A Quality by Design Approach for Development and Validation of Simple and Robust Reversed Phase (RP) Stability Indicating LC Method for Estimation of Baricitinib and its Impurities

To develop a stability-indicating and quality by design-based RP HPLC method to determine baricitinib and its process and degradation impurities. The separation was achieved using a Unison UK C18 column (Make:Imtakt) with dimensions of 150mm x 4.6mm and a particle size of 3μm.The mobile phase consisted of mobile phase A (10mM Ammonium acetate buffer, pH 5.20 with dilute Glacial Acetic acid solution) and mobile phase B as acetonitrile in gradient mode with an initial ratio of 85:15v/v. The flow rate was set at 1ml/minute and the column temperature was maintained at 35°C. Buffer and acetonitrile in the ratio of 50:50(%,v/v) was used as a diluent. The detection was performed at 220 nm using a photodiode array (PDA) detector with an injection volume of 10 μL and ambient sample temperature. The resolution for baricitinib and ten impurities was found to be greater than 2.0 for any pair of impurities.The method was evaluated according to ICH standards for various validation parameters. Method robustness was assessed using QbD principles through the design of experiments. Forced degradation studies were conducted under stress conditions such as acidic, basic, oxidation, thermal, humidity, photolytic, and hydrolysis. The proposed method is valuable for determining all process and degradation impurities to establish a stability-indicating method.