TNF-inhibitor tapering as effective as standard dose in axial SpA
Mild TNF inhibitor tapering is about as efficacious as the standard dose treatment in achieving inactive disease in patients with axial spondyloarthritis, according to data published in Arthritis Research & Therapy.
“The efficacy of long-term TNF [inhibitor] treatment has been demonstrated by several randomized controlled trials and large cohort studies,” Eun Young Lee, MD, PhD, MS, of the Seoul National University College of Medicine, South Korea, and colleagues wrote. “However, the long-term use of TNF [inhibitor] could increase economic burden on patients and the risk of infection and possibly some kinds of malignancy. However, several patients continue TNF [inhibitor] treatment despite maintaining persistent stable disease activity because treatment discontinuation usually leads to flares.”
They added, “Moreover, information regarding patients in whom tapering should be tried and how it should be performed is limited, which is a hurdle for the application of the tapering strategy in real-world clinical settings.”
To determine how tapering TNF inhibitors would impact the likelihood of achieving inactive disease status among patients with axial SpA, Lee and colleagues collected data from the Korean College of Rheumatology Biologics Registry, a nationwide cohort of patients with inflammatory arthritis treated with biological DMARDs. According to the researchers, there were 1,462 patients with axial SpA who started treatment with TNF inhibitors in the cohort as of January 2017. Each patient completed annual follow-up visits.
Lee and colleagues analyzed 1,575 one-year follow-up dosing intervals from 776 patients. Among those, 1,091 intervals were in the control group, 440 were in the mild-tapering group and 44 followed heavy tapering. The researchers quantified the TNF inhibitor dose during a 1-year follow-up interval as a dose quotient, calculated as (mean actual dose/standard dose)×(standarddosing interval/mean actual dosing interval)×100. Heavy tapering was defined as a dose quotient of less than 50, mild tapering as 50 to 99 and the control group as a quotient of 100.
Outcome variables included Ankylosing Spondylitis Disease Activity Score-inactive disease (ASDAS-ID), defined as an ASDAS-CRP of less than 1.3, as well as a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI50) major clinical response, in the follow-up.
According to the researchers, 91.1% of patients demonstrated high disease activity, defined as an ASDAS-CRP of 2.1 or more, at baseline. The dose quotient of each interval was significantly impacted by the ASDAS-CRP in the prior follow-up (P<.001). In their analysis, the researchers found that the likelihood achieving ASDAS-ID was similar between the control and mild-tapering groups, but significantly decreased in the heavy-tapering group (OR compared with control=0.28; 95% CI, 0.08-0.94). However, the likelihood of achieving BASDAI50 was no different among the groups.
Among the 327 patients who achieved ASDAS-ID 1year after starting TNF inhibitors, inactive disease was maintained in 66.1% of subsequent dosing intervals. Only intervals in the mild-tapering group demonstrated a likelihood of target maintenance comparable with the controls (OR=1.25; 95% CI, 0.41-3.8). However, this likelihood decreased as ASDAS-CRP increased.
“Our study showed that mild tapering of TNF [inhibitor] had efficacy comparable with that of the standard-dose treatment in maintaining the optimal target in patients with axSpA who reached ASDAS-ID 1year after TNF [inhibitor] treatment,” Lee and colleagues wrote. “Although this result should be confirmed with randomized studies in the future, it provides important real-world evidence for universal recommendation of the tapering strategy.” – by Jason Laday
Disclosure: The researchers report no relevant financial disclosures.