efarindodekin alfa (XTX301) / Xilio Therap, Gilead - LARVOL DELTA

Efarindodekin Alfa: Phase 1 Data in Patients with Advanced Solid Tumors…Presented at SITC (GlobeNewswire) - "As of a data cutoff date of September 2, 2025, 62 patients with advanced solid tumors had been treated....At dose levels up to the recommended Phase 2 dose (RP2D), efarindodekin alfa has been generally well-tolerated, and treatment-related adverse events were primarily Grade 1 or 2. Efarindodekin alfa also demonstrated encouraging anti-tumor activity, including two partial responses (PRs) in patients with advanced solid tumors consisting of a confirmed PR in a patient with HPV-negative head and neck squamous cell carcinoma (33% decrease in target lesions), with meaningful changes in pharmacodynamic (PD) biomarkers, and an unconfirmed PR in a patient with uveal melanoma (55% decrease in target lesions)."

P1 data • Squamous Cell Carcinoma of Head and Neck • Uveal Melanoma

Development Plans for Efarindodekin Alfa (GlobeNewswire) - "Xilio has completed enrollment in the Phase 1A monotherapy dose escalation and Phase 1B monotherapy dose expansion portions of the ongoing Phase 1/2 clinical trial, and evaluation of those patients is ongoing. In the third quarter of 2025, Xilio initiated dosing in the Phase 2 portion of the clinical trial evaluating efarindodekin alfa as a monotherapy in patients with certain advanced solid tumors."

Trial status • Solid Tumor

XTX301, a Tumor-Activated Interleukin-12 (IL-12), Demonstrated IL-12 Pharmacology in Patients with Advanced Solid Tumors: Pharmacodynamic Data from First-in-Human Phase 1 Study (NCT05684965) (SITC 2025) - P1/2 | "(C) Multiplex immunofluorescence: CD3+CD8+ cell density (cells/mm²) showed consistent elevation on-treatment across all tissue compartments compared to pre-treatment. Results demonstrate robust CD8+ T cell infiltration following XTX301 treatment"

Clinical • First-in-human • Metastases • P1 data • PK/PD data • Head and Neck Cancer • Oncology • Solid Tumor • CD8 • IFNG • IL12A

Xilio Therapeutics Announces Upcoming Presentations at the Society for Immunotherapy of Cancer (SITC) 40th Annual Meeting (GlobeNewswire) - "Xilio plans to present clinical data for vilastobart, a tumor-activated, Fc-enhanced, high affinity binding anti-CTLA-4, and efarindodekin alfa (XTX301), a tumor-activated IL-12, and plans to present preclinical data highlighting the company’s masked T cell engager programs."

P1/2 data • Preclinical • Colorectal Cancer

As of a data cutoff date of September 2, 2025, at dose levels up to the recommended Phase 2 dose (RP2D), efarindodekin alfa has been generally well-tolerated in Phase 1, and the majority of treatment-related adverse events were Grade 1 or 2 (Xilio Press Release) - "Based on these promising Phase 1 data, Xilio recently selected an initial RP2D and schedule for efarindodekin alfa and initiated patient dosing in the Phase 2 portion of the trial evaluating efarindodekin alfa as a monotherapy in patients with certain advanced solid tumors. In connection with the initiation of Phase 2, Xilio achieved a development milestone of $17.5 million."

Commercial • P1 data • Trial status • Solid Tumor

XTX301: tumor-activated IL-12 (GlobeNewswire) - "Xilio recently completed enrollment in Phase 1A monotherapy dose escalation and evaluation of those patients is ongoing. In addition, Xilio continues to enroll patients in Phase 1B monotherapy dose expansion of the ongoing Phase 1 clinical trial of XTX301."

Enrollment status • Solid Tumor

Xilio Therapeutics Announces Pipeline and Business Updates and First Quarter 2025 Financial Results (GlobeNewswire) - "R&D expenses were $8.3 million for the quarter ended March 31, 2025, compared to $10.4 million for the quarter ended March 31, 2024. The decrease was primarily driven by decreased clinical development activities for XTX202, a masked IL-2, as a result of discontinuing further investment in XTX202, decreased personnel-related costs due to lower headcount and decreased manufacturing costs for XTX301, partially offset by increased spending related to early stage programs and indirect research and development, increased clinical development activities for vilastobart and manufacturing activities for XTX501 in connection with IND-enabling studies."

Commercial • Colorectal Cancer • Oncology

Xilio Therapeutics Announces…Fourth Quarter and Full Year 2024 Financial Results (GlobeNewswire) - "R&D expenses were $8.8 million for the quarter ended December 31, 2024, compared to $11.7 million for the quarter ended December 31, 2023....The year-over-year decrease was primarily driven by decreased clinical development activities for XTX202, a masked IL-2, as a result of discontinuing further investment in XTX202, decreased spending related to early-stage programs and indirect research and development costs, decreased personnel-related costs and decreased manufacturing costs for XTX301, partially offset by increased clinical development activities for vilastobart and XTX301."

Commercial • Oncology • Solid Tumor

Pipeline and Business Updates: XTX301 (GlobeNewswire) - "A maximum tolerated dose has not yet been established, and Xilio continues to enroll patients in Phase 1A monotherapy dose escalation and Phase 1B monotherapy dose expansion of the ongoing Phase 1 clinical trial of XTX301."

Trial status • Solid Tumor

Preliminary Data from Ongoing Phase 1 Trial for XTX301 (IL-12) (GlobeNewswire) - P1/2 | N=358 | NCT05684965 | Sponosr: Xilio Development, Inc. | "Sustained interferon gamma (IFNɣ) signaling without evidence of tachyphylaxis throughout treatment cycles. Tachyphylaxis has historically limited other IL-12 agents. Evidence of dose-dependent pharmacology with T cell, natural killer (NK) cell and NKT cell proliferation. Consistent with the tumor-activated design of XTX301, no measurable activated XTX301 was detected in peripheral circulation across all dose levels and schedules. Across all dose levels and schedules, no Grade 4 or Grade 5 treatment-related adverse events (AEs) were reported by investigators and no patients experienced a dose limiting toxicity or a dose reduction due to a treatment-related AE. In addition, across all dose levels and schedules, the majority of treatment-related AEs were Grade 1 or 2..."

P1 data • Oncology • Solid Tumor

Xilio Therapeutics Announces Pipeline and Business Updates and Third Quarter 2024 Financial Results (GlobeNewswire) - "Xilio expects to report initial Phase 2 data for vilastobart in combination with atezolizumab in approximately 20 patients with MSS CRC in the fourth quarter of 2024 and in a total of approximately 40 patients with MSS CRC in the first quarter of 2025...Xilio plans to report safety, pharmacokinetic and pharmacodynamic data from the ongoing Phase 1 clinical trial for XTX301 in the fourth quarter of 2024."

P1/2 data • Colorectal Cancer • Oncology • Solid Tumor

XTX301-01: XTX301 in Patients with Advanced Solid Tumors (clinicaltrials.gov) - P1/2 | N=358 | Recruiting | Sponsor: Xilio Development, Inc. | Phase classification: P1 ➔ P1/2 | N=174 ➔ 358

Enrollment change • Metastases • Phase classification • Breast Cancer • Colorectal Cancer • Endometrial Cancer • Gastrointestinal Cancer • Head and Neck Cancer • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Ovarian Cancer • Prostate Cancer • Solid Tumor • Squamous Cell Carcinoma of Head and Neck • Triple Negative Breast Cancer • MSI

Xilio Therapeutics Announces Pipeline and Business Updates and Second Quarter 2024 Financial Results (GlobeNewswire) - "XTX101: Xilio expects to report initial Phase 2 data for XTX101 in combination with atezolizumab in approximately 20 patients with MSS CRC in the fourth quarter of 2024 and in approximately 20 additional patients (40 patients total) in the first quarter of 2025; XTX301: Xilio expects to report safety, pharmacokinetic and pharmacodynamic data from the ongoing Phase 1 clinical trial for XTX301 in the fourth quarter of 2024."

P1 data • P2 data • Trial status • Colorectal Cancer

Xilio Therapeutics Announces Pipeline and Business Updates and Fourth Quarter and Full Year 2023 Financial Results (GlobeNewswire) - "Xilio today reaffirmed plans to report Phase 1 safety, pharmacokinetic and pharmacodynamic data for XTX301 in patients with advanced solid tumors in the fourth quarter of 2024.....Preclinical data from the company’s first bispecific program, XTX501, a tumor-activated PD-1/IL-2 bispecific development candidate, will be featured at the American Association for Cancer Research (AACR) Annual Meeting 2024 in San Diego, California from April 5-10, 2024."

P1 data • Preclinical • Solid Tumor

Xilio Therapeutics Announces $11.3 Million Private Placement Equity Financing (GlobeNewswire) - "As part of the strategic portfolio reprioritization and workforce reduction, Xilio plans to: focus on rapidly advancing clinical development for XTX301 and XTX101 and leveraging the company’s promising research platform to advance differentiated bispecific and cell engager molecules; discontinue further investment in XTX202 as a monotherapy; and undertake efforts to further reduce its expenses and streamline its operations, including a reduction in headcount of 15 employees, representing approximately 21% of the company’s current workforce."

Pipeline update • Oncology • Solid Tumor

Xilio Therapeutics Announces $11.3 Million Private Placement Equity Financing (GlobeNewswire) - "Xilio Therapeutics, Inc...today announced that it has entered into a securities purchase agreement with certain existing accredited investors, including Bain Capital Life Sciences and Rock Springs Capital, to issue and sell an aggregate of 1,953,125 shares of Xilio common stock at a price of $0.64 per share and prefunded warrants to purchase up to an aggregate of 15,627,441 shares of Xilio common stock at a purchase price of $0.6399 per...'Together with our partnership announced with Gilead today for XTX301, our tumor-activated IL-12, this financing enables us to prioritize clinical development for XTX301 as well as XTX101, our tumor-activated, Fc-enhanced anti-CTLA-4, while making focused investments in our promising research-stage pipeline for tumor-activated bispecific and cell engager molecules.'"

Financing • Oncology • Solid Tumor

Gilead and Xilio Announce Exclusive License Agreement for Tumor-Activated IL-12 Program (Businesswire) - "Gilead Sciences, Inc...and Xilio Therapeutics, Inc...today announced an exclusive license agreement to develop and commercialize Xilio’s Phase 1 tumor-activated IL-12 program, XTX301...Under the terms of the agreement, Xilio granted Gilead an exclusive global license to develop and commercialize XTX301, Xilio’s tumor-activated IL-12. Xilio will receive $43.5 million in upfront payments, including a cash payment of $30 million and an initial equity investment by Gilead of $13.5 million in Xilio common stock at a premium....Xilio will be responsible for conducting clinical development of 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..."

Licensing / partnership • Trial status • Oncology • Solid Tumor

XTX301 in Patients With Advanced Solid Tumors (clinicaltrials.gov) - P1 | N=174 | Recruiting | Sponsor: Xilio Development, Inc. | N=94 ➔ 174

Enrollment change • Metastases • Breast Cancer • Colorectal Cancer • Endometrial Cancer • Gastrointestinal Cancer • Head and Neck Cancer • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Ovarian Cancer • Prostate Cancer • Solid Tumor • Squamous Cell Carcinoma of Head and Neck • Triple Negative Breast Cancer • MSI

Xilio Therapeutics Highlights Recent Advances Across Clinical Pipeline and Encouraging Preliminary Phase 1 Safety Data for XTX301, a Tumor-Activated IL-12, Further Validating the Promise of Its Tumor-Activated Immuno-Oncology Therapies (GlobeNewswire) - P1 | N=94 | NCT05684965 | Sponsor: Xilio Development, Inc. | "Xilio today announced encouraging preliminary safety data from its ongoing Phase 1 trial evaluating XTX301 as a monotherapy in dose escalation in patients with advanced solid tumors; As of a data cutoff date of January 5, 2024, nine patients had been treated with XTX301 in the outpatient setting in Phase 1 dose escalation at three dose levels ranging from 5 ug/kg to 45 ug/kg administered once every three weeks; XTX301 was generally well-tolerated across all dose levels with no dose-limiting toxicities observed in patients as of the data cutoff date....Subject to obtaining sufficient additional capital, Xilio today reaffirmed plans to report Phase 1 safety, pharmacokinetic and pharmacodynamic data for XTX301 in patients with advanced solid tumors in the second half of 2024."

P1 data • PK/PD data • Oncology • Solid Tumor

XTX301 in Patients With Advanced Solid Tumors (clinicaltrials.gov) - P1 | N=94 | Recruiting | Sponsor: Xilio Development, Inc.

Metastases • Trial completion date • Trial primary completion date • Breast Cancer • Colorectal Cancer • Endometrial Cancer • Gastrointestinal Cancer • Head and Neck Cancer • Lung Cancer • Melanoma • Non Small Cell Lung Cancer • Oncology • Ovarian Cancer • Prostate Cancer • Solid Tumor • Squamous Cell Carcinoma of Head and Neck • Triple Negative Breast Cancer • MSI

XTX301, a tumor-activated Interleukin-12 has the potential to widen the therapeutic index of IL-12 treatment for solid tumors as evidenced by pre-clinical studies. (PubMed, Mol Cancer Ther) - "XTX301 was tolerated following four repeat doses up to 2.0 mg/kg in a non-human primate study; XTX301 exposures were substantially higher than those at the minimally efficacious dose in mice. Thus, XTX301 has the potential to achieve potent anti-tumor activity while widening the therapeutic index of IL-12 treatment and is currently being evaluated in a Phase 1 clinical trial."

Journal • Preclinical • Oncology • Solid Tumor • IFNG • IL12A

Xilio Announces Initial Monotherapy Safety and Anti-Tumor Activity Data for XTX202, a Tumor-Activated, Engineered, Beta-Gamma IL-2, in Late Line Patients with Advanced Solid Tumors (GlobeNewswire) - "In addition, subject to obtaining sufficient additional capital, Xilio today announced plans to:...(i) Report initial Phase 2 data for XTX101 in combination with atezolizumab in approximately 20 patients with MSS CRC in the fourth quarter of 2024 and in approximately 20 additional patients (40 patients total) in the first quarter of 2025; (ii) Report Phase 2 monotherapy data for XTX202 in approximately 20 patients treated at the 4.0 mg/kg dose with metastatic RCC or unresectable or metastatic melanoma in the second quarter of 2024; (iii) Report Phase 1 safety and PK/PD data for XTX301 in advanced solid tumors in the second half of 2024."

P1 data • P2 data • Colorectal Cancer • Renal Cell Carcinoma

XTX301, a tumor activated, half-life extended IL-12 promoted potent anti-tumor immunity and activity across multiple syngeneic tumor models (SITC 2023) - P1 | "Conclusions In preclinical models, mXTX301, a tumor activated, half-life extended IL-12, demonstrated remodeling of the TME, anti-tumor activity, and improved tolerability compared to a systemically active IL-12, indicating that XTX301 has potential for activity in both hot and cold tumors while also improving the therapeutic index of IL-12 treatment. XTX301 is being evaluated in a Phase I clinical trial (NCT05684965)."

Preclinical • Oncology • IFNG • IL12A

Xilio Announces Initial Monotherapy Safety and Anti-Tumor Activity Data for XTX202, a Tumor-Activated, Engineered, Beta-Gamma IL-2, in Late Line Patients with Advanced Solid Tumors (GlobeNewswire) - "Xilio anticipates achieving the following milestones in 2023: (i) Activate clinical trial sites for the Phase 1 dose escalation portion of the clinical trial evaluating XTX101...in combination with atezolizumab in the fourth quarter of 2023; (ii) Report preliminary Phase 1 safety data for XTX301...into the third dose level in the fourth quarter of 2023; In addition, subject to obtaining sufficient additional capital, Xilio today announced plans to: (i) Complete Phase 1 combination dose escalation and select a recommended Phase 2 dose for XTX101 in combination with atezolizumab in the second quarter of 2024; (ii) Subject to the results of Phase 1 combination dose escalation, initiate a Phase 2 trial for XTX101 in combination with atezolizumab in patients with MSS CRC in the third quarter of 2024."

P1 data • Trial status • Colorectal Cancer

Xilio Therapeutics Announces Upcoming Presentations at the Society for Immunotherapy of Cancer’s (SITC) 38th Annual Meeting (GlobeNewswire) - "Xilio Therapeutics...announced upcoming poster presentations at the Society for Immunotherapy of Cancer (SITC) 38th Annual Meeting, taking place in San Diego, California from November 1-5, 2023. The company plans to present preliminary anti-tumor activity, safety, pharmacokinetic and pharmacodynamic data from its Phase 1/2 clinical trial for XTX202, a tumor-activated, engineered, beta-gamma biased IL-2, as well as preclinical data for XTX301, a tumor-activated, engineered IL-12."

P1/2 data • Preclinical • Solid Tumor