The former CEO of Magellan Diagnostics pleaded guilty on Monday to a criminal charge related to a malfunction in the company’s lead-testing devices that produced inaccurately low results for tens of thousands of patients.

Amy Winslow was the last of three former Magellan executives indicted in 2023 over the malfunction to strike a deal to plead guilty rather than proceed to trial next month in federal court in Boston.

She agreed to plead guilty to a single count in the indictment that charged her with violating the Food, Drug and Cosmetic Act by introducing misbranded medical devices into interstate commerce with the intent to mislead.

That charge related to allegations that after Magellan discovered the malfunction, it sent customers a letter in 2014 that Winslow edited to advise them to incubate blood samples for 24 hours before using one of its lead-testing devices.

Prosecutors said those instructions were contrary to the device’s label, which promised immediate, accurate results without any incubation, and were altered without first notifying the U.S. Food and Drug Administration as required.

Prosecutors have agreed to recommend that Winslow be sentenced to a year and a day in prison and a $10,000 fine and to drop various fraud charges against her. Her sentencing was set for July 23.

Winslow’s lawyer did not respond to requests for comment.

Massachusetts-based Magellan, now owned by Ohio-based Meridian Bioscience, in May agreed to pay $42 million and plead guilty to resolve related charges concerning the reliability of devices it sold for detecting lead levels and lead poisoning in the blood of children and adults.

The malfunction was discovered in 2013 and affected three testing devices in Magellan’s LeadCare line, including one that accounted for more than half of all blood lead tests conducted in the U.S. between 2013 and 2017, according to prosecutors.

Prosecutors said Winslow and her co-defendants never reported the issue to the FDA and only notified the agency after Meridian had acquired the company for $66 million in 2016. A recall was launched in 2017.

Prosecutors have also recently reached plea deals with Hossein Maleknia, Magellan’s former chief operating officer, and Reba Daoust, the company’s former manager and director of quality assurance and regulatory affairs.

(Reporting by Nate Raymond in Boston; Editing by Richard Chang)