Researchers have found that an anti-parasitic drug already available around the world can kill the novel coronavirus grown in cell cultures within 48 hours, an advance that may lead to the development and trial of a new clinical therapy for COVID-19.
According to the study, published in the Journal Antiviral Research, the drug, Ivermectin, stopped the virus, SARS-CoV-2, from growing in cell culture within 48 hours.
"We found that even a single dose could essentially remove all viral RNA by 48 hours and that even at 24 hours there was a really significant reduction in it," said study co-author Kylie Wagstaff from Monash University in Australia.
The scientists said Ivermectin is an approved anti-parasitic drug that has also been shown to be effective in vitro against a broad range of viruses including HIV, Dengue, Influenza and Zika virus.
However, Wagstaff cautioned that the tests conducted in the study were in vitro and that trials needed to be carried out in people.
Frequently Asked Questions
A vaccine works by mimicking a natural infection. A vaccine not only induces immune response to protect people from any future COVID-19 infection, but also helps quickly build herd immunity to put an end to the pandemic. Herd immunity occurs when a sufficient percentage of a population becomes immune to a disease, making the spread of disease from person to person unlikely. The good news is that SARS-CoV-2 virus has been fairly stable, which increases the viability of a vaccine.
There are broadly four types of vaccine — one, a vaccine based on the whole virus (this could be either inactivated, or an attenuated [weakened] virus vaccine); two, a non-replicating viral vector vaccine that uses a benign virus as vector that carries the antigen of SARS-CoV; three, nucleic-acid vaccines that have genetic material like DNA and RNA of antigens like spike protein given to a person, helping human cells decode genetic material and produce the vaccine; and four, protein subunit vaccine wherein the recombinant proteins of SARS-COV-2 along with an adjuvant (booster) is given as a vaccine.
Vaccine development is a long, complex process. Unlike drugs that are given to people with a diseased, vaccines are given to healthy people and also vulnerable sections such as children, pregnant women and the elderly. So rigorous tests are compulsory. History says that the fastest time it took to develop a vaccine is five years, but it usually takes double or sometimes triple that time.
"Ivermectin is very widely used and seen as a safe drug. We need to figure out now whether the dosage you can use it at in humans will be effective - that's the next step," Wagstaff said.
"In times when we're having a global pandemic and there isn't an approved treatment, if we had a compound that was already available around the world then that might help people sooner," she said.
Although the mechanism by which Ivermectin works on the virus is not known, the scientists said it is likely, based on its action in other viruses, that it works to stop the virus 'dampening down' the host cells' ability to clear it.
"As the virologist who was part of the team who were first to isolate and share SARS-COV2 outside of China in January 2020, I am excited about the prospect of Ivermectin being used as a potential drug against COVID-19," said Leon Caly, study co-author from the Royal Melbourne Hospital in Australia.
The scientists further cautioned that the use of Ivermectin to combat COVID-19 would depend on the results of future pre-clinical testing and ultimately clinical trials.