In a preliminary study, American researchers found an “increased risk of mortality” in patients with coronavirus who had been treated with hydroxychloroquine.
- A new study on the effects of chloroquine has been carried out on American Covid-19 patients
- These patients were of an age and health condition that put them at higher risk than average
- In this population, the antimalarial was not very effective
The controversy around hydroxychloroquine continues. According to a large-scale preliminary study, this antimalarial administered to Covid-19 patients around the world would not be very effective. The results of this work were published on April 16 in the journal MedRxiv. However, they have not yet been peer-reviewed by a medical journal.
To reach these conclusions, the researchers studied 368 patients with the coronavirus from the network of public hospitals for American veterans. The latter, mostly black men with a median age of over 65, either died or were discharged from hospital before April 11. The scientists divided the subjects into three groups: those treated with hydroxychloroquine (HC) alone; those to whom the hydroxychloroquine-azithromycin cocktail (an antibiotic) was administered, promoted in France by Professor Didier Raoult, director of the IHU Méditerranée in Marseille, and those who have never received hydroxychloroquine. Result: they observed that more people died in the hydroxychloroquine alone group (28%), compared to the cocktail group (22%) and the group without HC (11%).
Given that at the start the patients who received hydroxychloroquine were sicker and more at risk than the others (smokers, people with diabetes or with a cardiovascular and pulmonary history), the researchers corrected this initial imbalance statistically this imbalance . Nevertheless, “the increased risk of mortality in the hydroxychloroquine-only group persisted”they note, recalling however that the specificity of the patients studied prevents this finding from being generalized to an entire population.
What about the controversy around hydroxychloroquine?
Hydroxychloroquine, a drug used for many years against malaria and against lupus, is administered in many countries in emergency to severe cases of Covid-19, but its consequences are very controversial.
In France, this treatment is especially praised by Professor Didier Raoult who associates it with a pulmonary antibiotic called azithromycin. “After six days of treatment, 75% of patients are cured of the virus”, he says in a first study published on March 20, carried out on 26 patients (six of whom abandoned the current experiment). “The majority of patients (81.3%) had favorable results (…). Only 15% required oxygen therapy”, then wrote his team in conclusion of a second study involving 80 people. In his final research, carried out on 1,061 people who tested positive for Covid-19, a “good clinical result” as well as a “virological cure” were obtained in ten days in 91.7% of the patients tested. On the other hand, 47 patients (4.4%) were still infected with the virus at the end of treatment. One “poor clinical outcome” was also observed in 46 patients (4.3%), of whom five died (0.47%).“The combination of hydroxychloroquine and azithromycin, when started immediately after diagnosis, is a safe and effective treatment for Covid-19, with a mortality rate of 0.5%”concludes Raoult, assuring that this treatment “avoids complications and eliminates virus persistence and contagiousness in most cases.”
However, these studies have come under much criticism. The latest was only published in summary form, making it difficult to assess, experts say. What’s more, many scientists wonder about the patients studied. Of 38,617 patients tested by the IHU Méditerranée between March 3 and April 9, 1,061 patients were selected for the study because they met the “inclusion criteria”. Some therefore wonder if the patients most affected or at risk would not have been excluded from the experiment. Finally, the absence of a control group, without treatment, makes it impossible to compare the treated sample.
Several large-scale trials underway to compare potential treatments
This is why several large-scale trials comparing groups of Covid-19 patients following different treatments, or not, are currently underway. Among them, the European trial Discovery, led by Professor Florence Aderinfectious disease specialist at the Croix-Rousse hospital in Lyon, who will test four potential remedies for the coronavirus.
“A number of works have been carried out in vitrothat is to say in a laboratory, and we retained a certain number of molecules which were molecules that we used in HIV or another molecule that has already been tested in Ebola (…) We tests for other drugs that are not necessarily drugs and medications used for viral infections, including chloroquine and hydroxychloroquineexplains Florence Ader to the press. The idea is that when you progress and you understand much better the way the virus is structured, the way it works and the way it interacts with the body, it allows you at that time to have completely virus-specific strategies. This leads to two innovations, which are on the one hand to find targets which allow us to develop new drugs but which are completely specific to this virus — these are so-called ‘second generation’ drugs — and we are already in that dynamic. Of course, the Holy Grail is to find a vaccine or vaccines that are specific enough to generate an immune response that is completely targeted to this virus..”
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