The ancient anti-malarial drug hydroxychloroquine (HCQ) may well have a beneficial effect on corona patients if they receive it from the first day of their hospitalization. A study in fourteen Dutch hospitals shows that patients who received the drug had a lower risk of ending up in ICU by more than half. Use of HCQ did not reduce covid-19 mortality.
The study was led by internist-infectiologists Jolanda Lammers and Paul Groeneveld of Isala in Zwolle. Lammers and Groeneveld are convinced that the beneficial effect is a result of the early administration of HCQ. In patients receiving the related chloroquine, there was no significant effect on the number of ICU admissions compared to standard care.
Both infectiologists emphasize that their research results must be confirmed in one randomized controlled trial, a study in which comparable patients are blindly divided between a treatment group and one or more control groups. The article by the Zwolle researchers has already been published peer reviewed, assessed on value by colleagues.
The Dutch study is a so-called retrospective, observational study. The researchers looked back at the fare of patients who were admitted to hospital with covid-19 in March of this year. During that period, the treatment guideline For Covid-19 patients, doctors have the choice between prescribing hydroxychloroquine, closely related chloroquine or standard care.
“That’s what makes our retrospective study special, in a way it is also somewhat prospective”, says Groeneveld. Prospective research looks ahead. For example, people with covid-19 receive different treatments and then the effect is determined.
Because hospitals could choose how they treated patients during the first corona wave, a kind of control groups were created spontaneously. One hospital gave its patients HCQ, the other chloroquine and the third standard care. HCQ is now mainly given to rheumatism patients and also to people with Q fever.
Difference from other studies
In the meantime, many studies have been published that show that HCQ would have no or even a negative effect on covid-19 patients. The most extensive is the UK Recovery trial, with thousands of patients participating. That study looked at the effect of HCQ on mortality 28 days after the onset of covid-19. That effect was not there. The UK study led to the discontinuation of many other studies.
“The Recovery trial often involved critically ill patients. Moreover, in many cases they only received hydroxychloroquine and a relatively high dose after many days,” says Lammers. “We looked at nearly 1,100 patients treated from day 1. And we looked at their discharge from the hospital, admission to the ICU or death.” The patients received the dose of 2,400 milligrams of HCQ prescribed in the Netherlands at the time in five days.
So it only concerned people in the covid wards. “Not too sick patients. In that early stage of the infection we see a positive effect of the treatment with HCQ.”
Her colleague Groeneveld adds: “It’s actually just like pneumonia. Then you give antibiotics to prevent it from getting worse and people have to go to IC.”
Professor Andy Hoepelman, head of the infectious diseases department at UMC Utrecht, calls the study by his Isala colleagues “very valuable”. “The researchers have neatly arranged their data,” says Hoepelman. “Statistically it also looks good and they adjusted well for factors influencing the outcomes.”
Still, the Utrecht professor thinks that the days of HCQ are over. “Most experts say it doesn’t work. In the United States it has disappeared from the guidelines. A recent one Amsterdam study shows that it has toxic side effects and no effect on mortality. “
The latter study compares outcomes in hospitals that provided standard care to covid-19 patients with hospitals where chloroquine or hydroxychloroquine was prescribed. No distinction is made between the latter two means, which makes comparison with the Isala study difficult.
HCQ does not appear to have a preventive protective effect against the corona virus. Care workers who received preventive HCQ for eight weeks contracted covid-19 no less often than colleagues who were not treated. However, it is about a study with only 125 participants.