A post-marketing surveillance study of agalsidase alfa-treated patients with Fabry disease in Japan (Sasa et al., 2019 [6]) reported rates of eGFR decline of −0.95 to −0.98 mL/min/1.73 m2 in 238 male patients with baseline proteinuria of <0.3 g/24 h, and −3.24 to −4.52 mL/min/1.73 m2 in 56 male patients with baseline proteinuria of >0.3 g/ 24 h. The gene discussed is GLA; the disease is Fabry disease.