A Phase 1/2 interventional study of PF-08634404 and Ipilimumab in Carcinoma, Hepatocellular, Hepatocellular Cancer and Hepatocellular Carcinoma, sponsored by Pfizer. Recruiting at 58 sites in 5 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2026-09-28.
Sponsored by Pfizer · Phase 1/2, Interventional, and Treatment
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:
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.
Inclusion Criteria:
Key Exclusion Criteria:
Participants will be allocated to sequential dose levels of PF-08634404 and ipilimumab.
Biological: PF-08634404 · Biological: Ipilimumab
Participants will be randomized to receive either PF-08634404 monotherapy or PF-08634404 combined with ipilimumab.
Biological: PF-08634404 · Biological: Ipilimumab
Solution for infusion
Solution for infusion
Also known as: YERVOY
Number of Participants With Adverse Events
Adverse Events as characterized by type, frequency, severity (as graded by NCI CTCAE version 5.0), timing, seriousness, and relationship to study intervention.
Time frame: Through end of study and up to approximately 24 months
Phase 1b: Number of participants with Dose limiting toxicities (DLT)
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.
Time frame: Through 90 days after the last dose of study intervention; Approximately 24 months
Phase 2: Confirmed Overall Response Rate (ORR) using RECIST 1.1 as assessed by investigator
ORR is the proportion of participants with a best overall response (BOR) of confirmed CR or confirmed PR per RECIST 1.1 by investigator.
Time frame: Approximately 24 months
Phase 2: Recommended dose of PF-08634404 in combination with ipilimumab
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.
Time frame: Approximately 24 months
Phase 1b: Confirmed Objective Response Rate (ORR) using RECIST 1.1 as assessed by investigator
ORR is the proportion of participants with a best overall response of confirmed Complete Response (CR) or confirmed Partial Response (PR) per RECIST 1.1 by investigator.
Time frame: Approximately 24 months
Duration of Response (DOR) per RECIST 1.1 by investigator
DOR is the time from the first documentation of objective response (CR or PR that is subsequently confirmed) to the date of first documented disease progression per RECIST 1.1 as assessed by investigator, or death due to any cause, whichever occurs first.
Time frame: Approximately 24 months
Progression Free Survival (PFS) per RECIST 1.1 by investigator
PFS is defined as the time from the date of first dose to the date of first documented disease progression per RECIST 1.1 as assessed by investigator, or death due to any cause, whichever occurs first.
Time frame: Approximately 24 months
Overall Survival (OS)
OS is defined as the time from the date of first dose to the date of death due to any cause.
Time frame: Approximately 24 months
Number of Participants With Clinical Laboratory Abnormalities
Laboratory abnormalities as characterized by type, frequency, severity (as graded by NCI CTCAE version 5.0), and timing
Time frame: Time from the date of first dose of study intervention through 30-37 days after last dose of study intervention (assessed up to approximately 24 months)
Pharmacokinetics (PK): Serum concentrations of PF-08634404
Predose and/or postdose concentrations of PF-08634404 in combination with ipilimumab.
Time frame: Up to 24 months
Incidence of antidrug antibody against PF-08634404
To evaluate immunogenicity of PF-08634404 in combination with ipilimumab.
Time frame: Up to 24 months
Plan to share: No — Pfizer will provide access to individual de-identified participant data and related study documents (e.g. protocol, Statistical Analysis Plan (SAP), Clinical Study Report (CSR)) upon request from qualified researchers, and subject to certain criteria, conditions, and exceptions. Further details on Pfizer's data sharing criteria and process for requesting access can be found at: https://www.pfizer.com/science/clinical\_trials/trial\_data\_and\_results/data\_requests.
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