Tositumomab
[1] It was combined with iodine-131 to produce a radiopharmaceutical for unsealed source radiotherapy, Iodine-131 Tositumomab (branded as Bexxar), for the treatment of non-Hodgkins lymphoma.[4][7][8] The radioactive dose was adjusted for each patient in order to maximize the radiation delivered to the tumor and minimize the exposure of other organs.[10][8] Sale of Bexxar was discontinued and marketing approval was withdrawn in February 2014 due to a decline in usage (fewer than 75 patients in 2012).One possible explanation for the lack of demand, despite a claimed 70% response rate, was that oncologists could not sell it directly to patients but had to refer patients to third party specialist centers, however a "muddled clinical trials strategy", supply chain issues, reimbursement problems, and emergence of non-radioactive competitors has also been blamed.[6][5][11] The European Medicines Agency granted tositumomab and 131I-tositumomab orphan drug status, for the treatment of follicular lymphoma, to Amersham plc in 2003.