Xilio Therapeutics reports $43.8M revenue, extends cash runway to 2027
Biotech company leverages AbbVie collaboration and Gilead milestone to fund pipeline expansion through 2027
Xilio Therapeutics reported collaboration and license revenue of $43.8 million for the full year 2025, a significant increase from $6.3 million in 2024, as the Waltham-based biotechnology company advanced its tumor-activated immunotherapy pipeline through strategic partnerships and milestone payments.
The company's cash position strengthened substantially to $137.5 million as of December 31, 2025, up from $55.3 million at the end of 2024. This increase was driven by $35.8 million in gross proceeds from Series B warrant exercises and a $17.5 million development milestone payment from Gilead in the fourth quarter. Xilio management indicated the cash runway extends through the end of 2027, providing operational flexibility for ongoing clinical programs.
Fourth quarter revenue reached $13.7 million, compared to $1.7 million in the same period of 2024, primarily reflecting revenue recognition under the AbbVie collaboration agreement and the Gilead milestone. Research and development expenses for the full year increased to $56.0 million from $41.2 million in 2024, largely attributable to manufacturing activities for IND-enabling studies and preclinical development of XTX501, the company's bispecific PD-1/masked IL-2 program.
On the pipeline front, Xilio announced that XTX501 remains on track for an Investigational New Drug submission in mid-2026, with Phase 1 trial initiation planned for the second half of 2026. The therapy will initially be evaluated in metastatic non-small cell lung cancer. The company also advanced a wholly-owned masked T cell engager program targeting CLDN18.2, with new preclinical data scheduled for presentation at the American Association for Cancer Research Annual Meeting in April 2026.
Xilio's efarindodekin alfa (XTX301), a masked IL-12 therapy, continues in Phase 2 evaluation for patients with advanced solid tumors. The company expects to deliver an option data package to partner Gilead Sciences in the first half of 2027. Earlier in 2025, Xilio had presented encouraging Phase 2 data for vilastobart (XTX101) in combination with atezolizumab, showing a 27% objective response rate in metastatic microsatellite stable colorectal cancer patients without liver metastases.
The stock gained 7.8% to $7.86 in morning trading on March 23, 2026, reflecting investor optimism about the extended cash runway and pipeline progress. The shares remain below their 52-week high of $16.52, with the company having implemented a 1-for-14 reverse stock split in March 2026 to maintain compliance with Nasdaq's minimum bid price requirement.
Analysts at major firms have maintained a positive outlook on Xilio's prospects, noting the company's strong balance sheet provides multiple paths to value creation through its tumor-activated approach. The biotechnology firm's strategy of developing masked immunotherapies that activate specifically within the tumor microenvironment aims to improve safety profiles compared to conventional immuno-oncology treatments.
Xilio's multi-specific masked T cell engager program targeting PSMA and STEAP1 with co-stimulatory signaling remains in development, with a development candidate nomination anticipated in the second quarter of 2026. IND applications for the masked T cell engager programs are planned for 2027, positioning the company for a sustained clinical development timeline through the remainder of the decade.