Hydroxychloroquine could not prevent the development of coronavirus infection

The drug, which was previously considered a promising drug against the development of Covid-19, has again shown its ineffectiveness in real patients.

When the SARS-CoV-2 virus was just beginning its march across the planet, hydroxychloroquine was considered one of the promising agents against the pathogen. This drug exhibits a certain antiviral activity in vitro: scientists suggest that this happens due to the disruption of the processes of interaction of viral proteins with ACE2 molecules, which serve as a kind of “gateway” for penetration into the cell.

However, many studies have shown that hydroxychloroquine does not have a significant effect in the treatment of coronavirus infection. The new study, the results of which are published in The New England Journal of Medicine, can be said to finally put an end to this drug. This work shows that hydroxychloroquine is unable to prevent the development of Covid-19 within four days of potential exposure.

A team of researchers led by David Bulwair of the University of Minnesota studied 821 people without symptoms of Covid-19 and without confirmed infection with SARS-CoV-2 who in any way had close contact with people who had the coronavirus. Close contact meant being less than 1.8 meters from the infected for at least 10 minutes.

The subjects were divided into two groups, the first of which (414 people) took hydroxychloroquine, and the second (407 people) took placebo. The regimen for taking the drug was as follows: 800 milligrams once, then 600 milligrams for six to eight hours, and then 600 milligrams daily for four days. The drugs were delivered to the subjects at home, and the scientists tracked their condition according to the reports sent.

During the study, Covid-19, confirmed by laboratory or by symptoms, developed in 107 subjects: 49 from the first group and 58 from the second (11.8 and 14.3 percent of the total number of groups, respectively). Such an absolute difference in incidence is not statistically significant, therefore, hydroxychloroquine did not have a noticeable effect on the risk of developing coronavirus pneumonia.

The authors of the work note that due to the lack of diagnostic testing practice in the United States, the majority of the subjects were diagnosed by a combination of characteristic symptoms (loss of smell, cough, fever, shortness of breath, sore throat and muscles). This was a definite limitation of the study but did not question the results in general.