Theranos shuts down labs, wellness centers, lays off more than 300 workers

Theranos will cut hundreds from its workforce and close several facilities, company founder and CEO Elizabeth Holmes announced in an open letter Wednesday.

Holmes said the company will close its clinical labs and Theranos Wellness Centers, which means 340 employees in Arizona, California and Pennsylvania are now out of a job.

[Also: Theranos appeals sanctions]

"We are profoundly grateful to these team members, many of whom have devoted years to Theranos and our mission, for their commitment to our company and our guests," Holmes said in the letter.

As the company struggles under controversy and looming sanctions, Holmes said Theranos will "return our undivided attention" to their mini-lab platform, a small testing unit which is designed to process small capillary whole blood and plasma samples using the company's capillary blood collection devices.

The device has yet to be cleared by the FDA.

[Also: Embattled Theranos founder banned from blood-testing business for 2 years]

"Our ultimate goal is to commercialize miniaturized, automated laboratories capable of small-volume sample testing, with an emphasis on vulnerable patient populations, including oncology, pediatrics, and intensive care," Holmes said.

In August, the embattled blood testing company filed a notice of intent to appeal the sanctions that the Centers for Medicare and Medicaid Services had imposed on their Newark, California lab.

A month earlier, the Centers for Medicare and Medicaid Services banned Holmes from the blood testing business for two years and issued a number of other sanctions in response to Theranos' alleged failures including a limitation of the laboratory's CLIA certificate for the specialty of hematology; a civil monetary penalty; a plan of correction; suspension of the laboratory's approval to receive Medicare and Medicaid payments for any services performed for the specialty of hematology; and cancellation of the laboratory's approval to receive Medicare and Medicaid payments for all laboratory services.

Twitter: @BethJSanborn