7 May 2020
US expert on feline coronavirus says research “is far more advanced in veterinary than human medicine, but they do not recognise any animal coronavirus diseases of veterinary importance as models”.
James Westgate
Job Title
One of the world’s leading experts on feline coronavirus (FCoV) has accused the human health sector of ignoring veterinary science in the fight against COVID-19.
The virus has killed more than 30,000 people in the UK and the global death toll is approaching 300,000 as the pandemic pushes health systems around the world to the very brink.
Governments everywhere have been scrambling to develop a vaccine for the novel virus, as well as find drugs and treatment protocols to increase survival rates in those already suffering acute effects of infection.
The US government has given emergency approval to the use of Ebola drug remdesivir and the UK is trialling the treatment, too, along with other potential candidates.
As a newly emergent disease in humans, these trials can be unpredictable and difficult to interpret. But similar drugs have been used for some years in trials against the disease caused by FCoV in cats – FIP.
FIP has low incidence, but the disease has an extremely high fatality rate in cats, vaccination is unreliable, and disease transmission and development follows an unpredictable course.
One man who knows this better than most is Niels Pedersen at the University of California, Davis, who published a paper last year showing how a very similar drug to remdesivir was used to successfully treat FIP.
His work with the nucleoside analogue “GS-441524” could have big implications for the current crisis, but Dr Pedersen believes his and similar studies are simply being ignored.
He said: “Veterinary medicine, with all of its experience with animal coronavirus diseases, is being ignored at this time. However, this is par for the course.
“It seems that we, as veterinarians, fully believe in the concept of one medicine. This is given only lip service by the human researchers.
“The FIP virus and SARS-CoV-2 are closely related to each other, and both FIP and feline enteric coronavirus would be models for both treatment and vaccination.
“Research into coronavirus diseases is far more advanced in veterinary than human medicine, but they do not recognise any animal coronavirus diseases of veterinary importance as models.”
Speaking about the work done with remdesivir, Dr Pedersen – an emeritus professor in medicine and epidemiology – explained how similar the drugs he used against FIP in cats are to those being used in humans to fight COVID-19.
He added: “Gilead [the US manufacturer of remdesivir] increased the potency of GS-441524 by adding one phosphate group, and then protecting that phosphate group to allow absorption into cells by surrounding it by some alkyl and aryl groups. This protected monophosphate of GS-441524 is remdesivir.
“Once into cells, cellular esterases cleave off all of the alkyl and aryl groups to yield GS-441524 monophosphate. This is then triphosphorylated to the active adenosine nucleotide analogue, which is what blocks viral RNA synthesis.”
Both remdesivir and GS-441524 inhibit the virus’ ability to replicate in the body of a host, and Dr Pedersen believes both should be being used in human trials.
He said: “We found that GS-441524 is equally virus inhibitory than remdesivir – and because it was directly absorbed, there was no advantage to using remdesivir.
“Moreover, there was the chance that remdesivir might be more toxic, but the big thing was that it was much more expensive to make over GS-441524.
“If it were me, I would be using GS-441524 in human trials in parallel with remdesivir. My prediction is that GS-441524 would be more effective, less toxic, and much cheaper.”
