#5882 benefit of long-term tolvaptan administration on kidney disease progression in autosomal dominant polycystic kidney disease: a single-centre experience

Abstract Background and Aims Tolvaptan introduction in autosomal dominant polycystic kidney disease (ADPKD) treatment has significantly modified kidney disease progression in these patients. The efficacy and safety of tolvaptan in the management of ADPKD has already been demonstrated by TEMPO and REPRISE trials, however studies examining the long-term outcomes are limited. The aim of our study was to evaluate the long-term administration of tolvaptan in patients with ADPKD in our center. Method ADPKD patients treated with tolvaptan for at least one year were included in the study. Demographic, laboratory, and total kidney volume (TKV) data were collected. Kidney disease progression was assessed by comparing observed and predicted glomerular filtration rate (eGFR), based on the Mayo Clinic prediction model, at the last visit. Results Forty-one patients, 22 males, with ADPKD were studied. Median age at initial visit was 35 years (IQR 27-42), and median time on tolvaptan treatment was 24 months (IQR 18-33). Six (14.6%) patients discontinued tolvaptan after at least one year on treatment. Patients were classified according to the Mayo Clinic imaging classification into 1C (n = 8), 1D (n = 16) and 1E (n = 17). Those who received tolvaptan showed a lower eGFR decline from baseline compared to predicted (eGFR 66.7±32.7 vs 61.5±29.1, p<0.001), while a greater benefit was observed in Class 1E (eGFR 60.1±36.5 vs 52.4±29.5, p = 0.003) and in patients with eGFR>45ml/min (eGFR 79.4±28.8 vs 73±25.2, p = 0.001). Conclusion Our initial experience from long-term administration of tolvaptan in patients with ADPKD demonstrates benefit on kidney disease progression. The widespread use of tolvaptan in a larger number of patients and their long-term follow up are necessary to draw more secure conclusions.