T-Cell Therapy (ECT204) in Adults With Advanced HCC

Inclusion Criteria:

• Histologically confirmed HCC, that is unresectable, recurrent, and/or metastatic.

• GPC3-positive tumor expression confirmed by immunohistochemistry (IHC).

• For the dose-escalation cohort: ≥10-20% tumor cells, ≥2+ IHC.

• Beginning with the RP2D confirmatory cohort: ≥ 50% tumor cells, 2+/3+ IHC.

• Must have failed, or not tolerated, at least two (2) different anti-HCC systemicagents.

• Life expectancy of at least 4 months per the Investigator's opinion.

• Karnofsky Performance Scale of 70 or higher.

• Measurable disease by RECIST v1.1.

• Child-Pugh score of A6 or better.

• Adequate organ function.

Exclusion Criteria:

• Pre-existing illness (e.g., symptomatic congestive heart failure) that would limitcompliance with study requirements.

• Active, uncontrolled systemic bacterial, fungal, or viral infection. Subjects withHuman Immunodeficiency Virus (HIV), hepatitis B, or hepatitis C are eligibleprovided their infection is being treated and the viral load is controlled.

• Active malignancy (other than HCC), with the exception of cholangiocarcinoma (CCA)or any malignancy without any organ involvement and with an expected survival ≥ 3years without any treatment (exception: hormone/androgen- deprivation therapy).

• Pregnant or lactating women.

• Currently receiving or ending (< 14 days from date of consent) liver tumor-directedtherapy (e.g., radiation, ablation, embolization), or hepatic surgery.

• Concurrently receiving other investigational agents, biological, chemical, orradiation therapies, while participating in the study.

• Active autoimmune disease requiring systemic immunosuppressive therapy.

• Presence of portal vein tumor thrombus (PVTT) classified as grade Vp4, or anyinvasion into the inferior vena cava (IVC).

• Ascites requiring active treatment.

• History of organ transplant.

• Advanced HCC involving greater than half (50%) of the liver.