On 21st November the US Food and Drug Administration (US FDA) issued an emergency use authorization (EUA) for Casirivimab and Imdevimab for treatment of mild to moderate COVID-19.
These two agents are authorized as a combination therapy for use in adults and pediatric population. This combination can be used in COVID-19 patients above 12 years of age and weighing at least 40 kgs (about 88 pounds). This also includes patients who are 65 yrs of age or older or who have certain underlying chronic medical conditions.
During the clinical trials, it was observed that COVID-19 patients who received Casirivimab and Imdevimab together possessed a lesser risk for hospitalization or reduced number of emergency hospital visits. The safety and efficacy of this combination in COVID-19 patients is still being evaluated.
Casirivimab and Imdevimab must be administered together via an intravenous infusion.
Casirivimab and Imdevimab are monoclonal antibodies. Monoclonal antibodies are laboratory made proteins that imitate the immune system's functions. It helps the body in fighting against pathogens (a biologic agent that is infectious and can cause disease or illness). These antibodies act against the spike proteins of the coronavirus. Due to inhibition of these proteins, the attachment and entry of the virus into the human cells is prevented.
FDA Commissioner Stephen M. Hahn, M.D said, "The FDA remains committed to advancing the nation's public health during this unprecedented pandemic. Authorizing these monoclonal antibody therapies may help outpatients avoid hospitalization and alleviate the burden on our health care system. As part of our Coronavirus Treatment Acceleration Program, the FDA uses every possible pathway to make new treatments available to patients as quickly as possible while continuing to study the safety and effectiveness of these treatments."
The issuance of EUA is different from an FDA approval. The FDA evaluates the available scientific information and assesses the potential risks and benefits of the drug during an emergency. The data supporting this EUA is based on a randomized double blind trial with 799 non-hospitalized adult with mild to moderate COVID-19.
Out of 799 patients 266 received a single intravenous infusion of 2,400 milligrams Casirivimab and Imdevimab (1,200 mg each), 267 received 8,000 mg Casirivimab and Imdevimab (4000 mg each) and 266 received a placebo (no active drug), within three days of testing positive for SARS-COV- 2.
EUA fact sheets include dosing, instructions, potential side effects and drug interactions. Possible side effects of Casirivimab and Imdevimab are acute allergic reaction (anaphylaxis), fever, chills, hives, itching & infusion related reaction like rashes, tachycardia, hypotension (low BP) , headache.