The specious arguments of Didier Raoult to defend his study on hydroxychloroquine

This was to be the flagship article that would prove the effectiveness of hydroxychloroquine against Covid-19: in early April, Didier Raoult and his teams posted an ambitious study online involving more than 30,000 patients, conducted by the University Hospital Institute (IHU) of Marseille

The specious arguments of Didier Raoult to defend his study on hydroxychloroquine

This was to be the flagship article that would prove the effectiveness of hydroxychloroquine against Covid-19: in early April, Didier Raoult and his teams posted an ambitious study online involving more than 30,000 patients, conducted by the University Hospital Institute (IHU) of Marseille. On June 2, the professor, now retired, ended up announcing his withdrawal on Twitter, "in solidarity with Professor Lagier, threatened by management".

The National Agency for the Safety of Medicines and Health Products (ANSM) has announced its intention to take legal action regarding this study, which has been strongly criticized since May 28. Several medical companies published a column in Le Monde accusing Didier Raoult of having conducted the "largest known wild therapeutic trial". They accuse him of having continued to administer hydroxychloroquine as part of a scientific experiment without any authorization.

A "stand of fools", swept the interested party, interviewed on BFM-TV. In recent days, Didier Raoult has long defended his method, his style and his results in a media tour which led him to express himself on the continuous news channel BFM-TV but also on media which have supported, like Sud Radio, the covidosceptic site France-Soir, the program "Touche pas à mon poste" ("TPMP", on CNews), or the WebTV of the Republican People's Union (UPR), the sovereignist party of François Asselineau. He presented the facts to his advantage, even if it meant coming to terms with reality.

The Forgotten Blame of December 2021

Faced with those who accuse him of having conducted an unauthorized trial by continuing to prescribe hydroxychloroquine despite these numerous disavowals, the researcher opposes that he has "perfectly the right to prescribe off-label", the marketing authorization the market which also gives the framework in which a drug is supposed to be prescribed, in accordance with the available scientific data.

Freedom of prescription is indeed defended by the public health code, and many drugs are prescribed off-label, particularly in paediatrics. On France-Soir, Mr. Raoult even explains that the Council of the Order of Physicians, before which he appeared in December 2021, confirmed that he was entitled to prescribe hydroxychloroquine. He had however been sanctioned with a reprimand, for having precisely promoted the drug without sufficient scientific proof, causing his patients to take reckless risks. The Council of the Order then appealed, not to cancel the sanction, but to increase it.

A biased method

Another ambiguity is the methodology of its latest study involving 30,423 patients treated at the Marseille IHU. "To be able to see the differences, you need sufficient numbers", boasts Didier Raoult on Sud Radio. Contradictory remarks with those he made in June 2020: as a "very good methodologist", he declared that "any trial that includes more than 1,000 people is a trial that seeks to demonstrate something that does not exist".

Didier Raoult's detractors, who criticized him for studies on too small numbers, must recognize him this time with a more satisfactory statistical power. This study nevertheless suffers from the same selection bias: patients with a contraindication, in particular cardiac, to hydroxychloroquine, were placed in the control group (those who do not receive the treatment), whereas they are by definition more at risk of serious forms of Covid-19, distorting the comparison.

Many other biases make his self-congratulations fragile. “Do you know what the mortality rate is for patients with Covid at the IHU? It's 10%. All the studies that have been published elsewhere have mortality rates of 20%, "he boasted on the set of" TPMP ". But, as epidemiologist Mahmoud Zureik points out on Twitter, the comparison does not hold, because the IHU does not have an intensive care unit: the most serious cases have therefore been transferred to other Marseille hospitals, which reduces the mortality rate.

Dubious sources or read backwards

In his media interventions, Mr. Raoult also cited questionable sources, such as the aggregator C19Early.org, explaining that of the "2,600 studies analyzed", concerning "500,000 patients", including 393 studies centered on hydroxychloroquine , "they find an efficiency that is the same as ours".

Except that C19Early is not a scientific journal. This anonymous website automatically references all the studies published on the subject, such as C19HCQ and HCQTrial before it, or its cousins ​​C19Zinc and C19VitaminD. This opaque and unscrupulous network puts studies of very disparate quality on the same footing, and regularly twists their conclusions in favor of hydroxychloroquine. Network classified as unreliable by the American disinformation observatory, NewsGuard.

The microbiologist also cites more serious sources, such as an observational study by the AP-HP published in May 2020 in the British Medical Journal. “If you look at this study by [French immunologist Matthieu] Mahévas, he explains on BFM-TV, there are a few people he treated with hydroxychloroquine and azithromycin, for whom there is a significant difference for prevention of resuscitation and prevention of death. But the study doubly says the opposite, protests its author. On the one hand, the association between hydroxychloroquine and azithromycin is not evaluated there, in particular because of too marginal numbers - an interpretation that Didier Raoult has always disputed; on the other hand, at the global level, it proves the infectiologist wrong. “The conclusion is that hydroxychloroquine, at the dose recommended by Didier Raoult, did not modify the number of intensive care visits or survival. So there is no effect, ”sums up Mr. Mahévas with Le Monde.

Conspiratorial exaggerations

To explain the lawsuit against his treatment, the professor emeritus repeatedly denounces a pharmaceutical industry that has become too powerful, with too high financial stakes. “Of course there are considerable risks of corruption,” he explains on the UPR website, citing the very real, heavy fines paid by Pfizer for fraud, or the manipulation of data for the drug. Vioxx, in the early 2000s.

But the conspiratorial fantasy is never far away, as when he declares, in explanation of the critical articles of which he is the subject, that "subsidies of the French press by the pharmaceutical industry are considerable" - he seems to confuse at best with state subsidies to the press, at worst invent completely.

Likewise, he repeatedly reiterates that the World Health Organization's (WHO) decision to halt trials of hydroxychloroquine was made after the publication of a fraudulent study, "a gross fake", in The Lancet, in May 2020. This study has indeed been retracted, but Didier Raoult forgets to specify that many publications had already highlighted, in previous weeks, the potential toxicity of chloroquine and hydroxychloroquine, in the United States. United as in France, and that their ineffectiveness had already been noted, including by researchers attached to the IHU.