"It’s a milestone for us," said Elizabeth Holmes, Theranos' chief executive. "It demonstrates the quality and integrity of our work."
The herpes test, which costs $9.07, is one of more than 100 the company sells for less than $10. (Holmes said a more traditional herpes blood test would cost about $175.) The tests currently are sold at 42 Walgreens in Arizona and one store in California.
This comes at a time when Theranos has been pummeled by some academic researchers because of the secrecy about how its technology works. Several scientists have said that fundamental questions about how its technology compares to other products on the market have gone unanswered.
"Their claims of superiority over current systems and practices are speculative, at best," Eleftherios Diamandis, of Mount Sinai Hospital in Toronto, wrote in a paper published last month in the journal Clinical Chemistry and Laboratory Medicine. "An open discussion of the merits and shortcomings ... should take place in the scientific literature and other public forums, so that the benefits and harms are better understood by the public."
John Ioannidis, chairman of disease prevention at Stanford University, wrote a critique of Theranos' lack of transparency and what he called "stealth research" in the Journal of the American Medical Association in February.
"I think that getting FDA clearance is a step in the right direction and Theranos should be congratulated for doing this," Ioannidis wrote in an e-mail. "However, I still believe that it is important also to have the full information available in the scientific community through peer-reviewed publications on methods and results, with access of other scientists to the raw data and protocols."
The FDA approval may help answer some of the questions surrounding Theranos. The company said it provided the agency with extensive information about its technology. It also shared with federal officials the results of a study of 818 people showing the accuracy of its tests when compared with commercially available tests that use blood drawn from a vein, the company said. That data will become public next week, Holmes said.
Eric Lakin, a senior associate with DeciBio, a market research and strategy firm, said the FDA approval delivers a big boost of confidence to Theranos.
But what may be more essential to the company in the near term is an Arizona law that makes some of its tests easier to buy. Arizona already allowed consumers to buy some Theranos tests without a prescription. Starting Friday, all of their tests will fall under those rules.
“It basically empowers the individuals to own their own health, and I think it’ll bring about competition in laboratory pricing, making it dramatically less expensive,” Sen. John McCain (R-Ariz.), who supported the legislation, said in an interview.
Lakin called the FDA decision "an important step forward and a milestone in demonstrating their core technology can pass the scrutiny of the FDA.
"But I think you’re still going to have the scientific community wondering what the underlying technology is," he said. "It’s still a core question that hasn’t been answered."
The College of American Pathologists, an association of doctors who examine and interpret lab tests, said in a statement that it could not comment on the technology, since they had not reviewed it.
“Any laboratory using any FDA-approved test must validate it in their own environment," R. Bruce Williams, chairman of the College's Council on Scientific Affairs, said in a statement. "However, the ability to draw less blood and spend less resources to obtain an accurate laboratory result is a positive diagnostic achievement.”