Background A previous study on GCSB-5 showed non-inferiority to Celecoxib in efficacy and safety in treating osteoarthritis, but its safety information on the gastrointestinal (GI) safety was limited to only 12 weeks. A longer term (24 weeks) study with a larger number of patients is necessary to establish the GI safety of GCSB-5.
Objectives The primary goal of this study was to determine the incidence of GI disorders associated with GCSB-5. The secondary goal was to collect the GI safety data of GCSB-5 and compare them with the safety data of the previously reported Celecoxib Long-term Arthritis Safety Study (CLASS).
Methods A single arm safety study of 24-week GCSB-5 for osteoarthritis patients was conducted. Then, the results of GI safety in this study were compared with those from the CLASS. This study was performed in 19 academic institutions between May 2012 and June 2013. Two GCSB-5 capsules (300 mg per capsule) were prescribed two times per day for 24 weeks. A total of 761 patients with osteoarthritis were enrolled and 756 patients took at least one dose of study drug. A total of 629 patients (82.7%) completed the 24 weeks follow-up visit. Incidence of GI disorders was the primary outcome. Incidence of GI perforation, ulcer obstruction and bleeding (PUB), and dropout due to GI complications were the major secondary outcome variables. All the suspected PUB events were forwarded to the GI event committee (GEC), consisted of GI specialist independent of investigators, for PUB diagnosis, treatment and related tests.
Results The incidence of GI disorders was 23.7%. Concomitant Aspirin use did not show any significant difference in GI disorders in this study cohort. The annualized incidence rate of PUB was 0.0%. The drop-out rate due to GI disorders in GCSB-5 was 4.8%. In comparison with CLASS, GCSB-5 was significantly lower in the incidence of GI disorders (23.7% vs 31.4%, p<0.001), annualized rate of PUB and gastroduodenal ulcer (0.0% vs 2.2%, p=0.004), and drop-out rate (4.8% vs 8.7%, p<0.001) due to GI disorders.
Conclusions This study indicated GCSB-5 was safe for osteoarthritis patients during long-term treatment. Furthermore, the safety results of GCSB-5 associated with GI disorder were comparable to Celecoxib.
Acknowledgements This study was supported by Green Cross Corporation, South Korea.
Disclosure of Interest None declared