P0206RITUXIMAB IN ADULT ONSET OF IGA VASCULITIS WITH SEVERE RENAL INVOLVEMENT: A SINGLE CENTER EXPERIENCE
Authors: Fenoglio Roberta , Cozzi Martina , Sciascia Savino , De Simone Emanuele , Del Vecchio Giulio , Ferro Michela , Quattrocchio Giacomo , Naretto Carla , Caputo Giorgia , Careddu Andrea , Roccatello Dario 
Published: June 2020

Abstract

Background and Aims
IgA-vasculitis (IgAV) is a systemic small vessels vasculitis characterized by deposition of underglycosylated IgA1 immune complexes. Renal involvement indicates severity of illness and chronic kidney disease represents the most serious long-term complication of IgAV. Presently, no treatment is specifically recommended in IgAV Glucocorticoids (GC) have been traditionally thought to be effective in tempering systemic symptoms, but did not show long-term benefits either in reducing flares or progression of kidney disease. The effectiveness of conventional immunosuppressants is controversial. Recently Rituximab (RTX) has been proved to be effective in a few case series of adults with IgAV. However, long term results are lacking. Aim of the study: to evaluate the effectiveness of RTX as first line therapy in induction and maintenance of remission of adults with IgAV with biopsy-proven crescentic glomerulonephritis.

Method
We reviewed the clinical records of patients with adult-onset IgAV treated with RTX at our Center. Patients included 8 males and 4 females, mean age 45 years (range 19-75) with mean follow-up duration of 31 months (range 6-144). Diagnosis was based on the combination of clinical assessment, serological tests and histological analysis according to EULAR criteria. All patients (pts) had a biopsy proven IgAV- severe nephritis. RTX was given for the treatment of relapsing or refractory disease or because of definite contraindications to standard dose CS and/or conventional immunosuppressants. Patients received 4 weekly doses of RTX (375 mg/m2) given alone (8 pts) or in combination with CS (4 pts). Disease activity was evaluated by Birmingham Vasculitis Activity Score version 3 at the onset and at 1, 6 and 12 months and at the end of follow up. Complete remission (CR) was defined as BVAS of 0

Results
Eleven pts (91.7%) achieved a clinical response at 6 months. Ten pts had a CR while 1 pt had a partial response and was given an additional dose of RTX after 12 months from induction due to persistent proteinuria (1gr/24 hrs), despite systemic remission. He achieved a CR 6 months later. One patient did not respond to RTX and was switched to MMF. Among the 10 pts with CR, 1 patient needed maintenance doses of RTX every 6 months due to relapse of palpable purpura; 1 relapsed after 15 months and received a new induction course showing a CR again.
Significant decrease in 24-hour proteinuria (P = 0.043), BVAS (P = 0.031),and CRP level from RTX initiation through the last follow-up visit was detected. RTX was generally well tolerated. One patient, who had a CR with RTX alone died after 6 months of follow-up for cardiovascular cause.

Conclusion
This extended experience confirms our initial results supporting the use of RTX in the treatment of IgAV with severe renal involvement. Indeed, RTX proved to be effective and safe for induction and maintenance of long-lasting remission. Present data also suggest that RTX is not only effective for severe and refractory IgAV, but can be also proposed as a first line therapy.