The European Commission ( EC ) has granted a licence extension for Enbrel ( Etanercept ) in the treatment of adult patients with severe non-radiographic axial spondyloarthritis ( nr-axSpA ).
Non-radiographic axial spondyloarthritis is a subtype of the progressive disease axial spondyloarthritis ( axSpA ), a chronic lifelong inflammatory disease for which there is no cure. It affects the spine and sacroiliac ( hip and lower spine ) joints.
Non-radiographic axial spondyloarthritis describes patients in the early stage of the disease, who experience symptoms before structural changes can be detected by X-ray.
Patients with non-radiographic axial spondyloarthritis can experience increased lower back pain and inflammation of tendons and ligaments. Nr-axSpA has been described as an early form of ankylosing spondylitis ( AS ), which is a later stage of the condition that can lead to spinal fusion.
While X-rays of patients with nr-axSpA do not show the inflammation of the sacroiliac joint, the symptoms and disease burden experienced are similar to those with ankylosing spondylitis where structural changes are visible on an X-ray. As many as 12% of nr-axSpA patients progress to ankylosing spondylitis in a two-year period.
The prevalence of axial spondyloarthritis varies depending on the classification criteria used and a recent US-based study estimated that axial spondyloarthritis could affect up to 1% of adults.
The most recent UK study estimates the prevalence of axial spondyloarthritis at 0.3%, including 0.15% for AS, which based on the latest UK population data would equate to around 95,000 patients with non-radiographic axial spondyloarthritis in the UK. The early age of onset of non-radiographic axial spondyloarthritis, most patients are under the age of 45 when symptoms begin, means that it can strike people at their most productive time of life.
The licence extension was based on data from study 1031 with Etanercept, which was a randomised 12 week double-blind, placebo-controlled, clinical trial of 215 adult patients with active non-radiographic axial spondyloarthritis.
The primary measure of efficacy was a 40% improvement in at least three of the four ASAS ( Assessment of SpondyloArthritis international Society ) domains and absence of deterioration in the remaining domain, called ASAS 40.
In study 1031 more patients treated with Etanercept showed significant improvement compared with placebo ( 32.4% versus 15.7%; p=0.006 ) in measures of disease activity and function, and decreases in inflammation on MRI by week 12.
Compared with placebo, magnetic resonance imaging assessment of the sacroiliac joint demonstrated a significant improvement for patients receiving Etanercept at week 12. Clinical outcomes improved further after all patients were treated with open-label Etanercept between weeks 12–24.
Treatment-related adverse events were reported in 57% and 45% of patients in the Etanercept and placebo groups, respectively. In the open-label period, such events were reported in 34% of patients in the Etanercept / Etanercept group and 50% in the placebo / Etanercept group.
The EC approval is for the treatment of adults with severe non-radiographic axSpA with objective signs of inflammation as indicated by elevated C-reactive protein and/or MRI evidence, who have had an inadequate response to non-steroidal anti-inflammatory drugs ( NSAID ). ( Xagena )
Source: Pfizer, 2014