Blood-testing startup Theranos started from a useful idea: why are we all carrying around tiny phonecomputers in our pockets, while the basic technology behind lab tests hasn’t changed much? The company developed new equipment that uses only a few drops of blood to run standard lab tests. The startup was worth billions, and partnered wtih Walgreens for in-store blood testing centers. Then it ran into a tiny problem with health regulators: the new tests didn’t work as well as advertised.

The company told the Centers for Medicare and Medicaid Services, which found serious problems with the company’s equipment and test results during an inspection last year, that it went back and sent revised test results to patients and their doctors for tests performed in 2014 and 2015. Some results were revised, while the company told patients that others were invalid.

Yes, those patients may have made medical decisions based on flawed test results. Corrected test results included tests run on the company’s proprietary Edison machine that uses tiny quantities of blood, and tests run with standard amounts of blood on equipment purchased from other companies.

The Wall Street Journal cites “persons familiar with the matter” who say that the company was using the machine it had developed for only about a dozen of the 200 tests it offers, and stopped using its own equipment at its lab in Newark, CA back in June of 2015.

The Centers for Medicare and Medicaid Services has threatened severe sanctions against the company, including banning founder Elizabeth Holmes from the the industry for years, and pulling the license of the company’s lab in California.

Theranos Voids Two Years of Edison Blood-Test Results [Wall Street Journal]

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