A report of three multiclinic trials evaluating arbaprostil in arthritic patients with ASA/NSAID gastric mucosal damage

Three randomized, placebo-controlled multiclinic trials involving arbaprostil dosages of (a) 10 μg; (b) 25 μg; and (c) 10, 25, or 50 μg orally for 4 wk in patients older than 18 yr with rheumatoid arthritis or osteoarthritis who had endoscopically documented nonsteroidal antiinflammatory drug-associated gastric mucosal damage were conducted in the United States. All patients continued taking the nonsteroidal antiinflammatory drugs and were reendoscoped after 4 wk of therapy. Success at that time was defined as complete resolution of all gastric mucosal damage. Six hundred fifty-eight patients were enrolled in the three trials. Significantly more patients experienced healing in the arbaprostil treatment groups in all trials compared with those who received placebo. The healing rates in the various trials were 68% and 32% (10 μg vs. placebo; p = 0.007); 77% and 23% (25 μ g vs. placebo; p < 0.001); and 52%, 46%, 35%, and 16% (50, 25, and 10 μg vs. placebo; p < 0.001, <0.001, and 0.002, respectively). Diarrhea, mostly of a mild nature, was the only arbaprostil-associated side effect and was found with the 25- and 50-μg dosages (33% and 59%, respectively). No exacerbation of arthritis signs or symptoms was found. Arbaprostil at doses with varying effects on gastric acid secretion (25 and 50 μ]g) was documented in these trials to be an effective and safe agent for healing gastric mucosal damage associated with aspirin or other nonsteroidal antiinflammatory drugs in patients with either rheumatoid arthritis or osteoarthritis without adversely affecting joint symptomatology.