Iodine-131 continues to be the prevalent isotope for radioimmunotherapy of cancer because it is easily incorporated into proteins and other chemical compounds. However, radiation safety concerns can influence development of clinical 131I protocols. Here, we review our experience with routine 131I labeling of monoclonal antibodies (MoAbs) for radioimmunotherapy over a 4-year interval. The antibodies were labeled with 131I by the chloramine-T reaction in a glove box fitted with charcoal filters to trap volatile radioiodine. Altogether, 14,385 mCi of 131I were used to prepare 81 batches of MoAb radiopharmaceutical that was dispensed to 82 patients in 248 syringe doses. Film badges, dosimeter rings and thyroid bioassays were used to monitor radiation dose to radiopharmacy staff. The room air and waste air from the glove box were monitored periodically for radioactive contamination. Over the 4-year interval, the 131I-MoAb radiopharmaceuticals had a mean radiochemical purity of 96% and a mean retention of immunoreactivity of 95%. Radiation dose to the radiopharmacy staff was less than 4% for body, 1% for thyroid, and 14% for hands of the United States Nuclear Regulatory Commission (NRC) limits. Levels of 131I in room air and glove box waste air were less than 10% of the NRC limits. These results reveal that large amounts of 131I-MoAb radiopharmaceuticals can be safely prepared in an appropriately equipped university radiopharmacy.
|Original language||English (US)|
|Number of pages||10|
|Journal||Antibody, Immunoconjugates, and Radiopharmaceuticals|
|State||Published - 1995|
ASJC Scopus subject areas
- Radiology Nuclear Medicine and imaging