Objective: Tumor necrosis factor-alpha (TNF-alpha) has been detected in sacroiliac joints of patients with spondyloarthropathies (SpA). Anti-TNF-a therapy has been efficacious in patients with active ankylosing spondylitis (AS) and psoriatic arthritis. Similar to these SpA subtypes, therapeutic options in undifferentiated SpA (uSpA) are also limited. We tested the efficacy of the monoclonal anti-TNF-alpha antibody infliximab in patients with active and severe uSpA in an open observation trial.
Methods: Six patients with uSpA were treated with 3 infusions of infliximab in a dosage of 3 (n = 3) or 5 mg/kg (n = 3) at Weeks 0, 2, and 6. The total observational period was 12 weeks. The Bath AS Disease Activity Index (BASDAI), the Functional Index (BASFI), pain on a visual analog scale, the Bath AS Metrology Index (BASMI), and quality of life (SF-36) were assessed before, during, and after therapy.
Results: Significant improvement at Day 1 after the first infusion lasting until Week 12 was reported by 5/6 patients. Improvement of > or = 50% in all activity, function, pain, and swollen joint scores was observed in the patients taking 5 mg/kg. The 3 mg/kg dose was less effective, resulting in > or = 15% improvement in outcome variables. Peripheral arthritis, enthesitis, and spinal symptoms improved equally. C-reactive protein dropped in 4 patients. Health related quality of life increased. No serious side effects or infections occurred.
Conclusion: These observations suggest that anti-TNF-alpha therapy has significant short term efficacy in patients with severe uSpA.