Pharmacokinetics of indium-111 BLEDTA in man

Invest Radiol. 1984 May-Jun;19(3):221-7.

Abstract

111In-BLEDTA is a bleomycin-containing radiopharmaceutical that has proven useful as a tumor imaging agent. Whole blood distribution and pharmacokinetic parameters were studied in nine cancer patients, and the results compared with previously reported studies using 57Co-bleomycin. In eight patients studied by bolus intravenous injection, 111In-BLEDTA had a beta half-life (t1/2 beta) of 1.3 hours, a terminal-phase half-life (t1/2) of 11.7 hours, a volume of distribution (Vd gamma) of 57.5L/m2, a total body clearance rate (C1b) of 52.8 ml/min/m2, a renal clearance rate (C1r) of 23.3 ml/min/m2, and a 24-hour urinary excretion of 38.1% total administered dose. 111In-BLEDTA and 57Co-bleomycin have similar C1bs but differing Vds. Polymorphonuclear cell uptake of 111In-BLEDTA may explain its shorter t1/2 beta and t1/2, as well as its lower C1r and 24-hour urinary excretion. While the biologic characteristics of 111In-BLEDTA contribute to a greater background activity than is observed in scans with 57Co-bleomycin, its superior physical properties render it clinically more desirable as a tumor-imaging radiopharmaceutical.

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
  • Bleomycin* / metabolism
  • Chelating Agents* / metabolism
  • Cobalt Radioisotopes
  • Edetic Acid / analogs & derivatives*
  • Edetic Acid / metabolism
  • Half-Life
  • Humans
  • Indium* / metabolism
  • Kinetics
  • Male
  • Middle Aged
  • Neoplasms / diagnostic imaging*
  • Neutrophils / metabolism
  • Radioisotopes*
  • Radionuclide Imaging

Substances

  • BLEDTA
  • Chelating Agents
  • Cobalt Radioisotopes
  • Radioisotopes
  • Indium
  • Bleomycin
  • Edetic Acid