InspectIR Nabs First FDA Approval for a SARS-CoV-2 Breathalyzer

It turns out that the concept of detecting the SARS-CoV-2 virus from a breath sample is not just a bunch of hot air. On April 14, the U.S. Food and Drug Agency (FDA) announced that, for the first time, it has granted Emergency Use Authorization (EUA) for a COVID-19 breathalyzer test.

The Search for a New COVID-19 Testing Modality

There are three types of SARS-CoV-2 tests currently on the US market: Polymerase chain reaction tests, serology tests, and antigen tests. PCR tests, which detect genetic material from the virus, are the most accurate but require extensive preparation that makes them less than ideal for use at the point of care. Serology tests detect SARS-CoV-2 antibodies while antigen tests that detect antigens secreted by those antibodies deliver rapid results at relatively low costs, but lack the accuracy of PCR tests. Breathalyzer tests are a new modality that rely on a different biomarker for virus detection: volatile organic compounds (VOCs) expelled by the lungs. In addition to offering greater accuracy and speed, breathalyzer tests are less invasive than current SARS-CoV-2 rapid tests that rely on lung tissue samples collected by swabs. Researchers and test companies around the world have been furiously working to develop COVID-19 breathalyzers. But while a few have reached European and Asian markets, the FDA has yet to approve a breath-based COVID-19 in the US, until now.

The InspectIR COVID-19 Breathalyzer

InspectIR, a Texas-based developer of portable opioid and cannabis detection devices, has scored the first EUA for a COVID-19 breathalyzer. Dubbed the InspectIR COVID-19, the device uses a technique called gas chromatography-mass spectrometry (GC-MS) to separate and identify five VOCs associated with SARS-CoV-2 in exhaled breath. Patients breathe into a disposable straw on the device, which is roughly the same size as a piece of carry-on luggage, with results provided in less than three minutes. The test is intended for health care settings where samples can be collected and analyzed, such as mobile testing sites, doctor's offices, and hospitals. InspectIR expects to be able to produce approximately 100 instruments per week, which can each be used to evaluate approximately 160 samples per day. At this level of production, testing capacity using the InspectIR COVID-19 Breathalyzer is expected to increase by approximately 64,000 samples per month. In granting EUA, the FDA relied on a study performed in 2,409 people in four states, some of whom had COVID-19 symptoms and some of whom did not. According to the agency, the breathalyzer test had a sensitivity of 91.2 percent (90 percent CI 85.4-94.8) and specificity of 99.3 percent (95 percent CI 98.8-99.5) as compared to a PCR test, yielding a negative predictive value of 99.6 percent. Translation: People who receive a negative test result are likely truly negative in areas of low disease prevalence, the FDA press release notes. The results were similar in a follow-up trial of 12 symptomatic individuals that the company performed in Texas during the February Omicron surge, with a sensitivity of 90.9 percent (90 percent CI 67.7-98.0).

FDA Issues Caveat on Interpreting Breathalyzer Results

Despite the confirmatory evidence of the InspectIR COVID-19 Breathalyzer’s sensitivity and sensibility, the FDA cautions against treating test results as conclusive. A test that does detect SARS-CoV-2 VOCs should be considered a presumptive (unconfirmed) positive test result and be confirmed with a molecular test, the agency says. Negative results do not rule out SARS-CoV-2 infection and should not be used as the sole basis for treatment or patient management decisions, including infection control decisions. The agency calls on practitioners to consider a negative result in the context of a patient’s recent exposures, history, and the presence of clinical signs and symptoms consistent with COVID-19.

More SARS-CoV-2 Breathalyzers in the Pipelines

The SARS-CoV-2 breathalyzer is likely to be the next big thing in COVID-19 diagnostics. Other breathalyzer projects in the US and around the world to keep an eye on:

• The National Aeronautics and Space Administration (NASA) is testing a prototype of a COVID-19 breathalyzer device called E-Nose originally developed by Tennessee subcontractor Variable Inc. to measure air quality inside a spacecraft (See, Diagnostic Testing and Emerging Technology, May 22, 2021);
• Canary Health Technologies and Divoc Laboratories are collaborating to develop and validate a handheld digital breath test called ASU Detect CV19, which uses cloud-based artificial intelligence technology to detect the SARS-CoV-2 virus in less than three minutes (See, Laboratory Industry Report, February 22, 2021);
• Singapore startup Silver Factory Technology has begun testing a SARS-CoV-2 breathalyzer at Singapore Changi Airport and plans to build a facility to mass produce the device; and

Breathonix, another Singapore firm, which was spun off from the National University of Singapore, began testing its own SARS-CoV-2 breath test at a busy bridge checkpoint in Malaysia that is used to test hundreds of incoming truck drivers a day.