The pHeNIx study, a national multicentre prospective non-interventional study, should help to describe the conditions of use for Hizentra® and the methods for switching from the IV to SC route in everyday practice, together with the tolerability and efficacy of treatment, which is monitored using a patient application (PRO: Patient-Reported Outcomes).

Chronic Inflammatory Demyelinating Polyneuropathy (CIDP) is a neurological and rare type of autoimmune disorder. Intravenous immunoglobulin (IVIg) is the first-line treatment for CIDP which has been proven to be effective. For several years, published cases have suggested that the Sub-Cutaneous Ig (SCIg) may be an alternative treatment to IVIg in the treatment of CIDP. Compared to IVIg treatment, the SCIg can achieve more stable plasma IgG concentrations, suggesting a potential reduction in the dose exhaustion effect at the end of the cycle, but also fewer systemic effects. SC administration also enables more straightforward treatment to be given for ambulatory patients.

Based on the PATH study (NCT01545076), a double blind placebo-controlled, randomised, prospective, international multicentre phase III study, Hizentra® obtained an extension of its marketing authorization for the CIDP indication as maintenance treatment after stabilisation with IVIg.

However, in the "real-life" situation, the literature is still based at present on small series of patient or short-term follow-up periods.

However, the methods for switching from the IV to the SC route and the characteristics of patients receiving this treatment are not known. In addition, SCIg administration remote from a specialist centre without assistance from a health professional no longer enables a more regular assessment of the patient in terms of tolerability and efficacy.

The pHeNIx study, a national multicentre prospective non-interventional study, should help to describe the conditions of use for Hizentra® and the methods for switching from the IV to SC route in everyday practice, together with the tolerability and efficacy of treatment, which is monitored using a patient application (PRO: Patient-Reported Outcomes). The study duration is estimated to be 36 months in view of: a 24-month inclusion period and a 12-month follow-up period.

Inclusion Criteria:

• Adult patient (aged ≥18 years)
• Patients suffering from CIDP according to EAN/PNS 2021 criteria
• Planned switch from IVIg to Hizentra®
• Patient treated with at least 3 courses of IV immunoglobulin and deemed by the investigator to be dependent on immunoglobulins
• Patient deemed to be stable, with no change in their treatment for the disease during the 3 months prior to inclusion
• Patients who have a smartphone, a tablet or a computer
• Patients who have been informed verbally and in writing of the purposes of the study

Exclusion Criteria:

• Concomitant participation in an interventional clinical study

French cohort of patients with CIDP