Gastrointestinal safety and efficacy of long-term GCSB-5 use in patients with osteoarthritis: A 24-week, multicenter study

Ethnopharmacology relevance A previous study indicated non-inferiority of GCSB-5 to celecoxib regarding efficacy and safety in treating OA; however, the gastrointestinal (GI) safety data was limited to 12 weeks. Accordingly, a longer term study with a larger number of patients was necessary to establish the GI safety of GCSB-5. Aim of study The primary goal was to determine the safety and efficacy of 24-week use of GCSB-5. The secondary goal was to compare the GI safety data of GCSB-5 with that of the previously reported Celecoxib Long-term Arthritis Safety Study (CLASS). Method This was a 24-week, multicenter, single-arm phase IV Study for the safety and efficacy of GCSB-5. A total of 761 patients were enrolled and 756 patients received at least one dose of GCSB-5. Among them, 629 patients (82.7%) completed the 24 week follow up. The primary goal was to determine the safety and efficacy of GCSB-5 for 24 weeks. The secondary goal was to compare the GI safety data of GCSB-5 with that of the previously reported Celecoxib Long-term Arthritis Safety Study (CLASS). Results The incidence of GI disorders of GCSB-5 was 23.7%. The annual rate of perforation, ulcer obstruction, or bleeding (PUB) incidence was 0.0%. The drop-out rate due to GI disorders following GCSB-5 use was 4.8%. Compared to celecoxib data from CLASS, the incidence of GI disorders (23.7% vs. 31.4%, p<0.001), annual rate of PUB and gastroduodenal ulcers (0.0% vs 2.2%, p=0.004), and drop-out rate due to GI disorders following GCSB-5 use were significantly low (4.8% vs 8.7%, p<0.001). Efficacy was proven by significant improvements in Western Ontario McMaster Questionnaire (WOMAC) scale, Korean Knee Score (KKS), 100-mm pain visual analogue scale (VAS), and physician's global assessments of patient's response to therapy (PGART). Conclusions The safety and efficacy profile of GCSB-5 are comparable to celecoxib. These results indicate GCSB-5 is safe for a long-term treatment of knee OA patients. Trial registration ClinicalTrials.gov (NCT01604239).