An observational study in Sporadic Inclusion Body Myositis and Inclusion Body Myositis, sponsored by University of California, Irvine. Active, not recruiting at 13 sites in United States. Open to participants aged 40 Years and older. Per ClinicalTrials.gov, last updated 2026-05-27.
Sponsored by University of California, Irvine · Observational
This is a prospective natural history study on patients with clinically defined sIBM. Participants will be assessed every 6 months over two years (five visits total). We will include 150 participants, enrolled across 13 sites, with sporadic IBM, diagnosed according to established criteria.
This is a prospective natural history study on patients with clinically defined sIBM. Participants will be assessed every 6 months over two years (five visits total). We will include 150 participants with sporadic IBM, diagnosed according to established criteria. Participants will require an routine serum sample via blood draw to evaluate for NT5c1A antibody status. This testing will be performed at Washington University School of Medicine in the Neuromuscular Laboratory. Investigators will be blinded to antibody status. A subset of participants (40) will undergo a muscle biopsy at the Baseline visit.
Aim 1. To determine for the first time whether NT5c1A antibodies mediate disease progression over a two-year interval in patients with sIBM.
We will perform a prospective, non-interventional, observational study on patients with sIBM with follow up and evaluations every 6 months over a two-year time frame. Primary analyses are: 1) the rates of disease progression and severity as measured by rates of decline in IBM Functional Rating Scale (IBMFRS) score and Timed Get Up and Go (TUG); 2) the presence or absence of serum antibodies to NT5c1A; and 3) the presence and frequency of variant T-cells in the serum and skeletal muscle.
Aim 2. To perform a detailed morphological, histochemical and immunohistochemical analysis of fresh muscle biopsy specimens obtained from a subset of patients with sIBM.
Aim 3. To characterize the distribution of "immunosenescent" lymphocytes in circulating blood from patients with sIBM.
Aim 4. To quantify the decline in the respiratory function of sIBM patients.
49 studies on the registry are indexed under Myositis, Inclusion Body; 11 are open to participants now.
This study's enrollment of 150 is above the median of 80 across 17 observational studies indexed under Myositis, Inclusion Body.
Browse Myositis, Inclusion Body studies →University of California, Irvine is the lead sponsor of 466 studies on the registry; 96 are open to participants now.
Of its 41 completed or terminated interventional studies of FDA-regulated products, 30 (73%) have results posted.
Counted across the registry records on this site, refreshed daily.
Paticipants age 40 and older with sporadic IBM, diagnosed according to established criteria.
Exclusion Criteria:
Inclusion Body Myositis Functional Rating Scale (IBMFRS)
The IBMFRS is a 10 item questionnaire. Scores for each item range from 0 to 4. There is a total maximum score of 40 and minimum score of 0. The higher the score the better functional status of the person.
Time frame: Change from Baseline to Month 24
Timed Up and Go (TUG)
Stand up from a chair, walk 3 meters, sit back down in chair
Time frame: Change from Baseline to Month 24
Frequency of immunophenotypic abnormalities in blood and muscle
Laboratory assessment
Time frame: Change from Baseline to Month 24
Forced Vital Capacity (FVC) (sitting)
breathing test
Time frame: Change from Baseline to Month 24
Manual Muscle Testing
muscle strength testing
Time frame: Change from Baseline to Month 24
Hand Held Dynamometry
muscle strength testing
Time frame: Change from Baseline to Month 24
Sydney Swallow Questionnaire
swallow ability questionnaire
Time frame: Change from Baseline to Month 24
EAT-10 Questionnaire
swallow ability questionnaire
Time frame: Change from Baseline to Month 24
NIH PROMIS questionnaires
quality of life questionnaires
Time frame: Change from Baseline to Month 24
Forced Vital Capacity (supine)
breathing test done while lying down
Time frame: Change from Baseline to Month 24
Maximum Inspiratory Pressure/Maximum Expiratory Pressure
breathing tests
Time frame: Change from Baseline to Month 24
sporadic inclusion body myositis physical functioning assessment (sIFA)
functional ability questionnaire
Time frame: Change from Baseline to Month 24
Plan to share: Undecided
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in May 2026. You cannot join it, but the record below documents what was studied.
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University of California, Irvine