P117 Rituximab for IgG4-related disease: the Newcastle experience

Background IgG4-related disease (IgG4-RD) is a multisystem immune mediated fibro-inflammatory condition characterised by the three histopathologic features of IgG4-RD lymphoplasmacytic infiltration, storiform fibrosis and obliterative phlebitis. The condition can be indolent with few symptoms or present with organ or life-threatening disease. First-line treatment with high dose corticosteroids is often effective, however when tapering steroids, the disease can relapse, and second line agents such as methotrexate (MTX), azathioprine (AZA) or mycophenolate (MMF) are not always effective or tolerated. In 2016, following evidence from observational studies, NHS England approved the use of rituximab (RTX) in refractory IgG4-RD according to strict criteria. In our unit we have used rituximab, with or without cyclophosphamide induction, in eight patients with IgG4-RD. Our aim was to assess effectiveness of rituximab treatment and adherence to NHS England guidelines. Methods Using our connective tissue disease database, patients with IgG4-RD were identified and their electronic notes were reviewed. Outcome after rituximab treatment was assessed by the evaluation of clinical and radiological responses. Results Between August 2017 and September 2019, 15 patients with IgG4-RD were seen in the rheumatology service. 8 patients went on to receive rituximab therapy, 4 with IV cyclophosphamide (CYP). 5/8 patients had head and neck disease and 3/8 had abdominal disease (pancreas, retroperitoneal, renal). By comparison, those patients that did not receive rituximab had a preponderance of abdominal disease (4/7 had abdominal disease, 2/7 head and neck, 1/7 breast). 8/8 patients receiving rituximab were discussed in a designated MDT and met NHS diagnostic guidelines. MDT treatment decisions were made based on ‘refractory’ or ‘organ critical’ disease criteria. In all patients, with available post treatment imaging, radiological response was demonstrated. In one case, imaging showed improvement in some areas and progression in other areas and response was described as ‘partial’. Conclusion In the patients treated to date in our unit, rituximab has been shown to be an effective treatment for IgG4-RD. Cyclophosphamide induction has been used in a subset of patients. Patients with head and neck disease were more likely to require escalation to rituximab therapy, compared with those with abdominal disease. Disclosures F. Rayner None. B. Griffiths None. M. Nayar None. K. Oppong None. J. Vila None.