No Beneficial Effect Seen With Etoricoxib in Fibromyalgia

Fibromyalgia (FM) is a chronic pain disorder characterized by widespread musculoskeletal pain often accompanied by psychiatric pathology and cognitive dysfunction.  It is the most common cause of generalized musculoskeletal pain in women between the ages of 20 and 55 years in the United States, with a prevalence of approximately 2% to 3%.¹

Patients with FM generally respond most optimally to a multidisciplinary, individualized treatment program that incorporates healthcare providers across a number of specialties including pain medicine and rehabilitation, as well as mental health. Treatment of FM is directed at reducing the major symptoms of this disorder, including chronic widespread pain, fatigue, insomnia, and cognitive dysfunction. 

In a randomized, double-blinded study published in the International Journal of Clinical Practice, Mahagna and colleagues reported on the safety and efficacy of adding the cyclooxygenase-2 (COX-2)-selective inhibitor etoricoxib to the current therapeutic regimen in female patients with FM.² Participants were randomly assigned to 90 mg of etoricoxib once daily or placebo for 6 weeks. The primary outcome was response to treatment, which was defined as a >30% reduction in the Brief Pain Inventory Score. Secondary outcome measures were changes in the Fibromyalgia Impact Questionnaire, the SF-36 Quality of Life Assessment, and the Hamilton rating scales for anxiety and depression.

The researchers found no observed differences between patients receiving etoricoxib vs placebo on the reported assessment tools and concluded that the addition of etoricoxib to existing FM management regimens did not lead to any beneficial mental or physical effects. 

Summary and Clinical Applicability

Fibromyalgia is a widespread condition, affecting up to 2% of the population, with debilitating effects on activities of daily living and quality of life. Treatment of fibromyalgia is directed at reducing the major symptoms of this disorder, including chronic widespread pain, fatigue, insomnia, and cognitive dysfunction. Oftentimes multiple medication regimens are necessary to control pain symptoms in patients with FM.  This study showed that there was no measurable utility in adding the COX-2-selective inhibitor etoricoxib to existing pain management regimens in patients with FM.  Other pharmacologic and nonpharmacologic treatments should be considered if a patient necessitates further intervention.

References

1. Mahagna H, Amital D, Amital H.  A randomised, double-blinded study comparing giving etoricoxib vs. placebo to female patients with fibromyalgia. Int J Clin Pract. 2016; Jan 13. doi: 10.1111/ijcp.12760. [Epub ahead of print]

2. Schmidt-Wilcke T, Clauw DJ. Fibromyalgia: from pathophysiology to therapy. Nat Rev Rheumatol. 2011;7:518-527.