Telitacicept for Refractory Chronic Inflammatory Demyelinating Polyneuropathy

Inclusion Criteria: (1) Male or female participants aged 18 to 65 years, inclusive.

(2) Diagnosis of refractory chronic inflammatory demyelinating polyneuropathy (CIDP). Refractory CIDP is defined as the absence of evidence of clinical improvement (ECI) after at least 1 month of at least one first-line therapy, including intravenous immunoglobulin, corticosteroids, or plasma exchange, or a persistently elevated INCAT disability score of ≥2. ECI is defined as meeting at least one of the following criteria: a. A decrease of ≥1 point in the adjusted INCAT disability score; b. An increase of ≥4 points in the I-RODS total score; c. An increase of ≥3 points in the MRC sum score; d. An improvement of ≥8 kPa in grip strength. (3) INCAT disability score of 2 to 9. (4) Able to fully understand the study, willing to comply with study procedures, and able to provide written informed consent.

Exclusion Criteria:

1. Progressive neurological disease unrelated to CIDP.
2. Limb numbness or weakness caused by other etiologies, including but not limited to hereditary demyelinating neuropathy, neuropathy secondary to infection or systemic disease, diabetic neuropathy, drug- or toxin-induced neuropathy, multifocal motor neuropathy, polyneuropathy associated with IgM monoclonal gammopathy, POEMS syndrome, cerebral infarction, acute myelitis, multiple sclerosis, neuromyelitis optica spectrum disorder, or other conditions that may cause limb numbness or muscle weakness.
3. Active hepatitis or severe hepatic dysfunction, defined as liver function test values greater than two times the upper limit of normal. Participants who are positive for hepatitis B surface antigen (HBsAg) will be excluded. Participants who are positive only for hepatitis B core antibody (HBc-Ab) must undergo quantitative HBV-DNA testing and will not be excluded if the result is negative.
4. Severe renal impairment, including acute kidney injury or chronic kidney disease, or serum creatinine clearance <60 mL/min calculated using the Cockcroft-Gault equation.
5. Current pregnancy, breastfeeding, or planned pregnancy within 48 weeks.
6. Participation in another interventional clinical trial within 28 days before enrollment or within five half-lives of the investigational drug, whichever is longer.
7. History of splenectomy.
8. History of allergic reactions to contrast agents or intravenously administered human-derived biological products.
9. Severe psychiatric symptoms that preclude cooperation with study procedures.
10. Treatment with B-cell-depleting agents, such as rituximab, within 6 months before enrollment, or failure of B-cell counts to recover to the normal range, whichever is longer.
11. Active tuberculosis.
12. Diabetes mellitus.
13. Failure to complete serum ganglioside antibody testing to exclude other diseases.
14. Any other condition that, in the investigator's judgment, makes the participant unsuitable for the study.