TNF Blockers Show Real-life Benefits in Patients, Study Finds
The extent of functional improvement correlates with both lower disease activity and shorter disease duration.
The study, “Improvement of Function and Its Determinants in a Group of Axial Spondyloarthritis Patients Treated with TNF Inhibitors: A Real-Life Study,” was published in the journal Rheumatology and Therapy.
axSpA is characterized by chronic back pain and active inflammation. It is known as ankylosing spondylitis (AS) when these changes can be seen on X-rays, and as non-radiographic (nr)-axSpA when no such damage is detected on images.
Several clinical trials have shown the effectiveness of tumor necrosis factor alpha (TNF-alpha) inhibitors in inducing improvements and clinical remission in patients, as well as better quality of life. Yet, few studies have assessed functional gains and associated clinical factors in clinical practice.
TNF inhibitors — such as Enbrel (etanercept), Humira (adalimumab), infliximab (brand names Remsima and Remicade) — reduce inflammation and disease activity by blocking TNF-alpha, a key inflammatory molecule.
A research team at Università degli Studi del Molise, with other institutions in Italy, set out to investigate the improvement of physical function and associated factors in axSpA patients treated with TNF inhibitors in a real-life setting.
A total of 183 patients with axSpA (113 males), including 27 with nr-axSpA and 156 with AS, were recruited at five Italian rheumatology centers between 2010 to 2018. All had a minimum of six months of follow-up after starting treatment with TNF blockers; their mean age was 43.3, and their median disease duration was six years.
The Bath Ankylosing Spondylitis Metrology Index (BASMI) and the Bath Ankylosing Spondylitis Functional Index (BASFI) were used to measure changes in function. Significant clinical improvement in BASFI was defined as a difference of at least two points from baseline (study start), and in BASMI as at least one point.
Results showed that, during a median follow-up of three years, 89 (48.6%) patients had a significant clinical improvement in BASMI, with 118 (64.4%) experiencing such benefit in BASFI. Median BASFI and BASMI scores significantly improved during follow-up.
Researchers also found that male sex, shorter disease duration, spinal pain, and high values of erythrocyte sedimentation rate (a marker of inflammation) at the time of starting anti-TNF treatment were associated with the improvement of BASFI, confirming the association of these factors with the extent of functional improvement. With the exception of male sex, these factors were also linked with BASMI improvement.
Lower disease activity, assessed by the Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), was also associated with improvement in BASFI.
“In conclusion, functional status in patients with axial SpA improved after treatment with anti-TNF drugs and the extent of improvement was correlated with the improvement of disease activity and with disease duration,” the scientists wrote.
“Our results confirm that, by acting in the early stage of disease in patients with high inflammatory burden, a better outcome could be obtained,” they added.