INTRODUCTION

This chapter provides guidance about the use of bioassays to measure the biological activity of erythropoietin (EPO). Based on a relative potency approach described in general chapter Design and Development of Biological Assays 〈1032〉, the biological activity of an unknown EPO preparation typically is determined by comparison to the biological activity of a Reference Standard (RS). For this purpose, a USP Erythropoietin for Bioassays RS has been developed. The assays described in the chapter are not applicable to forms of EPO that have been engineered to prolong their half-life.