A married scientist couple have pleaded guilty to taking confidential data from a Pfizer lab where she worked and sending it to China where her husband was trying to develop a cancer vaccine.

Federal prosecutors say the scheme was called off after husband Chenyan Wu was caught smuggling five suitcases filled with toxic chemicals into the United States after shutting down his lab near Shanghai and having him transferred to the United States.

“These are serious computer fraud and smuggling crimes,” said Randy Grossman, the U.S. attorney for the Southern District of California. “An accused failed to protect her employer’s confidential and important research and instead used it for her and her husband’s benefit. To compound the harm, the other defendant put travelers at risk by illegally transporting the hazardous chemicals from his lab to the United States.

Wu pleaded guilty to smuggling goods and faces up to 20 years in prison when convicted. Chen admitted to committing computer fraud and faces a year in prison.

Wu, 58, had previously worked for Pfizer PFE,
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in a lab in the UK, but left in 2010, according to court documents. He then moved to China to start his own lab, TheraMab, which focused on mRNA vaccine research.

At the same time, his wife, Lianchun Chen, 51, started working for Pfizer in a lab near San Diego. Prosecutors say that over the next few years she sent copies of Pfizer’s mRNA research and sent it to her husband in China.

Messenger RNA, or mRNA, is the core technology behind Pfizer’s blockbuster COVID-19 vaccine, which it developed in partnership with Germany’s BioNTech BNTX,
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The Pfizer-BioNTech vaccine was the first mRNA product licensed and approved by the Food and Drug Administration. Pfizer expects to generate $32 billion from the vaccine in 2022. Researchers have also been working on targeting cancer with this technology.

Cases of theft of pharmaceutical trade secrets have become increasingly common in recent years. The former director of the immuno-oncology division at Merck MRK,
+1.55%
was charged in January 2021 with stealing proprietary research. Last July, a husband-wife couple of researchers for Roche Holding’s Genentech ROG,
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pleaded guilty to sending trade secrets to a startup overseas.

In February, Pfizer filed a lawsuit against two former researchers they accused of taking confidential information to start their own lab. The researchers’ company then counterattacked Pfizer, claiming that the pharmaceutical giant was simply seeking to smear a competitor’s reputation.

A message sent to Pfizer representatives was not immediately returned.

Wu’s attorney, Jeremy Warren, said his client admitted he made a mistake.

“Dr. Wu is an American citizen and a diligent scientist who seeks to help people. He has never had any problems before in his life and regrets what he has done,” Warren said.

Chen’s attorney did not immediately respond to a message seeking comment.

In 2021, Wu – facing a halt in funding for his lab by the Chinese government – ​​decided to shut it down and move to the United States.

He then packed the contents of his lab into five suitcases and returned to the United States on a Delta flight via Seattle-Tacoma International Airport, where he planned to get a connection to San Diego where his wife lived.

Prosecutors say Wu did not declare he was carrying chemicals or commercial materials on his customs form, but when his bags were searched in Seattle, officers found nearly 1,000 vials of chemicals. While most were common laboratory chemicals, some were marked as hazardous and deadly if inhaled. The discovery prompted authorities to call a Hazmat team to the airport, according to court documents.

According to court documents, when asked about the vials, Chen said China had onerous rules about transporting these materials, so he chose to “take a gamble to be honest.”

By this point, investigators had already begun investigating Wu after finding a Powerpoint presentation from his lab on the phone of a defendant who had pleaded guilty to violating export controls.