Paris (AFP)

The research institute of Professor Didier Raoult in Marseille has put online the summary of a new study extolling the merits of hydroxychloroquine against the coronavirus, the methodology of which immediately aroused new criticism from the medical world.

"Hydroxychloroquine (derived from chloroquine, a drug against malaria, NDLR) combined with azithromycin (an antibiotic, NDLR), administered immediately after diagnosis, is a safe and effective treatment against Covid-19", affirms the conclusion of this brief pre-publication, presented Thursday to Emmanuel Macron during his surprise visit to the Hospital-University Institute (IHU) Méditerranée Infection.

1,061 patients tested positive for the new coronavirus received for "at least three days" this treatment promoted by the specialist in infectious diseases.

This percentage is "significantly lower" than in "patients treated under other regimes both at the IHU and in all public hospitals in Marseille", says this summary, which also specifies that "no cardiac toxicity has been observed ".

The full study has not yet been made public.

Many scientists welcome the large number of patients included (compared to a few dozen for the previous ones) but argue that because of the way the study is designed, there is nothing to conclude that the treatment "avoids the worsening of symptoms and prevents persistence of the virus and contagiousness in most cases ", as the conclusions state.

"Unfortunately in the absence of a comparative arm (control group receiving a placebo, Editor's note), it is extremely difficult to know whether the treatment is effective or not," said Friday Arnaud Fontanet, epidemiologist at the Pasteur Institute and member of the board. scientist Covid-19, on RMC / BFM TV.

"These results are just null and void, it does not tell us anything about the effectiveness of the treatment," prevails epidemiologist Catherine Hill. She also mentioned the absence of a control group and the fact that according to available public data, at least 85% of people heal spontaneously, without any treatment.

The epidemiologist, now retired, points to AFP a likely bias in the selection of participants, with patients tested positive who probably would never have developed symptoms, or very mild.

The IHU indeed proposes to carry out tests in a broad way to the patients who present themselves within its walls (the published text evokes 38,617 patients tested between March 3 and April 9), whereas, in the rest of the country these tests are still reserved in priority for hospitalized cases and nursing staff.

In fact, the study participants have less severe forms than the average of the confirmed cases of Covid-19: the trial of Pr Raoult includes 95% of patients whose degree of severity is "low", 2.4% "medium" cases and 2.6% of cases whose severity is considered "high".

- "Great legitimation" -

However, according to the analysis of more than 70,000 Chinese patients published on February 24 in the American medical journal Jama, 81% of the cases had moderate clinical forms, 14% severe and 5% "critical".

On April 3, the International Society of Antimicrobial Chemiotherapy, which had published Professor Raoult's first study, had already expressed its concerns, explaining that the article did not meet the "expected quality standards".

The French infectious disease specialist is at the center of a global debate on the use of chloroquine and hydroxychloroquine to fight the coronavirus.

Some doctors, some countries and elected officials are calling for widespread administration of this drug, but a large part of the scientific community and health organizations are calling for a rigorous scientific validation, warning of the possible risks for patients, especially those with heart disease.

A European trial called "Discovery" has been launched in several countries to test four treatments, including hydroxycholoroquine, and other studies specifically studying its effectiveness have started, notably at the Angers University Hospital.

Pending the results, France has adopted a cautious position: hydroxychloroquine is authorized in hospitals only, and only for severe cases.

The Minister of Health, Olivier Véran, had called last weekend not to skip the stages, believing that we would soon know the first intermediate results of the studies launched.

If the Elysée assures that "we must not see any political dimension" to the displacement of Emmanuel Macron, many see on the contrary "a formidable legitimization of this researcher" however controversial.

In an editorial, the famous journal Science is worried that the French president "feeds the craze around a treatment whose effectiveness is not proven".

© 2020 AFP