ACR Meeting Abstracts

ACR Meeting Abstracts

  • Home
  • Meetings Archive
    • ACR Convergence 2020
    • 2020 ACR/ARP PRSYM
    • 2019 ACR/ARP Annual Meeting
    • 2018 ACR/ARHP Annual Meeting
    • 2017 ACR/ARHP Annual Meeting
    • 2017 ACR/ARHP PRSYM
    • 2016-2009 Meetings
    • Download Abstracts
  • Keyword Index
  • Advanced Search
  • Your Favorites
    • Favorites
    • Login
    • Register
    • View and print all favorites
    • Clear all your favorites
  • Meeting Resource Center

Abstract Number: 2508

Tocilizumab Serum Trough Levels and Its Relationship with Disease Activity and Drug Dosage in Rheumatoid Arthritis Patients

Virginia Ruiz-Esquide1, Azucena Gonzalez-Navarro2, Jordi Yagüe3, Jose Inciarte-Mundo1, M. Victoria Hernández1, Julio Ramirez1, Sonia Cabrera-Villalba1, Juan D. Cañete1 and Raimon Sanmarti1, 1Arthritis Unit. Rheumatology Department, Hospital Clínic of Barcelona, Barcelona, Spain, 2Immunology Department, Hospital Clinic of Barcelona, Barcelona, Spain, 3Immunology Department, Hospital Clinic Barcelona, Barcelona, Spain

Meeting: 2014 ACR/ARHP Annual Meeting

Keywords: C Reactive Protein, IL-6, rheumatoid arthritis (RA) and tocilizumab

  • Tweet
  • Email
  • Print
Save to PDF
Session Information

Session Title: Rheumatoid Arthritis - Small Molecules, Biologics and Gene Therapy: Therapeutic Strategies, Biomarkers and Predictors of Outcomes in Rheumatoid Arthritis

Session Type: Abstract Submissions (ACR)

Background/Purpose

Tocilizumab (TCZ) is a humanized monoclonal antibody against interleukin-6 receptor used for the treatment of active rheumatoid arthritis (RA). The response to this treatment may depend on the serum levels achieved, which depends on the interval and the total dose administered.

Purpose

To analyze TCZ serum trough levels and antidrug antibodies (ADA) in a cohort of RA patients in chronic treatment with TCZ; and to evaluate its relationship with disease activity, serum levels of IL6 and CRP and drug levels.

Methods

Cross-section study including all RA patients attended in our Arthritis Unit undergoing chronic treatment with TCZ. Analysis of demographic data, disease activity IL6 and CRP serum levels together with TCZ serum levels and ADA (LISA TRACKER Tocilizumab LTT005 DuoDrug + ADAb) was done. All drug levels were measured before treatment infusion. Drug levels were correlated with different clinical and serological parameters.

Results

33 RA patients were included (91% women, age 53 ±12 years, disease duration 15.3 ± 9.7 years, anti-CCP+ 66.7%, monotherapy 22.2%, DAS28 2.9 ± 1.1). No patient showed presence of ADA. In 14 patients (42%) serum levels of TCZ were non-detectable (<1 ug/ml). Patients with detectable levels of TCZ showed higher levels of IL6 and lower levels of CRP than those with non-detectable levels (Table). 15 patients received reduced dose of TCZ (4-6 mg/Kg) due to persistent remission or low disease activity. In these patients serum levels of TCZ were lower than in those with standard dose, without differences on disease activity or CRP between groups. A significant positive correlation was found between IL6 levels and TCZ serum levels (R2=0.268, p=0.005), but not with DAS28 or CRP. In 3 patients, all of them with low disease activity, a curve of TCZ serum levels was done by TCZ dosage at baseline (before drug infusion) and 10, 20 and 28 days thereafter. In two patients, TCZ serum levels were not detectable by day 20. The third patient showed adequate levels through the entire period.

Conclusion

In a clinical setting of RA patients in treatment with TCZ no ADA were found.  An important proportion of RA patients treated with TCZ had undetectable serum trough levels (42%), showing higher CRP levels, and lower IL-6, but no differences were found in disease activity measured by DAS28-ESR.


Distribution of patients according to TCZ serum trough levels

 

Non detectable drug levels

(< 1 ug/ml) n=14

Detectable drug levels

(> 1 ug/ml) n=19

p

Dose interval (days – mean)

31.9 ± 3

29.9 ± 3

0.323

Serum IL6 levels (ug/ml)

2.8 ± 2.3

7.8 ± 2

0.012

CRP (mg/dl)

1.1 ± 1.4

0.1 ± 0.3

0.001

Hemoglobin (g/dl)

13.5 ± 15

12.8 ± 12

0.214

Reduced dose of TCZ (%)

79%

42%

0.053

DAS28-ESR

3.1 ± 1

2.8 ± 1

0.499

Remission (DAS28-ESR<2.6) (%)

29%

37%

0.956


Disclosure:

V. Ruiz-Esquide,
None;

A. Gonzalez-Navarro,
None;

J. Yagüe,
None;

J. Inciarte-Mundo,
None;

M. V. Hernández,
None;

J. Ramirez,
None;

S. Cabrera-Villalba,
None;

J. D. Cañete,
None;

R. Sanmarti,
None.

  • Tweet
  • Email
  • Print
Save to PDF

« Back to 2014 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/tocilizumab-serum-trough-levels-and-its-relationship-with-disease-activity-and-drug-dosage-in-rheumatoid-arthritis-patients/

Advanced Search

Your Favorites

You can save and print a list of your favorite abstracts by clicking the “Favorite” button at the bottom of any abstract. View your favorites »

ACR Convergence: Where Rheumatology Meets. All Virtual. November 5-9.

ACR Pediatric Rheumatology Symposium 2020

© COPYRIGHT 2021 AMERICAN COLLEGE OF RHEUMATOLOGY

Wiley

  • Home
  • Meetings Archive
  • Advanced Search
  • Meeting Resource Center
  • Online Journal
  • Privacy Policy
  • Permissions Policies
loading Cancel
Post was not sent - check your email addresses!
Email check failed, please try again
Sorry, your blog cannot share posts by email.
This site uses cookies: Find out more.