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A doctor or pharmacist might mix the powder with sugar and water to produce a nasal spray.
A nasal spray that blocks the absorption of the SARS-CoV-2 virus completely protected the ferrets it was tested on, according to a small study released Thursday by an international team of scientists. The study, which was limited to animals and has not yet been peer-reviewed, was evaluated by several health experts at the request of The New York Times.
If the spray, which scientists have described as non-toxic and stable, were to work in humans, it could provide a new way to fight the pandemic. A daily spray on the nose would behave like a vaccine.
“Having something new that works against coronavirus
it’s exciting, “said Dr. Arturo Casadevall, president of immunology at the Johns Hopkins Bloomberg School of Public Health, who was not involved in the study.” I could imagine this is part of the arsenal. “
Work has been ongoing for months by scientists from Columbia University Medical Center in New York, Erasmus Medical Center in the Netherlands, and Cornell University in Ithaca, New York. The study was funded by the National Institutes of Health and Columbia University Medical Center.
The team would request additional funding to pursue clinical trials in humans. Dr. Anne Moscona, a Columbia pediatrician and microbiologist and co-author of the study, said she filed for a patent for the product and hoped Columbia University would get closer to the federal government’s Warp Speed operation or large pharmaceutical companies that they are looking for new ways to fight the coronavirus .
The spray directly attacks the virus. It contains a lipopeptide, a cholesterol particle linked to a chain of amino acids, the building blocks of proteins. This particular lipopeptide corresponds exactly to an amino acid tract in the virus spike protein, which the pathogen uses to attach to a human lung or airway cell.
Before a virus can inject its RNA into a cell, the peak must actually be decompressed, exposing two chains of amino acids, to fuse with the cell wall. When the tip lifts to complete the process, the lipopeptide in the spray inserts itself, attaching itself to one of the tip’s amino acid chains and preventing the virus from attaching itself.
“It’s like I’m closing a zipper but putting another inside, so the two sides can’t meet,” said Matteo Porotto, a Columbia University microbiologist and one of the paper’s authors.
The job was described in a document sent to the prepress server bioRxiv Thursday morning and was presented to the magazine Science for peer review.
Dr Peter J. Hotez, dean of Baylor College of Medicine’s National School of Tropical Medicine, said the therapy looked “very promising.”
“What I would like to know now is how easy it is to scale production,” he said.
In the study, the spray was given to six ferrets, who were then split into pairs and placed in three cages. Two ferrets who had been given a placebo spray and one ferret who had been deliberately infected with SARS-CoV-2 a day or two earlier also entered each cage.
Ferrets are used by scientists who study influenza, severe acute respiratory syndrome, and other respiratory diseases because they can catch viruses through their noses just like humans do, although they also infect each other through contact with feces or by scratching each other. and biting.
After 24 hours together, none of the sprayed ferrets caught the disease; all ferrets in the placebo group did.
“Virus replication has been completely blocked,” the authors wrote.
The protective spray sticks to cells in the nose and lungs and lasts about 24 hours, Moscona said. “If it works that well in humans, you could sleep in a bed with someone infected or be with your infected children and still be safe,” he said.
The amino acids come from a stretch of the spike in protein coronavirus es that rarely changes. Scientists tested it against four different variants of the virus, including the well-known “Wuhan” and “Italian” strains, and also against the coronavirus es which cause SARS and Middle East respiratory syndrome.
In cell cultures, it protected completely against all strains of the pandemic virus, well enough against SARS and partially against MERS.
Lipoprotein can be made inexpensively as a freeze-dried white powder that doesn’t need refrigeration, Moscona said. A doctor or pharmacist might mix the powder with sugar and water to produce a nasal spray.
Other laboratories have designed antibodies and “mini-proteins” that also block the SARS-CoV-2 virus from entering cells, but these are chemically more complex and may need to be stored at low temperatures.
Moscona and Porotto have been collaborating for 15 years on similar “fusion inhibiting” peptides, they said in a conference call. They have developed some against measles, Nipah, parainfluenza and other viruses.
But those products have attracted little commercial interest, Porotto said, because an effective measles vaccine already exists and because the deadly Nipah virus appears only occasionally in places as far away as Bangladesh and Malaysia.
New monoclonal antibodies coronavirus have been shown to prevent and cure infection, but are expensive to manufacture, require refrigeration, and must be injected. Australian scientists tested a nasal spray against COVID-19 in ferrets, but it works by improving the immune system, not directly targeting the virus.
Because lipopeptides can be shipped as a dry powder, they could also be used in rural areas of poor countries that lack refrigeration, Moscona said.
Moscona, a pediatrician who usually works on parainfluenza and other viruses that infect children, said she was more interested in bringing the product to poor countries that may never have access to the monoclonal antibodies and mRNA vaccines Americans may soon. to have. But he has little experience in that arena, he said.
“I’ve always been a basic scientist,” she said. “I’ve never developed drugs or brought anything to the FDA or anything like that.”
Donald G. McNeil Jr. c. 2020 The New York Times Company
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