The COX-2-specific inhibitor parecoxib sodium is opioid-sparing and improves pain relief as part of a multimodal treatment strategy

Background

Opioid analgesics, although effective in managing acute postoperative pain, are associated with side effects, which can limit pain control and can delay recovery. Thus, multimodal (combination) analgesia is often utilized to reduce opioid use and improve pain relief. The opioid-sparing effects and analgesic efficacy of parecoxib sodium (parecoxib), a novel injectable COX-2-specific inhibitor, were evaluated in two postsurgical pain models.

Methods

In two multicenter, double-blind, randomized, placebo-controlled studies, patients who had undergone either hip or knee replacement received morphine by patient-controlled analgesia (PCA) plus either parecoxib 20 mg IV every 12 hours, parecoxib 40 mg IV every 12 hours, or placebo. The total cumulative amount of morphine used, pain intensity difference, pain relief, and Patient's Global Evaluation of Study Medication were assessed.

Results

Parecoxib demonstrated significant opioid-sparing effects in both surgical models. In the first 24 hours following surgery, patients receiving parecoxib 20 mg and 40 mg used 16–22% and 28–39% less morphine, respectively, than patients receiving placebo. The effects of parecoxib on morphine consumption were dose dependent and statistically significant. Despite this reduction in morphine use, parecoxib-treated patients experienced significantly improved pain relief and significant reductions in pain intensity compared with patients receiving morphine alone. For example, in the hip replacement model, 85.2% and 81.8% of patients in the parecoxib 20 mg and 40 mg treatment groups were categorized as having 'a lot' or 'complete' pain relief compared with 61.9% of patients receiving morphine alone (P < 0.05). Consistent with these findings, in both studies parecoxib-treated patients reported a significantly better level of satisfaction with their medication than those receiving morphine plus placebo. Parecoxib also demonstrated significant reductions in some adverse events (fever and vomiting) in the hip replacement model.

Conclusions

Parecoxib in combination with morphine provides significant opioid-sparing effects, and improved pain management and patient satisfaction, in two major surgical pain models, compared with morphine alone.