Alpha-emitting therapy for advanced prostate cancer

Phase I Dose Escalation Study to Evaluate Tolerability and Safety of 225Ac-PSMA I&T in Patients With Metastatic Prostate Cancer

Phase 1 Interventional Erasmus Medical Center · NCT05902247

This study is testing a new type of radiation treatment for advanced prostate cancer to see if it's safe and how well it works for patients.

Quick facts

PhasePhase 1
Study typeInterventional
Enrollment30 (estimated)
Ages18 Years and up
SexMale
SponsorErasmus Medical Center Academic / other
Drugs / interventionschemotherapy, Radiation
Locations1 site (Rotterdam, Zuid-Holland)
Trial IDNCT05902247 on ClinicalTrials.gov

What this trial studies

This clinical trial evaluates the safety and tolerability of a new radiopharmaceutical, 225Ac-PSMA I&T, for treating metastatic castration-resistant prostate cancer. The study involves a single-center, single-arm, phase I dose escalation design, where up to 30 patients will receive therapy with varying doses of the radionuclide. Patients will undergo PET-MRI scans to assess the effects of the treatment on cancer metastases and to determine the appropriate dosage for future studies.

Who should consider this trial

Good fit: Ideal candidates for this study are men with histologically confirmed metastatic castration-resistant prostate cancer who have shown disease progression after prior treatments.

Not a fit: Patients who are not experiencing progression of their prostate cancer or those currently receiving active anti-tumor therapies may not benefit from this study.

Why it matters

Potential benefit: If successful, this therapy could provide a new treatment option for patients with advanced prostate cancer that is resistant to standard therapies.

How similar studies have performed: Other studies using radiopharmaceuticals for prostate cancer have shown promising results, indicating potential for success with this novel approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histopathological proven metastatic castration resistant prostate cancer. Castrationresistant disease is defined as a serum testosterone level of 50 nanogram per deciliter or lower (≤1.7 nanomol per liter) after bilateral orchiectomy or during maintenance treatment consisting of androgen-ablation therapy with a luteinizing hormone-releasing hormone agonist.
* Evidence of progressive disease, defined as 1 or more Prostate Cancer Work Grouping 3 (PCWG3) criteria: - PSA level ≥ 1 ng/mL that has increased on at least 2 successive occasions at least 1 week apart
* Progression as defined by RECIST 1.1 with PCGW3 modifications
* Progression after at least one line of chemotherapy and/or one line of nonsteroidal antiandrogen (NSAA).
* No active anti-tumor therapy, except for androgen deprivation therapy in combination with at least one androgen receptor-targeted agent
* Willing and able to undergo 2 cycles of 225Ac-PSMA I\&T therapy and 3 PET-MRI scans in 16 weeks and comply with protocol
* Signed and dated written informed consent by the patient (or legal representative) prior to any study-specific procedures.
* Age ≥ 18 years.
* Eastern Cooperative Oncology Group (ECOG) performance-status score 0-2.
* Use of highly effective methods of contraception (female partners of male participants)
* During the trial and 6 months after completion of the study or willing to practice sexual abstinence.

Exclusion Criteria:

* Concurrent severe illness or clinically relevant trauma within 2 weeks before the administration of the investigational product that might preclude study completion or interfere with study results
* Serum hemoglobin ≤ 6.2 mmol/L, total white blood cell (WBC) count ≤ 3.5·109/L, absolute neutrophil count ≤ 1.5·109/L, platelet count ≤ 100·109/L, serum creatinine concentration ≥ 150 umol/L (≥ 1.7 mg/dL), serum albumin \<30 g/L, bilirubin ≥ 1.5 x upper limit normal (ULN), aspartate transaminase (ASAT) ≥ 3 x ULN and alanine aminotransferase (ALAT) ≥ 3 x ULN (or bilirubin ≥ 3 x ULN, ASAT ≥ 5 x ULN and ALAT ≥ 5 x ULN in the case of pre-existing liver metastases at baseline)
* Concurrent bladder outflow obstruction or unmanageable urinary incontinence
* Known or expected hypersensitivity to Gallium-68, Actinium-225, PSMA I\&T, or any excipient present in 225Ac/68Ga-PSMA I\&T
* Prior administration of a radiopharmaceutical within a period corresponding to 8 halflives of the radionuclide used on such radiopharmaceutical
* Prior treatment with any radionuclide therapy
* History of somatic or psychiatric disease/condition that may interfere with the objectives and assessments of the study
* Central nervous system (CNS) metastases, leptomeningeal disease, or spinal cord compression
* Radiation therapy within 4 weeks of first dose (or local or focal radiotherapy within 2 weeks of first dose)
* Male subjects unwilling to abstain from donating sperm during treatment and for an additional 6 months after the last dose

Where this trial is running

Rotterdam, Zuid-Holland

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Prostatic Neoplasms, Castration-Resistant225Ac-PSMAProstate cancer
Last reviewed 2026-06-09 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.