What the research says about using ivermectin to treat Covid-19

This is a summary of a presentation done by Dr Andrew Hill from the University of Liverpool to the American National Institutes of Health. He has been researching ivermectin for the global health agency Unitaid and the World Health Organisation. He was joined in his presentation by the doctors from the Front Line Covid-19 Critical Care Alliance.

Research in favour of ivermectin

There have been 18 small trials that involved a collective 2,100 patients. They were fairly small and fairly short.

These trials have separately shown a decrease in viral load and an improvement in markers doctors use to measure inflammation, faster times to hospital discharge and faster clinical recovery, as well as a 75% reduction in mortality rates.

This outcome was improved by higher doses over longer periods (five days) and not through a once-off dose – the normal dose for ivermectin when used to treat parasites.

Concern remains over higher doses having side effects.

Similar early successes were noted for drugs like chloroquine and lopinavir.

Studies in animals have shown that ivermectin can cause birth defects, so it is contra-indicated for pregnant women or women of child-bearing age.

In 2021 the National Institutes of Health changed its advice on ivermectin to reflect that it is neither for nor against the use of ivermectin to treat Covid-19.

Research against ivermectin

Dr Halima Dawood explained the current available information that South African doctors have on the use of ivermectin for the treatment of Covid-19.

In the most recent review conducted by the National Essential Medicines List Therapeutic Guidelines Sub-Committee on Covid-19 (“the committee”), only two randomised control trials out of 171 publications could provide any analysable information on the use of ivermectin for prevention of Covid-19.

The vast majority of studies that were included in the committee’s final analysis had not undergone peer review and contained very small numbers of participants. The studies were very difficult to judge together or compare, as the dosing strategies and primary outcomes were different.

Many of the trials did not investigate ivermectin alone against a placebo, but rather tested a combination of ivermectin and another medicine, either of which could have had an effect on the virus. This makes it almost impossible to tell whether any effect that is seen is due to ivermectin, the companion medicine or a combination of the two.

There is also no consensus regarding certain factors in the use of ivermectin for preventing and treating Covid-19, such as what dose of ivermectin to use, whether it should be intravenous, in pill form or via a nasal spray, how long it should be used for, and which patients should receive it.

On 4 March 2021, an article was published in the Journal of the American Medical Association detailing the latest clinical trial to test whether ivermectin worked as a treatment for mild Covid-19.

The study’s results were that by day 21, 82% in the ivermectin group and 79% in the placebo group had resolved symptoms. The conclusion that was reached by the authors was summarised as follows:

“Among adults with mild Covid-19, a fiveday course of ivermectin, compared with placebo, did not significantly improve the time to resolution of symptoms. The findings do not support the use of ivermectin for treatment of mild Covid-19, although larger trials may be needed to understand the effects of ivermectin on other clinically relevant outcomes.”

“While the evidence on the efficacy of ivermectin is shifting all the time, the current and emerging evidence does not support the use of ivermectin for the prevention or treatment of Covid-19,” said Dawood.