NCT07227012 · Pfizer
Symbiotic-GI-13: A Study to Learn About Study Medicine Called PF-08634404 as a Single Treatment and Combination Treatment in Adult Participants With a Liver Cancer Called Hepatocellular Carcinoma, That is Too Advanced to be Removed by Surgery and May Have Spread to Other Parts of the Body.
What this study is about
The purpose of this study is to learn about the effects of study medicine (PF-08634404) when given alone or with another antibody (ipilimumab) for the treatment of a type of liver cancer called hepatocellular carcinoma (HCC) that is either locally advanced (spread to nearby tissues) or has spread to other parts of the body.
View original scientific description
The purpose of this study is to learn about the effects of study medicine (PF-08634404) when given alone or with another antibody (ipilimumab) for the treatment of a type of liver cancer called hepatocellular carcinoma (HCC) that is either locally advanced (spread to nearby tissues) or has spread to other parts of the body. To join the study, participants must meet the following conditions: * Be 18 years or older. * Have locally advanced or metastatic HCC. * Is not a candidate for complete surgical or loco-regional therapies. * Have not received any whole-body treatment for HCC. Participants will receive PF-08634404 either alone or in combination with ipilimumab. The medicine will be given through intravenous (IV) infusions, which means it will be administered directly into a vein. All treatments will take place at clinical trial sites, where trained medical staff will monitor participants during and after each visit.
Interventions
BIOLOGICAL
PF-08634404
Solution for infusion
BIOLOGICAL
Ipilimumab
Solution for infusion
Primary outcome measures
Number of Participants With Adverse Events
Time frame: Through end of study and up to approximately 24 months
Adverse Events as characterized by type, frequency, severity (as graded by NCI CTCAE version 5.0), timing, seriousness, and relationship to study intervention.
Phase 1b: Number of participants with Dose limiting toxicities (DLT)
Time frame: Through 90 days after the last dose of study intervention; Approximately 24 months
DLTs are a predefined set of adverse events that are at least possibly related to any or all of the study interventions. The number of participants who experienced DLTs during the DLT observation period.
Phase 2: Confirmed Overall Response Rate (ORR) using RECIST 1.1 as assessed by investigator
Time frame: Approximately 24 months
ORR is the proportion of participants with a best overall response (BOR) of confirmed CR or confirmed PR per RECIST 1.1 by investigator.
Phase 2: Recommended dose of PF-08634404 in combination with ipilimumab
Time frame: Approximately 24 months
The doses of PF-08634404 and ipilimumab selected to be used in combination based on safety, tolerability, pharmacokinetics, and initial anti-tumor efficacy from Phase 2.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- 18 years of age or older at screening.
- Locally advanced or metastatic HCC with diagnosis confirmed by histology/cytology or clinically by AASLD criteria (for patients with cirrhosis). Participants without cirrhosis require histological confirmation of diagnosis.
- Disease that is not amenable to curative surgical and/or locoregional therapies, or progressive disease after surgical and/or locoregional therapies.
- At least 1 measurable (as defined by RECIST 1.1 per investigator) and untreated lesion.
- Adequate hepatic, liver, and renal function
- No prior systemic therapy for HCC.
- ECOG performance status 0 or 1
- Child-Pugh Class A Key
Exclusion criteria
- Moderate or severe ascites.
- History of hepatic encephalopathy.
- Participants with known active CNS lesions, including leptomeningeal metastasis, brainstem, meningeal, or spinal cord metastases or compression.
- Clinically significant risk of hemorrhage or fistula.
- Participants with any history of another malignancy within 3 years.
- History of allogeneic organ transplantation and allogeneic hematopoietic stem cell transplantation.
- Participants with active autoimmune diseases requiring systemic treatment within the past 2 years.
- Clinically significant cardiovascular disease within 6 months prior to the first dose.
- Major surgery or severe trauma within 4 weeks prior to the first dose or planned major surgery during the study.
- History of severe bleeding tendency or coagulation dysfunction.
- History of severe ulcers, unhealed wounds, gastrointestinal perforation, abdominal fistula, gastrointestinal obstruction, intra-abdominal abscess, or acute gastrointestinal bleeding, including bleeding event due to esophageal and/or gastric varices, within 6 months prior to the first dose.
- Participants with acute, chronic or symptomatic infections.
- Participants with history of immunodeficiency.
Where
- Irvine, California
- Los Angeles, California
- Orange, California
- Pasadena, California
- Land O' Lakes, Florida
- Ruskin, Florida
- Tampa, Florida
- Wesley Chapel, Florida
- Shiloh, Illinois
- Coon Rapids, Minnesota
- Minneapolis, Minnesota
- Saint Paul, Minnesota
And 10 more locations — see the full list below.
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Aug 17, 2026 · Source of record for eligibility and locations