Key clinical point: Pretreatment calprotectin (MRP8/14) levels demonstrated no additional variability in predicting treatment response to tumor necrosis factor inhibitors (TNFis) beyond that of C-reactive protein (CRP) levels alone in patients with rheumatoid arthritis (RA).
Major finding: Higher vs lower pretreatment CRP levels predicted a good/moderate European League Against Rheumatism response at 3 months (odds ratio 3.79; P < .001), but MRP8/14 levels along with CRP levels offered no significant predictive improvement ( P = .62). Unlike CRP level alone, pretreatment MRP8/14 level alone did not predict response to TNFi, as determined by Clinical Disease Activity Index ( P = .839).
Study details: This post hoc analysis included 470 patients with RA whose serum MRP8/14 levels were measured before initiating adalimumab (n = 196) or etanercept (n = 274) treatment and after 3 months of adalimumab treatment (n = 179).
Disclosures: This study was supported by the UK National Institute for Health Research (NIHR) and other sources. Two authors declared being NIHR Senior investigators. Several authors reported ties with various sources unrelated to this study.
Source: Smith SL et al. Pre-treatment calprotectin (MRP8/14) provides no added value to testing CRP alone in terms of predicting response to TNF inhibitors in rheumatoid arthritis in a post hoc analysis. Ann Rheum Dis . 2023 (Feb 21). Doi: 10.1136/ard-2022-222519