"Duloxetine (Cymbalta) Effective for Women With Fibromyalgia, With or Without Comorbid Depression"
By Bruce Sylvester
ATLANTA, GA -- May 30, 2005 -- The serotonin norepinephrine reuptake inhibitor (SNRI) antidepressant duloxetine (Cymbalta) has shown efficacy and safety for the treatment of women with fibromyalgia, whether or not they have major depression.
Study co-designer Joel Raskin, MD, medical advisor with the Cymbalta (duloxetine) team at Eli Lily and Company, Indianapolis, Indiana, United States, presented the findings here on May 26[th at the 158th Annual Meeting of the American Psychiatric Association (APA).
"Duloxetine showed a direct effect of 75% to 85% improvement in pain reduction," Dr. Raskin said. "Sixty milligrams a day was the effective dose, and that is similar to what we have seen with duloxetine for peripheral neuropathic diabetic pain."
"Very notably, duloxetine showed an effect on relief of the 'tender point' pain of fibromyalgia, which is one of the diagnostic criteria for the condition," Dr Raskin continued. "It is a truly objective finding among studies in which findings are often rather subjective. Here you see changes in a standard and objective measure of pain. This is really quite a unique finding."
The double-blind study enrolled women with fibromyalgia with or without depression to 12 weeks of treatment followed by 1 week off treatment. The researchers randomized 118 women to duloxetine 60 mg once daily, 116 women to 60 mg twice daily of duloxetine, and 120 women to placebo.
The primary outcome of the study was 24-hour average pain severity score using the Brief Pain Inventory (BPI).
The investigators defined "response to treatment" as a 30% reduction in the BPI 24-hour average pain score. Secondary outcomes included scores for remaining BPI pain and interference scores, Fibromyalgia Impact Questionnaire (FIQ), the tender point pain threshold and tender point number, Clinical Global Impression of Severity (CGI-Severity), Patient Global Impression of Improvement (PGI- Improvement), and 17-item Hamilton Rating Scale for Depression. They also assessed health outcome measures.
Results show a significant difference between duloxetine and placebo in BPI 24-hour average pain scores. Treatment effects of both doses of duloxetine on significant pain did not depend on its effect on mood or on a baseline diagnosis of major depression.
Duloxetine 60 mg twice daily showed superiority over placebo in improving mean tender point threshold (P = .003) and reducing the number of tender points with low threshold (P = .046).
Both doses of duloxetine resulted in significantly improved scores on CGI-Severity (P = .005) and PGI-Improvement (P < .006) compared to placebo. Compared to placebo, both doses of duloxetine resulted in significantly improved scores on other secondary measures (BPI 24-hour average pain area under the curve, FIQ total score, all other BPI pain and interference scores).
There were no significant efficacy differences between duloxetine dosings.
Significantly more duloxetine-treated patients reported treatment-emergent adverse events (placebo 79.2%, duloxetine 60 mg once-daily 92.4%, duloxetine 60 mg twice daily 90.5%). However, rates of serious adverse events in both duloxetine treatment groups did not differ significantly from placebo (0%, 0.8%, 0.9%, respectively).
"Both doses of duloxetine were numerically superior to placebo on most health outcome measures," the authors noted.
[Presentation title: Duloxetine in the Treatment of Fibromyalgia. Abstract NR860]
|
