Tizona Therapeutics

Tizona Therapeutics is a clinical-stage biopharmaceutical company based in South San Francisco, California, focused on immuno-oncology. According to its official website, the company aims to improve outcomes for people with cancer by translating novel scientific insights into first-in-class immunotherapies, and describes its scientists as enabling transformational shifts in cancer treatment. Its stated mission is to change the course of cancer progression and relapse through novel scientific insights. The company's pipeline is centered on restoring and bolstering immune responses against cancer. Its lead program is TTX-080, described as a first-in-class HLA-G specific antagonist. Tizona states that HLA-G suppresses both adaptive and innate immune activity, and that TTX-080 has the potential to enhance anti-tumor responses. The company is enrolling patients in two randomized arms within an ongoing Phase 1b clinical trial (NCT04485013) evaluating either TTX-080 plus cetuximab and FOLFIRI or cetuximab and FOLFIRI alone in biomarker-defined metastatic colorectal cancer. An October 31, 2024 news item announced expansion of the Phase 1b trial to evaluate TTX-080 in combination with the EGFR inhibitor cetuximab and chemotherapy in advanced colorectal cancer. Tizona presents its clinical and translational data at major oncology conferences. At ASCO 2024 (May 15, 2024) it presented Phase 1b TTX-080 clinical data in advanced colorectal cancer and head and neck squamous cell carcinoma. At SITC 2025 (November 7, 2025) it presented clinical translational evidence of dual innate and adaptive immune activation with TTX-080 in patients with advanced solid tumors. The company also publishes peer-reviewed work, including a February 15, 2026 article in the Journal for ImmunoTherapy of Cancer titled "Unlocking the promise of innate biology through the HLA-G/ILT2/ILT4 pathway." Tizona is led by Chief Executive Officer Christine O'Brien, who joined the company in 2015 and previously served as its Chief Operating Officer; she is also a member of the Board of Directors. The leadership team also includes Chief Scientific Officer Courtney Beers, PhD, and Chief Medical Officer Robert Ilaria, Jr., MD, along with Senior Vice President Erin Johnson, PhD, and Clinical Advisor Swami Murugappan, MD, PhD. The company emphasizes a culture of grit, expertise and passion, and states that it works with external partners and investors, believing that teams transcending corporate walls can transform patient lives. It is a private company; no parent company or public listing is indicated in the available evidence.

Tizona Therapeutics is a clinical-stage immuno-oncology company located in South San Francisco, California. Public information about the company's earliest corporate history is limited in the available evidence; its official website and leadership pages describe an organization built around translating novel scientific insights into first-in-class immunotherapies for cancer. A key marker of the company's development is the tenure of its Chief Executive Officer, Christine O'Brien, who joined Tizona in 2015 and most recently served as Chief Operating Officer before becoming CEO and a member of the Board of Directors. During her time at the company, Tizona advanced two first-in-class immunotherapies into the clinic, and O'Brien led cross-functional execution of the company's portfolio and operating plan as well as clinical-stage project teams working with external partners. Before Tizona, O'Brien held roles at Onyx Pharmaceuticals, an Amgen subsidiary, including Senior Director of Strategic Operations and Chief of Staff to the President, and Product Team Leader for Kyprolis; from 2003 to 2015 she held positions of increasing responsibility at Amgen. The company's scientific focus is the HLA-G pathway. Tizona states that HLA-G suppresses both adaptive and innate immune activity, and it has developed TTX-080 as a first-in-class HLA-G specific antagonist intended to enhance anti-tumor responses. The company has conducted clinical development of TTX-080 in advanced solid tumors, including metastatic colorectal cancer and head and neck squamous cell carcinoma. An ongoing Phase 1b clinical trial (NCT04485013) includes two randomized arms evaluating either TTX-080 plus cetuximab and FOLFIRI or cetuximab and FOLFIRI alone in biomarker-defined metastatic colorectal cancer. On October 31, 2024, Tizona announced expansion of the Phase 1b trial to evaluate TTX-080 in combination with the EGFR inhibitor cetuximab and chemotherapy in advanced colorectal cancer. Tizona has reported its data at major oncology meetings. At ASCO 2024 (May 15, 2024), it presented Phase 1b TTX-080 clinical data in advanced colorectal cancer and head and neck squamous cell carcinoma. At SITC 2025 (November 7, 2025), it presented clinical translational evidence of dual innate and adaptive immune activation with TTX-080 in patients with advanced solid tumors. The company also contributes peer-reviewed publications, including a February 15, 2026 article in the Journal for ImmunoTherapy of Cancer on unlocking the promise of innate biology through the HLA-G/ILT2/ILT4 pathway. Tizona describes itself as driven by grit, expertise and passion, and emphasizes collaboration with external partners, advisors and investors. Its leadership team includes Chief Scientific Officer Courtney Beers, PhD, Chief Medical Officer Robert Ilaria, Jr., MD, Senior Vice President Erin Johnson, PhD, and Clinical Advisor Swami Murugappan, MD, PhD. The company is privately held, and the available evidence does not identify a parent company or a stock exchange listing.

• Christine O'Brien joins Tizona; she later serves as Chief Operating Officer and then Chief Executive Officer.

• Tizona presents Phase 1b TTX-080 clinical data in advanced colorectal cancer and head and neck squamous cell carcinoma at ASCO 2024.

• Tizona announces expansion of the Phase 1b clinical trial to evaluate TTX-080 in combination with cetuximab and chemotherapy in advanced colorectal cancer.

• Tizona presents clinical translational evidence of dual innate and adaptive immune activation with TTX-080 in patients with advanced solid tumors at SITC 2025.

• Tizona authors a Journal for ImmunoTherapy of Cancer article on the HLA-G/ILT2/ILT4 pathway.

Clinical-stage immuno-oncology company developing first-in-class immunotherapies that restore and bolster immune responses against cancer.

• TTX-080

  A first-in-class HLA-G specific antagonist antibody being evaluated in advanced solid tumors, including metastatic colorectal cancer and head and neck squamous cell carcinoma.

1. 1Tizona Therapeutics | Improving outcomes for people with cancertizonatx.com
2. 2Leadership | Board or Directors | Investors | Tizona Therapeuticstizonatx.com
3. 3Pipeline and Science | TTX-080 (Anti-HLA-G Antibody) | Tizona Therapeuticstizonatx.com
4. 4Tizona Therapeutics (United States) - Wikidatawikidata.org