The present invention relates to
in vitro sialylated human
factor H protein or biologically active sialylated fragments or biologically active sialylated variants thereof, wherein the
protein does not comprise trisia lylated N-glycans of the structure A3G3S3 (NaNaNa), for use in a method of treatment, wherein the method of treatment involves administering subcutaneously said
in vitro sialylated human
factor H protein or biologically active sialylated fragments or biologically active sialylated variants thereof subcutaneously. The methods of treatment comprise treating complement-mediated diseases such as C3 glomerulopathy (C3G), atypical hemolytic uremic syndrome (aHUS), age-related
macular degeneration (AMD) or paroxysmal nocturnal hemoglobinuria.