Exploring Auger-Enhanced PSMA-Targeted Radioligand Therapy: A First-in-Taiwan Clinical Study of 161Tb-PSMA-I&T

About This Trial

This early-stage study is testing a new type of targeted radiation treatment designed to seek out and destroy prostate cancer cells throughout the body.
It is open to men with advanced prostate cancer that has spread and gotten worse despite standard treatments like chemotherapy and hormone therapy.
To qualify, patients must have a special scan showing that their cancer has the specific protein this treatment targets.
Because this is a first-stage safety study aimed at finding the right dose, participants should expect frequent clinic visits, blood tests, and scans.
Before taking part, you must have adequate kidney, liver, and blood health, and you must not have received other cancer treatments in the weeks leading up to the trial.

More Information

This study is a phase I dose escalation clinical trial aims to evaluate 161Tb-PSMA-I&T, a new generation prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) using Terbium-161 to replace Lutetium-177, its safety, dosimetry, biodistribution, pharmacokinetics, and preliminary efficacy in Taiwanese men with metastatic castration-resistant prostate cancer, and to inform future clinical trials.

Who Can Enroll

Age Range: 20 years and older
Gender: Male
Who This Trial is For: This early-stage study is testing a new type of targeted radiation treatment designed to seek out and destroy prostate cancer cells throughout the body.

Study Details

Start Date: January 1, 2026
Lead Sponsor: National Taiwan University Hospital

Full Eligibility Criteria

Inclusion Criteria

Age ≥ 20 years, ability to understand and willingness to sign informed consent, cooperate with all study-related procedures and assessments including blood tests and imaging
Histologically confirmed adenocarcinoma of the prostate with evidence of metastatic castration-resistant prostate cancer (mCRPC)
Prior surgical orchiectomy or chemical castration maintained on luteinizing hormone-releasing hormone analog, with a serum testosterone level <50 ng/dL (castrate range)
Prior treated with at least one line of taxane-based chemotherapy unless medically unsuitable, and at least one line of androgen receptor pathway inhibitor (e.g., abiraterone, enzalutamide, apalutamide, or darolutamide)
Prior treated with 177Lu-labeled PSMA RLT unless medically unsuitable or declined by the patient
Progressive disease defined according to Prostate Cancer Clinical Trials Working Group 3: Either a PSA progression of more than 2 rising PSA values from baseline with intervals ≥ 1 week, or a soft-tissue progression on images per RECIST 1.1 criteria, or a bone progression on images with more than 2 new lesions
Evidence of significant PSMA-avid lesions on 68Ga- or 18F-labeled PSMA PET/CT within 12 weeks prior to screening, which defined as 68Ga-PSMA or 18F-PSMA uptake greater than that of liver or spleen parenchyma (depend on the tracer used) in at least one metastatic lesion of any size in any organ system
A life expectancy of ≥ 6 months and Eastern Cooperative Oncology Group (ECOG) performance status of 0-2
Adequate bone marrow and organ functions 9.1 Hemoglobin ≥ 10 g/dL without RBC transfusion within 4 weeks 9.2 Absolute neutrophil count ≥ 1.5 × 109/L 9.3 Platelet count ≥ 150 × 109/L 9.4 Creatinine clearance ≥ 50 mL/min (Cockcroft-Gault) 9.5 AST and ALT ≤ 3 × ULN, total bilirubin ≤ 1.5 × ULN
Willingness to comply with the use of medically acceptable forms of barrier contraception if sexually active

Exclusion Criteria

History of allergic reaction to PSMA-targeted compounds or radiometals
Prior radioligand therapy with 223Ra or 177Lu-PSMA within 6 months
Prior surgery or radiotherapy within 4 weeks prior to first investigational dose
Prior systemic therapies against prostate cancer within 4 weeks, including androgen receptor pathway inhibitor, chemotherapy, targeted therapy such as PARP inhibitors (PARPi)
Discordant disease on PET images: FDG-positive disease with minimal PSMA expression
Urinary tract obstruction causing hydronephrosis unless appropriately treated beforehand
Known symptomatic brain metastases or leptomeningeal disease, symptomatic or impending cord compression unless appropriately treated beforehand
Other active malignancy requiring systemic treatment
Significant cardiovascular disease (e.g., recent myocardial infarction, unstable angina)
Concurrent severe uncontrolled illness that may jeopardize patient safety, including uncontrolled infections