Reduction of TNF-Alpha by Infliximab Does Not Predict Treatment Response

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Reduction of TNF-Alpha by Infliximab Does Not Predict Treatment Response

J Rheumatol 2007;34:2158-2161.

http://www.medscape.com/viewarticle/567998?src=mp

By Will Boggs, MD

NEW YORK (Reuters Health) - Reduction of elevated tumor necrosis factor

(TNF)-alpha levels after infliximab treatment does not predict treatment

response in patients with rheumatoid arthritis (RA), according to a report

in the November issue of The Journal of Rheumatology.

" Because of heterogeneity of RA, modern markers are needed in order to

better select patients for treatment, " Dr. Pierre Miossec from Hopital

Edouard Herriot, Lyon, France told Reuters Health. " It shows that the RA

story cannot be simplified as a TNF disease. "

Dr. Miossec and colleagues measured expression of TNF-alpha mRNA in

peripheral blood of 44 RA patients undergoing treatment in order to test its

predictive value for treatment response.

Constitutive TNF-alpha mRNA expression was significantly higher in RA

patients before infliximab treatment than in healthy controls, the authors

report, and mRNA levels remained significantly increased in patients at week

22 before the 5th infliximab infusion.

There was a trend toward a decrease in TNF-alpha mRNA expression over time,

especially in patients with high baseline TNF-alpha mRNA expression.

Except for patients with high baseline TNF-alpha mRNA expression, there were

no significant changes in mRNA expression 4 hours after the infliximab

infusion, the investigators say, and there were no significant differences

when the RA patients were stratified into responders and nonresponders.

" Neither TNF-alpha mRNA expression at baseline nor the magnitude of

infliximab-induced TNF-alpha mRNA variation was associated to treatment

response, " the authors conclude. " This suggests the major contribution of

anti-TNF-induced changes at other sites, mainly the synovium. "