Pos1152 attainment of eular/era-edta treatment targets in the first year in lupus nephritis: a multicenter observational study

Background The approval of two new drugs, belimumab and voclosporin, in lupus nephritis (LN) over the last years has raised questions regarding their place in the therapeutic algorithm of LN. Their use in initial regimens or in refractory/relapsed disease depends on disease outcomes with current standard of care (SoC) therapies. Objectives To calculate EULAR/ERA-EDTA renal response rates with SoC therapies at 3, 6 and 12 months, as well as rates of successful tapering to the recommended glucocorticoid use at 6 months in real-life clinical settings. Methods Combined retrospective and prospective (2015-today) cohort study of patients with histologically confirmed LN. Demographic, clinical, and laboratory data, as well as treatment administered at baseline and respective changes every 3 months, were collected. Renal response rates according to EULAR/ERA-EDTA goals of treatment were calculated: (at 3 months: proteinuria reduction by 25%, 6 months: 50% reduction to subnephrotic level, 12 months: proteinuria< 500-700mg/24h, all with stabilization or improvement in kidney function). The percentage of patients who received IV methylprednisolone (total recommended dose 500-2500mg), as well as mean prednisone dose per day at baseline (recommended dose 0.3-0.5mg/kg in class III and class IV and 20mg in class V) and thereafter (<7.5mg/day at 6 months in class III and class IV and <5mg/day at 3 months in class V). We also calculated the percentage of patients who had tapered prednisone to the recommended daily dose by 6 months. Results 110 patients were included, 83 completed a 12month follow up [81.8% female, median (IQR) age 36.5 (23) years]. One third (33.6%) of patients had nephrotic range proteinuria at diagnosis. Histologically, 16.7% had LN class III, 33.3% class IV, 18.5% class V and 27.8% mixed class (III/IV +V). With SoC therapy [initial therapy: 48.1% cyclophosphamide (CYC), 32.4% mycophenolic acid (MPA), followed by maintenance therapy], 76.7%, 82.6% and 71.1% achieved EULAR/ERA-EDTA renal response rates at 3, 6 and 12 months, respectively. No differences between CYC and MPA groups regarding response rates were noted. All patients received IV methylprednisolone at baseline [median (IQR) 2.0 (3.0) gr]. Regarding glucocorticoid use, in proliferative classes (III/IV), median (IQR) prednisone starting dose was 40.0 (20.0) mg/day, corresponding to a mean (SD) dose of 0.63 (0.27) mg/kg/day. At 6 months, median (IQR) daily dose was 10.0 (10.0) mg. In class V LN, median (IQR) daily starting dose was 32.5 (20.0) mg and 15.0 (10.0) mg at 3 months. Conclusion Although a significant number of LN patients achieve treatment target between 3-12 months, approximately 25-30% fail. Moreover, prednisone doses used in LN tend to be higher than those recommended by EULAR/ERA-EDTA. Predictive factors associated with suboptimal response can help to shape therapeutic decisions identify patients that may benefit from early use of novel therapies. Reference [1]Fanouriakis A, et al. 2019 Update of the Joint European League Against Rheumatism and European Renal Association-European Dialysis and Transplant Association (EULAR/ERA-EDTA) recommendations for the management of lupus nephritis. Ann Rheum Dis 2020;79(6):713-723. Acknowledgements: NIL. Disclosure of Interests None Declared.