RESEARCH - New drug treatments tested in fibromyalgia

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New drug treatments tested in fibromyalgia

Rheumawire

Nov 3, 2004

Janis

San , TX - Fibromyalgia (FM) treatment studies reported at the

American College of Rheumatology 2004 meeting showed that researchers

are attacking the problematic disease from several angles, deploying

existing drugs in new ways and taking a closer look at the efficacy of

several widely used treatments. The antidepressant duloxetine (Cymbalta,

Eli Lilly & Co) continues to look promising.

A research team led by Dr Joachim F Wernicke (Eli Lilly, Indianapolis,

IN) reported data [1] that extend and further support work reported

earlier this year [2]. Their 12-week, double-blind, randomized trial

showed that duloxetine at either 60 mg once daily (n=118) or 60 mg twice

daily (n=116) provided significantly better pain relief than placebo

(n=120, p<0.001). Subjects were female patients with fibromyalgia, and

the primary outcome measure was 24-hour pain severity score on the Brief

Pain Inventory (BPI). (Earlier work had suggested that there might be

less response to duloxetine in males with fibromyalgia, and they were

not included in this study.)

Response was defined as a 30% reduction in BPI 24-hour average pain

score. Significantly more duloxetine-treated patients had responses

compared with placebo (55% duloxetine 60 mg qd vs 33% placebo, p<0.001;

54% duloxetine 60 mg bid vs 33% placebo, p<0.002).

Although both duloxetine regimens were better than placebo, only

duloxetine 60 mg bid was associated with significant improvements in

mean tender-point threshold and in reduction in number of tender points

with low threshold. More duloxetine-treated patients reported adverse

events, but the rates of serious adverse events were not significantly

different from placebo (placebo 0%, duloxetine 60 mg qd 0.8%, duloxetine

60 mg bid 0.9%).

Dr Xavier J Caro (Northridge Hospital Medical Center, CA) reported that

intravenous immunoglobulin G (IVIg) might help a subset of FM patients

who appear to have chronic inflammatory demyelinating polyneuropathy

(CIDP) and should be studied further in this subset. This has clinical

implications for many FM patients, since nearly half of the FM patients

screened for this study had electrophysiologic evidence of demyelination

in 2 or more peripheral nerves, and 26% met the criteria for treatment

with IVIg [3].

Caro and colleagues reasoned that CIDP, which has been reported in a

subset of FM patients, is immune-mediated and known to respond to IVIg,

so they conducted an open-label trial of IVIg in patients from this

subset. They screened 49 of 58 consecutive FM patients for

electrodiagnostic evidence of demyelination. Of them, 23 patients had

signs of demyelination in 2 or more peripheral nerves, and 15 of these

23 met the eligibility criteria for IVIg treatment. " Eligibility

required an absence of another explanation for demyelination; normal

cardiovascular, renal, and hepatic status; detectable serum IgA;

vascular accessibility; and an ability to give informed consent, " Caro

said.

The investigators gave each of these 15 patients a single dose of

methylprednisolone 1 week before IVIg to lessen side effects and then

treated each with IVIg 2 g/kg over 5 days. No significant adverse

effects were seen, and IVIg treatment was associated with significant

improvements in pain, tenderness, and strength.

Dr P White (CFRI, London, ON) tested xylocaine IM tender-point

injections vs saline injections for FM. He reported that xylocaine was

not significantly better and that both types of injections appear to

reduce FM pain and headaches for up to 8 weeks [4].

" Although there was a trend toward improvement in the xylocaine vs

saline treatment group at 2 weeks and the difference in the reduction in

number of weekly headaches approached significance, there were no

statistically significant intergroup differences. However, there was at

least some degree in reduction in symptoms for every 1 of the 60

follow-up vs baseline comparisons, and 32 of those reductions achieved

statistical significance: 18 for saline, 14 for xylocaine, " White said.

Sources

Wernicke JF, Rosen AS, Lu Y, et al. Duloxetine in the

treatment of fibromyalgia. American College of Rheumatology 2004

meeting, San , TX, October16-21, 2004; Abstract 1867.

Arnold LM, Lu Y, Crofford LJ, et al. A double-blind,

multicenter trial comparing duloxetine with placebo in the treatment of

fibromyalgia patients with or without major depressive disorder.

Arthritis Rheum 2004; 50:2974-2984.

Caro XJ, Winter EF. A subset of fibromyalgia patients

with findings suggestive of chronic inflammatory demyelinating

polyneuropathy (CIDP) responds to intravenous immunoglobulin (IVIg).

American College of Rheumatology 2004 meeting; San , TX; October

16-21, 2004; Abstract 721.

White KP, Harth M, Speechley M, et al. The tender

point injection trial: a double-blind, randomized comparison of

xylocaine versus saline tender point injections in patients with

fibromyalgia (FM). American College of Rheumatology 2004 meeting; San

, TX; October 16-21, 2004; Abstract 732.

I'll tell you where to go!

Mayo Clinic in Rochester

http://www.mayoclinic.org/rochester

s Hopkins Medicine

http://www.hopkinsmedicine.org