Subcutaneous Immunoglobulin Therapy Effectiveness Monitoring in CIDP Patients Using Smart Devices (STEPS)

Chronic inflammatory demyelinating polyneuropathy (CIDP) is a rare autoimmune disease that affects the peripheral nerves. It causes progressive weakness and sensory loss in the arms and legs, which can severely limit daily activities. Many patients need long-term treatment with immunoglobulins, either through intravenous infusions (IVIG) or subcutaneous injections (fSCIG).

The S.T.E.P.S. study aims to explore how digital health technologies-specifically smartwatches-can help monitor the disease course and treatment effects in CIDP patients who use fSCIG at home. Current clinical tests are useful but sometimes miss small changes in strength or function. Wearables may provide a more detailed and continuous picture of patients' health between clinic visits.

Study Goals:

The main goal is to find out whether smartwatch data (such as step count and physical activity) reflect disease severity and treatment response when compared to standard clinical scores like the Inflammatory Neuropathy Cause and Treatment (INCAT) scale and the Inflammatory Rasch-built Overall Disability Scale (I-RODS).

Secondary goals include:

Assessing how smartwatch data relate to patients' quality of life and sleep patterns.

Comparing smartwatch results with other clinical scores such as muscle strength (MRC sum score) and grip strength.

Evaluating how well patients can use the smartwatch over the long term during home treatment.

An additional exploratory goal is to see whether smartwatch data can detect early signs of worsening disease before symptoms appear.

Study Design:

This is a 12-month observational study with five main clinic visits (at 0, 3, 6, 9, and 12 months). After enrolling, participants will begin or continue subcutaneous immunoglobulin therapy as decided by their treating physician. Each visit includes standard clinical assessments and questionnaires.

Participants will receive a smartwatch at the start of the study to continuously track their activity and sleep patterns. A follow-up phone call one week later will check that the device is working properly.

Duration:

Recruitment will last about 6 months, and each participant will be followed for 12 months.

Why This Matters:

By combining established clinical measures with continuous digital monitoring, the S.T.E.P.S. study may help improve understanding of disease activity and treatment response in CIDP. This could lead to more personalized therapy schedules and better long-term care for patients.

Study Overview

• Status: Recruiting
• Conditions: CIDP - Chronic Inflammatory Demyelinating Polyneuropathy

• Study Type: Observational
• Enrollment (Estimated): 35

Contacts and Locations

• Study Contact: Name: Marc G Pawlitzki, PD Dr. med.; Phone Number: +49 02118117887; Email: neuro-trials@med.uni-duesseldorf.de

Study Locations

• Germany
  • North Rhine-Westphalia
    • Düsseldorf, North Rhine-Westphalia, Germany, 40225
      • Recruiting
      • University Hospital Düsseldorf
      • Contact: Marc G Pawlitzki, PD Dr. med.; Phone Number: +49 02118117887; Email: neuro-trials@med.uni-duesseldorf.de
    • Münster, North Rhine-Westphalia, Germany, 48149
      • Not yet recruiting
      • University Hospital Münster
      • Contact: Matthias Schilling, Prof. Dr. med.; Phone Number: +49 251 83-48199; Email: matthias.schilling@-ukmuenster.-de

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

CIDP adult patients (≥18 years) with typical or possible typical CIDP (2021 EAN/PNS criteria), switched from IVIG to fSCIG within 6 months or during recruitment

Description

Inclusion Criteria:

• Diagnosed typical or possible typical CIDP according to the 2021 EAN/PNS criteria
• Age ≥18 years
• Ability to use a smartwatch as decided by the investigator
• switched from IVIG to fSCIG within the prior 6 months or plan to switch during study recruitment phase
• on investigator-confirmed stable IVIG therapy pre-switch

Exclusion Criteria:

• Age < 18 years
• Inability to operate smartwatch or smartphone device
• current pregnancy and breastfeeding status
• CIDP variants according to the 2021 EAN/PNS criteria

Study Plan

How is the study designed?

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
CIDP patients; CIDP patients (≥18 years) with typical or possible typical CIDP (2021 EAN/PNS criteria), Switched from IVIG to fSCIG within 6 months or during recruitment, Must be able to use smartwatch + smartphone, Exclude: CIDP variants, pregnancy, breastfeeding, inability to use devices

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Inflammatory Rasch-built Overall Disability Scale (I-RODS)	24-item scale, with each item representing a common, daily activity minimum value: 0 points, maximum value: 48 points, best result: 48 points	Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Inflammatory Neuropathy Cause and Treatment (INCAT) disability score	minimum value: 0 points, maximum value: 10 points, best result: 0 points	Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Longitudinal development of activity parameter: step count		365 days
Longitudinal development of activity parameter: duration of moderate activity (seconds) defined by Withings	Examples for moderate activity: Walking fast, Cleaning (vacuuming, washing windows, etc.), Playing doubles tennis or badminton, Taking a bike ride, Gardening	365 days

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Grip strength	Measured via Vigorimeter in kPa	Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Medical Research Council (MRC)-Sumscore	minimum value: 0 points, maximum value: 60 points, best result: 60 points	Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Longitudinal development of activity parameter: approximate distance traveled (meter)		365 days
Longitudinal development of activity parameter: duration of soft activity (seconds) defined by Withings	Examples for soft activity: Sleeping, Sitting quietly, Walking slowly, Typing on a computer keyboard while seated, Watching television, Doing the dishes	365 days
Longitudinal development of activity parameter: duration of intense activity (seconds) defined by Withings	Examples for intense activity: Hiking, Running, Carrying heavy loads, Riding a bike, Playing football,baseball, or tennis (singles), Playing jump rope	365 days
Longitudinal development of activity parameter: sum of all active time (seconds)		365 days
Wearing time of smartwatch (daily)		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Longitudinal development of activity parameter: approximate calories burned		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Subjective occurrence of end-of-dose phenomena/wearing off		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Quality of life (QoL)	The Quality of Life Questionnaire (QoL) is an instrument for measuring patients' subjective quality of life in a wide range of specific areas, WHOQOL-BREF (World Health Organization Quality of Life - abbreviated version)	Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Pittsburgh Sleep Quality Index (PSQI)		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Change in Blood analysis (levels of sNfl, serum proteomics)		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)
Questionnaire about smartwatch usage		End of study visit (after 12 months, V5)
Longitudinal development of sleep parameter: time awake (seconds)		365 days
Longitudinal development of sleep parameter: number of times user woke up		365 days
Longitudinal development of sleep parameter: time to sleep (seconds)		365 days
Longitudinal development of sleep parameter: total time in bed (seconds)		365 days
Longitudinal development of sleep parameter: total time asleep (seconds)		365 days
Longitudinal development of sleep parameter: WASO	Wake after sleep onset (WASO): total time asleep divided by total time in bed	365 days
Longitudinal development of sleep parameter: time spent in bed before falling asleep (seconds)		365 days
Longitudinal development of sleep parameter: time awake after first falling asleep (seconds)		365 days
Longitudinal development of sleep parameter: Withings Sleep score	Defined by Withings as follows: It measures every night's sleep and provides a score out of 100 points based on 4 key inputs: Duration (total time spent sleeping); Depth (part of night spent in restorative phases and deep sleep); Regularity (consistency between your bed- and rise-times); Interruptions (time spent awake)	365 days
Longitudinal development of cardiovascular parameter: average heartrate		365 days
Longitudinal development of cardiovascular parameter: maximal heartrate		365 days
Longitudinal development of cardiovascular parameter: minimum heartrate		365
Longitudinal development of cardiovascular parameter: time in light heartrate zone (seconds)	Light heartrate zone is defined by Withings as follows: from 0% inclusive to 50% exclusive of maximum heart rate.	365 days
Longitudinal development of cardiovascular parameter: time in moderate heartrate zone (seconds)	Moderate heartrate zone is defined by Withings as follows: from 50% included to 70% excluded of maximal heart rate.	365 days
Longitudinal development of cardiovascular parameter: time in intense heartrate zone (seconds)	Intense heartrate zone is defined by Withings as follows: from 70% included to 90% excluded of maximal heart rate.	365 days
Longitudinal development of cardiovascular parameter: time in maximal heartrate zone (seconds)	Maximal heartrate zone is defined by Withings as follows: from 90% included to 100% included of maximal heart rate.	365 days
Number and time of Irregular 1-channel ECGs (according to Withings algorithm)		365 days
Change in Fatigue Severity Scale (FSS)		Baseline up to 12 months, 5 visits (months 0, 3, 6, 9, and 12)

Collaborators and Investigators

• Sponsor: Heinrich-Heine University, Duesseldorf
• Investigators: Principal Investigator: Marc G Pawlitzki, PD Dr. med., Department of Neurology, Heinrich-Heine University, and University Hospital Duesseldorf, Germany

Publications and helpful links

General Publications

• Masanneck L, Voth J, Gmahl N, Jendretzky K, Huntemann N, Werner NM, Schmidt L, Oeztuerk M, Quint P, Schroeter CB, Hartung HP, Skripuletz T, Meyer Zu Horste G, Ruck T, Meuth SG, Pawlitzki M. Digital Activity Markers in Chronic Inflammatory Demyelinating Polyneuropathy. Ann Clin Transl Neurol. 2025 Oct;12(10):2045-2055. doi: 10.1002/acn3.70137. Epub 2025 Jul 9.

Study record dates

Study Major Dates

• Study Start (Actual): January 15, 2026
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): January 1, 2028

Study Registration Dates

• First Submitted: November 27, 2025
• First Submitted That Met QC Criteria: November 27, 2025
• First Posted (Actual): December 10, 2025

Study Record Updates

• Last Update Posted (Actual): March 11, 2026
• Last Update Submitted That Met QC Criteria: March 9, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Keywords: sleep; wearable; SCIG; IVIG; steps; CIDP; DHT
• Additional Relevant MeSH Terms: Nervous System Diseases; Pathologic Processes; Neuromuscular Diseases; Chronic Disease; Disease Attributes; Autoimmune Diseases; Immune System Diseases; Peripheral Nervous System Diseases; Autoimmune Diseases of the Nervous System; Demyelinating Diseases; Polyneuropathies; Polyradiculoneuropathy; Pathological Conditions, Signs and Symptoms; Polyradiculoneuropathy, Chronic Inflammatory Demyelinating
• Other Study ID Numbers: STEPS_1.0

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No