By Caroline Humer

NEW YORK, May 29 (Reuters) - Bristol-Myers Squibb has sued a top cancer immunotherapy executive for violating confidentiality and non-compete agreements after he left for direct competitor AstraZeneca, court documents show.

The suit, filed in Delaware's Court of Chancery late on Thursday, said that David Berman violated agreements that prevented him from using confidential and trade secret information when he accepted a job at AstraZeneca, which is also developing treatments that use the immune system to fight cancer.

Berman, who worked at Bristol for 10 years on immunotherapy-based cancer drugs, including Yervoy and the recently launched Opdivo, also broke non-compete agreements that were part of incentive pay packages, Bristol said.

The company said that Berman had agreed not to work at a competitor on related business for 12 months.

Berman, who was responsible for clinical development of Bristol's early stage immuno-oncology medicines and was connected to the clinical development of its entire immuno-oncology portfolio, resigned in writing on May 26, saying that he was headed to AstraZeneca's oncology division, according to the court documents. He had told his supervisor on May 20 of his plans to leave, the documents said.

He was the leader on research and development of Bristol-Myers immunotherapy cancer treatments and had access to non-public information about the company's drug pipeline strategies, the documents said.

Berman, who held the title of vice president and leader of Bristol's Immuno-oncology Exploratory Development Team, was not immediately reachable by phone or through his LinkedIn social media account. Documents identified him as living in Princeton, New Jersey.

AstraZeneca declined to comment.

According to the suit, Bristol and AstraZeneca are directly competing on the development of treatments based on the receptor proteins found on T-cells and in particular, the programmed death receptor, commonly referred to as PD-1.

Bristol has asked the court to prevent Berman from working for AstraZeneca for twelve months and to prevent him from using the company's confidential information at any time.

Bristol-Myers spokeswoman Laura Hortas said in a statement that the company "is committed to protecting the confidentiality of proprietary information about its leading immuno-oncology portfolio and business."

(Reporting by Caroline Humer, additional reporting by Sharon Begley; editing by Diane Craft)