CONCURRENT ESTIMATION OF SOFOSBUVIR AND VELPATASVIR IN RAW AND TABLETS USING STABILITY INDICATING RP-HPLC METHOD

A stability indicating RP-HPLC method is developed and evaluated to quantify sofosbuvir and velpatasvir in raw and tablets forms. The method involves separation and analysis of sofosbuvir, velpatasvir and their stress degradants using Spursil C18 (250 × 4.5 mm and i.d., 5 μm particle size) analytical column with a mixture of potassium dihydrogen phosphate (0.1 M) and methanol (pH 4.5, 60:40 v/v) as the mobile phase. The analysis was done using a photodiode array detector at 240 nm. Calibration curves showed linearity in concentration range 10–30 (velpatasvir) and 40–120 μg/mL (sofosbuvir). Good linearity (R ≥ 0.9998), good precision (RSD ≤ 0.138%, n = 5) and good accuracy (% recovery ̴100%) for velpatasvir and sofosbuvir were achieved. Stress degradation studies were performed on powdered tablet sample in athe cidic, basic, oxidative, thermal and photolytic atmosphere. The method showed no interference from the degradation products formed by applied stress conditions. Application of the proposed method to the commercially available tablets was carried out successfully. The performance of the proposed method was compared with those from previously published HPLC methods and they were satisfactory.