Production of Astatine-211 for U.S. Investigators

Abstract

Alpha-particle emitting radionuclides hold great promise in the therapy of cancer, but few alpha-emitters are available to investigators to evaluate. Of the alpha-emitters that have properties amenable for use in humans, 211At is of particular interest as it does not have alpha-emitting daughter radionuclides. Thus, there is a high interest in having a source of 211At for sale to investigators in the US. Production of 211At is accomplished on a cyclotron using an alpha-particle beam irradiation of bismuth metal. Unfortunately, there are few cyclotrons available that can produce an alpha particle beam for that production. The University of Washington has a cyclotron, one of three in the U.S., that is currently producing 211At. In the proposed studies, the things necessary for production and shipment of 211At to other investigators will be put into place at UW. Of major importance is the efficient production and isolation of 211At in a form that can be readily used by other investigators. In the studies, production of 211At on the UW cyclotron will be optimized by determining the best beam energy and the highest beam current to maximize 211At production. As it would be very difficult for most investigators to isolate the 211At from the irradiated target, the 211At-isolation process will be optimized and automated to more safely and efficiently obtain the 211At for shipment. Additional tasks to make the 211At available for distribution include obtaining appropriate shipping vials and containers, putting into place the requisite standard operating procedures for Radiation Safety compliance at the levels of 211At activity to be produced / shipped, and working with the Department of Energy, Isotope Development and Production for Research and Applications Program, to take orders, make shipments and be reimbursed for costs of production and shipment.