Objective. To evaluate the efficacy and safety of the tumor necrosis factor (TNF) antagonist adalimumab in patients with axial spondylarthritis (SpA) without radiographically defined sacroiliitis refractory to conventional treatment.Methods. Patients with active axial SpA (n ‫؍‬ 46) were randomized to receive placebo or adalimumab at a dosage of 40 mg subcutaneously every other week for 12 weeks, followed by an open-label extension that continued up to week 52. The diagnosis of axial SpA required the presence of 3 of 6 diagnostic criteria, including 2 of the following 3 criteria: inflammatory back pain, HLA-B27 positivity, or acute inflammation of the spine or sacroiliac joints on magnetic resonance imaging, in the absence of radiographic evidence of sacroiliitis. The primary end point was a 40% response according to the improvement criteria of the Assessment of SpondyloArthritis international Society (ASAS40).Results. All 46 patients (22 receiving adalimumab and 24 receiving placebo) completed the 12-week trial; 38 patients completed the extension period to week 52. At week 12, an ASAS40 response was achieved by 54.5% of the adalimumab-treated patients, as compared with 12.5% of the placebo-treated patients (P ‫؍‬ 0.004). After switching to adalimumab, a similar degree of efficacy was also achieved by the patients who were initially treated with placebo. Efficacy was maintained in all patients until week 52. Young age at study entry and an elevated C-reactive protein concentration were the best predictors of achieving an ASAS40 response. Serious adverse events occurred in 5 patients, none of which was related to the study drug.Conclusion. Adalimumab is the first TNF antagonist to demonstrate good clinical efficacy and safety in patients with axial SpA without radiographically defined sacroiliitis.The tumor necrosis factor (TNF) antagonists adalimumab, etanercept, and infliximab have all been proven to be highly effective in the treatment of patients with ankylosing spondylitis (AS) that continued to be active despite treatment with nonsteroidal antiinflammatory drugs (NSAIDs) (1-4). In all of these studies, an ClinicalTrials.gov identifier: NCT00235105.

Objective To study the relationship of spinal inflammation and fatty degeneration (FD) as detected by MRI and new bone formation seen on conventional radiographs (CRs) in ankylosing spondylitis (AS). Methods CRs at baseline, 2 years and 5 years and spinal MRIs at baseline and 2 years of 73 AS patients treated with infliximab in European AS Infliximab Cohort were available. Relative risks (RR) were calculated with a general linear model after adjustment for within-patient variation.Results In a total of 1466 vertebral edges (VEs) without baseline syndesmophytes, 61 syndesmophytes developed at 5 years, the majority of which (57.4%) had no corresponding detectable MRI lesions at baseline. VEs with both inflammation and FD at baseline had the highest risk (RR 3.3, p=0.009) for syndesmophyte formation at 5 years, followed by VEs that developed new FD or did not resolve FD at 2 years (RR=2.3, p=0.034), while inflammation at baseline with no FD at 2 years had the lowest risk for syndesmophyte formation at 5 years (RR=0.8). Of the VEs with inflammation at baseline, >70% resolved completely, 28.8% turned into FD after 2 years, but only 1 syndesmophyte developed within 5 years. Conclusions Parallel occurrence of inflammation and FD at baseline and development of FD without prior inflammation after 2 years were significantly associated with syndesmophyte formation after 5 years of antitumour necrosis factor (TNF) therapy. However, the sequence 'inflammation-FD-new bone formation' was rarely observed, an argument against the TNF-brake hypothesis. Whether an early suppression of inflammation leads to a decrease of the risk for new bone formation remains to be demonstrated.

Objective. Histologic studies have shown B cell clusters in the subchondral bone marrow of the spine of patients with ankylosing spondylitis (AS). An immunotherapy targeting B cells in AS is therefore of interest.We undertook this study to examine the efficacy and safety of rituximab in patients with AS refractory to nonsteroidal antiinflammatory drugs in whom previous treatment with tumor necrosis factor ␣ (TNF␣) blockers either had not been tried or had failed.Methods. In this phase II clinical trial, 1,000 mg rituximab was administered intravenously at baseline and at week 2 in 20 patients with active AS. Ten of these patients had never received TNF blockers, and treatment with TNF blockers had failed in the other 10 patients. The primary end point was a 20% improvement in disease activity at week 24 according to the criteria of the Assessment of SpondyloArthritis international Society (an ASAS20 response).Results. Seventy-five percent of the patients were male, 90% were HLA-B27 positive, their mean age was 39.7 years, and their mean disease duration was 16.8 years. Patients had active disease, defined as a Bath Ankylosing Spondylitis Disease Activity Index (BAS-DAI) score >4. While there was no clear response at week 24 in the group in whom TNF blockers had failed (30% had achieved an ASAS20 response, 10% had achieved an ASAS40 response, none had achieved partial remission according to the ASAS criteria, and none had achieved 50% improvement on the BASDAI [a BASDAI50 response] beyond an expected placebo response), we observed a good improvement in the TNF blocker-naive group at week 24 (50% had achieved an ASAS20 response, 40% had achieved an ASAS40 response, 30% had achieved partial remission according to the ASAS criteria, and 50% had achieved a BAS-DAI50 response).Conclusion. Although rituximab does not seem to be effective in patients with AS that does not respond to TNF blockers, it had significant efficacy in TNF blocker-naive patients. Therefore, further controlled trials with B cell-directed therapies should be performed in TNF blocker-naive AS patients in the future.

In this pilot open-label AS study a major response was not observed.