Individualized Dosimetry for Holmium-166-radioembolization in Patients With Unresectable Hepatocellular Carcinoma — iHEPAR  

Hepatocellular Carcinoma Non-resectable Clinical Trial

Official title: Individualized Dosimetry for Holmium-166-radioembolization in Patients With Unresectable Hepatocellular Carcinoma; a Multi-center, Interventional, Non-randomized, Non-comparative, Open Label, Early Phase II Study

Status Recruiting

Clinical Trial Summary

Patients with hepatocellular carcinoma often die from intrahepatic disease because current treatment options are limited. Local treatment using 166Ho-radioembolization (166Ho-RE) offers a safe and effective treatment. Because 166Ho-microspheres are used as a scout dose for treatment simulaton and for the actual treatment itself, a tailored approach can be used. This concept has proven to be more predictive than the 90Y-radioembolization concept (current standard-of-care), which is a based on a surrogate scout dose (i.e. 99mTc-MAA). A personal treatment plan may be used for 166Ho-radioembolization to optimize efficacy, based on scout dose distribution. However, individualized treatment planning inherently leads to treatment doses that deviate from the currently approved 'one-size-fits-all' approach (i.e. 60 Gy average absorbed dose for all patients). Therefore, safety of individualized 166Ho-RE will be evaluated first to validate safety and confirm safety thresholds. These thresholds will be used in subsequent randomized controlled studies.

Clinical Trial Description

The presented study proposal is a sequel study after a successful completion of the HEPAR Primary study (all patients were treated, last follow-up visit planned for August 2020). In the HEPAR Primary study, all treatments were planned using one compartment modeling, which included the target volume without distinction between tumor and non-tumor compartments. Each patient was treated with an average absorbed dose of 60 Gy in the target volume. In some patients this treatment approach resulted in a high tumor and low normal liver absorbed dose, in others this resulted in the opposite. No distinction was made because thresholds for a safe normal liver and effective tumor absorbed dose were not known, since HEPAR Primary was the first clinical study on 166Ho-RE in HCC. The study confirmed safety of a 60 Gy average absorbed dose and gave insights in the previously unknown thresholds for a safe normal liver and effective tumor absorbed dose. The primary hypothesis of the iHEPAR study is that dosimetry-based individualized treatment planning is at least as safe as standard of care one compartment treatment planning, used in HEPAR Primary, but with the potential of improved treatment outcomes. One compartment modeling has the inherent risk of under- or over-dosing. Dosimetry-based individualized treatment planning aims for an effective tumor absorbed dose, while keeping the non-tumor absorbed dose within safety limits. So far, only one compartment modeling was established as a safe and effective treatment approach in 166Ho-RE. This phase II study aims to evaluate the safety and efficacy of dosimetry-based individualized 166Ho-RE in HCC. This data will be used for the design of future randomized controlled trials. ;

Related Conditions & MeSH terms

• Carcinoma
• Carcinoma, Hepatocellular
• Hepatocellular Carcinoma Non-resectable

• NCT number: NCT05114148
• Study type: Interventional
• Source: UMC Utrecht
• Status: Recruiting
• Phase: N/A
• Start date: March 1, 2022
• Completion date: November 1, 2025