Abstract - 600984 Disclosed are crystalline polymorphs of sodium 2-(5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-triazol-3-ylthio)acetate including those characterised by peaks at 4.90, 9.83, 25.29, 6.86, 8.41, 10.13, 17.92, and 23.10 °2?±0.1°2?, characterised by an endothermic point onset at about 62°C as determined by differential scanning calorimetry with a heating rate of about 10°C/min. Other crystalline forms are also disclosed such as those characterised by peaks at 4.22, 8.51, 12.80 and 16.95 °2?±0.1°2?, and characterised by an endothermic point onset at about 173°C as determined by differential scanning calorimetry with a heating rate of about 10°C/min； characterized by peaks at 6.9, 10.1, 22.6, 23.3, 23.9, 25.2, 28.3 and 29.0 °2?±0.1°2?； characterized by peaks at 10.3, 17.8 and 25.2 °2?±0.1°2?； and also a form which is characterised by peaks at 10.5, 22.9, 23.2 and 24.6 °2?±0.1°2?. Further disclosed is a method for preparing a crystalline polymorph of sodium 2-(5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-trizaol-3-ylthio)acetate comprising: a) contacting amorphous sodium 2-(5-bromo-4-(4-cyclopropylnaphthalen-1-yl)-4H-1,2,4-trizaol-3-ylthio)acetate with water and ethyl acetate； and b) isolating the solids from the mixture prepared in step a). Crystalline forms as disclosed above are useful for treating or preventing hyperuricemia, or a disease caused by elevated uric acid levels, and / or for treating or preventing gout.
