ClinicalTrials.gov record NCT07552987

A Study Investigating Intravenous Human Normal Immune Globulin 10% in Adults With Stiff Person Syndrome

Record copied from ClinicalTrials.gov: Oct 10, 2026AI summaries generated: Jul 27, 2026

A Phase III, Randomized, Double-blind, Placebo-Controlled, Parallel Group, Multicenter Study to Assess the Efficacy and Safety of Intravenous Human Normal Immune Globulin (IGIV) 10% in Adult Patients With Stiff Person Syndrome

StatusNot yet recruitingThe study has been registered but has not started enrolling. Sites and contacts may not be listed yet.
Study typeInterventionalA study in which researchers assign participants to one or more interventions, such as a drug, procedure, device, behavioural programme or other approach, to measure their effects.
PhasePhase 3A later-stage study, usually with more participants, designed to give stronger evidence about how well a treatment works and how safe it is. It often compares the treatment with standard care or a placebo, and results may support an application for approval.
Age18 years old to 70 years old
SexAll
AI summaryWhat this study is about, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

This Phase 3, randomized, double-blind study compares intravenous human normal immunoglobulin (IVIg 10%, QIVIGY) with placebo in adults diagnosed with stiff person syndrome. Participants are assigned 1:1 to receive 2 g/kg IVIg or matching placebo every 4 weeks for 24 weeks. At Week 24 there is an option to enter a 24-week open-label extension during which participants can receive IVIg.

What it is studying. The study is testing the effects of IVIg 10% (QIVIGY) given every 4 weeks versus placebo on walking ability (Timed 25-Foot Walk) and on safety measures in adults with SPS.

What the researchers hope to learn. To assess whether IVIg 10% (QIVIGY) has an effect on walking performance (primary measure: Timed 25-Foot Walk) and to collect data on other measures such as stiffness distribution, sensitivity, functional status, quality of life, pain, walking-aid use, safety, duration of response, and time to response.

What this study is about

The study's own summary, as published on ClinicalTrials.gov. Underlined terms have a short explanation.

The purpose of this study is to evaluate the efficacy and safety of QIVIGY (Intravenous Human Normal Immune Globulin 10%) compared with placebo in adult participants with stiff person syndrome (SPS).

Interventions being studied

Being studied in this trial does not mean the treatment or procedure is approved or available for this condition.

Biological
  • Kedrion IVIg 10%
  • Human Albumin

Eligibility

The criteria exactly as listed on ClinicalTrials.gov. Only the study team can say whether they apply to you.

Inclusion criteria

  • Male or female, 18-70 years of age.
  • Patient has signed the Informed Consent Form (ICF).
  • Diagnosed with SPS per the following criteria:
  • a. Clinical symptoms (must have 1 of 2) i. Stiffness (axial regions, limbs, or both) ii. Episodic spasms (axial regions, limbs, or both) triggered by noises, tactile stimuli, emotional stress.
  • b. Clinical signs during symptomatic phase of illness (must have 1 of 3) i. Increased muscle tone (axial or limbs) ii. Exaggerated lumbar lordosis iii. Concurrent stiffness of lumbar paraspinal and abdominal muscles. c. Serological findings (must have 1 of 2), based on participant medical history: i. High-titer GAD65-IgG in the serum (e.g. ≥ 20 nmol/L by radio-immunoprecipitation assay or 10,000 IU/mL by enzyme-linked immunoassay [ELISA]) or any positive titer in cerebrospinal fluid [CSF] ii. Glycine-R-IgG in serum and/or CSF by live cell binding assay.
  • Patients must have paravertebral stiffness and torso/lower extremity predominance.
  • Distribution of stiffness index score of ≥ 2, including stiffness in the legs or trunk.
  • Patient may be Ig-naïve or Ig-pre-treated, however they should not have received Ig within 3 months prior to the time of study entry (Day 0).
  • Includes newly diagnosed patients
  • Includes patients who have received symptomatic treatments only
  • Includes patients who have failed to respond to rituximab.
  • Patients who have received rituximab in the past 18 months must have B-cell reconstitution test results available from within 3 months prior to enrolment that confirms restoration of humoral immunity.
  • Daily symptomatic therapy has been stable for a minimum of two weeks prior to screening and is expected to remain stable throughout the duration of the study.
  • Willing to comply with all requirements of the protocol, including travel to site for scheduled protocol assessments and treatment, and completion of a diary for the study duration.
  • For women of childbearing potential (WOCBP), a negative urine pregnancy test at screening, on enrollment (Day 0), and agreement to employ effective birth control measures during the study until the end of study (EOS) visit.
  • Authorization to access personal health information.

Exclusion criteria

  • Patients incapable of giving informed consent.
  • Patients with SPS-plus or variants of SPS such as paraneoplastic or progressive encephalomyelitis with rigidity and myoclonus (PERM). Patients with pure cerebellar ataxia, ocular motor apraxia.
  • Patients who are bed-bound or wheelchair-dependent.
  • Ongoing/active infection with hepatitis B virus (HBV), hepatitis C virus (HCV) or HIV Type 1/2 infection. Subjects with chronic hepatitis B or hepatitis C infection currently on treatment may participate if they have undetectable viral load within 12 months of screening date.
  • Patient with a history of hypersensitivity to IVIg, other injectable forms of IVIg, or to glycine (used as an excipient).
  • Patient with known Immunoglobulin A (IgA) deficiency and antibodies against IgA.
  • Patients who are planning to receive the following treatments within the coming 12 months, or who have received in the stated timeframe before enrollment (Day 0)
  • Botulinum toxin within 6 months
  • Rituximab within 6 months
  • Steroid-sparing immunosuppressants (azathioprine, methotrexate, cyclophosphamide, or mycophenolate mofetil) within 1 month
  • Plasmapheresis within 3 months.
  • Prior chimeric antigen receptor (CAR)-T cell therapy or autologous hematopoietic stem-cell transplantation.
  • Received any blood, blood product, or blood derivative within 1 month of the baseline visit.
  • Had therapy with live attenuated virus vaccines within 3 months of the baseline visit.
  • Use of loop diuretics within 1 week of the baseline visit.
  • Patients at high-risk of thrombotic events such as deep vein thrombosis, cerebrovascular accident, pulmonary embolism, transient ischemic attacks, or myocardial infarction.
  • Uncontrolled hypertension (i.e., diastolic blood pressure [BP] > 100 mmHg and/or systolic BP > 160 mmHg). If a single measure exceeds this limit, a triple repeat measurement may be performed and the average of the three measurements used.
  • Congestive heart failure as per New York Heart Association III/IV, cardiomyopathy, cardiac arrhythmia associated with thromboembolic events (e.g., atrial fibrillation), unstable or advanced ischemic heart disease, hyperviscosity.
  • Patients with significant protein losing enteropathy, nephrotic syndrome, or lymphangiectasia.
  • Patients with hyperproteinemia, increased serum viscosity, and/or hyponatremia.
  • Severe liver or kidney disease (normal reference ranges of laboratory doing the analysis):
  • Alanine aminotransferase (ALT) or aspartate amino transferase (AST) >2.5x upper limit of normal (ULN)
  • Creatinine > 120 µmol/L
  • Blood urea nitrogen (BUN) > 2.5x ULN.
  • Signs of severe anemia: Hemoglobin of less than 7 g/dL, hemodynamically unstable due to active bleeding, and/or when evidence of end-organ ischemia secondary to severe anemia is present.
  • Body mass index > 35 kg/m2 or an IVIg dose that puts the patient at risk of fluid overload.
  • History of a malignant disease within 3 years of the baseline visit other than properly treated carcinoma in situ of the cervix or basal cell or squamous cell carcinoma of the skin.
  • Patients having participated in an interventional, investigational clinical study within 30 days of the baseline visit, or within 5 half-lives of the investigational medicinal product (IMP) under investigation.
  • Any condition that the Investigator believes is likely to interfere with evaluation of the IMP or with satisfactory conduct of the trial.

Study description and what participation involves

The study's detailed description, as published on ClinicalTrials.gov.

Detailed description from the registry

This is a phase III, double-blind, placebo-controlled, parallel group, multicenter study to assess the efficacy and safety of QIVIGY in adult participants with stiff person syndrome. Participants will be randomized in a 1:1 ratio, to receive either 2 g/kg of QIVIGY or equivalent volume of placebo. During the randomized phase, study treatment will be administered every 4 weeks for 24 weeks, at which point the primary efficacy endpoint assessment will be performed at an End of Randomized Treatment visit. At this study visit, all participants will be given the option to enter an open-label study extension. Participants who choose to continue in the study will receive 2.0 g/kg QIVIGY every 4 weeks, for a duration of 24 weeks.

AI summaryWhat participation may involve, in plain languageShow ▾Hide ▴

AI-written from the registry record, not the study's own wording. May contain errors or omissions. Check the registry text on this page and the original record ↗ before acting on it.

Participants are randomized 1:1 to receive either IVIg (2.0 g/kg) or placebo given by intravenous infusion over 2–5 days every 4 weeks for 24 weeks. At Week 24 there is an End of Randomized Treatment visit and participants may choose a 24‑week open‑label extension receiving IVIg every 4 weeks to Week 48. Visits include clinical assessments such as the Timed 25‑Foot Walk, stiffness and sensitivity scales, quality‑of‑life questionnaires, safety monitoring and routine blood tests; participants must keep a daily diary. Women of childbearing potential will have pregnancy tests and must use effective contraception while in the study.

How the study is structured. Adults with SPS are randomized 1:1 to receive either IVIg 10% (2.0 g/kg) or placebo, given intravenously over 2–5 days every 4 weeks for 24 weeks. The study is double-blind (participants, care providers, investigators, and outcome assessors are masked). After the randomized phase, participants may choose to join an open-label extension to receive IVIg every 4 weeks for an additional 24 weeks.

Questions you could ask

These questions are suggestions for a conversation with the study team or your own clinician, not advice.

  • The registry says recruitment has not started. When is it expected to open, and can I register interest now?
  • No sites are listed on the registry yet. Where will the study take place?
  • Which of the eligibility criteria would need to be checked with tests before I could join?

More on stiff person syndrome

Clinical trials8 trials listed for stiff person syndromeEvery trial the registry lists for stiff person syndrome, with recruitment status, phase and sites, updated from ClinicalTrials.gov.See all trials →Research updatesWhat changed in stiff person syndrome researchLatest monthly update: September 2026. Includes: Tube removal spasms. New research summarized each month in plain language, with links to every source paper.Read the latest update →

Important dates

Study start
September 2026 (estimated)
Primary completion
January 2028 (estimated)
Study completion
July 2028 (estimated)
Target enrollment
38 participants (estimated)
Last updated on registry
Sep 14, 2026
Data verified
Oct 10, 2026

Sponsor and research team

The lead sponsor funds and oversees the trial. A pharmaceutical or biotech company sponsor typically means the study is testing that company's drug or device; a hospital, university, or government agency usually indicates investigator-initiated or publicly funded research.

Lead sponsor
Kedrion S.p.A.

Central study contact

If you're interested in participating, the central contact can answer general questions about the study — including eligibility requirements and how to find a recruiting site near you. Actual eligibility is determined by the site's medical team.

Participating sites

Study locations have not been posted on ClinicalTrials.gov yet. This study is not yet recruiting, so sites may be added when recruitment begins. The central study contact above may be able to tell you about planned sites.

Terms used on this page · explanations by MedicalUpdates.ai

placebo
A treatment that looks like the study treatment but contains no active ingredient. Some participants receive it instead of the study treatment, usually without knowing which they got.
Informed Consent Form
The process of explaining a study, including its risks and what participation involves, so that a person can decide freely whether to take part. Consent is usually documented in writing, and a participant can choose to leave the study later.
enrolment
The number of participants a study plans to include, or has included. 'Estimated' means the planned number; 'actual' means the number who joined.
prior to screening
The checks done before enrolment to see whether a person qualifies, such as tests, scans or a review of medical history.
women of childbearing potential
Studies often ask participants who could become pregnant, or could father a child, to use contraception during the study and for a period afterwards, because the effect of the treatment on a pregnancy is unknown.
timeframe
The period over which an outcome is measured, for example 'at 12 weeks'. It is not necessarily the total length of the study.
immunosuppressants
A medicine that reduces the activity of the immune system. Studies of autoimmune conditions often require a stable dose, a prior failure, or a washout of such medicines.
chimeric antigen receptor
A treatment in which a person's own immune cells (T cells) are collected, modified in a laboratory to recognise a target, and returned to the body.
baseline
Measurements taken at the start of the study, before any study treatment, so that later results can be compared with them.
upper limit of normal
The highest value of a blood test that a laboratory considers normal. Criteria such as '≤ 3 × ULN' mean the result must be no more than three times that value.
investigational
A treatment that is being tested and has not been approved for this use. It may be approved for a different condition. Being studied does not mean it works or is available outside the study.
5 half-lives
The time it takes for the amount of a drug in the body to fall by half. 'Five half-lives' is often used as the point at which a previous drug has essentially left the body.
Inclusion Criteria
The conditions a person must meet to be considered for the study, for example a confirmed diagnosis, an age range or a test result.
Exclusion Criteria
The conditions that rule a person out even if they meet the inclusion criteria, for example other illnesses, certain medicines or pregnancy.
double-blind
Two types of people involved in the study do not know which intervention a participant is receiving. The ClinicalTrials.gov record specifies who is masked, for example participants, care providers, investigators or outcome assessors.
placebo-controlled
A study design in which one group receives a placebo so that the study treatment's effects can be compared with no active treatment.
parallel group
Participants are divided into two or more groups, and each group receives a different intervention at the same time, so the groups can be compared.
randomized
Participants are assigned to the study groups by chance, like a coin toss, rather than chosen by the doctor or the participant. This is done so the groups are comparable.
1:1
How many participants go to each group. In a 2:1 ratio, two are assigned to the first group for every one assigned to the second.
endpoint
Something the study measures to judge its results, such as a symptom score, a blood test or survival. Outcomes are grouped as primary, secondary and sometimes exploratory.
open-label
No masking is used, so the assigned intervention is not deliberately hidden from participants or study staff.

The study record on this page is reproduced from ClinicalTrials.gov, a database of the U.S. National Library of Medicine, where it was submitted by the study sponsor. MedicalUpdates.ai does not own this content, is not affiliated with or endorsed by ClinicalTrials.gov, NIH, or the U.S. Government, and does not verify the record. Plain-language notes, the glossary and the questions above are added by this site; text in the boxes marked "AI summary" was written by an AI model and may contain errors. Registry records change over time. Check the original record for the current version and discuss eligibility or participation with a qualified healthcare professional.

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