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# Pandemic Monoclonal Antibody Potency Assay Guidance
- URL: https://www.fdaweb.com/pandemic-monoclonal-antibody-potency-assay-guidance/
- Published: 2021-01-14T12:00:00.000Z
- Updated: 2026-09-14T16:42:44.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5148447

FDA has issued an immediately-in-effect guidance, *Covid-19: Potency Assay Considerations for Monoclonal Antibodies and Other Therapeutic Proteins Targeting SARS-CoV-2 Infectivity*, to assist sponsors in developing monoclonal antibodies and other therapeutic proteins for use as Covid-19 therapeutics. The [document](https://www.fda.gov/regulatory-information/search-fda-guidance-documents/covid-19-potency-assay-considerations-monoclonal-antibodies-and-other-therapeutic-proteins-targeting?utm%5Fmedium=email&utm%5Fsource=govdelivery) says that a critical quality control measure for such products is the development and implementation of a potency assay 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 product’s shelf life.

Typically, according to the guidance, FDA engages with sponsors on their development of appropriate potency assays throughout drug development, often over years.

“Given the compressed development timelines associated with therapeutics intended to treat Covid-19, FDA is issuing this guidance to provide more detailed recommendations to drug developers with the goal of facilitating more complete submissions,” the agency says.

The guidance applies only to monoclonal antibodies and other therapeutic proteins designed to bind to viral receptors on host cells, inhibit viral entry, and/or elicit Fc-mediated effector function. Vaccines, hyperimmune globulins, gene therapies, cell therapies, and convalescent plasma are not within the guidance’s scope.