The treatment of disc herniation-induced sciatica with infliximab -: One-year follow-up results of FIRST II, a randomized controlled trial

Study Design. A randomized controlled trial. Objectives. To evaluate the long-term efficacy of infliximab, a monoclonal antibody against tumor necrosis factor alpha (TNF-alpha), in patients with acute/subacute sciatica secondary to herniated disc. Summary of Background Data. The results of experimental studies and our open-label trial support the use of infliximab in sciatica. Here we report the 1-year results of a randomized controlled trial (FIRST II, Finnish Infliximab Related STudy) evaluating the efficacy and safety of a single infusion of infliximab for sciatic pain. Methods. Inclusion criteria were unilateral sciatic pain with a disc herniation concordant with the symptoms and signs of radicular pain. Patients had to be candidates for discectomy. Criteria for discectomy included (in addition to a symptomatic disc herniation on MRI) neural entrapment (straight leg raising [SLR] <= 60 degrees) with either a short-term (2-4 weeks) severe or long-term (4-12 weeks) moderate leg pain. Forty patients were allocated to a single intravenous infusion of either infliximab 5 mg/kg or placebo. Differences in the clinical examination parameters (straight leg raise [SLR], muscle strength, sensory defects, tendon reflexes), patient-reported symptoms (leg and back pain using a visual analog scale [VAS], Oswestry disability, quality-of-life [RAND-36]), sick leaves, number of discectomies, and adverse effects between the two treatment groups over the 1-year follow-up were compared using Mann-Whitney U test or Student's t test, repeated-measures analysis, or Cox proportional hazards model. Logistic regression was used to assess the predictors of good response. Results. Sixty-seven percent of patients in the infliximab group reported no pain at 52 weeks compared with 63% in the control group (P = 0.72). Similar efficacy was observed between treatment groups for other outcomes. Eight patients in each group required surgery. Three non-serious adverse reactions were encountered in the infliximab group. The response ( irrespective of the treatment) was significantly better with shorter symptom duration and less SLR restriction at baseline. Patients in the infliximab group appeared to especially benefit in cases of a L4-L5 (or L3-L4) herniation and if a Modic change was colocalized at the symptomatic level. Conclusions. Although the long-term results of this randomized trial do not support the use of infliximab compared with placebo for lumbar radicular pain in patients with disc herniation-induced sciatica, further study in a subgroup of patients with L4-L5 or L3-L4 herniations, especially in the presence of Modic changes, appears to be warranted.