4-IODOPHENYLALANINE I-131

Clinical trials are studying 4-IODOPHENYLALANINE I-131 in people with recurrent glioblastoma. These trials look at safety, tolerability, dose selection, and whether treatment may improve survival compared with standard care alone.

Table of Contents

Trial overview

The available trial data describe one interventional study of 4-IODOPHENYLALANINE I-131 in people with recurrent glioblastoma.[1] The study is authorised and planned for 50 participants.[1]

The full trial title shows that the study compares TLX101-Tx plus standard of care versus standard of care alone for patients with recurrent glioblastoma.[1] The brief summary also says the study is looking at whether the treatment can improve overall survival compared with lomustine alone.[1]

Who can join

The target population is patients with confirmed first recurrence of glioblastoma.[1] In simple terms, this means the cancer has returned for the first time after earlier treatment.

The trial data do not list broader eligibility details such as age limits, lab values, or previous treatments.[1] Based on the source, the key entry point is having recurrent glioblastoma at the first return of the disease.[1]

What is being tested

The study uses 4-IODOPHENYLALANINE I-131 as part of TLX101-Tx, and it is tested with lomustine in one part of the trial.[1] Lomustine is the standard treatment named in the trial data for the comparison group and combination group.[1]

The brief summary also notes that TLX101-Tx may be studied as a monotherapy, which means used alone, depending on the totality of data from Part 1.[1] This tells us the study is not only about one fixed treatment plan, but also about selecting the best approach from the early results.[1]

Study design and phases

This is a Phase 3 study, which is a late-stage clinical trial designed to compare treatments in a larger group of patients.[1] The trial has two main parts: a safety and dosimetry lead-in, and a randomized study.[1]

In Part 1a, the study aims to optimize the dose and determine the recommended Phase 3 dose, as well as the maximum tolerated dose.[1] In Part 1b, the study expands enrollment to check safety, tolerability, and the recommended Phase 3 study dose in patients with confirmed first recurrence of glioblastoma.[1]

The randomized Part 2 compares TLX101-Tx with lomustine against lomustine alone to see whether the treatment improves survival.[1] Randomized means patients are assigned to groups by chance, which helps make the comparison fairer.[1]

What the trial measures

The main outcomes include dose-limiting adverse events, which are side effects serious enough to affect dose selection, and other safety findings such as physical examination results, vital signs, ECG abnormalities, laboratory tests, and adverse events graded by NCI CTCAE v5.0.[1]

The study also measures tolerability using quality-of-life questionnaires, including EORTC QLQ-C30 and EORTC-BN20, and neurological symptoms using the NANO scale.[1] These tools help show how treatment affects daily life and brain-related symptoms, not just tumor control.[1]

For the randomized part of the trial, the key endpoint is overall survival, measured from the date of enrollment until death from any cause.[1] This is a direct way to see whether the new treatment helps patients live longer.[1]

What this means for patients

For patients, this trial is mainly about whether a new treatment plan that includes 4-IODOPHENYLALANINE I-131 can be used safely and whether it may help people with recurrent glioblastoma live longer.[1] The early part of the study is used to find the right dose and check for major safety problems before the larger comparison.[1]

The trial also looks at quality of life and neurological symptoms, which is important in a brain tumor study because treatment effects are not only about survival.[1] In short, the study is testing both medical benefit and how patients feel during treatment.[1]

Trial ID Phase Condition studied Status Enrollment
2025-521785-10-00 Phase 3 Glioblastoma Authorised 50

Ongoing Clinical Trials on 4-IODOPHENYLALANINE I-131

  • Study of iodofalan (131I) and lomustine combination therapy compared to lomustine alone in patients with first recurrent glioblastoma

    Recruiting

    3 1 1 1
    Investigated diseases:
    Austria Belgium Denmark The Netherlands

Glossary

  • Glioblastoma: A fast-growing type of brain tumor. In this trial, the focus is on cases that have come back after treatment.
  • Recurrent: A disease that has returned after it seemed to improve or disappear.
  • Phase 3: A late-stage clinical trial that compares treatments to see how well they work and how safe they are.
  • Interventional study: A study where researchers give a treatment and watch what happens.
  • Safety: How well a treatment can be used without causing unacceptable problems.
  • Tolerability: How well a patient can handle a treatment.
  • Dosimetry: A way to measure how much radiation is delivered to the body or tumor.
  • Dose-limiting: A side effect or problem that can stop a dose from being increased.
  • Overall survival: The length of time from joining the study until death from any cause.
  • Quality of life: How a patient feels and functions in daily life during treatment.
  • Neurological symptoms: Problems related to the brain, nerves, or spinal cord, such as changes in movement, speech, or thinking.

References

  1. https://clinicaltrials.gov/study/2025-521785-10-00