Estimation of protein aggregates in Darbepoetin alfa formulations by developing a single validated analytical method

Darbepoetin alfa is a new generation recombinant human erythropoiesis stimulating agent having extended half-life as compared to recombinant human erythropoietin. It is given as a life-saving drug for anemic disorders caused by chronic kidney diseases, cancer, etc. With the presence of commercial formulations of darbepoetin biosimilars in the market and non-availability of any established method in literature or testing guidelines in any compendia for their purity and quality, this research aims to develop a sensitive and robust method to determine the aggregate impurities by using size exclusion chromatographic technique. The method was optimized for sharp and high-resolution monomer peak of darbepoetin and other interferences which was further validated according to ICH Q2(R2) guidelines. The developed method was further tested on the commercial samples to verify the same. Additionally, stress testing of samples was done to simulate the after-production exposure and stability assessment. The results demonstrated that the method for analysing aggregates in darbepoetin is complying the criteria of being sensitive, specific, accurate, robust and reliable.