Add-on Xeljanz controls disease as treatment for non-responding AS
15 adults with moderate to high disease activity despite DMARDs use studied
Adding Xeljanz (tofacitinib) to treatment with biologic disease-modifying anti-rheumatic drugs (DMARDs) when these medications aren’t working well may help adults with ankylosing spondylitis (AS) keep their disease activity under control, a study suggests.
Because the study included only a few patients, “further prospective randomized controlled trials with large sample sizes are anticipated to provide evidence-based medical support,” wrote two researchers from Zhejiang University School of Medicine, China in “The efficacy of tofacitinib combined with bDMARDs in the treatment of ankylosing spondylitis patients with inadequate response to bDMARDs: a retrospective study,” which was published in BMC Rheumatology.
AS occurs when the joints of the spine and sacroiliac joints, where the base of the spine meets the pelvis, become inflamed and stiffen. Lasting inflammation can cause many symptoms, from pain and swelling to fatigue and heart problems.
Treatment with biologic DMARDs, which reduce inflammation primarily by blocking the key inflammatory mediator tumor necrosis factor (TNF) or interleukin-17 (IL-17), can ease symptoms of AS. Not everybody responds well to these medications, however.
Marketed by Pfizer, Xeljanz is an oral JAK inhibitor approved in the U.S. for adults with active AS and other inflammatory conditions who’ve had an inadequate response or are intolerant to one or more TNF blockers.
Using Xeljanz with biologic DMARDs is not recommended in the U.S., but it’s unclear how safe add-on Xeljanz is or how well it works on top of biologic DMARDs when these medications aren’t working well or can’t be tolerated.
Reducing AS disease activity
The researchers reviewed the medical records of 15 adults (11 men, four women) with AS, ages 21-44, who had moderate to high disease activity despite being on biologic DMARDs for more than three months. All received Xeljanz at 5 mg twice daily on top of their biologic DMARDs for at least 12 weeks, or about three months.
Five adults took adalimumab (marketed as Humira and biosimilars), four etanercept (sold as Enbrel and biosimilars), three infliximab (marketed as Remicade or biosimilars), and another three the IL-17A blocker Cosentyx (secukinumab).
Disease activity was evaluated with the AS Disease Activity Score (ASDAS-CRP), which stratifies disease severity using clinical data and blood levels of C-reactive protein, a marker of inflammation. A higher score indicates more severe disease.
After 12 weeks, the average ASDAS-CRP decreased from 3.82 to 1.47 points, indicating less severe disease. The largest change was seen in those who took infliximab, where ASDAS-CRP dropped from 4.22 to 1.63 points.
Seven (46.7%) patients went into remission, defined as an ASDAS-CRP of 1.3 points or less. Low disease activity, defined as an ASDAS-CRP equal to or more than 1.3 points, but not more than 2.1 points, was achieved in five (33.3%) adults.
Similar findings were seen on the Bath AS Disease Activity Index (BASDAI), which fell from 5.11 to 1.28 points after 12 weeks, indicating less severe disease.
The erythrocyte sedimentation rate, which measures how quickly red blood cells sink to the bottom of a tube, decreased from 44.9 to 14.3 mm per hour, indicating less inflammation.
The levels of C-reactive protein, made by the liver and released into the bloodstream when there is inflammation, also fell by about six times from 30.47 to 4.99 mg per liter.
Add-on Xeljanz was safe and well tolerated, and no serious side effects were reported. Two patients had mild stomach discomfort and one had a mild infection of the upper airways, which resolved with treatment.
Adding Xeljanz to biologic DMARDs “effectively controls disease activity while maintaining a relatively low and manageable incidence of adverse events,” wrote the researchers, who said more research is needed to confirm their findings.
