** Shares of drug developer Xilio Therapeutics XLO.O more than double to $1.37 premarket

** AbbVie ABBV.N and XLO enters into collaboration and option agreement to develop cancer immunotherapies

** Under terms of the deal, XLO to receive $52 million in an upfront payment and will be eligible to receive up to about $2.1 billion in milestone payments

** Deal gives ABBV access to XLO's proprietary tumor-activation technology to develop new immunotherapies

** In the last 12 months, XLO has fallen 7%

(Reporting by Siddhi Mahatole)

((Siddhiprabhanjan.mahatole@thomsonreuters.com))