FDA plays a critical role in protecting the United States from threats such as emerging infectious diseases, including the Coronavirus Disease 2019 (COVID-19) pandemic. FDA is committed to providing timely guidance to support response efforts to this pandemic.

Due to the current public health emergency, FDA is issuing this guidance to assist sponsors in the development of monoclonal antibodies (mAbs) and other therapeutic proteins for use as COVID-19 therapeutics. A critical quality control measure for these products is the development and implementation of a potency assay(s) adequate to ensure that each lot is consistently produced with the potency necessary to achieve clinical efficacy and that such potency is maintained over the shelf life of the product.