New stability indicating reverse phase-high performance liquid chromatographic (RP-HPLC) method was developed and validated for the estimation of atazanavirsulphate(ATV) in bulk and dosages forms by using C18column Phenomenix (250 mm x4.6 mm,5μm), with a mobile phase consisting of a acetonitrile and water (80:20 v/v) at a flow rate of 0.5 mL/min.The detection was carried out at 248 nm and retention time(Rt) of atazanavir sulphate was found to be 3.989 min. The response of detector was linear in the concentration range of 10-50μg/mL (n=5),with the regression coefficient of determination r2 was found to be 0.999. Atazanavir sulphate was subjected to different stress conditions as per ICH guidelines like acidic alkaline,oxidative,thermaland the results showed that it was more sensitive towardsbasic degradation.
