A case of glass half-full or half-empty, depending on how you see it.
AS patients with fairly early disease (3-5 years, non-radiographic inflammation) with inadequate response to at least 2 different NSAIDs were randomised to receive either Etanercept or placebo for the first year, and thereafter everyone received Etanercept for another year.
Even for those who received weekly Etanercept injections for 2 years, barely half achieved clinical remission, while 44% had sacroiliac inflammation remission on MRI, while a more respectable 78% had spinal inflammation remission on MRI. Those whose MRI inflammation remitted did not necessarily correspond to those who had clinical remission.
Where inflammation remission is concerned, is the window of opportunity for intervention closed earlier than 3-5 years? On clinical outcome measures, are certain clinical factors less reflective of actual inflammatory burden, or is radiological evidence of inflammation an inadequate measure of the totality of AS disease activity?
TNF blockers inhibit spinal radiographic progression in ankylosing spondylitis by reducing disease activity: results from the Swiss Clinical Quality Management cohort
This is an observational study of AS patients with longstanding active disease averaging 14 years. The noteworthy takeaways are:
1) Clinical measures of disease activity (ASDAS) correlated with radiographic disease progression (mSASSS), with those in clinical remission or very low disease activity having virtually no radiographic progression in this up to 10-year study;
2) Even in longstanding disease, radiographic progression can be arrested by continual anti-TNF therapy in about half of such patients;
3) The longer the duration of treatment (4 years compared to 2), the higher the probability of not having further radiographic progression (68% vs 42%).
In this 8-year follow-up of a Dutch cohort of AS patients who received anti-TNF treatment and had clinical and Xray evaluation every 2 years, the following observations were evident:
1) Clinical measures of disease activity rapidly improved, and use of NSAIDs quickly declined upon starting anti-TNF treatment;
2) The rate of radiographic progression declined steadily the longer anti-TNF was used, with virtual arrest of progression evident from Year 4 onwards.