Baricitinib Lowers Structural Joint Damage in Patients With Rheumatoid Arthritis

An oral dose of baricitinib was shown to maintain lower levels of radiographic progression in patients with active rheumatoid arthritis (RA) when compared with those receiving conventional synthetic drug-modifying antirheumatic drugs (csDMARDs) or placebo through 5 years according to a study published in the Journal of Rheumatology.¹

“Because no cure for RA exists, it is important to reduce a patient’s inflammation to the lowest level possible to prevent structural damage from accruing and thereby maintaining patients’ functional ability,” investigators stated. “DMARDs can reduce joint pain and swelling and can provide protection against structural damage in a clinically meaningful way. However, structural damage progression still occurs in some patients, even when they achieve adequate clinical control of their disease with DMARDs.”

Patients with RA who completed 1 of 3 trials, RA-BEGIN (DMARD naïve), RA-BEAM (intolerance to methotrexate [MTX-IR]), or RA-BUILD (csDMARD-IR) who additionally enrolled in RA-BEYOND were included in the study. Patients in the 3 studies were allowed to receive nonsteroidal anti-inflammatory drugs (NSAIDs), analgesic therapy, or corticosteroids. In the RA-BEYOD study, efficacy of 4 or 2 mg of oral baricitinib was analyzed (n = 1873). Throughout all trials, patients who were initially being treated with methotrexate (MTX) or adalimumab were switched to baricitinib 4 mg at week 52. Those receiving a placebo were switched to baricitinib at week 24. Radiographic scores were collected at baseline, 2, 3, 4, and 5 years, or at early termination points, and included images of wrists, hands, and feet. Structural joint damage was determined by changes from baseline as well as both erosion score (ES) and joint space narrowing (JSN) in subsequent follow-up visits.

Baseline changes in van der Heijde modified Total Sharp Score (∆mTSS) were determined and efficacy was analyzed via low disease activity (LDA) at years 2, 3, 4, and 5.

Demographics, American College of Rheumatology (ACR) core set values, and disease activities were collected and were similar between all treatment groups.

A total of 82.6% (n = 2125) in RA-BEYOND were analyzed. In years 3 to 5, DMARD-naïve patients on baricitinib had no progression versus those in the initial MTX cohort.

More patients with MTX-IR receiving baricitinib 4 mg and adalimumab had no progression in radiographic progression at year 5 when compared with placebo (54.8%, 55.0%, and 50.3%, respectively). Patients on initial baricitinib 4 mg and MTX had smaller mean changes from baseline at years 2, 3, 4, and 5 when compared with those on initial placebo. DMARD-naïve patients on baricitinib 4 mg monotherapy or baricitinib and MTX had fewer signs of radiographic progression when compared with those on initial MTX and subsequent baricitinib at years 2 through 5.

Patients receiving baricitinib 4 mg and csDMARDs had the smallest mean changes in radiographic progression from years 2 though 5 and a significant proportion in this group had no radiographic progression compared to either the baricitinib 2 mg or in the initial placebo cohort.

More patients treated with baricitinib 4 mg and baricitinib 4 mg with MTX had no radiographic progression when compared with those receiving initial MTX monotherapy at 3, 4, and 5 years.

The study was strengthened by following patients for a prolonged period to determine whether baricitinib influenced radiographic progression. Results were likely generalizable to patients with RA as many patients were either receiving baricitinib monotherapy or csDMARDs. However, the lack of a true placebo or ADA group during the LTE limited the study. Additionally, the administration of background medication may have impacted results. As a percentage of patients did not participate in the study for the entire 5 years, investigators are not able to predict how that patient population would have fared if they continued baricitinib therapy. The clinical trials did not include all patients treated in clinical practice and the ad hoc nature did not compare doses.

“Both 2 mg and 4 mg baricitinib maintained inhibition of radiographic progression in most patients while achieving clinically meaningful improvement in disease activity, sustained for 5 years,” investigators stated. “This observation suggests that one should start a medication such as baricitinib earlier in the disease course if patients have not reached remission, according to ACR/European League Against Rheumatism criteria or at least LDA with a metric such as the SDAI or CDAI, within 3 to 6 months as suggested by the treat-to-target strategy.”

Reference:

van der Heijde D, Kartman CE, Xie L, et al. Radiographic progression of structural joint damage over 5 years of baricitinib treatment in patients with rheumatoid arthritis: Results from RA-BEYOND [published online ahead of print, 2021 Sep 15]. J Rheumatol. 2021;jrheum.210346. doi:10.3899/jrheum.210346