Clinical performance of an infliximab rapid quantification assay
Fernando Magro1, Joana Afonso2, Susana Lopes3
1Department of Biomedicine, Unity of Pharmacology and Therapeutics, Faculty of Medicine, University of Porto, Porto, Portugal.
Therapeutic Advances in Gastroenterology
|September 22, 2017
Summary
A rapid infliximab (IFX) test offers a reliable alternative for monitoring ulcerative colitis patients. This quick assay, with a 3 µg/ml threshold, accurately assesses endoscopic remission and inflammatory burden.
Area of Science:
- Gastroenterology
- Pharmacology
- Clinical Chemistry
Background:
- Therapeutic drug monitoring (TDM) algorithms guide infliximab (IFX) adjustments in inflammatory bowel disease (IBD).
- Exploring a rapid IFX quantification test is crucial for clinical application.
Purpose of the Study:
- To evaluate a rapid IFX quantification assay for clinical use in IBD patients.
- To compare the rapid assay with a reference kit for IFX trough level measurement.
Main Methods:
- Prospective cohort study of 110 ulcerative colitis (UC) patients on maintenance IFX therapy.
- Quantification of IFX trough levels using a rapid assay and a reference kit.
Main Results:
- IFX trough levels differed significantly between patients with and without endoscopic remission and varied by fecal calprotectin (FC) levels.
- The rapid assay and reference kit showed good correlation (Spearman's rho = 0.843) but with a systematic variation (reference kit values higher by 2.62 units).
- A 3 µg/ml threshold was effective for assessing endoscopic status and inflammation using both assays, with 88% positive outcomes above this level.
Conclusions:
- The rapid IFX assessment system with a 3 µg/ml threshold is a viable alternative to time-consuming ELISAs for IFX monitoring in UC patients.
- This rapid assay facilitates timely clinical decisions for IFX dose adjustments in IBD management.
