The fight against Covid-19, for more than a year, has been based on the screening strategy, barrier gestures and of course vaccination. Support has also progressed well. Lthe care provided at the hospital has improvedin particular thanks to corticosteroids (dexamethasone), effective in severe patients.
On the other hand, antiviral treatments, to prevent the disease or treat infected people, before the inflammatory phase when the patient’s condition deteriorates, have so far not really proven themselves.
A hopeful strategy, that monoclonal antibodies, could however improve patient care. Indeed, this treatment, administered sufficiently early in the development of the disease, is effective in preventing the worsening of symptoms.
Since March 15, a temporary authorization for use had been validated by the Medicines Agency (ANSM), for these antibodies to be administered in 80 hospitals, on certain patients (over the age of 80, over 70 years with comorbidities, affected by immune disorders). From September 3, the ANSM that it extends access to monoclonal antibodies :
Treatment of COVID-19 :
The casirivimab and imdevimab combination is indicated for the treatment of COVID-19 confirmed by a positive PCR test, in patients aged 12 years and over and at high risk of progression to a severe form of the disease (immunocompromised patients, at risk of complications or aged over 80):
- not requiring oxygen therapy due to COVID-19, and within a maximum period of 5 days after the onset of symptoms;
- hospitalized due to COVID-19, having a negative serological test and requiring non-invasive oxygen therapy (not intubated).
Prevention of COVID-19:
The casirivimab and imdevimab combination is indicated for prophylaxis for certain patients aged 12 years and over who are at risk of progressing to a severe form of the disease:
- for pre-exposure prophylaxis of SARS-CoV-2 infection in patients who have not responded to vaccination (who have not developed antibodies) or who are not eligible for vaccination;
- for post-exposure prophylaxis (contact case) of SARS-CoV-2 infection in patients who are non-responders or weak responders to vaccination, or who are not eligible for vaccination.
Remember that when he had contracted Covid-19, Donald Trump was treated with a drug based on synthetic antibodies. From November 2020, bamlanivimab was authorized on an emergency basis by the United States Medicines Agency for people who have developed mild or moderate symptoms of Covid-19 and who are at high risk of developing a severe form of the disease. These antibodies have also been available in university hospitals in Germany since the beginning of January, under certain conditions.
The principle: monoclonal antibodies boost the immune system
It is a product synthesized in the laboratory, which is injected intravenously in one go. It results from the cloning of antibodies from patients convalescing from Covid-19, with the aim of strengthen the immune system.
It is not intended to reduce symptoms, but prevents the virus from continuing to replicate in the body. Concretely, in the event of infection, the immune response induces the production of several thousand antibodies. “The idea of this treatment is to seek out the most effective neutralizing antibodies, to produce them in the laboratory – they are therefore indeed artificial antibodies – and to stimulate, by injection, a so-called passive immunity”, explained to BFMTV Yves Coppieters, epidemiologist and professor of public health.
How: by binding to the “S” protein
How it works ? By attaching to the Spike protein present on the surface of the coronavirus to attach and penetrate cells, the antibody cocktail limits the infection of new cells.
“The administration of monoclonal antibodies, by preventing the penetration of the virus into the cells and thus by fighting against its replication could neutralize the virus in the early phase of the infection”,says the Ministry of Health.
To whom will they be administered?
“This treatment will complement the therapeutic measures already in place to treat patients at risk of developing severe forms of Covid-19″, indicates the ministry.
This treatment could be very effective if administered early enough in the development of the disease, in preventing the worsening of symptoms. If the disease has already progressed and the patient has a severe form, scientists have found that it is not effective. It will therefore be administered to patients at risk of developing a more serious form and being hospitalized.
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