The Silicon Valley startup told federal health regulators at the Centers for Medicare and Medicaid Services that it had voided results from 2014 and 2015 generated by its testing devices, the Wall Street Journal reported. Theranos spokeswoman Brooke Buchanan confirmed the report by e-mail.

“Excellence in quality and patient safety is our top priority and we’ve taken comprehensive corrective measures to address the issues CMS raised in their observations,” Buchanan said in an e-mail. “As these matters are currently under review, we have no further comment at this time.”