A simple remote system for the high-level radioiodination of monoclonal antibodies

We have developed a system for the remote control radiolabeling of monoclonal antibodies (MoAb). The system is simple, inexpensive to assemble, and completely disposable. Reagents are pneumatically manipulated into vials containing Iodogen and an anion exchange resin, wherein iodination and separation of bound from free iodine occur, respectively, and sterilized (by filter) into a final vial. Radiolabeling yields of 38.9 +/- 5.5% were consistently produced with 99.3 +/- 0.2% of the isotope bound to the antibody. These results were not significantly different from those obtained in manual iodinations. However, the radiation dose to the hands of the laboratory worker in the remote mode was reduced at least ninefold. The system is presently being introduced for 300 to 400 mCi 131I iodinations of the anti-ovarian cancer MoAb OC 125 in a Phase I radioimmunotherapy trial.