HERNE, Germany – Six months of treatment with infliximab (Remicade®; Centocor) significantly reduced active spinal inflammation in a randomized, double-blind placebo-controlled trial reported in the May Arthritis & Rheumatism by Jurgen Braun, MD, of the Rheumazentrum Ruhrgebiet in Herne, Germany.1 Dr. Braun and co-investigators in the Centocor- and Schering-Plough-funded Ankylosing Spondylitis Study for the Evaluation of Recombinant Infliximab Therapy (ASSERT) trial report that the TNF inhibitor reduced both the number of active lesions and their intensity, as detected by magnetic resonance imaging (MRI).

"Infliximab largely eliminated spinal inflammation in most patients with active AS," Dr. Braun told CIAOMed. "The benefit [of routine MRI monitoring] is not proven yet, but the presence of spinal inflammation may argue for anti-TNF therapy."

"Infliximab largely eliminated spinal inflammation in most patients with active AS." —Jurgen Braun, MD

The study included 194 patients randomized to receive infusions of infliximab (5 mg/kg) and 72 patients randomized to placebo at weeks 0, 2, and 6, and every 6 weeks thereafter. All had active AS for at least 3 months prior to study entry, a Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) score of >4 (range 0–10), and a spinal visual analog scale (VAS) pain score of >4 on a 0–10 cm scale. Patients were stratified by C-reactive protein (CRP) levels above or below three times the upper limit of normal.
 
The investigators took pre- and postgadolinium MRIs of the spine at baseline and at week 24. Images were scored according to activity at the level of the vertebral unit, and each vertebral unit was given an MRI Activity score based on the amount of bone marrow edema or erosions present. The total spinal MRI Activity Score range was 0–138.
 
"With MRI you can see the inflammation. With x-rays you have to wait for structural changes," Dr. Braun said.
 
Despite randomization, patients in the placebo group had a longer median duration (13.4 years vs 7.7 years) and slightly higher baseline median MRI Activity Score (5.0 vs 4.1).
 
At 24 weeks, more patients in the infliximab group had MRI Activity Scores reduced from baseline, and fewer had increases in MRI Activity Scores compared to patients in the placebo group. The mean change in MRI Activity Score was 5.0 with infliximab vs 0.6 with placebo.
 
Gadolinium-enhanced T1 MRI showed some continued spinal inflammation at week 24 in 37.1% of patients in the infliximab group vs 53 placebo patients (P <.001). "[T]he effect of infliximab on AS activity as determined by MRI is almost complete and is present in almost every patient.... [U]nlike the infliximab group, changes observed in the placebo group were sporadic, occurred in both directions (improving and worsening), were independent of baseline activity, and for the most part, did not reflect an elimination of inflammation," the authors write. "The results of this study show that treatment with the anti-TNF monoclonal antibody infliximab leads to an almost complete elimination of spinal inflammation in patients with active AS."
 
Reference
  1. Braun J, Landewe R, Hermann K-GA, et al. Major reduction in spinal inflammation in patients with ankylosing spondylitis after treatment with infliximab. Arthritis Rheum. 2006;54:1646-1652.