Background Currently, disease activity in Rheumatoid Arthritis (RA) is measured using scoring systems that rely primarily on a collection of subjective measures from patients and clinicians. To improve care and treatment for RA patients, objective measurements of disease activity and response to treatment are desirable. Using a small cohort derived from an ongoing study of intravenously administered golimumab (GO-FURTHER), we evaluated the performance of Vectra-DA™ (Crescendo Biosciences), a multi-biomarker serum-based test designed to measure RA disease activity through correlation with DAS28-CRP and is sensitive to anti-TNF therapy¹.

Objectives This analysis examines if Vectra-DA™ correlates with disease activity and golimumab response in a clinical trial setting.

Methods 137 serum samples collected in a Phase III study of intravenously administered golimumab in pts with active RA despite methotrexate (MTX) therapy were analyzed using Vectra-DA™ (Crescendo Bioscience^©; San Francisco, CA, USA). Samples were collected at wks 0, 2, 4, and 14 from patients (pts) treated with IV placebo + MTX (PBO; n= 42) or IV golimumab 2mg/kg + MTX (GLM; n=95) who received study medications at wks 0, 4, and every 8 weeks thereafter. Healthy control serum samples (n=21) were obtained from Bioreclamation (Hicksville, NY).

Results A subset of pts from the GO-FURTHER study was chosen for analysis with Vectra-DA™. Among pts in the GO-FURTHER subset, the ACR50 response rates were 35.8% for GLM and 7.1% for PBO at week 14 and 48.4% for GLM and 16.7% for PBO at wk 24. Correlation of Vectra-DA™ and DAS28-CRP scores was r=0.51 (95% CI=0.45-0.57) using all four timepoints tested. Study pts had statistically higher mean Vectra-DA™ scores (64.2 at wk 0; 45.5 at wk 2; 50.2 at wk4; 44.9 at wk14) compared to healthy controls (35.2). At baseline, there were no significant differences in GLM and PBO-treated pts by Vectra-DA™ or DAS28-CRP scores. As early as week 2, GLM-treated subjects had a significant drop in Vectra-DA™ score of ∆= -18.7 (p=<2.2X10-¹⁶). The decrease in Vectra-DA™ score was maintained through wk 14, whereas PBO-treated subjects did not have a significant change in Vectra-DA™ scores from baseline to weeks 2, 4 and 14. Vectra-DA™ scores were statistically different between GLM-treated pts who achieved ACR50 at wk 14 versus nonresponders at wks 0 (p=0.024), 4 (p=0.013), and 14 (p=0.009). Vectra-DA™ scores were not statistically different between GLM-treated pts who achieved an ACR50 response at wk 24 versus nonresponders at all timepoints tested, although a trend was seen at wk 14 (p= 0.054).

Conclusions Vectra-DA™ offers a molecular measurement of RA disease activity that can discriminate between normal subjects and RA pts, and also PBO and GLM-treated pts as early as wk 2 post-treatment. GLM treated wk14 responders had significantly lower Vectra-DA™ scores compared with nonresponders. The Vectra-DA™ score reflects a patient’s disease activity before and after the treatment with intravenous golimumab.

References

1. Weinblatt ME, Shadick NA, Manning W, et al. Use of a Multi-Biomarker Score for Rheumatoid Arthritis Disease Activity (Vectra™ DA) to Assess Response to Therapy.(Poster Session I: May 26, 2011, 11:45 BST). EULAR Congress 2011.

Disclosure of Interest S. Lamberth Employee of: Janssen R & D, LLC, Y. Cherkas Employee of: Janssen R & D, LLC, C. Brodmerkel Employee of: Janssen R & D, LLC, M. Curran Employee of: Janssen R & D, LLC