SAN DIEGO – Adults and children as young as 6 months old can now determine whether their symptoms like fever, cough and congestion are due to COVID-19, the flu or respiratory syncytial virus with a single test.
The Flowflex Plus 4-in-1 test, developed by ACON Laboratories Inc., is the first at-home test cleared by the U.S. Food and Drug Administration that screens for COVID, RSV and influenza A and B.
The test became available through retail pharmacies like CVS and Walgreens and grocery stores owned by Kroger and Albertson’s last month and can provide results in just 15 minutes from a single nasal swab sample.
“The COVID pandemic really opened up a new paradigm at the FDA of allowing people to test for more things at home, trusting the to take care of their health,” said ACON Vice President of Sales and Marketing Michael Lynch. “That’s really an important part of our mission right now is continuing to develop tests that will make it easier for people to monitor their health at home and get the appropriate medical attention as needed.”
‘On Shoulders’ of Previous Products
ACON has produced at-home COVID antigen tests since the FDA’s 2023 approval of the company’s first Flowflex test. The agency would later grant 510(K) clearance last year to ACON’s Flowflex diagnostic test for both COVID and flu A and B, deeming it safe and effective based on its substantial equivalence to tests that were already approved.
The company still had to re-establish its COVID and flu testing efficacy in its submission for approval of the Flowflex Plus 4-in-1 test, according to Lynch, which took longer than the company intended to collect enough samples of flu B, in particular.
“It allowed us to leverage some of our previous R&D as far as the assay development, because we had already developed not just the COVID antigen test but then the COVID plus flu A and flu B test,” Lynch said of the development process. “We were standing on the shoulders of those previous products and adding RSV to it.”
Most people infected with RSV will only experience common cold symptoms such as a fever, cough and runny nose, and the illness’ symptoms typically overlap with those of the flu and COVID-19.
Young children, older adults, people with heart and lung disease and people who are immunocompromised have a higher risk of developing a severe infection from RSV, and the virus is the leading cause of hospitalization among infants in the U.S., according to the Centers for Disease Control and Prevention.
‘Right Company’ at ‘Right Point of Time’
ACON was founded in 1996 in Bethlehem, Pennsylvania, but the company moved its headquarters to San Diego in 1999 with a focus on developing rapid lateral flow tests for things like drugs of abuse and fertility and pregnancy.
The lateral flow division of the company was acquired in the mid-2000s by what was then known as Inverness Medical Innovations and has since rebranded as Alere, a subsidiary of the multinational medical devices and health care company Abbott Laboratories, which also produces at-home tests for COVID and the flu.
ACON would go on to develop and produce tests for urine analysis, blood glucose monitoring and other diagnostic purposes before it re-entered the lateral flow testing market shortly before the start of the COVID pandemic.
“I would say we were really the right company at the right point in time,” Lynch said.
“We’ve got an amazing R&D team here in San Diego to do assay development, we’ve got extensive experience scaling up massive production, so we were able to uniquely respond when the global need arose, and since then we’ve continued to innovate, continued to bring additional home respiratory tests to the market.”
The company currently manufactures many of its testing products in-house at its 750,000-square-foot facility in San Diego, and also maintains a manufacturing facility in Hangzhou, China, and a distribution facility in Tijuana.
According to Lynch, ACON was able to “hit the ground running” with manufacturing once the FDA cleared Flowflex Plus 4-in-1 late in 2025, but the company is likely to see its first significant increase in use during the next flu and respiratory virus season later in 2026.
“We’re moving from what maybe three or four years ago was panic-driven testing into just a normalization of testing when you’re sick,” Lynch said. “This is what you do when your kids are sick, this is what you do when you’re going to be around grandma and grandpa and you don’t want to take flu or RSV to them, you test before you go, so this is just a normalization of incorporating testing into our lives in a rational, measured way.”
ACON Laboratories Inc.
FOUNDED: 1996
CEO: Lin Jixun
HEADQUARTERS: San Diego
BUSINESS: Diagnostic and medical devices
EMPLOYEES: Around 100 (San Diego headquarters)
WEBSITE: aconlabs.com
CONTACT: [email protected]
NOTABLE: ACON was originally founded in Bethlehem, Pennsylvania, before moving its headquarters to San Diego in 1999.
Eli is an award-winning reporter primarily covering the tech and life sciences industries. He previously worked as the San Diego City Hall reporter for the regional wire City News Service. He has also covered public health, transportation and state and local politics in the San Francisco Bay Area for Local News Matters, the nonprofit arm of the regional wire Bay City News Service, where he also oversaw the development and daily content management of the outlet’s public health and COVID-19 news and resource webpage. He is also a contributing writer covering Minor League Baseball for the analysis and commentary website Baseball Prospectus. Eli is a graduate of San Francisco State University and a native of Northern California.
