Flare of a mixed cryoglobulinaemic vasculitis after obinutuzumab infusion

• Published in: Clinical and Experimental Rheumatology 2021-01, Vol.39 Suppl 129 (2), p.52-55
• Main Authors: Martin de Fremont, Gregoire, Chiron, Andrada, Krzysiek, Roman, Hacein-Bey-Abina, Salima, Mariette, Xavier, Nocturne, Gaetane
• Format: Article
• Language: English
• Subjects: Antibodies, Monoclonal, Humanized - adverse effects; Cryoglobulinemia; Female; Humans; Immunology; Life Sciences; Rituximab - adverse effects; Vasculitis - chemically induced; Vasculitis - drug therapy
• ISSN: 0392-856X; 1661-6596; 1593-098X; 1422-0067
• DOI: 10.55563/clinexprheumatol/rit83o

Obinutuzumab (OBZ) is a new humanised type II anti-CD20 monoclonal antibody (mAb) approved in onco-haematology. Its use as an alternative to rituximab (RTX) in case of immunisation in autoimmune diseases has not been fully assessed yet. Here we report the case of a patient suffering from a refractory cryoglobulinaemic vasculitis (CV) associated to Sjögren's syndrome (SS) and treated with OBZ. Since the patient was immunised against RTX, she was treated with OBZ at relapse. Three days after the infusion of OBZ, she presented a vasculitis flare. Rheumatoid factor level, complement level and cryoprecipitation were evaluated on consecutive serum samples of the patients and after RTX and OBZ addition in vitro. No evidence for cross-reactivity between anti-RTX Abs and OBZ was found. However, we could observe in vitro that cryoprecipitation was worsened by the simultaneous presence of anti-RTX Abs and RTX. We suggest that the flare of CV after OBZ infusion could be linked to a large release of immune complexes following B cells lysis induced by OBZ. Based on our report, we think that the use of OBZ needs to be carefully discussed in patients with mixed CV.