Xilio Therapeutics, Inc. entered into an exclusive license agreement with Gilead Sciences, Inc. (Gilead) for Xilio?s tumor-activated IL-12 program, including XTX301. Under the terms of the agreement: Xilio will receive $43.5 million in upfront payments, including a cash payment of $30.0 million and an initial equity investment by Gilead of $13.5 million in Xilio common stock at a purchase price of $1.97 per share. Xilio will be eligible to receive up to $604.0 million in additional contingent payments, including proceeds from up to three additional equity investments by Gilead, a $75.0 million transition fee and specified development, regulatory and sales-based milestones.

Xilio will also be eligible to receive tiered royalties ranging from high single digits to mid-teens on annual global net product sales. Prior to the potential transition fee, Xilio is eligible to receive up to a total of $29.0 million in additional equity investments and a development milestone payment. Xilio will be responsible for conducting clinical development for XTX301 in the ongoing Phase 1 clinical trial through dose expansion.

Following the delivery by Xilio of a specified clinical data package for XTX301, Gilead can elect to transition responsibilities for the development and commercialization of XTX301 to Gilead, subject to the terms of the agreement and payment by Gilead of the $75.0 million transition fee. If Gilead elects not to transition responsibilities for development and commercialization of the licensed products and pay the transition fee, then the license agreement will automatically terminate.