UMMS Affiliation

Department of Medicine, Division of Rheumatology

Publication Date


Document Type



Immune System Diseases | Musculoskeletal Diseases | Rheumatology | Skin and Connective Tissue Diseases


INTRODUCTION: Anti-cyclic citrullinated peptide (anti-CCP) antibodies are associated with poor prognosis in patients with rheumatoid arthritis (RA). Previous data from randomized controlled trials and clinical practice have shown anti-CCP-positive (+) patients had a better response to treatment with abatacept or tumor necrosis factor inhibitor (TNFi) treatment than those who were anti-CCP negative. This study assessed the association between baseline anti-CCP2 [a surrogate for anti-citrullinated protein antibody (ACPA)] concentration and 6-month treatment responses to abatacept or TNFi in patients with RA.

METHODS: This real-world analysis included biologic-experienced patients from CERTAIN (Comparative Effectiveness Registry to study Therapies for Arthritis and Inflammatory CoNditions) who initiated abatacept or TNFi, had prior biologic disease-modifying drug exposure and baseline anti-CCP2 concentration/serostatus and serum samples (baseline and 6 months). Baseline demographics and disease characteristics were compared. Change from baseline at 6 months in Clinical Disease Activity Index (CDAI) score and patient-reported outcomes [PROs: pain, fatigue, patient global assessment (PtGA), modified Health Assessment Questionnaire (mHAQ) score], by baseline anti-CCP2 quartile and binary cut-off ( > 10-250 and > 250 U/ml), were evaluated separately in the abatacept and TNFi groups using a linear regression model adjusted for age, sex, CDAI/PROs, comorbidity index, and methotrexate use.

RESULTS: Included were 138 abatacept and 137 TNFi initiators who were anti-CCP2+. At baseline, there were significant differences between anti-CCP2 quartiles and mean CDAI, swollen joint count 28, C-reactive protein (CRP), Disease Activity Score 28 (CRP), rheumatoid factor (RF), mHAQ and physician global assessment among abatacept initiators, and in mean RF, mHAQ, and PtGA among TNFi initiators. Among abatacept (but not TNFi) initiators, CDAI numerically improved (p = 0.208) and PROs significantly improved (p < 0.05) with increasing baseline anti-CCP2.

CONCLUSIONS: In patients treated with abatacept, not TNFi, higher anti-CCP2 concentrations at baseline were associated with numerically greater improvements in CDAI and significant improvements in PROs after 6 months.



Abatacept, Patient-reported outcome measures, Rheumatoid arthritis, Tumor necrosis factor inhibitors

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Copyright © The Author(s) 2021. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, which permits any non-commercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit

DOI of Published Version



Harrold LR, Bryson J, Lehman T, Zhuo J, Gao S, Han X, Schrader A, Rebello S, Pappas DA, Sommers T, Kremer JM. Association Between Baseline Anti-cyclic Citrullinated Peptide Antibodies and 6-Month Clinical Response Following Abatacept or TNF Inhibitor Treatment: A Real-World Analysis of Biologic-Experienced Patients with RA. Rheumatol Ther. 2021 Jun;8(2):937-953. doi: 10.1007/s40744-021-00310-2. Epub 2021 May 28. PMID: 34047953; PMCID: PMC8217398. Link to article on publisher's site

Journal/Book/Conference Title

Rheumatology and therapy

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Creative Commons License

Creative Commons Attribution-Noncommercial 4.0 License
This work is licensed under a Creative Commons Attribution-Noncommercial 4.0 License