Aims/IntroductionThe slope of estimated glomerular filtration rate (eGFR) decline (eGFR slope) in early‐stage type 2 diabetes patients might predict the future risk of end‐stage renal disease. Type 2 diabetes patients who show rapid progressive eGFR decline are termed rapid decliners. Several studies of rapid decliners have investigated the efficacy of sodium–glucose cotransporter 2 inhibitors (SGLT2i) in patients with advanced renal dysfunction; however, no studies, to our knowledge, have focused on patients with preserved renal function. Therefore, we investigated the efficacy of SGLT2i in rapid decliners with preserved renal function.Materials and MethodsThis study enrolled type 2 diabetes patients with baseline eGFR ≥60 mL/min/1.73 m2 who had been treated with SGLT2i for ≥3 years. Among these individuals, we defined those with annual eGFR declines ≥5 mL/min/1.73 m2 per year before SGLT2i administration as rapid decliners. The primary end‐point was the change in eGFR slope after SGLT2i administration.ResultsAmong 165 patients treated with SGLT2i for ≥3 years, 21 patients were rapid decliners with preserved renal function. The mean age and eGFR at SGLT2i administration were 58.6 years and 87.1 mL/min/1.73 m2, respectively. The mean annual eGFR slope improved significantly in those administered SGLT2i compared with the control group (−1.00 and −4.36 mL/min/1.73 m2 per year, respectively; P < 0.001). Notably, the steeper the eGFR slope before starting SGLT2i administration, the larger the improvement of eGFR slope, which was independent of the reduction of albuminuria.ConclusionsEarly intervention with SGLT2i may have renoprotective effects in type 2 diabetes patients with rapid decline and preserved renal function.