Treatments for COVID-19: some progress, no panacea

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)

It 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 the 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 British 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 also 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 the other drugs in the same family, corticosteroids, reduced mortality by 21% after 28 days in severely affected patients.

This led the WHO to recommend “the systematic use of corticosteroids in patients with severe or critical form”.

Remdesivir

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 proven benefits in terms of reducing mortality, as confirmed by another study released Thursday and conducted in more than thirty countries with the support of the WHO.

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 COVID drug 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 Oct. 2 that it would investigate reports that “acute kidney problems” could be linked to taking remdesivir.

Anti coagulants

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

Hydroxychloroquine

It is the drug that has caused the most ink to flow since the start of the pandemic, because it has become the subject of a 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 (the detailed results were published on October 8 in the New England Journal of Medicine).

Hydroxychloroquine was not part of the treatments administered 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 confirmed the opinion of fierce supporters of this drug despite the evidence that accumulates.

Lopinavir-ritonavir

Used against the AIDS virus, the combination of these two drugs is not effective in patients hospitalized for COVID-19.

Here again, it was the Recovery trial that led to this conclusion as of June 29 (before the publication of the detailed results in The Lancet October 6).

Marketed under the name Kaletra, the lopinavir-ritonavir combination does not reduce mortality or the risk of being placed on artificial ventilation, according to the results of Recovery. This treatment does not shorten the duration of hospitalization either.

THOSE WE TEST

Synthetic antibodies

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 test, for security reasons not detailed.

These new treatments “are promising (…) but overall, their effectiveness or their safety have not yet been proven”, recently underlined Anthony Fauci, one of the principal experts of the American government.

Plasma

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 in the same family as the new coronavirus.

But all experts agree that more clinical trials are needed to compare plasma to standard care. This comparison is underway as part of the Recovery trial.

Other tracks

Among the other treatments tested, Recovery is currently 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 via “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 the luxury giant LVMH to test a molecule whose name it has not disclosed. She was spotted as part of a repositioning program.