SAN DIEGO, CA— At the 2013 ACR/ARHP Annual Meeting, study researchers presented that the investigational, lower-dose diclofenac submicron particle capsules were generally well-tolerated in patients with osteoarthritis (OA).
Nonsteroidal anti-inflammatory drugs (NSAIDs) are associated with dose-related gastrointestinal, cardiovascular, and renal adverse events. The FDA has recommended prescribing NSAIDs at “the lowest effective dose for the shortest duration consistent with individual patient treatment goals.”
The new submicron particle NSAIDs have enhanced absorption and may be efficacious at lower doses than commercially available NSAIDs. Clarence Young, MD, of Iroko Pharmaceuticals, Philadelphia, PA, and colleagues presented safety data from a Phase 3, randomized, multicenter, double-blind, parallel-group study. The study enrolled 305 patients ages 41–90 years old with OA of the hip or knee. Enrolled patients were chronic NSAID and/or acetaminophen users with a WOMAC pain subscore >40mm/100mm at baseline and a documented OA pain “flare” following NSAID discontinuation.
Patients were randomized to either diclofenac submicron particle capsules 35mg three times daily, 35mg twice daily, or placebo. The primary endpoint was mean change from baseline in WOMAC pain subscore at Week 12.
Diclofenac submicron particle capsules 35mg three times daily provided significantly better pain relief vs. placebo (P=0.0024) with numerical evidence of pain relief in the diclofenac submicron particle capsules 35mg twice daily treatment group– although this did not achieve statistical significance (P=0.0795).
No serious gastrointestinal bleeds or cardiovascular or renal adverse events occurred in any treatment group. The most frequent adverse events in patients who withdrew from the study (≥2% in any group) included diarrhea (4/305, 1.3%), upper abdominal pain (3/305, 1.0%), nausea (3/305, 1.0%), alanine aminotransferase elevation (2/305, 0.7%), and other abnormal liver function tests (2/305, 0.7%).
Dr. Young concluded, “No serious gastrointestinal bleeds or cardiovascular or renal adverse events occurred over 12 weeks of treatment. These results add to the emerging safety profile of investigational, lower-dose diclofenac submicron particle capsules.”