Can Ivermectin be used to treat COVID-19 (coronavirus)?
Medically reviewed by Melisa Puckey, BPharm. Last updated on July 12, 2021
Official Answer by Drugs.com
Ivermectin should only be used in patients for COVID-19 in a research setting, as part of a clinical trial.
An in vitro trial has shown ivermectin reduces the number of cell-associated viral RNA by 99.8 % in 24 hours. An in vitro study is when they study cells in a laboratory and not in a living organism.
Clinical trials have been conducted on people to test how well ivermectin works against COVID-19. This is in vivo testing. Currently there is a low level of certainty whether ivermectin helps treat COVID-19 and more studies are needed.
Ivermectin tablets are currently a FDA approved medicine for treatment of intestinal worms, Strongyloides stercoralis and Onchocerca volvulus.
It has been established as safe for human use.
SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) is the virus that causes COVID-19 (coronavirus disease 2019)
What is Ivermectin?
Ivermectin is a medicine currently used to treat parasite infections such as intestinal worms, lice and mites.
Recently ivermectin has also been studied to treat a range of viruses.
How is Ivermectin thought to work on COVID-19?
For the SARS-CoV-2 virus to make you sick, it has to first infect your cells.
Then while inside the cell, the virus makes heaps of copies of itself, so it can spread around your body.
The virus also has ways of reducing the way your body fights the infection.
During the infection of the cell, some viral proteins go into the cell nucleus, and from here they can decrease the body’s ability to fight the virus, which means the infection can get worse.
To get into the nucleus the viral proteins need to bind a cargo transporter which lets them in.
Ivermectin can block the cargo transporter, so the viral proteins can’t get into the nucleus. This is how the scientists believe Ivermectin works against SARS-CoV-2 virus.
By taking Ivermectin, it means the body can fight the infection like normal, because its antiviral response hasn’t been reduced by the viral proteins.
Is Ivermectin an approved medicine by the FDA?
Ivermectin tablets (Stromectol) are an approved by the FDA for use in intestinal worms Strongyloides stercoralis and Onchocerca volvulus.
Ivermectin cream 1% (Soolantra) is FDA approved for rosacea.
Ivermectin is not FDA approved to treat COVID-19.
Ivermectin tablets are also used off-label for a number of other conditions.
Ivermectin intended for animal use should not be taken by humans.
The WHO Therapeutics and COVID-19 living guideline: Ivermectin The WHO Therapeutics and COVID-19 living guideline is the World Health Organization's (WHO) most up-to-date recommendations of treatments of COVID-19. Their recommendation is that ivermectin should not used in patients with COVID-19 unless it is in a research setting, as part of a clinical trial.
This recommendation is the result of a systematic review of randomised clinical trials that used ivermectin for COVID-19. After analysing the information from these studies, they believe that there is a high degree of uncertainty on whether ivermectin is helpful or harmful in treating COVID-19. The uncertainty in some of the ivermectin trials for COVID-19 is due to serious risk of bias
serious risk of imprecision.
There are far fewer randomized controlled trials (RCT) for ivermectin compared to other COVID treatments. The RCT included multiple small trials, that had fewer patients enrolled and had fewer events recorded. More RCT are needed with higher quality of evidence to determine if ivermectin is successful at treating COVID-19.
ICON Clinical Study Results
(Use of Ivermectin Is Associated With Lower Mortality in Hospitalized Patients With Coronavirus Disease 2019: The Ivermectin in COVID Nineteen Study)
The ICON study, which was a multihospital retrospective cohort study, involved 280 patients, 173 patients were treated with at least one oral dose of 200 μg/kg ivermectin and 107 patients had no ivermectin treatment. Patients could also be treated with hydroxychloroquine, azithromycin, or both.
The results from this study showed that:
Overall mortality was significantly lower for the ivermectin group (15%) compared to the usual treatment group (25.2%) using figures from the unmatched cohort.
Mortality for the subgroup of patients who had severe pulmonary involvement was lower in the ivermectin treatment group (38.8%) compared to the usual treatment group (80.7%) from the unmatched cohort.
There was no significant difference between the two treatment groups regarding successful extubation rates of mechanically ventilated patients. Successful extubation is when the patient has had the breathing tube that has been used for mechanical ventilation removed and they can successfully breath on their own.
Length of hospital stay was not significantly different between the ivermectin treatment group and the regular treatment group.
For secondary analysis of the results propensity score matching was performed, which is when the researcher matches a person in the treatment group to a person in the non-treatment group who has similar characteristics. This reduces the effects of confounding and selection bias.
For the propensity matched cohort figures the mortality was significantly lower in the ivermectin treatment group compared to the regular treatment group (13.3% vs 24.5%; odds ratio, 0.47; 95% confidence interval, 0.22-0.99; P < .05).
The study noted that “Interpretation of these findings are tempered by the limitations of the retrospective design and the possibility of confounding” and that “Further studies in appropriately designed randomized trials are recommended before any conclusions can be made.” There has been feedback in regard to this study querying some of the important variables and how they may have affected the study outcome.
Ivermectin to prevent hospitalizations in patients with COVID-19 (IVERCOR-COVID19) a randomized, double-blind, placebo-controlled trial
The IVERCOR-COVID-19 trial was a randomized, double-blind, placebo controlled trial involving 501 patients. The aim of this trial was to determine whether ivermectin treatment could prevent hospitalization of individuals with early COVID-19. One group was treated with ivermectin plus standard treatment and the other group was treated with placebo with standard treatment. Patients were not allowed to take hydroxychloroquine, chloroquine or antiviral drugs.
The results of this trial were published on 2 July 2021 showed that:
The percentage of patients that needed hospitalization was 5.6% in the ivermectin treatment group and 8.4% in the placebo group, but the difference between the two groups was not statistically significantly
There was no statistically significant difference in median time from patient enrollment to hospitalization between the treatment groups. The ivermectin treatment group median time to hospitalization was 3.5 days and placebo group 3 days.
There was no statistically significant difference in mean time from study enrolment until a patient was put on invasive mechanical ventilatory support (MVS). The ivermectin treatment group was 5.25 days compared to the placebo group which was 10 days.
The limitations in this study was noted as a:
low percentage of hospitalized patients
The mean dose of ivermectin was 192.37 μg/kg/day which was below the dose proposed as probably being effective.
Platform Randomised Trial of Treatments in the Community for Epidemic and Pandemic Illnesses (PRINCIPLE)
The PRINCIPLE trial is a current trial investigating treatments for COVID-19 patients in the community who are more at risk of serious illness. The study is investigating a number of different treatments including ivermectin.
Participants in the ivermectin part of the trial will be:
Between the age 18 and 64 years old
With a underlying health condition or shortness of breath due to COVID-19
Must join trial within first 14 days of covid-19 symptoms or a positive test
Will be assigned to receive 3 day course of oral ivermectin treatment
They will be compared to a group of patients receiving standard NHS COVID-19 care.
The ivermectin part of this trial started in June 2021 and results will be published when available.
What happens next?
We will be waiting for the results of more clinical trials in patients to see how well ivermectin works in treating COVID-19.
The randomized clinical trials need to have a high quality of evidence, without the limitations of risk of bias, imprecision, inconsistency between studies, and indirectness of publication bias.
As Ivermectin is already a FDA approved medicine we already know that it has been established as safe for human use when used at the standard dose.
Related Information: COVID-19: Prevention & Investigational Treatments
Bottom line Ivermectin should not be used in patients for COVID-19, unless it is part of a clinical trial.
Currently there is not enough high quality evidence supporting the use of ivermectin for COVID-19 treatment.
More randomized clinical trials with a higher certainty of evidence are needed for ivermectin in the treatment COVID-19.
Ivermectin tablets are FDA approved medicine for some types of intestinal worms and ivermectin cream is FDA approved for rosacea treatment.
Both oral and topical ivermectin have a good safety profile at standard dosing levels.