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I131
Iodine-131 is a radioactive isotope that emits beta particles to destroy thyroid cancer cells and other iodine-avid malignancies.
Iodine-131 is a radioactive isotope that emits beta particles to destroy thyroid cancer cells and other iodine-avid malignancies. Used for Differentiated thyroid cancer (papillary and follicular) with radioactive iodine-avid metastases, Thyroid cancer recurrence and metastatic disease.
At a glance
| Generic name | I131 |
|---|---|
| Also known as | low dose RAI |
| Sponsor | Gustave Roussy, Cancer Campus, Grand Paris |
| Drug class | Radiopharmaceutical |
| Target | Sodium-iodide symporter (NIS) |
| Modality | Small molecule |
| Therapeutic area | Oncology |
| Phase | Phase 3 |
Mechanism of action
I-131 is taken up selectively by thyroid follicular cells and other tissues expressing the sodium-iodide symporter, delivering targeted radiation that destroys cancer cells while sparing surrounding tissue. The beta particles emitted have a short range (typically a few millimeters), allowing localized cell killing. This approach is particularly effective for differentiated thyroid cancers and metastases that retain iodine-uptake capacity.
Approved indications
- Differentiated thyroid cancer (papillary and follicular) with radioactive iodine-avid metastases
- Thyroid cancer recurrence and metastatic disease
Common side effects
- Salivary gland dysfunction
- Bone marrow suppression
- Secondary malignancy risk
- Hypothyroidism
Key clinical trials
- Trametinib in Increasing Tumoral Iodine Incorporation in Patients With Recurrent or Metastatic Thyroid Cancer (PHASE2)
- Study of Iopofosine I-131 (CLR 131) in Select B-Cell Malignancies (CLOVER-1) With Expansion in Waldenstrom (PHASE2)
- Novel Targeted Radiotherapy in Pediatric Patients With Inoperable Relapsed or Refractory HGG (PHASE1)
- Dose Escalation Study of CLR 131 in Pediatric Relapsed/Refractory Malignant Tumors Including Neuroblastoma and Sarcomas (PHASE1)
- S0016 Combination Chemotherapy With Monoclonal Antibody Therapy in Newly Diagnosed Non-Hodgkin's Lymphoma (PHASE3)
- Iodine I 131 Metaiodobenzylguanidine in Treating Patients With Recurrent, Progressive, or Refractory Neuroblastoma or Malignant Pheochromocytoma or Paraganglioma (PHASE2)
- Testing the Addition of 131I-MIBG or Lorlatinib to Intensive Therapy in People With High-Risk Neuroblastoma (NBL) (PHASE3)
- The Use of 124-I-PET/CT Whole Body and Lesional Dosimetry in Differentiated Thyroid Cancer (PHASE2)
Primary sources
Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.
| Source | Used for |
|---|---|
| ClinicalTrials.gov | Trial enrolment, design, endpoints, results |
Competitive intelligence
For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:
- I131 CI brief — competitive landscape report
- I131 updates RSS · CI watch RSS
- Gustave Roussy, Cancer Campus, Grand Paris portfolio CI