Are radiometal-labeled antibodies better than iodine-131-labeled antibodies: comparative pharmacokinetics and dosimetry of copper-67-, iodine-131-, and yttrium-90-labeled Lym-1 antibody in patients with non-Hodgkin's lymphoma

Clin Lymphoma. 2000 Sep;1(2):118-26. doi: 10.3816/clm.2000.n.010.


Radioimmunotherapy using radiolabeled monoclonal antibodies against tumor-associated antigens has been efficacious, particularly in the treatment of radiosensitive malignancies such as lymphoma. Antilymphoma monoclonal antibody Lym-1, labeled with copper-67 ((67)Cu), iodine-131 ((131)I), or yttrium-90 ((90)Y), has been effective salvage therapy for patients with non-Hodgkin's lymphoma. Although (131)I has had the dominant role in radioimmunotherapy thus far, several properties of radiometals are preferable. A total of 70 patients with B-lymphocytic non-Hodgkin's lymphoma were studied using (67)Cu-2IT-BAT-Lym-1, (131)I-Lym-1, or (111)In-2IT-BAD-Lym-1. Because (90)Y does not have good emissions for imaging, indium-111 ((111)In), its analogue, was used as a surrogate to estimate (90)Y-2IT-BAD-Lym-1 pharmacokinetics and radiation dosimetry. Subsets of four patients in each group received (67)Cu- and (131)I-labeled Lym-1 or (111)In- and (131)I-labeled Lym-1, allowing direct comparisons of the radioimmunoconjugates. Sequential blood samples and planar images were used to quantitate radioimmunoconjugate in tissues in order to determine pharmacokinetics and radiation dosimetry. (67)Cu-2IT-BAT-Lym-1 and (90)Y-2IT-BAD-Lym-1 exhibited higher cumulated activity concentrations and radiation absorbed doses per unit of administered radioactivity for tumors than did (131)I-Lym-1. The mean tumor cumulated activity (area under the time-activity curve) concentrations per unit of administered radioactivity for (67)Cu-2IT-BAT-Lym-1, (131)I-Lym-1, and (90)Y-2IT-BAD-Lym-1 were 96.89, 33.96, and 43.42 GBq-s/GBq/g, respectively. The mean tumor radiation doses from (67)Cu-2IT-BAT-Lym-1, (131)I-Lym-1, and (90)Y-2IT-BAD-Lym-1 were 2.5, 1.0, and 6.6 Gy/GBq, respectively, because (90)Y deposits more radiation per unit of administered radioactivity. Per unit of administered radioactivity, radiation doses from (67)Cu-2IT-BAT-Lym-1 and (131)I-Lym-1 to normal tissues were similar except that the liver received a higher dose from (67)Cu-2IT-BAT-Lym-1 than from (131)I-Lym-1; radiation doses to normal tissues from (90)Y-2IT-BAD-Lym-1 were generally higher. Consequently, the therapeutic indices (ratio of radiation doses to tumor and normal tissues) for (67)Cu-2IT-BAT-Lym-1, and less generally for (90)Y-2IT-BAD-Lym-1, were more favorable when compared to those for (131)I-Lym-1. Data from the matched subsets of patients showed similar therapeutic indices to those for the groups of patients. (67)Cu-2IT-BAT-Lym-1 showed more potential than (131)I-Lym-1 or (90)Y-2IT-BAD-Lym-1 for non-Hodgkin's lymphoma radioimmunotherapy.

Publication types

  • Comparative Study
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adult
  • Aged
  • Antibodies, Monoclonal / pharmacokinetics*
  • Antibodies, Monoclonal / therapeutic use
  • Antibodies, Monoclonal, Murine-Derived
  • Copper Radioisotopes / pharmacokinetics
  • Copper Radioisotopes / therapeutic use
  • Female
  • Heterocyclic Compounds / pharmacokinetics*
  • Heterocyclic Compounds / therapeutic use
  • Humans
  • Iodine Radioisotopes / pharmacokinetics*
  • Iodine Radioisotopes / therapeutic use
  • Lymphoma, Non-Hodgkin / metabolism*
  • Lymphoma, Non-Hodgkin / radiotherapy
  • Male
  • Metabolic Clearance Rate
  • Middle Aged
  • Organometallic Compounds / pharmacokinetics*
  • Organometallic Compounds / therapeutic use
  • Radioimmunotherapy
  • Radiotherapy Dosage
  • Yttrium Radioisotopes / pharmacokinetics*
  • Yttrium Radioisotopes / therapeutic use


  • 2IT-BAD-Lym-1 monoclonal antibody
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Murine-Derived
  • Copper Radioisotopes
  • Heterocyclic Compounds
  • Iodine Radioisotopes
  • Lym-1 monoclonal antibody
  • Organometallic Compounds
  • Yttrium Radioisotopes
  • copper-67-2IT-BAT-Lym-1