Welcome to our dedicated page for Xilio Therapeutics SEC filings (Ticker: XLO), a comprehensive resource for investors and traders seeking official regulatory documents including 10-K annual reports, 10-Q quarterly earnings, 8-K material events, and insider trading forms.
Xilio Therapeutics, Inc. filings document the regulatory record of a clinical-stage biotechnology company developing masked immuno-oncology therapies. Its 8-K reports cover financial results, pipeline and business updates, investor presentations, material agreements, capital-structure matters, and clinical or regulatory disclosures tied to its masked I-O programs.
Proxy statements and related 8-K filings describe stockholder votes, director elections, board and committee changes, auditor ratification, equity incentive plans, and amendments affecting common stock. The filing record also includes disclosures related to reverse stock split matters, security-holder rights, director compensation, and governance arrangements for the company’s Delaware corporate structure.
Xilio Therapeutics, Inc. filed an initial insider ownership report for director Cheryl R. Blanchard. This Form 3 identifies her status as a director of the company but shows no reported stock transactions or derivative positions at the time of filing.
Xilio Therapeutics, Inc. reported a board change and related director compensation details. On April 15, 2026, the board elected Cheryl R. Blanchard, Ph.D. as a Class III director with a term running through the 2027 annual meeting, and appointed her chair of the Compensation Committee and a member of the Audit Committee.
She will receive an annual cash fee of $40,000 for board service, plus $12,000 as Compensation Committee chair and $7,500 as an Audit Committee member. She will also receive an initial option to purchase 10,000 shares, vesting over three years, and become eligible for annual options to purchase 5,000 shares after six months of service. Each option will carry an exercise price equal to the Nasdaq closing price on the grant date and a ten-year term.
Dr. Blanchard replaces Christina Rossi, who resigned from the board and all committees effective April 15, 2026. The company states that Ms. Rossi’s resignation did not result from any disagreement with the company or its management.
Xilio Therapeutics, Inc. director Shannon James Samuel completed an open-market purchase of common stock. On March 26, 2026, Samuel bought 5,000 shares at a weighted average price of $8.79 per share, increasing direct holdings to 10,000 shares. The reported ownership reflects a 1-for-14 reverse stock split effective March 13, 2026.
Xilio Therapeutics, Inc. is a clinical-stage biotechnology company focused on masked immuno-oncology therapies that activate mainly inside tumors to improve cancer outcomes while limiting side effects. The company implemented a 1‑for‑14 reverse stock split of its common stock on March 13, 2026.
Xilio’s pipeline includes XTX501, a bispecific PD‑1/masked IL‑2 antibody fusion protein expected to enter Phase 1 after an IND filing targeted for mid‑2026, and two wholly owned masked T‑cell engager programs directed at PSMA/STEAP1 and CLDN18.2 with planned IND submissions in 2027. Efarindodekin alfa, a masked IL‑12, showed early anti‑tumor activity and tolerability in Phase 1 and is in an ongoing Phase 2 trial.
The company has major collaborations: with Gilead for efarindodekin alfa and other IL‑12 molecules, with up to $575 million in potential milestones plus royalties, and with AbbVie on up to four masked immunotherapy programs, with up to about $2.1 billion in potential contingent payments plus royalties. As of June 30, 2025, non‑affiliate common stock held an aggregate market value of about $34.9 million, and 5,782,511 shares were outstanding as of March 18, 2026.
Xilio Therapeutics reported much stronger 2025 results driven by collaboration revenue and new financing, while outlining progress across its masked immuno-oncology pipeline. Collaboration and license revenue rose to $43.8 million in 2025 from $6.3 million in 2024, mainly from AbbVie and Gilead agreements.
Research and development spending increased to $56.0 million as the company advanced XTX501 and multiple masked T cell engager programs, and net loss narrowed to $35.0 million from $58.2 million. Cash and cash equivalents were $137.5 million as of December 31, 2025, and Xilio expects this to fund operations through the end of 2027.
Xilio Therapeutics is implementing a 1-for-14 reverse stock split of its common stock, effective at 5:00 p.m. Eastern Time on March 13, 2026. Every fourteen issued and outstanding shares will be automatically reclassified into one share, with cash paid instead of fractional shares.
The company expects its common stock to begin trading on a split-adjusted basis on March 16, 2026 under the existing symbol XLO. The reverse split will not change the number of authorized shares or the par value but will reduce outstanding shares from approximately 73.5 million to approximately 5.2 million. A key aim is to help regain compliance with the Nasdaq Capital Market minimum bid price requirement.
Xilio Therapeutics is sharing an updated investor presentation highlighting its tumor‑selective immuno‑oncology pipeline, strategic partnerships and cash position. The company reports an estimated $137 in cash and cash equivalents as of December 31, 2025, plus $40M in gross proceeds from a February 2026 follow‑on offering and a cash runway through the end of 2027.
The presentation emphasizes wholly owned and partnered programs, including bispecific PD‑1/masked IL‑2 candidate XTX501, masked T cell engagers targeting PSMA+STEAP1 and CLDN18.2, masked IL‑12 efarindodekin alfa with Gilead, and masked anti‑CTLA‑4 vilastobart. Xilio outlines potential additional funding sources, including up to $36 in gross proceeds from Series C warrant exercises and a $75M option fee if Gilead licenses the IL‑12 program, alongside milestones with AbbVie and Gilead through 2027.
Xilio Therapeutics, Inc. reported that its stockholders approved an amendment to its restated certificate of incorporation to authorize a reverse stock split of its common stock. The reverse split may be implemented at a ratio between 1-for-2 and 1-for-30, at the sole discretion of the board of directors.
The proposal passed with 55,438,144 votes for, 1,521,271 against and 33,539 abstentions. Stockholders also approved a proposal to adjourn the special meeting if needed to obtain sufficient votes, with 55,461,067 votes for, 1,491,733 against and 40,154 abstentions.
GILEAD SCIENCES, INC. reported open-market purchase transactions in a Form 4 filing for XLO. The filing lists transactions totaling 3,739,000 shares at a weighted average price of $0.53 per share. Following the reported transactions, holdings were 40,384,266 shares.
Bain Capital Life Sciences–affiliated funds report a significant but capped stake in Xilio Therapeutics, Inc. As of the close of business on December 31, 2025, they collectively beneficially owned 7,372,686 shares of Xilio common stock, equal to 9.99% of the outstanding shares.
The holdings include 992,111 shares held by Bain Capital Life Sciences Fund II, L.P. and 120,833 shares held by BCIP Life Sciences Associates, LP, plus a pre-funded warrant held by BCLS II Equity Opportunities, LP to purchase 15,627,441 shares. Because of a 9.99% “Beneficial Ownership Blocker,” only 6,259,742 warrant shares are counted in current beneficial ownership.
This percentage is calculated using 67,540,930 Xilio shares outstanding, as reported in a Form 8-K, together with the warrant shares counted under the blocker. The group certifies that the securities are not held with the purpose or effect of changing or influencing control of Xilio.