Exploring treatment response in AS versus non-radiographic axSpA

Concept

Ankylosing spondylitis (AS) is the severe, end stage phenotype of axial spondyloarthritis (axSpA), which also comprises an earlier, undifferentiated state, referred to as non-radiographic axSpA. Although biologics have revolutionized the management of patients with axSpA, there are limited data evaluating the treatment response between subjects with AS and nr-axSpA. Controversy remains as to whether nr-axSpA represents a milder form with biologic DMARD (bDMARD) treatment restrictions still in place in many countries.

Facts and figures

Project lead
X Michelena Vegas
Hospital Universitari de Bellvitge
xmichelena@bellvitgehospital.cat
FOREUM research grant: €50'000
2019–2020

Meet the team

X Michelena Vegas
Hospital Universitari de Bellvitge
JM Nolla Solé
Hospital Universitari de Bellvitge
H Marzo-Ortega
University of Leeds

Objectives

Primary objective: To examine the baseline characteristics in axSpA patients in the British Society for Rheumatology Biologics Register in Ankylosing Spondylitis (BSRBR-AS) according to radiographic status.

Secondary objective: To explore treatment response to bDMARDs at 1 year as well as drug survival according to radiographic status (nr-axSpA vs r-axSpA)

Interim results

Baseline characteristics were available for 1,145 patients. Those with r-axSpA were more likely to be male, were older, and had longer disease duration.

Follow-up ASDAS at 1 year was available in 290 patients. Two thirds of the patients achieved ASDAS low disease state at one year regardless of radiographic status (nr-axSpA: 64.2% vs r-axSpA: 66.1, Diff: -1.9%, 95% CI -13.7 to 9.8). Further, no significant differences were seen between the groups in attaining ASDAS CII (nr-axSpA: 50.7% vs r-axSpA: 44.7%, Diff: 6.0%, 95% CI -7.8 to 19.8%) or MI (nr-axSpA: 20% vs r-axSpA: 18.7%, Diff: 1.3%, 95% CI -9.7 to 12.3%).

Although there appeared to be some differences in the baseline characteristics when exploring this cohort, according to radiographic status, which are likely related to the natural history of the disease; the level of biologic response was comparable between the groups supporting the concept of axSpA as a single disease entity.

Patient Voice

The research team is directly involved with patient initiatives such as the National Ankylosing Spondylitis Team (NASS) and has discussed the objectives and preliminary results with patient representatives. The results from this project will aid in the understanding of axSpA as a single disease entity and promote better access to bDMARDs for axSpA patients.

Publications

EULAR Abstracts

2020

  • FRI0287: Biologic drug response does not appear related to radiographic status in axial Spondyloarthritis: data from the BSRBR-AS registry

Go to EULAR Abstract Archive