As the race for a vaccine against SARS-CoV-2 is on and clinical trials are being sped up, scientists are also spending time to find out if existing medicines could be the next best treatment for Covid-19.
An international team of scientists argues that repurposing an existing medicine is likely to offer a quicker solution than vaccine development. Their research backing their argument was published in the British Journal of Pharmacology, and explained in a press release from Cambridge University.
A team of researchers representing the International Union of Basic and Clinical Pharmacology stated that there will be no magical cure to treat the disease. According to the researchers, a multi-pronged approach is needed to find new, effective medicines, as a vaccine may take over a year to develop.
Better understanding of SARS-CoV-2 = better understanding of what to treat
As scientists unpack the effect of SARS-CoV-2 on the body, we now know that some of the severe symptoms we see in other people are the result of the immune system fighting back, causing damage to tissue and vital organs.
Once the virus enters our bodies, if we have no immunity, it breaks into our cells and replicates throughout the body.
The researchers believe that there are certain areas a successful drug should cover. Professor Anthony Davenport from the University of Cambridge, one of the authors, explains: "Any drug to treat Covid-19 will need to focus on the three key stages of infection: preventing the virus entering our cells in the first place, stopping it replicating if it gets inside the cells, and reducing the damage that occurs to our tissues, in this case, the lungs and heart.”
The research also looks at potential drug targets – a treatment can either target a weak spot in the virus itself, or a weak spot in the body’s defence mechanism.
"We can focus on repurposing drugs that already have regulatory approval or are in the late stages of clinical trials," said Professor Davenport in the statement. "These treatments will have already been shown to be safe and so, if they can now be shown to be effective in Covid-19, they could be brought to clinical use relatively quickly."
Are there any promising existing drugs?
While the efficacy of drugs such as chloroquine, hydroxychloroquine and lopinavir/ritonavir have been discredited in previous studies, scientists are now looking at their next best candidate, remdesivir.
This drug was originally developed to treat Ebola, but clinical trials found it to be effective against the coronavirus. The FDA has therefore given emergency approval for it to be used in patients with severe Covid-19.
There is also the option of treatments developed from monoclonal antibodies, but they are expensive to produce.
Why not vaccines?
As reported by Health24, the development of a vaccine is a lengthy process, as it involves pre-clinical tests before it can move on to clinical testing (where it’s tested on humans). Then, there are at least four further phases of clinical testing before a vaccine can be regarded as safe and effective.
Right now, several companies are racing to be first to produce the ultimate vaccine, but Dr Alexander warns that we should be patient.
"Some of the vaccines may not work, so the more drugs that can be tested and the more we know about the targets, the more likely we are to get something which is effective. The very specificity of vaccines means they are limited in which viruses they can neutralise. The lessons we learn and the drugs we generate will hopefully provide a greater degree of protection, not just against the Covid-19 virus, but also against the next viral threat."
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