TOPLINE:
In patients with rheumatoid arthritis, the presence of antidrug antibodies was associated with a diminished response to biologic disease-modifying antirheumatic drugs in a prospective cohort study.
METHODOLOGY:
- Researchers prospectively analyzed data from 230 patients (mean age, 54.3 years; 77.0% women) with RA diagnosis recruited from March 3, 2014, to June 21, 2016.
- All were initiating new treatment with an anti–tumor necrosis factor (TNF) monoclonal antibody (mAb; either infliximab or adalimumab), etanercept, tocilizumab, or rituximab, according to the choice of the treating physician.
- The primary outcome was the association of antidrug antibody positivity with European Alliance of Associations for Rheumatology (EULAR) response to treatment at month 12, assessed through univariate logistic regression.
TAKEAWAY:
- At month 12, antidrug antibody positivity was 38.2% in patients who were treated with anti-TNF mAbs, 6.1% with etanercept, 50.0% with rituximab, and 20.0% with tocilizumab.
- There was an inverse association between antidrug antibody positivity directed against all biologic drugs and EULAR response at month 12 (odds ratio, 0.19; 95% confidence interval, 0.09-0.38; P < .001).
- In the multivariable analysis, antidrug antibodies, body mass index, and rheumatoid factor were independently and inversely associated with response to treatment.
- There was a significantly higher drug concentration of anti-TNF mAbs in patients with antidrug antibody–negative vs. antidrug antibody–positive status (mean difference, –9.6 mg/L; 95% CI, –12.4 to –6.9; P < .001).
IN PRACTICE:
Findings of this study suggest that antidrug antibodies are associated with nonresponse to biologic drugs and can be monitored in the management of patients with RA, particularly nonresponders.
SOURCE:
Samuel Bitouin, MD, PhD, of the rheumatology department at Paris-Saclay University, and coauthors in the ABIRISK (Anti-Biopharmaceutical Immunization: Prediction and Analysis of Clinical Relevance to Minimize the Risk) consortium reported the study in JAMA Network Open. The work was funded by a grant from the European Union Innovative Medicines Initiative.
LIMITATIONS:
Though the study demonstrated an association when all biologic drugs were analyzed together, it was not powered to demonstrate an association for each drug class.
DISCLOSURES:
Many authors reported financial relationships with pharmaceutical companies.
A version of this article first appeared on Medscape.com.