Combination drug containing high-dose enteric-coated aspirin, omeprazole may improve gastrointestinal safety relative to enteric-coated aspirin alone, study data indicate

The safety of an investigational combination drug containing 325 mg of enteric-coated aspirin and 20 mg of immediate-release omeprazole surpasses that of high-dose enteric-coated aspirin alone, according to data from 2 clinical trials. In light of the reduced cardioprotection provided by lower-dose aspirin as compared with higher doses, researchers conducted a single-blind, controlled trial in 80 healthy subjects with no endoscopic evidence of gastroduodenal mucosal damage who were...

The safety of an investigational combination drug containing 325 mg of enteric-coated aspirin and 20 mg of immediate-release omeprazole surpasses that of high-dose enteric-coated aspirin alone, according to data from 2 clinical trials.

In light of the reduced cardioprotection provided by lower-dose aspirin as compared with higher doses, researchers conducted a single-blind, controlled trial in 80 healthy subjects with no endoscopic evidence of gastroduodenal mucosal damage who were randomized to receive the combination drug (n=41) or 81 mg of enteric-coated aspirin (n=39) per day. The primary endpoint was gastroduodenal mucosal changes, as determined by the Lanza score, at day 28. A separate study compared gastroduodenal mucosal changes in patients treated daily with the combination drug (n=40) versus those who received 325 mg of enteric-coated aspirin (n=40).

Results of the first study indicated that the rate of gastric and duodenal Lanza 3 or 4 scores--which equates to more than 20 erosions/hemorrhages or ulcers--at 28 days among the patients who received the combination drug was 9.8% (n=4), compared with a rate of 20.5% (n=8) in the enteric-coated aspirin monotherapy group, although the between-group difference failed to reach statistical significance (P=.22).

However, in the second study, which featured the higher dose of enteric-coated aspirin monotherapy, the rates of gastric and duodenal Lanza 3 or 4 scores at 28 days significantly favored the combination drug (7.5% vs 47.5%; P<.001).

Additionally, in the first study, the patients who received the combination drug achieved a significantly greater reduction in urinary 11-dehydrothromboxane B2 concentration--a measure of platelet function--as compared with the patients who received enteric-coated aspirin monotherapy (mean percentage change from baseline, -75% vs -64%; P=.008).

"Compared to enteric-coated aspirin 81 mg, [the combination drug] produces superior inhibition of in vivo thromboxane generation," the authors of the study concluded. "[The combination drug] may provide an important option for all patients treated with aspirin."

The study's lead researcher, Dr. Paul Gurbel, noted that additional large-scale prospective studies are necessary to confirm the efficacy of the investigational drug.

These data were presented in New Orleans, Louisiana, at the American Heart Association's Scientific Sessions 2008.

This information concerns a use that has not been approved by the Food and Drug Administration.