A double ‐blind, placebo‐controlled study of rituximab in patients with stiff person syndrome

ObjectiveIn stiff person syndrome (SPS), an antibody‐mediated impaired γ‐aminobutyric acidergic (GABAergic) neurotransmission is believed to cause muscle stiffness and spasms. Most patients improve with GABA‐enhancing drugs and intravenous immunoglobulin, but some respond poorly and remain disabled. The need for more effective therapy prompted a trial with the anti‐CD20 monoclonal antibody rituximab. MethodsThis was a placebo‐controlled randomized trial of rituximab (2 biweekly infusions of 1g each). The primary outcome was a change in stiffness scores at 6 months. Secondary outcomes were changes in heightened‐sensitivity and quality of life scores. Enrolling 24 patients was calculated to detect 50% change in stiffness scores. ResultsRandomization was balanced for age, sex, disease duration, and glutamic acid decarboxylase autoantibody titers. No significant changes were noted at 6 months after treatment in all outcomes. Specifically, no differences were noted in the stiffness index, the primary outcome, or sensitivity scores, the secondary outcome, at 3 or 6 months. Quality of life scores improved significantly (p < 0.01) at 3 months in both groups, but not at 6 months, denoting an early placebo effect. Blinded self‐assessment rating of the overall stiffness for individual patients revealed improvement in 4 patients in each group. At 6 months, improvement persisted in 1 patient in the placebo group versus 3 of 4 in the rituximab group, where these meani...
Source: Annals of Neurology - Category: Neurology Authors: Tags: Research Article Source Type: research