Clinical Trial: Rituximab to Treat Stiff Person Syndrome

Study Status: Completed
Recruit Status: Completed
Study Type: Interventional

Official Title: Efficacy of Rituximab in Patients With Stiff Person Syndrome With Anti-GAD Antibodies: A Randomized Placebo-Controlled Trial

Brief Summary:

This study will test whether rituximab (RITUXAN (Trademark)) can relieve symptoms of stiff person syndrome (SPS), a progressive disease that causes stiffness of the muscles and muscle spasms induced by unexpected noises, touches, or stressful events. People with SPS may have certain proteins in their blood called anti-GAD antibodies that may cause some of the symptoms of the disease. Rituximab, a drug approved to treat lymphomas, targets certain white blood cells that produce antibodies. This study will see if rituximab can also be effective in patients with SPS who have high anti-GAD antibodies.

Patients between 25 and 80 years of age with SPS may be eligible for this study. Candidates are screened with a medical history, physical examination, and blood tests. Participants undergo the following tests and procedures:

  • Rituximab or placebo treatment: Patients are randomly assigned to receive two infusions by vein of either rituximab or placebo (a look-alike solution with no active ingredient) 2 weeks apart. The infusions last from 3 to 4 hours, but may take as long as 16 hours if the rate must be slowed for any reason. Patients are followed monthly for up to 6 months and then every 2 months for up to 1 year after treatment.
  • Medical history and interview, physical and neurological examinations: Patients are questioned about their vaccination history, medical, surgical, and psychiatric history, exposure to environmental toxins or viruses, and family and social history, including habits and employment.
  • Blood drawing: Blood samples are collected before the two infusions and at all follow-up visits.
  • Apheresis: For this procedure, which is used to collect white blood cells, blood is collected thr

    Detailed Summary:

    This study will examine the safety, tolerability, and efficacy of the humanized monoclonal antibody Rituximab to induce a clinical and serological remission in patients with Stiff Person Syndrome (SPS) associated with high anti-GAD antibodies. Rituximab is a monoclonal antibody specific for the common B cell antigen CD20. Its administration depletes pre-B and mature B lymphocytes without altering neutrophils or hematopoietic stem cells. In humans with indolent B cell lymphomas, Rituximab can be safely administered, is well tolerated, promotes selective B cell depletion and lowers the serum IgG and IgM levels. Preliminary experience in some non-malignant antibody-mediated disorders has shown that Rituximab was beneficial in improving the patients' symptoms and reducing antibody level.

    SPS is an antibody-mediated autoimmune disease affecting GABA-ergic transmission resulting in incapacitating stiffness and spasms. The anti-GAD antibodies are also produced intrathecally and it is believed to be responsible for the reduction of GABA level in serum and CSF. Although removal or modulation of serum antibodies by plasmapheresis or IVIg results in clinical improvement, a number of patients do not respond or their response is modest and short-lived, and remain with significant disability. The need for more effective therapy prompted us to conduct the present study to examine in a randomized trial if Rituximab is effective in patients with GAD-antibody-positive SPS.

    Twenty-four patients will be randomized, in a double blind fashion, to receive placebo or Rituximab given at a fixed dose of 1 GM on Day 1and 1 GM on day 15 (plus or minus 2 days). The primary outcome will be based on measurements of stiffness using the Distribution of Stiffness Index. Secondary outcomes will be measured by the Heightened-Sensitivity Scales. The serum and
    Sponsor: National Institute of Neurological Disorders and Stroke (NINDS)

    Current Primary Outcome: To evaluate the efficacy, safety of the chimeric monoclonal antibody Rituximab to deplete B lymphocytes in patients with Stiff Person Syndrome with high anti-GAD antibodies. [ Time Frame: 2 Years ]

    Original Primary Outcome:

    Current Secondary Outcome: The Heightened Sensitivity Scale will be used as a secondary outcome measure. [ Time Frame: 2 Years ]

    Original Secondary Outcome:

    Information By: National Institutes of Health Clinical Center (CC)

    Dates:
    Date Received: September 18, 2004
    Date Started: September 2004
    Date Completion:
    Last Updated: August 30, 2011
    Last Verified: August 2011