Disclosed are polymer sFlt-1 conjugates, variants of sFlt-1, compositions comprising such conjugates and variants, including cysteine variants of sFlt-1. Also disclosed is the use of such conjugates, variants and compositions in methods to inhibit the activity of VEGF, to inhibit angiogenesis, and to treat or reduce at least one symptom of diseases and conditions in which it is desirable to inhibit VEGF activity and/or angiogenesis.