COVID-19: After Lilly, Regeneron Bags EUA for its Antibody Therapy

On November 21st, the F.D.A issued an emergency use authorization (EUA) for Regeneron Pharmaceuticals Inc.’s COVID-19 antibody cocktail therapy and became the first in the United States or Europe to do so. The experimental treatment was given to US President Donald Trump that he said helped cure him of the disease and had trials showing it to be 95% effective. The President received it through the FDA’s ‘compassionate use’ provision, where unapproved drugs are administered to seriously ill patients who have no other treatment options.

Regeneron’s Technology

The treatment works by combining two drugs, casirivimab (REGN10933) and imdevimab (REGN10987), and administering them both in an IV. These drugs are monoclonal antibodies raised against the spike protein of the SARS-CoV-2 virus. The two antibodies create an “antibody cocktail” to seek out and bind to the coronavirus’ spike protein and prevent its entry into healthy human cells. The cocktail is a mix of an antibody made by the company and another isolated from humans who recovered from COVID-19 infection. The rationale behind having two antibodies that act on the same epitope is to prevent drug resistance caused by the virus’s mutation.

Monoclonal antibodies are derived from a unique white blood cell that has the desired reaction against a particular antigen. This unique cell is then cultured and exposed to the antigen as a means of encouraging antibody production. These antibodies are then harvested and used to boost the patient’s immune system.

Regeneron announced that the clinical evidence from outpatient trials suggests that monoclonal antibodies such as REGEN-COV2 have the greatest benefit when given early after diagnosis and in patients who have not yet mounted their own immune response or who have a high viral load.

According to the FDA, the monoclonal antibodies should be administered together for the treatment of mild to moderate COVID-19. Despite their use for treating COVID-19, these antibodies are not authorized for hospitalized patients due to COVID-19 or require oxygen therapy for the disease. This includes those who are 65 years of age or older or who have certain chronic medical conditions.

Regeneron said it expects to have REGEN-COV2 treatment ready for ~80,000 patients by the end of this month and 200,000 patients by the first week of January 2021, and 300,000 patients in total by the end of the month. The White House celebrated the “promising results” and noted that the administration had spent close to half a billion dollars to support large-scale manufacturing of Regeneron’s antibody treatment for delivery to US hospitals.

Competition

Eli Lilly recently announced the results from its randomized, placebo-controlled Phase 2 study of bamlanivimab (LY-CoV555), showing that the antibody therapy could reduce a patient’s viral load with a mid-level dose. An emergency use authorization soon followed, and Eli Lilly has estimated that it can produce 1 million doses by the end of 2020. The company additionally made a deal with the US government to produce 300,000 doses in exchange for $375 million. While there is certainly no shortage of US-based cases at the moment (~12 million), Eli Lilly’s current deal and being first to market could compete with Regeneron’s candidate.

Not only are there treatments like the monoclonal antibodies, but progress has been made on vaccines as well. Hot on the heels of these companies are vaccines developed by Pfizer and BioNTech, and Moderna, who claim that their vaccine candidates are 95% and 94.5% effective, respectively. Pfizer has already submitted a EUA application to the FDA, while Moderna will seek approval as part of “operation warp speed” by the end of the month.

The amount of Emergency Use Authorizations being given to well-funded and thoroughly researched technologies is heartening in the midst of this pandemic. It will be interesting to keep track of all of the innovations that we will see before this virus is under control.

By Eduardo Longoria

Editor: Rajaneesh K. Gopinath, Ph.D.

Related Article: Cheaper and Fridge-Stable AstraZeneca Vaccine is 90% Effective in Preventing COVID-19

References

1. https://investor.regeneron.com/news-releases/news-release-details/regenerons-regen-cov2-first-antibody-cocktail-covid-19-receive

Author

Eduardo Longoria