Troubled biotech firm Theranos Inc. has reportedly told regulators that two years of results from its blood-testing machines have been voided, meaning that tens of thousands of patients could have been given incorrect results.

The company and its founder Elizabeth Holmes were once the darlings of investors, earning a valuation of $9 billion in 2014 on the back of claims that new technology in their Edison brand machines would revolutionize medical testing. But federal regulators have found major problems at Theranos’ California laboratory, and are considering banning Holmes from being involved in lab tests for two years.

The Wall Street Journal, which first raised questions over the accuracy of testing by the company last year, reports that Theranos has told health care regulator the Centers for Medicare and Medicaid Services that all Edison test results from 2014 and 2015 have been thrown out.

The company is issuing corrected results of tests conducted up to two years ago to doctors and patients, who may have already based clinical decisions on the initial tests, the Journal said, citing a person familiar with the matter and several doctors around the U.S.

The company, which handles almost 900,000 tests a year, announced in late March that it had undertaken a comprehensive review and “voided results associated with any findings that were not consistent with the quality standards the lab holds itself to today, under our lab’s new leadership.”

[WSJ]

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Write to Simon Lewis at simon_daniel.lewis@timeasia.com.