Researchers have demonstrated that it is possible to use the CRISPR gene-editing tool to stop SARS-CoV-2, the virus responsible for COVID-19, from replicating in infected human cells. The demonstration was done in culture cells in the lab so it is not a forthcoming treatment yet, but this approach could be revolutionary in the medium and long term.

As reported in Nature Communications, the team used the enzyme CRISPR-Cas13b to bind itself to the part of the virus’ genetic code – its RNA – used for replication. The enzyme degrades this bit of information leaving the virus unable to replicate.  

“The flexibility of CRISPR-Cas13 – which only needs the viral sequence – means we can look to rapidly design antivirals for COVID-19 and any new emerging viruses,” senior author Professor Sharon Lewin, from the Peter Doherty Institute for Infection and Immunity in Australia, said in a statement.

CRISPR has been studied as a way to change pieces of DNA so that certain diseases can be treated and even prevented. It is employed in the creation of genetically modified plants and animals, although its use in humans is still limited and, in some cases, controversial. Dr Emmanuelle Charpentier and Dr Jennifer Doudna have been awarded the 2020 Nobel Prize in Chemistry for their development of CRISPR.

Using CRISPR to attack viruses is an interesting approach. The team demonstrated that their approach is capable of dealing with the original version of the virus as well as the alpha variant. It is also effective in inhibiting versions of the virus that have minute mutations that differ from what they have been trained against.

This ability might make it incredibly versatile as a treatment against not just this virus but maybe future versions as well. It could also be applied to other viruses and might be a way to create a treatment for viruses as soon as they begin to spread in humans.

“Unlike conventional anti-viral drugs, the power of this tool lies in its design-flexibility and adaptability, which make it a suitable drug against a multitude of pathogenic viruses including influenza, Ebola, and possibly HIV,” lead author Dr Mohamed Fareh, from the University of Melbourne explained.

While the promise of this approach is exciting, it is important and unfortunate to remember that treatments in humans using CRISPR are likely years away. Given the success of the in-vitro approach, the team is now planning animal studies and then hopefully moving onto clinical trials in humans.