(Bloomberg) -- AstraZeneca Plc sued in London to block a former top dealmaker from sharing key therapy information with his new employer GSK Plc, saying Chris Sheldon was in danger of breaching a non-compete agreement. 

Sheldon, who was one of AstraZeneca’s most senior employees, is set to start at GSK in September. The executive had access to confidential information in a whole host of sensitive areas including the firm’s cancer work, AstraZeneca said in a legal filing. He was paid more than £644,000 ($774,090) in shares in 2021 to sign the non-compete clause.

GSK poached Sheldon and another senior dealmaker to boost its pipeline of cancer therapies and other drugs. Sheldon was tasked with identifying late-stage deal opportunities as the pharmaceutical giant looks for ways to reignite growth in its drug business.

AstraZeneca has previous for heading to court to protect its interests after a senior executive left for a a close rival. In 2017 it sued former executive Luke Miels who also moved to GSK. 

Sheldon declined to comment. He is yet to file his response to the London lawsuit. He’d offered not to work for GSK in respect of its oncology therapy area before a trial in late October, AstraZeneca said.

GSK declined to comment on the litigation. Astra didn’t immediately respond to a request for comment.

Astra has made a big push in the cancer field in recent years and has a potential new blockbuster drug with Enhertu, a therapy it’s co-developing with Japan’s Daiichi Sankyo Co. Trial results for this drug prompted a rare standing ovation at a key American medical oncology conference last June. 

Meanwhile GSK, which recently spun off its consumer health-care unit, is trying to revamp its drug pipeline which has stagnated in recent years. Last week GSK suffered a large investor sell off over fears it could have to pay out billions as lawsuits against an antacid it developed, called Zantac, mount.

Sheldon signed the non-compete in 2021, agreeing not to “facilitate competition” in respiratory, oncology and Covid-19-related therapy work for six months after leaving the firm, AstraZeneca said. 

He started at AstraZeneca as a research scientist and eventually became global head of business development and licensing for oncology research and development, his LinkedIn profile shows. 

The executive “was required to act as a bridge” between the oncology research teams and AstraZeneca’s commercial functions, before becoming the head of investor relations, AstraZeneca said.

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