Paris | Effectiveness of corticosteroids, but only in severe cases, uselessness of hydroxychloroquine or antivirals used against the AIDS virus … We can now see more clearly on the treatments against COVID-19, even if their range remains limited.
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THOSE WHO WALK
Dexamethasone (and corticosteroids)
This is the only treatment that has reduced mortality from COVID-19, although this is only true for one category of patients (severe cases that require administration of oxygen).
For these patients, the World Health Organization (WHO) and the European Medicines Agency (EMA) have recommended dexamethasone since September. They are based on the findings of a large UK study, Recovery.
On the other hand, dexamethasone should not be given at the onset of the disease, as it lowers the immune system. This is why it is effective in severely affected patients: it reduces the runaway immune system responsible for the inflammation characteristic of severe forms.
Beyond dexamethasone alone, work published on September 2 in the American medical journal Jama showed that other drugs in the same family, corticosteroids, reduced mortality by 21% after 28 days in severely affected patients.
This has led WHO to recommend “the systematic use of corticosteroids in patients with severe or critical disease.”
According to a study published at the end of May in the American journal New England Journal of Medicine, this antiviral initially developed against Ebola hemorrhagic fever slightly reduces the recovery time of hospitalized COVID-19 patients (from 15 to 11 days on average).
• Read also: Remdesivir has “little or no effect” on mortality
But remdesivir has not shown any benefit in terms of reducing mortality, as another study released Thursday, conducted in more than 30 countries with support from WHO, reaffirmed.
The drug “seems to have little or no effect on patients hospitalized for COVID-19, if we are to believe the mortality rates, the onset of ventilation or the length of hospitalization”, says this study.
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Sold by the Gilead laboratory under the trade name Veklury, on July 3 it became the first drug against COVID to receive conditional European marketing authorization.
However, it arouses more enthusiasm in North America than on the Old Continent.
In France, the Haute Autorité de Santé (HAS) judged that its interest (or “actual benefit”) was “low”.
Separately, the EMA said on October 2 that it would investigate reports that “acute kidney problems” may be linked to taking remdesivir.
Like corticosteroids, they are used in the most severely ill patients. The goal is to prevent blood clots, one of the serious complications of COVID-19.
THOSE WHO DO NOT WALK
It is the drug that has generated the most attention since the start of the pandemic, as it has become the subject of political debate. One of its main supporters has indeed been US President Donald Trump.
Among scientists, it is the controversial French professor Didier Raoult who defends tooth and nail this drug, used depending on the country as a treatment for malaria or autoimmune diseases.
But studies have ruled: Hydroxychloroquine is not effective against COVID-19.
This observation was especially fueled by the Recovery study, which showed in early June that this molecule did not reduce mortality (detailed results were published on October 8 in the New England Journal of Medicine).
Hydroxychloroquine was not part of the treatments given to Donald Trump when he contracted COVID-19.
This saga was however marked by an academic scandal: at the beginning of June, the prestigious journal The Lancet had to withdraw a critical study on hydroxychloroquine due to strong suspicions of fraud. This scandal has bolstered the opinion of staunch supporters of the drug despite the mounting evidence.
Used against the AIDS virus, the combination of these two drugs is not effective in patients hospitalized with COVID-19.
Again, it was the Recovery trial that led to this conclusion as early as June 29 (before the publication of the results detailed in The Lancet October 6).
Marketed under the name Kaletra, the combination of lopinavir and ritonavir does not reduce mortality or the risk of being placed on mechanical ventilation, according to the results of Recovery. This treatment also does not shorten the length of hospital stay.
THOSE WE TEST
These so-called “monoclonal” antibodies are manufactured in the laboratory. When injected intravenously, they are supposed to support the immune system to neutralize the coronavirus.
Donald Trump himself received an experimental treatment of this type, manufactured by the American biotechnology company Regeneron. After encouraging preliminary results, this treatment will now be tested on a large scale as part of the Recovery trial.
Another American pharmaceutical group, Eli Lilly, is developing a similar treatment. On Tuesday, he announced the suspension of the trial, for unspecified safety reasons.
These new treatments “are promising (…) but overall, their effectiveness or safety has not yet been proven,” said Anthony Fauci, one of the leading experts on the US government, recently.
This involves transfusing patients with plasma (the liquid part of the blood) taken from people previously infected but now recovered, so that they benefit from their antibodies.
According to some studies, this treatment has been shown to be effective in treating the Ebola virus or SARS, which is related to the new coronavirus.
But all experts agree that more clinical trials are needed to compare plasma to standard care. This comparison is ongoing as part of the Recovery trial.
Among other treatments being tested, Recovery is evaluating the effectiveness of tocilizumab, which is hoped to fight the inflammatory phenomenon responsible for the most severe cases.
Finally, other avenues are being explored through “repositioning” programs: this involves reviewing already existing molecules to see if they could be effective against COVID-19.
In France, the Institut Pasteur de Lille received a donation of five million euros from luxury giant LVMH to test a molecule whose name it has not disclosed. She was spotted as part of a repositioning program.