FDA clears its first at-home blood test for syphilis

The FDA granted a green light to its first at-home, over-the-counter test to detect a person’s exposure to syphilis, offering a private option to help detect the sexually transmitted infection.

Developed by NOWDiagnostics, the First To Know rapid test captures antibodies in the bloodstream that can be linked to the bacteria behind the disease, delivering a result within about 15 minutes using a drop of blood from a fingerstick.

The FDA’s de novo clearance follows up on the authorization late last year of its first mail-in test for home-collected samples to screen for chlamydia and gonorrhea—the agency’s first at-home diagnostic kit for a sexually transmitted infection other than HIV.

“We continue to see advancements in tests, particularly tests for sexually transmitted infections, which can give patients more information about their health from the privacy of their own home,” said Michelle Tarver, M.D., Ph.D., acting director of the FDA’s Center for Devices and Radiological Health.

However, the NOWDx test alone cannot be used to officially diagnose a syphilis infection; a follow-up with a laboratory test is needed. Being an antibody test, it will return a positive result for a person who previously had an infection, even if they were successfully treated.

The FDA also said that people who know they have recently been exposed to syphilis should seek out a healthcare provider for treatment and evaluation regardless of the test’s result.

“Access to home tests may help increase initial screening for syphilis, including in individuals who may be reluctant to see their health care provider about possible sexually transmitted infection exposure,” Tarver said in an agency statement. “This can lead to increased lab testing to confirm diagnosis, which can result in increased treatment and reduction in the spread of infection.”

According to the Centers for Disease Control and Prevention, cases of syphilis in the U.S. rose 80% between 2018 and 2022 to more than 207,000 infections—with rates today being the highest in decades.

“FDA granting De Novo authorization of our First To Know Syphilis Test could not have come at a more important juncture in our country’s efforts to slow the rise of syphilis,” NOWDx CEO Rob Weigle said in a statement.

“Testing is one of the most important tools we have in preventing the spread of sexually transmitted infections, and for the first time ever, consumers now have a fast and simple syphilis test that can be performed in the privacy of one’s home, with a result in minutes,” Weigle said.

Earlier this year, the Department of Health and Human Services launched the National Syphilis and Congenital Syphilis Syndemic task force to respond to the rising number of infections. The FDA said the First To Know test’s clearance will aid the department’s strategic plan.

If left untreated, syphilis can damage the heart and brain, while also causing blindness, deafness or paralysis. During pregnancy, it can lead to miscarriage, lifelong medical issues or the death of the infant, the agency said.