IntroductionLarge-scale trials showed positive outcomes of sodium–glucose cotransporter-2 inhibitors (SGLT2i) in adults with chronic kidney disease (CKD). Whether the use of SGLT2i is safe and effective in patients with the common hereditary CKD Alport syndrome has not yet been investigated specifically in larger cohorts. MethodsThis observational, multi-center, international study (NCT02378805) assessed 112 patients with Alport syndrome after start of SGLT2i. The study’s primary endpoint was change of albuminuria in albumin/gram creatinine from start of therapy. ResultsCompared to randomized trials investigating the effect of SGLT2i in CKD, the adult patients in this study were younger (38±14 years) and had a better estimated glomerular filtration rate, eGFR, (63±35 ml/min/1.73m2; n=98). Maximum follow up was 32 months. Compared to baseline, at the first three follow-up visits (months 1 to 3, 4 to 8 and 9 to 15) after initiation of SGLT2i-therapy, a significant reduction of albuminuria in milligrams albumin/gram creatinine (>30%) was observed. Mean loss of eGFR was 9±12 ml/min/1.73 m2 almost one year after initiation of SGLT2i-therapy (n=35). At a total of 71 patient-years at risk, 0.24 adverse events per patient year on SGLT2i were reported. ConclusionThis study indicates that, additive to RAS-inhibition, SGLT2i have the potential to reduce the amount of albuminuria in patients with Alport syndrome. Future studies are needed to investigate the long-term effects of SGLT2i on CKD progression in patients with Alport syndrome to assess whether the observed reduction in albuminuria translates to a delay in kidney failure.