Tracer library / [131I]MIBG
Structure of 3-Iodobenzylguanidine (unlabelled parent compound, from PubChem)
Unlabelled parent compoundPubChem CID 60860

[131I]MIBG

Also written as MIBG; [I-131]MIBG; I-131-MIBG; mIBG; [I-131]mIBG; [I-131]meta-iodobenzylguanidine
Radionuclide
I-131 t½ 11549 min
Modality
Therapy
Production route
—
Stage
Approved
Syntheses indexed
2
Neuroendocrine neoplasmsOther radioligand therapyNeuroblastoma (paediatric)

What it is

Compound class
Radioiodinated benzylguanidine (norepinephrine analog)
Target / mechanism
Norepinephrine transporter PMID 39978816
Clinical application
Targeted radionuclide therapy of neuroendocrine tumors (neuroblastoma, pheochromocytoma/paraganglioma) PMID 9649115
Theranostic pair
[123I]MIBG

Regulatory status

FDA
Yes — 2018; Azedra (iobenguane I-131); sponsor PROGENICS PHARMS INC; NDA 209607. Earlier: iobenguane sulfate I 131 (diagnostic), sponsor PHARMALUCENCE, NDA 020084, 1994. openFDA marketing status of BOTH products: 'Discontinued' Drugs@FDA / openFDA drug registry: NDA 209607 (original approval 2018-07-30) — https://api.fda.gov/drug/drugsfda.json?search=application_number:%22NDA209607%22; NDA 020084 (original approval 1994-03-25) — https://api.fda.gov/drug/drugsfda.json?search=application_number:%22NDA020084%22 (queried 2026-09-18); both list marketing status 'Discontinued'
EMA (centralised)
No EMA medicines register (JSON export 2026-09-18): no iobenguane (131I) entry (the only 131I iodine-labelled entry, Omblastys = iodine (131I) omburtamab, is a different substance and was refused)
Other approvals
—
Brand names
—

Published syntheses

ModuleCassettePurificationYield %RCP %Precursor / supplierSource
—custom manifold———Resin-supported MBG precursor
Progenics Pharmaceuticals, Inc., a Lantheus company
35861867
2022 Clin Cancer Res
Manual synthesis—————9649115
1998 Br J Cancer
Using a no-carrier-added synthesis route, we produced 123I-, 125I-, 131I- and 211At-labelled benzylguanidines

Clinical literature

Clinical studies in the indexed corpus, ordered by design (multicentre, prospective, retrospective, others, case reports last) and then by year. Titles and links only, as published; this is not a summary of the evidence.

  1. Peripheral Stem Cell Apheresis is Feasible Post 131Iodine-Metaiodobenzylguanidine-Therapy in High-Risk Neuroblastoma, but Results in Delayed Platelet Reconstitution.
    2019 · Clin Cancer Res · Prospective, multicentre
  2. Efficacy and Safety of High-Specific-Activity 131I-MIBG Therapy in Patients with Advanced Pheochromocytoma or Paraganglioma.
    2019 · J Nucl Med · Multicentre · Phase II
  3. Efficacy and Safety of 124I-MIBG Dosimetry-Guided High-Activity 131I-MIBG Therapy of Advanced Pheochromocytoma or Neuroblastoma.
    2023 · J Nucl Med · Prospective
  4. Clinical, Diagnostic, and Treatment Characteristics of SDHA-Related Metastatic Pheochromocytoma and Paraganglioma.
    2019 · Front Oncol · Prospective, retrospective
  5. Impact of acquisition timing and background uptake on [ 131 I]meta-iodobenzylguanidine SPECT/CT interpretation in pheochromocytoma and adrenal adenoma.
    2026 · Nucl Med Commun · Retrospective
  6. Clinical Profile, Outcomes, and Predictors of Malignant Pheochromocytoma and Paraganglioma: Insights From a Single-Center Cohort.
    2025 · Clin Endocrinol (Oxf) · Retrospective
  7. Semi-quantitative MIBG scores in relapsed/refractory neuroblastoma: Prognostic insights from post-131I-MIBG treatment scans and impact of SPECT-CT imaging.
    2025 · Rev Esp Med Nucl Imagen Mol (Engl Ed) · Retrospective
  8. Why do patients with pheochromocytomas/paragangliomas exhibit significantly inconsistent elevation of catecholamines and their metabolites? a large Chinese cohort study.
    2025 · Endocrine · Retrospective
  9. [The relationship between clinical characteristics and pathological features in patients with pheochromocytomas/paragangliomas].
    2024 · Zhonghua Yi Xue Za Zhi · Retrospective
  10. Trends in analgesia-sedation of pediatric patients receiving I-131 MIBG in the pediatric intensive care unit: A report from the Pediatric Health Information System database.
    2024 · Pediatr Blood Cancer · Retrospective
Show all 44 clinical studies
  1. Predictive Factors of Early 18F-Fluorodeoxyglucose-Positron Emission Tomography Response to [131I] Metaiodobenzylguanidine Treatment for Unresectable or Metastatic Pheochromocytomas and Paragangliomas.
    2024 · Neuroendocrinology · Retrospective
  2. Development and internal validation of a novel predictive model for SDHB mutations in pheochromocytomas and retroperitoneal paragangliomas.
    2023 · Front Endocrinol (Lausanne) · Retrospective
  3. Prognostic value of [18F]FDG-PET prior to [131I]MIBG treatment for pheochromocytoma and paraganglioma (PPGL).
    2023 · Ann Nucl Med · Retrospective
  4. A 10-year observational single-center study of retroperitoneal unicentric Castleman disease.
    2021 · Medicine (Baltimore) · Retrospective
  5. The utility of 68Ga-DOTATATE PET/CT in localizing primary/metastatic pheochromocytoma and paraganglioma in children and adolescents - a single-center experience.
    2021 · J Pediatr Endocrinol Metab · Retrospective
  6. Predictors of Survival in 211 Patients with Stage IV Pulmonary and Gastroenteropancreatic MIBG-Positive Neuroendocrine Tumors Treated with 131I-MIBG.
    2018 · J Nucl Med · Retrospective
  7. Semiquantitative 131 I MIBG Scintigraphy Predicts Intraoperative Blood Pressure Fluctuation in Patients Undergoing Surgery for Pheochromocytoma and Paraganglioma.
    2025 · Clin Nucl Med · Clinical study
  8. Ex vivo-expanded and activated haploidentical natural killer cells infusion before autologous stem cell transplantation in high-risk neuroblastoma: a phase I/II pilot study.
    2025 · Cancer Immunol Immunother · Clinical study · Phase I/II
  9. Case Series: ATRX Variants in Four Patients with Metastatic Pheochromocytoma.
    2024 · Front Endocrinol (Lausanne) · Clinical study
  10. Long-term disease-free survival after MIBG therapy for metastatic pheochromocytoma.
    2024 · BMJ Case Rep · Clinical study
  11. Unusual Renal Uptake of 131 I-MIBG in a Young Hypertensive With Renal Artery Stenosis.
    2024 · Clin Nucl Med · Clinical study
  12. Rare and aggressive metastatic pheochromocytoma recurrence in a patient with MEN 2A syndrome.
    2024 · BMJ Case Rep · Clinical study
  13. Norepinephrine transporter and vesicular monoamine transporter 2 tumor expression as a predictor of response to 131 I-MIBG in patients with relapsed/refractory neuroblastoma.
    2024 · Pediatr Blood Cancer · Clinical study
  14. Diagnosis, Genetics, and Management of 24 Patients With Cardiac Paragangliomas: Experience From a Single Center.
    2023 · J Endocr Soc · Clinical study
  15. [A Report on Health Resource Use of Internal Radiation Therapy with 131I-MIBG (2nd Survey)].
    2023 · Kaku Igaku · Clinical study
  16. Nurses' Experiences Caring for Children With Neuroblastoma Receiving 131I-Metaiodobenzylguanidine Therapy: A Qualitative Descriptive Study.
    2023 · J Pediatr Hematol Oncol Nurs · Clinical study
  17. The Experience of Children With Neuroblastoma and Their Parents During Single-Room Isolation for 131I-Metaiodobenzylguanidine Therapy: A Qualitative Descriptive Study.
    2022 · J Pediatr Hematol Oncol Nurs · Clinical study
  18. Hereditary Pheochromocytoma With a Mutation in the Succinate Dehydrogenase Subunit A Gene.
    2022 · Cureus · Clinical study
  19. Feasibility and Therapeutic Potential of Combined Peptide Receptor Radionuclide Therapy With Intensive Chemotherapy for Pediatric Patients With Relapsed or Refractory Metastatic Neuroblastoma.
    2021 · Clin Nucl Med · Clinical study
  20. Addition of 131I-MIBG to PRRT (90Y-DOTATOC) for Personalized Treatment of Selected Patients with Neuroendocrine Tumors.
    2021 · J Nucl Med · Clinical study · Phase I
  21. Bilateral Adrenal Extremely Intense Metabolic Activity on 18F-FDG PET/CT in a Patient With Pheochromocytomas.
    2019 · Clin Nucl Med · Clinical study
  22. A case of pheochromocytoma with a marked decrease in catecholamine levels after rupture in which a good outcome was achieved by elective surgery.
    2018 · Endocr J · Clinical study
  23. Unusual Long Survival with a Giant Invasive Pheochromocytoma of an Incompatible Patient.
    2018 · Cureus · Clinical study
  24. Potentially fatal crisis after 177Lu-DOTATATE therapy for paraganglioma: a case report with review of literature.
    2025 · Endocr J · Case report
  25. Reply to the Letter to the Editor Concerning Metabolic and Pharmacological Interactions of 131 I-MIBG.
    2025 · Clin Nucl Med · Letter
  26. Intraoperative radiofrequency ablation for unresectable abdominal paraganglioma: a case report.
    2024 · Front Endocrinol (Lausanne) · Case report
  27. Selective use of Peptide Receptor Radionuclide Therapy following comparative imaging of Ga-68 DOTATATE PET/CT against I-131 MIBG scintigraphy in a small Asian cohort of Adult Neuroblastoma.
    2021 · Med J Malaysia · Case report
  28. Case Report: Malignant Pheochromocytoma Without Hypertension Accompanied by Increment of Serum VEGF Level and Catecholamine Cardiomyopathy.
    2021 · Front Endocrinol (Lausanne) · Case report
  29. Neuroendocrine tumour of urinary bladder: a rare case of aggressively behaving primary well-differentiated neuroendocrine tumour with review of literature.
    2019 · BMJ Case Rep · Case report
  30. Thoracic spine metastasis presenting 18 years after complete resection of a phaeochromocytoma.
    2019 · BMJ Case Rep · Case report
  31. Pheochromocytoma presenting with severe hyperglycemia and metabolic acidosis following intra-articular glucocorticoid administration: a case report.
    2019 · J Med Case Rep · Case report
  32. Pheochromocytoma as a rare cause of hypertension in a 46 X, i(X)(q10) turner syndrome: a case report and literature review.
    2018 · BMC Endocr Disord · Case report
  33. Lymphnode tuberculosis in a 4-year-old boy with relapsed ganglioneuroblastoma: a case report.
    2018 · BMC Infect Dis · Case report
  34. Composite paraganglioma-ganglioneuroma in the retroperitoneum.
    2009 · World J Surg Oncol · Case report

Precursor

Common precursor
—
Suppliers seen in the literature
—
Cited suppliers in indexed syntheses
Progenics Pharmaceuticals, Inc.
Typical final purification
—

Need this precursor?We can point you to suppliers for [131I]MIBG, or handle the enquiry for you.

Get in touch

Notes

Added at stage 21 from therapy-discovered.xlsx (bulk PubMed search by isotope/therapy-type/known-agent, not individually researched yet) -- 78 articles found. Target/mechanism, clinical application, indications, approval and precursor fields still need per-agent research and are intentionally left empty. Diagnostic pair signal at discovery: YES - I-123. Stage set/updated at stage 23 from PMID 34475242: 'the recent approval of high-specific-activity 131I-MIBG for metastatic or inoperable pheochromocytoma or paraganglioma by the U.S. Food and Drug Administration has resulted in general availability of, and renewed interest in, this treatment.'. | Stage 28: added indication(s) onc-neuroblastoma from consolidated missing-rubric review. | Stage 31 (2026-09-18): Stage left 'Approved' -- the FDA register lists both US products as 'Discontinued' but does not itself state that the approval was withdrawn; no I-131 MIBG product is currently marketed per the registers checked. Not authorised elsewhere in the registers checked: French BDPM export has only MIBG [123I] (Curium); Health Canada DPD record 'IODINE-131 META IODOBENZYLGUANIDINE' (DIN 02349515, Edmonton Radiopharmaceutical Centre) has status 'Cancelled Pre Market' (2023-06-09) -- https://health-products.canada.ca/api/drug/status/?id=83480&lang=en&type=json
Ask a question