Are antimalarials effective against coronavirus? While Donald Trump and his entourage continue to sponsor its use to mark a decisive point in the battle against Sars-Cov-2 and order millions of doses to India, the scientific community is unable to give a clear signal.

If on the one hand the world’s leading experts urge caution by emphasising the current inconsistency of experimental evidence, on the other, doctors across the world have begun prescribing chloroquine and hydroxychloroquine to patients with Covid-19. If we add the suspected economic interests , then, understanding who to put trust in becomes a big problem.

Here’s what we know.

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Antimalarials, antirheumatic

Chloroquine and hydroxychloroquine are drugs that for over 70 years have been used in the prophylaxis of malaria , to prevent the parasite that causes it from nesting in our body following the sting of mosquito vectors. The mechanism of action is still not very clear, but the drugs work and the fact that they are also cheap does not hurt. However, attention must be paid to the doses and the patient ‘s medical history must be assessed in order not to incur the most serious adverse effects, including cardiovascular collapse.

Over time, chloroquine and hydroxychloroquine have also found a further application and today they are successfully used in the treatment of some rheumatic diseases, such as systemic lupus erythematosus and rheumatoid arthritis. Rheumatologists routinely prescribe them, knowing the pros and cons.

Also antiviral?

In the scientific world the idea that these drugs have an antiviral action has been proposed for some time now, but studies have not always given unequivocal results. Much depends on the virus being studied. However, one of the strong motivations that led to starting to administer chloroquine and hydroxychloroquine to those who contract Covid-19 is the fact that these drugs had already given some evidence of efficacy against another coronavirus, that of Sars in 2002-03. The hypothesis was and remains that by acting on the pH of the cells, these molecules prevent the virus from infecting and / or successfully completing the replication cycle.

Based on some in vitro experimentscarried out in February, Wuhan’s doctors were the first to administer old antimalarials to patients, reporting apparent success . But, due to the chaos of the context and the haste, the scientific community believes that the conclusions presented were not reliable . Same thing for the now famous French trial , which would have treated patients without absolving all the trappings that an experiment of this type should have (primarily randomisation) – which in the opinion of world experts makes the data inconclusive , at the equal to anecdotal reports that have since accumulated.

To get to grips with it – also claim by the WHO, also the advocate of the mega trial Solidarity – the only way is to start serious, reasoned clinical trials, with criteria that allow us to understand whether the administration of the drug (whatever it is) produces a actual benefit for treated patients compared to a control group.

The preventive way

Yet in the last few days the scientific front appears to be more frayed than ever. A letter published in the Annals of the Rheumatic Diseases journal  signed by some rheumatologists of Sapienza, then also supported by the European League against Rheumatism , seems to be a demonstration. In the document, the experts evaluate the pros and cons of the preventive use of chloroquine and hydroxychloroquine, an experiment that could be started on the basis of in vitro experiments that have shown (they are preliminary data ) how to administer the drugs to the cells in culture already before their coronavirus exposurelimit the pathogen’s ability to replicate . If the prophylactic path were to be tried – rheumatologists say – you can rely on the knowledge on the safety profile of drugs accumulated over years and years of use and vigilance on rheumatic patients.

A warning, however: drugs should not be missing (which is happening, especially in the United States) for those patients who today are suffering from diseases that benefit from certified treatment with antimalarials.

Clash in the White House

A glimpse of this complex panorama can be had by peering at what is happening in the United States. President Trump has long been a strong supporter of the use of antimalarials, so much so that he promised a substantial supply (29 million doses ordered from India), ignoring and clashing with the experts of his task force, first of all Anthony Fauci, World-renowned immunologist and head of the National Institute of Allergy and Infectious Diseases which supports the most rigorous – and undoubtedly slowest scientific line . The risk is to use huge resources without obtaining any objective benefit.

In this regard, there are also those who put forward the hypothesis that behind the position taken by the White House there are economic interests, linked to the participation of President Trump himself, but also to a part of his entourage and other people close to him, in the business of the pharmaceutical companies that would have the most to gain.

The FDA, meanwhile, has authorized the use of hydroxychloroquine as rescue medication to treat patients Covid-positive and requests in the US are skyrocketing, among the most diverse testimonies of doctors, divided between enthusiasm and blatant scepticism.