Monoclonal antibodies have a preventive effect against covid, study shows – 11/24/2021

Approved by Anvisa (National Health Surveillance Agency) for initial treatment against covid-19, the drug Regn-Cov2 also acts preventively against the virus, according to a new study.

The drug consists of two monoclonal antibodies casirivimab and imdevimab, which must be administered together. In Brazil, Anvisa approved in an emergency and its use is only in the hospital environment — there will be no sale in pharmacies. The drug was developed by the American society regenerate, associated with the laboratory roche.

In this new study, researchers used 600 mg of casirivimab and 600 mg of imdevimab, the same applied in other research for people with mild and moderate cases of the disease.

People who participated in the research did not have the disease, but were at high risk of being infected, as they lived with someone who had covid-19.

In the study, they found that a single dose of the drug reduced the risk of covid-19 symptomatically by 81.6% over a period of up to 8 months. At this time, none of the participants who received the drug (841) were hospitalized, while six people in the placebo group (842) required medical attention.

What are monoclonal antibodies?

They are laboratory-made versions of the body’s natural defenses to fight infections. Giving people ready-made antibodies can help people who are at high risk of becoming seriously ill because of weak immunity or underlying conditions.

According to Raquel Muarrek*, an infectious disease physician at Rede D’Or, the immune responses are individual, that is, each person will have a type of reaction to the antibodies. “But we have that answer in front of the variations that they are having now. Having soldiers to help, perhaps, the individual will have a better outcome in the end.”

Indications, contraindications and side effects

According to Anvisa, “the indication of drugs is for mild and moderate conditions of the disease, in adults and pediatric patients (12 years or older) with laboratory-confirmed Sars-CoV-2 infection, and who are at high risk of progressing to forms of the disease”.

However, antibodies have not shown benefit in hospitalized patients, and may even be associated with worse clinical outcomes when used. Casirivimab and imdevimab should be given together by intravenous (IV) infusion, and possible side effects include anaphylaxis (acute allergic reaction), fever, chills, hives, itching, and flushing.

According to the scientific works already presented, the cocktail must be administered on the third day after the infection, or until the fifth day. The dose can be varied, this still must be specified by the medical community.

* With information from a report published on 20/04/2021.