PracticeUpdate: Dermatology & Rheumatology

AMERICAN COLLEGE OF RHEUMATOLOGY 2016 ANNUAL MEETING 24

Longer biologic use for RA linked with reduced disability, disease activity Longer biologic exposure was associated with reduced disease activity and disability in a longitudinal population of patients with rheumatoid arthritis, results of a retrospective analysis covering a 12-year period show. N ancy Ann Shadick, MD, MPH, of Brigham and Women’s Hospital, Boston, Massachu- setts, explained that biologics have become

The analysis included 1395 patients with rheumatoid arthritis, 82.2% female, with a total of 6783 unique physician visits from 2003 to 2015. Average disease duration at enrolment was 12.7 years. Longer biologic exposure was associated with a significant reduction in annual population means for both disease activity and disability (P < 0.0001). Disease Activity Score 28 or modified Health Assessment Question- naire score at enrolment was the strongest predictor of disease activity and disability in models, respectively (P < 0.0001). Shorter disease duration (P < 0.0001), not using a biologic at enrolment (P < 0.0001), and use of methotrexate (P < 0.0003) were significant predictors of reduced disease activity and disability in the models. Dr Shadick concluded that longer biologic exposure was associated with reduced disease activity and disability in a longitudinal population of patients with rheumatoid arthritis. Though biologic use improves the functional status of the population, rheumatoid arthritis status at enrolment remains the most significant predictor of disability. Results of the developed longitudinal models suggest that use of biologics may help reduce long-term disease activity and disability in patients afflicted with rheumatoid arthritis. She added, “This study, drawn from data in the Brigham and Women’s Hospital Rheumatoid Arthritis Sequential Study (BRASS) registry, a real world setting cohort, demonstrated that, of patients who remain on biologic therapy, good outcomes, improved functional status, and reduced disease activity are observed.” When asked about future directions of her team’s work, Dr Shadick responded, “We will look at the impact of methotrexate use in conjunc- tion with biologic therapy on these outcomes, how biologic therapy impacts ongoing radiographic progression in longstanding disease, and to what extent reduced disability and disease activity affects a cost-effectiveness model.”

the standard of care for treating moderate to severe rheumatoid arthritis in patients with an inade- quate response to nonbiologic disease-modifying antirheumatic drugs. Though biologics have been proven effective in managing symptoms and dis- ease activity, their long-term impact on disability

remains unclear. Dr Shadick said, “Limiting the long term functional impairment that can occur in rheumatoid arthritis is a very important goal.” She continued, “While biologic therapy is known to improve disease activity and symptoms of rheumatoid arthritis, understanding the long-term impact of biologic therapy on functional capacity in patients with rheumatoid arthritis of longer duration is important.” Dr Shadick and colleagues used longitudinal data from a cohort of patients with rheumatoid arthritis at a single academic medical centre to examine the link between patient disability due to rheumatoid arthritis and biologic exposure. Linear mixed repeated measures regression was used to model the impact of biologic exposure on changes in disease activity (Disease Activity Score 28 C-reactive protein) and disability (modified Health Assessment Questionnaire). At each follow-up visit, biologic exposure was quantified as the ratio of a patient’s time on a biologic relative to their time participating in the cohort. Patients’ yearly biologic exposure, outcome scores, and associated covariates were incorporated over a maximum of 13 years into the longitudinal regression models to identify predictors of disease activity and disability at the population level.

Three gene sets could predict response to therapies for RA Three gene expression signatures can help rheumatologists identify patients more likely to respond to tumour necrosis factor inhibitors or B-cell depletion therapies in patients with moderate

Dr Porter, said, “The ORBIT data showed that patients with seropositive rheumatoid arthritis are as likely to respond to rituximab as to anti-tumour necrosis factor therapy. A significant proportion of patients failed to re- spond to their first biologic drug, however, but responded when switched to the alternative.” He continued, “If we could identify blood markers that predict which drug patients were most likely to respond to, that would allow us to choose the best treatment for that patient at the start, rather than rely on a trial-and-error approach.” Dr Porter and colleagues sequenced the RNA from the peripheral blood of 241 patients with rheumatoid arthritis recruited for the ORBIT study, after first depleting ribosomal

to severe rheumatoid arthritis. T his conclusion was based on results of RNA sequencing of blood from patients participating in the Optimal management of Rheumatoid arthritis patients requiring BIologic Therapy (ORBIT) study. Duncan Porter, MD, of Queen Elizabeth University Hospital, Glasgow, UK, explained

that ORBIT was a randomised, controlled trial of patients with rheumatoid arthritis in the UK. Drawing on data from ORBIT, researchers looked for gene expression markers that would help predict responses to either tumour necrosis factor inhibiting drugs or the B-cell therapy rituximab, or both.

PRACTICEUPDATE RHEUMATOLOGY & DERMATOLOGY