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Rituximab to Treat Stiff Person Syndrome

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. Identifier: NCT00091897
Recruitment Status : Completed
First Posted : September 20, 2004
Last Update Posted : August 31, 2011
Information provided by:
National Institutes of Health Clinical Center (CC)

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 through a needle in an arm vein, similar to donating blood. The blood flows from the vein through a catheter (plastic tube) into a machine that separates it into its components by centrifugation (spinning). The white cells are removed and the rest of the blood (red cells, plasma and platelets) is returned to the body through a second needle in the other arm. The procedure takes about 60 to 90 minutes.
  • Lumbar puncture (spinal tap): Lumbar puncture is done to sample a small amount of cerebrospinal fluid (CSF, the fluid that bathes the brain and spinal cord), for analysis. For this procedure, the patient is given a local anesthetic and a needle is inserted into the space between the bones in the lower back where the CSF circulates below the spinal cord. A small amount of fluid is withdrawn through the needle.

Condition or disease Intervention/treatment Phase
Stiff Person Syndrome Drug: Rituximab Drug: rituximab or placebo Phase 2

Detailed Description:

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 CSF anti-GAD antibody titers, including intrathecal GAD-specific IgG synthesis, will be monitored before and after treatment. Clearance of GAD-reactive T cells will be also examined in the serum and CSF using T cell clones established from PBL and CSF. It is anticipated that the study will: a) provide a new, immune-based and target-oriented therapy for patients with Stiff Person Syndrome and b) examine the pathogenetic role of anti-GAD antibodies in the cause of the disease.

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Study Type : Interventional  (Clinical Trial)
Actual Enrollment : 24 participants
Allocation: Randomized
Intervention Model: Single Group Assignment
Masking: Double
Primary Purpose: Treatment
Official Title: Efficacy of Rituximab in Patients With Stiff Person Syndrome With Anti-GAD Antibodies: A Randomized Placebo-Controlled Trial
Study Start Date : September 2004
Actual Primary Completion Date : July 2007
Actual Study Completion Date : May 2009

Resource links provided by the National Library of Medicine

Drug Information available for: Rituximab

Arm Intervention/treatment
Experimental: Rituximab or placebo
Rituximab or placebo is administered through intravenous access on day 1 and again on day 15 (+/- 2 days)
Drug: Rituximab
Drug: rituximab or placebo
A fixed dose of Rituximab or placebo 1GM on Day 1 and 1GM on day 15 (+/- 2 days)
Other Name: Rituxan

Primary Outcome Measures :
  1. 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 ]

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

Information from the National Library of Medicine

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.

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Ages Eligible for Study:   25 Years to 80 Years   (Adult, Older Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Stiff Person Syndrome with elevated anti-GAD antibody titers.

Between 25 to 80 years of age.

Willingness to stop IVIg therapy 6 weeks prior to Rituximab/Placebo treatment and for the remainder of the study. [If receiving IVIg, patients will be allowed to receive the ongoing non-immunosuppressive drugs used to treat SPS including Diazepam, Neurontin or Baclofen. The dose of these drugs will remain stable throughout the study and unchanged for 6 weeks prior to enrollment.]

Willingness and legal ability to give and sign informed study consent.

Willingness to travel to NIH for scheduled protocol studies and treatment.

Men and women of reproductive potential must agree to use an acceptable method of birth control during treatment and for six months after completion of treatment.

Adequate bone marrow, renal, and liver function: ANC greater than 1000/mm(3), BUN/Cr in normal range for age.

Patients with Diabetes (Type II) will be allowed to participate because up to 40% of SPS patients have Diabetes.

Patients with a history of controlled epilepsy will be allowed to participate because up to 5% of SPS patients have mild epilepsy which is easily controlled.


Immunosuppressive drug therapy for SPS at the time of or 6 weeks prior to enrollment and for the remainder of the study. Specifically, candidates may not be taking prednisone, cyclosporine, tacrolimus, azathioprine, mycophenolate mofetil, anti-lymphocyte agents, cyclophosphamide, methotrexate, or other agents whose therapeutic effect is immunosuppressive.

Any medical or social condition that precludes follow-up visits.

Any active malignancy or any history of a hematogenous malignancy or lymphoma. Patients with primary, cutaneous basal cell or squamous cell cancers may be enrolled providing the lesions are treated prior to enrollment.

History of a coagulopathy or patients requiring anticoagulation.

Any history of cardiac insufficiency, major vascular disease, or symptomatic coronary artery disease. Patients with cardiomyopathy grade III or IV by the New York Heart Classification will be excluded from this study.

Systemic edema or pulmonary edema.

Chronic and severe symptomatic hypotension (SBP less than 100 mmHg).

Chronic liver disease or alcoholism.

Any condition, including active infections, that would likely increase the risk of protocol participation or confuse the understanding of the data.

Pregnancy. Serum pregnancy test will be performed and must be negative in all women of childbearing potential enrolled in the study.

History of active psychiatric disorder that may interfere with participation in the study.


Hemoglobin: less than 7.0 gm/dL.

Platelets: less than 100,000/mm.

AST or ALT greater than 2.5 x Upper Limit of Normal unless related to primary disease.

Positive Hepatitis B or C serology (Hep Surface antigen and Hep C hepatitis C antibody).

Positive HIV.

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its identifier (NCT number): NCT00091897

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United States, Maryland
National Institutes of Health Clinical Center, 9000 Rockville Pike
Bethesda, Maryland, United States, 20892
Sponsors and Collaborators
National Institute of Neurological Disorders and Stroke (NINDS)
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Responsible Party: Marinos C. Dalakas, M.D./National Institute of Neurological Disorders and Stroke, National Institutes of Health Identifier: NCT00091897    
Other Study ID Numbers: 040287
IND-BB: 11844, 04-N-0287
First Posted: September 20, 2004    Key Record Dates
Last Update Posted: August 31, 2011
Last Verified: August 2011
Keywords provided by National Institutes of Health Clinical Center (CC):
B Cells
Humanized Monoclonal Antibodies
Stiff Person Syndrome
Additional relevant MeSH terms:
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Stiff-Person Syndrome
Pathologic Processes
Autoimmune Diseases of the Nervous System
Nervous System Diseases
Spinal Cord Diseases
Central Nervous System Diseases
Neuromuscular Diseases
Autoimmune Diseases
Immune System Diseases
Antineoplastic Agents, Immunological
Antineoplastic Agents
Immunologic Factors
Physiological Effects of Drugs
Antirheumatic Agents