Xilio Therapeutics, Inc.

In July 2023, the Company and F. Hoffmann-La Roche Ltd (“Roche”) entered into a clinical trial collaboration pursuant to a clinical supply agreement to evaluate vilastobart in combination with atezolizumab (Tecentriq®) in a Phase 1/2 clinical trial consisting of Phase 1 dose escalation assessing the combination in patients with advanced solid tumors and Phase 2 assessing the combination in patients with microsatellite stable metastatic colorectal cancer.

Under the clinical supply agreement, the Company is eligible to receive specified cost-sharing payments from Roche, and each company will supply its respective anti-cancer agent to support the Phase 1/2 clinical trial. As of September 30, 2025, the Company has received $8.0 million in total cost-sharing payments from Roche. The Company is responsible for conducting the Phase 1/2 clinical trial and retains global development and commercialization rights to vilastobart.

The Company concluded that the cost-sharing payments under the clinical supply agreement are not in the scope of ASC 606 because the Company does not consider performing research and development services for reimbursement to be part of its ongoing major or central operations. Therefore, the Company applied a reasonable, rational, and consistently applied accounting policy election to record the cost-sharing payments under the clinical supply agreement as a reduction of research and development expenses in the condensed consolidated statements of operations and comprehensive loss for the period in which a study development event is achieved. The Company did not recognize a reduction of research and development expense during each of the three months ended September 30, 2025 and 2024. The Company recognized a reduction of research and development expense of $2.0 million during each of the nine months ended September 30, 2025 and 2024.