A Proof of Concept Study With Rituximab in Patients With CIDP Not Responding to Conventional Immune Therapy

Chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) is a chronic and often disabling neuropathy that often responds to immune therapies. A few phenotypes have been identified even if it is unclear whether they are variants of CIDP or different diseases considering their relatively different responses to therapy. Antibodies against proteins at the node of Ranvier, including contactin 1 and neurofascin 155, have been reported in up to 10% of the patients and were associated to a poor response to CIDP therapy but a positive response to Rituximab supporting the heterogeneity of CIDP. We will examine these antibodies in a large population of Italian CIDP patients included in a Database and correlate their presence with the clinical and electrophysiological features of the neuropathy, its progression and response to therapy. We will perform an open label prospective therapeutic study with Rituximab in patients with CIDP not responsive to conventional immune therapies and will correlate the response to therapy to the clinical phenotype and the presence of anti-neural antibodies.This may lead to a more appropriate choice of therapy in CIDP avoiding the use of expensive and possibly ineffective therapy. We will also collect the biological samples (serum and when available CSF) of the patients with CIDP and store them to allow the formation of a biological bank that may be used in future immunological studies to clarify the pathogenesis a of the disease and possibly to identify biomarkers of the disease and of response to therapy. This study will permit to collect a sufficiently large number of adequately and homogeneously examined patients with CIDP, with different antibody reactivities and with unsatisfactory response to therapy. This will permit to have sufficiently large number of patients to perform an open-label study with Rituximab whose efficacy has been so far reported only in anecdotal reports on small number of patients.