Coronavirus infections may soon be marked with a puff of exhaled breath after the Food and Drug Administration approved the first respiratory-based Covid-19 test in the United States on Thursday.
The emergency approval of the InspectIR Covid-19 Breathalyzer is a meaningful milestone in the years-long quest to develop more breath-based diagnostics as well as innovative new tests for Covid, experts said. And it will likely be the first of many similar respiratory-based Covid tests, experts said.
“I think this is a really exciting development for the whole field of respiratory analysis,” said Cristina Davis, associate vice chancellor for interdisciplinary research and strategic initiatives at the University of California, Davis, who has developed her own coronavirus test. “This is a big step forward.”
But breath tests still pose challenges in the real world, and this particular device has several practical limitations, scientists said. The machine required to perform the tests is large – about the size of a carry-on suitcase – and can only be used by trained operators supervised by healthcare professionals.
And many devices would be needed for comprehensive screening, as each machine can only process about 20 samples per hour, according to InspectIR Systems, a small five-man company based in Frisco, Texas.
The company cited high accuracy rates for its tests, but some experts said they wanted to examine the data underlying its application to the FDA before approving this test method.
In addition, many healthcare institutions and mobile test sites where the devices can be used have already adopted other forms of rapid testing, which are now widely available. InspectIR officials said the final pricing plans had not yet been determined.
It may take 10 to 12 weeks for the first devices to hit the market, said John Redmond, a co-founder of InspectIR Systems, on Friday. The company said it planned to produce about 100 units a week, according to the FDA, but it was not immediately clear when production would reach that level.
“We have been thinking about these types of tests for the whole pandemic, and we waited a bit for the first one” to be approved, “said Dr. Wilbur Lam, a pediatric hematologist and bioengineer at Emory University and the Georgia Institute of Technology and an expert in Covid testing.
“The devil is in the details to really determine how useful this thing will be,” he said.
Many diseases cause physiological changes that change the compounds we exhale, and there has long been interest in developing respiratory tests for a wide range of diseases, from lung cancer to liver disease.
When the pandemic began, several research teams began trying to identify unique chemical patterns in the respiration of Covid patients, and many researchers and companies have developed respiratory-based coronavirus tests that could be used to quickly and non-invasively screen large groups of people for the virus. .
Some Covid breath tests have already been tested in pilot programs or approved for use in other countries, but the InspectIR Breathalyzer would be the first to hit the US market.
To use the device, patients blow into a vacuum cleaner tube attached to a chemical analyzer. “It’s a chemistry lab in a box,” said Mr. Redmond. The machine then analyzes the levels of five volatile organic compounds, or VOCs, that together make up a “spirit imprint” of Covid, said Mr. Redmond. (InspectIR said it could not reveal what the five connections are.) The results are delivered within three minutes, the company said.
“It’s really fast and pretty impressive,” said Nathaniel Hafer, a molecular biologist and test expert at UMass Chan Medical School.
Expanding the types of samples that can be used to detect the virus is “really valuable,” he added. “Not everyone can give a nose sample very easily.”
In a company-sponsored study of 2,409 asymptomatic individuals, the breathalyzer had a 91 percent sensitivity, meaning that of those who tested positive for the virus in a PCR test, the device marked 91 percent of those who suspected positive, according to documents. published by the FDA It had a specificity of 99 percent, which means that it did not detect any signs of the virus in 99 percent of those who received a negative result from a PCR test.
Susan Butler-Wu, a clinical microbiologist at the Keck School of Medicine at the University of Southern California, said she wanted to see more independent data on the device’s performance and more details on exactly what compounds it detected.
“The use of VOCs is not well developed for diagnosing infection,” she said. “I would not feel comfortable using it to diagnose patients without getting some more real data.”
Certain foods and substances can interrupt breathing tests, scientists noted. And the instructions for the InspectIR Breathalyzer specify that people should not eat, drink or use tobacco products for the 15 minutes before taking the test. Those who test positive should also have the result confirmed with a PCR or other similar test, the company says.
In fact, the most promising way is to use exhalation tests as a quick screening tool – a more accurate version of not-very-reliable temperature monitors that became common during the pandemic, said Dr. Lamb. “They don’t really give you a diagnosis,” he said, referring to breath tests. “They give you a biochemical pattern that is consistent with the disease.”
InspectIR hopes to lease the analyzers to other companies, including healthcare facilities and companies operating mobile or pop-up test sites. They could be used to test travelers at airports or workers in an office building, the co-founders said, adding that there has already been interest from professional sports leagues and companies in the travel industry.
“Wherever they do a nose job more than once a day, we fit in well,” said Tim Wing, a co-founder of the company.
The device’s pricing has not yet been finalized, but co-founders said Friday they hope to offer licenses or subscriptions that translate to a price of around $ 10 to $ 12 per share. test.
“Yesterday was a huge domino for us,” said Mr. Wing Friday, the day after the device was approved. “Not all of these things are ready to go, defined yet.”
The company said it had raised $ 2.7 million to date and that Pfeiffer Vacuum would be its first production partner.