Etanercept concentration in patients with rheumatoid arthritis and its potential influence on treatment decisions: a pilot study.

Abstract

OBJECTIVE:

For patients with rheumatoid arthritis (RA), recommendations are inconclusive about whether tumor necrosis factor-α (TNF-α)-blocker therapy should be evaluated at 3 or 6 months. Biomarkers are needed to predict at 3 months which patients would benefit from further treatment because of nonoptimal response. Our objective was to investigate whether serum etanercept (ETN) concentrations and anti-ETN antibodies at 3 months are predictors of clinical response to ETN at 6 months in patients with RA in terms of European League Against Rheumatism criteria and Disease Activity Score in 28 joints (DAS28).

METHODS:

Between 2009 and 2010, we included 19 women with active RA who were candidates for ETN therapy. Response criteria were evaluated at 3 and 6 months. Serum concentrations of ETN and anti-ETN antibodies were measured by ELISA at baseline and at 3 and 6 months.

RESULTS:

Eighteen patients completed followup. Three-month ETN concentrations were lower for 6-month nonresponders than responders (p = 0.03). Three-month ETN levels correlated significantly with change in DAS28 between baseline and 6 months (r = -0.62, p = 0.006). The best predictor of response at 6 months was observed with an ETN threshold of 3.1 μg/ml at 3 months. No anti-ETN antibodies were found.

CONCLUSION:

ETN concentrations at 3 months predict response to ETN therapy at 6 months. Low ETN concentrations could explain the absence of response to ETN, suggesting that patients with low ETN levels could benefit from increased ETN dose or earlier interruption of treatment.

• Authors: Claire Immediato Daïen, Vincent Daïen, Ermis Parussini, Anne-Marie Dupuy, Bernard Combe, Jacques Morel
• Journal: The Journal of rheumatology (J Rheumatol) Vol. 39 Issue 8 Pg. 1533-8 (Aug 2012) ISSN: 0315-162X [Print] Canada
• PMID: 22753654 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Antirheumatic Agents
• Immunoglobulin G
• Receptors, Tumor Necrosis Factor
• Etanercept

Topics

• Adult
• Aged
• Antirheumatic Agents (blood, therapeutic use)
• Arthritis, Rheumatoid (blood, drug therapy)
• Etanercept
• Female
• Humans
• Immunoglobulin G (blood, therapeutic use)
• Middle Aged
• Pilot Projects
• Predictive Value of Tests
• Receptors, Tumor Necrosis Factor (blood, therapeutic use)
• Severity of Illness Index
• Treatment Outcome