IVIg Treatment-Related Fluctuations in CIDP Patients Using Daily Grip Strength Measurements

This is a prospective observational study of 30 adult CIDP patients who receive home IVIg infusion services from AxelaCare Health Solutions, LLC. The decision to treat with IVIg will be entirely at the discretion of the patient's treating physician.

Subjects will be recruited by individual site investigators. Prior to enrollment each potential subject will have their screening data reviewed by a panel of medical experts for confirmation of inclusion criteria. Each reviewer will be an independent, board-certified, practicing and experienced neurologist with a special interest in CIDP.

Enrolled subjects who have provided informed consent will be instructed to perform and document daily Jamar hand-held Dynamometer grip strength measurements in a paper diary for a 6 month time frame.

Weekly nursing visits will capture disability assessments, physical tests, adverse event and concomitant medications assessment, and other clinical changes that may affect grip strength measurements. Nurses will review each subjects captured grip data from paper diary on an iPad during weekly home assessments. Nurses will also administer the HRQOL Short-Form (SF) 36 questionnaire at the baseline, week 12 and week 24 study visits.

Serum immunoglobulin G (IgG) levels will be captured by the home study nurse at three time points surrounding IVIg infusions and will be classified as either trough, peak, or mid. Each subject will have serum Ig collected by blood draw for the first 4 IVIg treatment cycles, for a total of 12 blood draws per subject.

The "trough" serum IgG level will be collected immediately prior to Ig infusion. The "peak" serum IgG level will be collected 5 minutes post-Ig infusion. The "mid" serum IgG level will be collected two weeks post-Ig infusion.

There are currently no known biomarkers that can assist with CIDP diagnosis, prognosis, or treatment optimization. As part of this study, subjects will be required to have additional blood taken and stored for future use. Future use may include the possible discovery of specific biomarkers predicting the response to IVIg or other therapies, optimization of IVIg dosage based on pharmacodynamics, pathogenesis of CIDP, and more effective CIDP diagnostic markers. Blood taken for future use will be obtained with each serum IgG sample. No additional blood draws will be required.

Should IVIg therapy be discontinued during the study, daily grip strength measurements will continue to be performed and recorded in the subject diary for up to 30 days or to the end of the study, whichever comes first. Weekly nurse visits with collection of the disability assessments and serum IgG blood draws will continue for up to 4 home nurse visits or until the end of the study, whichever comes first.

Eligibility Criteria:
Inclusion Criteria:

1. Definite or probable CIDP according to the European Federation of Neurological Studies (ENFS)/Peripheral Nerve Society (PNS) criteria 2010
2. Inflammatory Neuropathy Cause and Treatment Group (INCAT) upper limb disability score of 2 or greater at any time during disease
3. CIDP Disease Activity Status (CDAS) classification of Stable Active Disease or Improvement at time of screening
4. Men or women age 18-85 years
5. Receiving physician prescribed intravenous immunoglobulin (IVIg) therapy with a treatment interval between a minimum of 21 days and a maximum of 42 days
6. Be on a stable dose of IVIg for at least 3 months prior to study participation
7. With proper training from a healthcare professional, demonstrate proficiency in the ability to perform daily Jamar Dynamometer grip strength measurements
8. Ability to have an adult present (e.g., spouse, adult child) to assist with daily Dynamometer grip strength measurement, if needed
9. Eligible for infusion services by AxelaCare Health Solutions, LLC, in collaboration with the subject's prescribing physician and insurance provider
10. Ability to read and write English
11. Ability and willingness to provide informed consent and comply with study requirements and procedures
12. Confirmation of diagnosis of CIDP by outside expert panel

Exclusion Criteria:

1. Any polyneuropathy of other causes, including multifocal motor neuropathy, hereditary demyelinating neuropathy, POEMS syndrome, polyneuropathy associated with diabetes mellitus, polyneuropathy associated with systemic lupus erythematosus
2. Subjects who, by majority vote of the outside expert panel do not meet diagnostic criteria for CIDP or probably CIDP
3. CDAS classification of Cure, Remission, or Unstable Active Disease
4. The presence of any type of recent arm and/or hand bone fracture
5. The presence of any medical condition that the investigator and/or prescribing physician deems incompatible with participation in this trial
6. Receiving subcutaneous immunoglobulin (SCIg) therapy during study participation
7. Receiving pulse dose corticosteroids during study participation (daily corticosteroids are allowed provided dose equal or less than prednisone 20 mg daily and no anticipated dose changes during the study)
8. Prisoners
9. Ward of the state