• Direct: latest news of the coronavirus
  • Health: WHO resumes studies with hydroxychloroquine
  • Studies: Chloroquine, a key drug against the virus

The hydroxychloroquine is no preventive treatment after effective exposure , high - risk or moderate risk to Covid-19 when used prophylactically within four days of exposure, the data of a study published in The New England Journal of Medicine , coordinated by teams from the universities of Minnesota, United States, and Montreal, in Canada.

The results constitute a new 'twist' around the scientific discussions on the usefulness, efficacy and safety of this molecule in patients affected by Covid-19, mainly in hospitalized patients who have been the bulk of most of the studies. clinical studies with chloroquine or hydroxychloroquine for Covid-19 conducted to date.

The new, first randomized study that has tested this antimalarial and antirheumatic drug as preventive therapy on 821 participants (414 received hydroxychloroquine and 407 placebo) has not shown that hydroxychloroquine is effective in preventing viral contagion after exposure.

66% of those who participated in the study are health professionals who have had close contacts with Covid patients. The rest were people aged between 33 and 50, half male and the other female.

Regime and inclusion

The dosage regimen for hydroxychloroquine was 800 mg once, followed by 600 mg every 6 to 8 hours thereafter, and subsequently 600 mg daily for an additional 4 days for a total 5-day cycle (19 tablets total). If the participants had gastrointestinal complaints, they were advised to divide the daily dose into two or three doses.

The "contacts" were defined as being less than two meters away from a person sick for more than 10 minutes , without the patient or the person carrying out the contact will use facial mask or screen protector. However, the absence of symptoms was one of the requirements to be included in the study.

"This trial has not demonstrated a significant benefit of high-dose hydroxychloroquine as post- exposure prophylaxis for Covid-19. Whether pre-exposure prophylaxis would be effective in high-risk populations is a separate issue, with ongoing trials for To end the pandemic, a reduction in community transmission is needed, "says David R. Boulware of the University of Minnesota, and one of the study's directors, whose data was obtained electronically.

Other studies are underway to assess whether pre-exposure prophylaxis could be effective in high-risk populations , but it is still unknown.

To date, no medication has been shown to prevent transmission of SARS-CoV-2 . Both chloroquine and the hydroxychloroquine-derived molecule have in vitro activity against SARS-CoV and SARS-CoV-2, so since the beginning of the pandemic these molecules have been included in international trials, such as Solidarity, sponsored by the World Health Organization (WHO) .

According to the latest study in The New England , 107 of the participants developed the disease, 49 of them in the group that received hydroxychloroquine and 58 in the group that received a placebo. This represents a 2.4% reduction in the risk of developing COVID-19, which " is neither statistically nor clinically significant, " says Boulware.

Disparate data coming and going

The publication of these data coincided with the announcement yesterday by the WHO to resume the trials that had been temporarily suspended as a precautionary measure after the results published last May 22 by The Lancet and which indicated that not only had they not been evidenced benefits, but the administration of hydroxychloroquine was related to an increase in mortality in Covid-19 patients, associated or not with other drugs, mainly antibiotics.

However today, The Lancet has released a correction to the investigation that sparked controversy over its effectiveness. Three of the article's authors, "Hydroxychloroquine or chloroquine with or without macrolide for the treatment of COVID-19: a multinational registry analysis," have retracted their study. The reason: they were unable to complete an independent audit of the data supporting their analysis.

As a result, they have concluded that "they can no longer answer for the veracity of the data sources . " The Lancet takes scientific integrity issues very seriously, and there are many outstanding questions about Surgisphere and the data that were supposedly included in this study. Following the guidelines of the Publications Ethics Committee (COPE) and the International Committee of Medical Journal Editors (ICMJE), institutional reviews of research collaborations on the company are urgently needed.

While WHO Director-General Tedros Adhanom Ghebreyesus said yesterday that the Data Safety and Surveillance Committee of the international Solidarity trial "had seen no justification for varying research security protocols after reviewing all the data," The Lancet also recalled the results obtained in May that analyzed more than 96,000 patients hospitalized by Covid-19 from centers around the world. The French health authorities have also advised against its use as a treatment for patients with Covid-19 confirmed by PCR or by symptoms.

Numerous clinical research groups, including several Spaniards, continue to study the potential benefit of this molecule as preventive or therapeutic therapy, although in light of the disparate conclusions, the scientific controversy is well served and makes it clear that more research is necessary.

In accordance with the criteria of The Trust Project

Know more

  • Science and health
  • Covid 19
  • Coronavirus
  • Pharmacology

Hallucinations and heart rhythm disturbance, the effects of the drug that Trump takes and supports Bolsonaro

Antiviral remdesivir, also useful in not so severe patients with Covid

HealthA 'bullet' with triple antiviral ammunition against Covid-19

Close links of interest

  • News
  • Translator
  • Programming
  • Calendar
  • Horoscope
  • Classification
  • League calendar
  • Films
  • Schools
  • Masters
  • Cut notes
  • Rich
  • Universities
  • Themes
  • FC Famalicão - FC Porto
  • Maritime - Vitória Setúbal
  • Benfica - Tondela
  • Vitória Guimarães - Sporting CP