study was to evaluate the gastrointestinal safety of amtolmetin guacyl in comparison with celecoxib in patients affected with rheumatoid arthritis. The assessment of efficacy was the secondary end-point.
This study was a 24-week, randomized, parallel group, double-blind, double dummy, multicentre trial; 235 patients were enrolled and 180 patients (85 in the AMG group and 95 in the celecoxib group) completed the study. Each patient received twice daily amtolmetin guacyl 600 mg or celecoxib 200 mg. Assessment of safety was performed by upper GI endoscopy, gastrointestinal symptoms evaluation, electrocardiography, blood and urine laboratory tests, adverse events recording. Assessment of efficacy was performed by using the American College of Rheumatology (ACR-20) responder index.
Neither amtolmetin guacyl nor celecoxib determined a worsening of baseline gastro-duodenal endoscopy findings. The percentage of patients with normal findings did not significantly change after treatment with both drugs, being virtually identical with AMG (i.e. 75.29%) and increasing from 75.79% to 77.66% with celecoxib. Moreover an evaluation of the other safety parameters did not reveal any difference between the two treatment groups. Therapeutic efficacy was equivalent in both groups, with no statistical difference between the two drugs at all time intervals.
In patients affected with rheumatoid arthritis, AMG and celecoxib proved to be equivalent, showing comparable gastrointestinal safety and therapeutic efficacy of treatment.