The Basics
What is Tositumomab I 131?
Indicated for the treatment of patients with CD20-positive relapsed or refractory, low grade, follicular, or transformed non-Hodgkin’s lymphoma.
Brand names for Tositumomab I 131
Bexxar
How Tositumomab I 131 is classified
Radiopharmaceuticals, Iodine Radioisotopes
Tositumomab I 131 During Pregnancy
Tositumomab I 131 pregnancy category
Category DNote that the FDA has deprecated the use of pregnancy categories, so for some medications, this information isn’t available. We still think it’s useful to list historical info, however, given what a common proxy this has been in the past.
What we know about taking Tositumomab I 131 while pregnant
There are no studies of the BEXXAR therapeutic regimen in pregnant women or animals. Based on the transplacental passage of I-131, administration of the BEXXAR therapeutic regimen to a pregnant woman can 493 cause fetal harm including severe and possibly irreversible neonatal hypothyroidism. Limited 494 data suggest an increased risk of miscarriage up to a year following I-131 treatment. 495 Inform patients who are pregnant or become pregnant after the BEXXAR therapeutic 496 regimen about the potential hazard to a fetus. Evaluate infants born to mothers treated with the 497 BEXXAR therapeutic regimen for hypothyroidism at the time of delivery and during the 498 neonatal period.
Taking Tositumomab I 131 While Breastfeeding
What are recommendations for lactation if you're taking Tositumomab I 131?
Information in this record refers to the use of tositumomab I 131 as a therapeutic agent. No information is available on the use of tositumomab I 131 during breastfeeding. Because of the potential for serious adverse reactions in nursing infants, the manufacturer and expert opinion recommend not administering the drug in women who wish to continue breastfeeding.[1] If the drug is given, breastfeeding should be discontinued. Parents should limit close contact with their infants and small children after therapeutic tositumomab I 131 administration. Suggested contact times by one group are 30 minutes per day or less of contact at a distance of 2 meters or less for a period of 6 to 23 days.[2] Another group suggests avoiding contact with small children at a distance of 10 cm for an average of 8.1 days (range 3.5 to 12.9 days).[3] Additionally, nursing mothers may have excessive I 131 uptake by the breasts, so they should receive potassium iodide or Lugol’s solution before receiving tositumomab I 131 to block uptake by the breasts and thyroid. Nursing mothers should not work with substances containing I 131 in their workplace.[4]
Maternal / infant drug levels
Information in this record refers to the use of tositumomab I 131 as a therapeutic agent. No information is available on the use of tositumomab I 131 during breastfeeding. Because of the potential for serious adverse reactions in nursing infants, the manufacturer and expert opinion recommend not administering the drug in women who wish to continue breastfeeding.[1] If the drug is given, breastfeeding should be discontinued. Parents should limit close contact with their infants and small children after therapeutic tositumomab I 131 administration. Suggested contact times by one group are 30 minutes per day or less of contact at a distance of 2 meters or less for a period of 6 to 23 days.[2] Another group suggests avoiding contact with small children at a distance of 10 cm for an average of 8.1 days (range 3.5 to 12.9 days).[3] Additionally, nursing mothers may have excessive I 131 uptake by the breasts, so they should receive potassium iodide or Lugol’s solution before receiving tositumomab I 131 to block uptake by the breasts and thyroid. Nursing mothers should not work with substances containing I 131 in their workplace.[4]
Possible effects of Tositumomab I 131 on milk supply
Relevant published information was not found as of the revision date.
Possible alternatives to Tositumomab I 131
None listed
List of References
Lactation sources: Drugs and Lactation Database (LactMed) [Internet]. Bethesda (MD): National Library of Medicine (US); 2006-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK501922/1. Goldsmith SJ. Radioimmunotherapy of lymphoma: Bexxar and Zevalin. Semin Nucl Med. 2010;40:122-35. PMID: 20113680
2. Gates VL, Carey JE, Siegel JA et al. Nonmyeloablative iodine-131 anti-B1 radioimmunotherapy as outpatient therapy. J Nucl Med. 1998;39:1230-6. PMID: 9669400
3. Siegel JA, Kroll S, Regan D et al. A practical methodology for patient release after tositumomab and (131)I-tositumomab therapy. J Nucl Med. 2002;43:354-63. PMID: 11884495
4. Almen A, Mattsson S. Radiological protection of foetuses and breast-fed children of occupationally exposed women in nuclear medicine – Challenges for hospitals. Phys Med. 2017;43:172-7. PMID: 28882410
5. Howe DB, Beardsley M, Bakhsh S. Appendix U. Model procedure for release of patients or human research subjects administered radioactive materials. In, NUREG-1556. Consolidated guidance about materials licenses. Program-specific guidance about medical use licenses. Final report. U.S. Nuclear Regulatory Commission Office of Nuclear Material Safety and Safeguards. 2008;9, Rev. 2. http://www.nrc.gov/reading-rm/doc-collections/nuregs/staff/sr1556/v9/r2/
6. Mountford PJ, Coakley AJ. A review of the secretion of radioactivity in human breast milk: data, quantitative analysis and recommendations. Nucl Med Commun. 1989;10:15-27. PMID: 2645546
Disclaimer: This material is provided for educational purposes only and is not intended for medical advice, diagnosis, or treatment. Consult your healthcare provider with any questions.
