Production, isolation, and shipment of clinically relevant quantities of astatine-211: A simple and efficient...

The alpha emitter astatine-211 (²¹¹At) is a promising candidate for cancer treatment based on Targeted Alpha (α) Therapy (TAT). A small number of facilities, distributed across the United States, are capable of accelerating α-particle beams to produce ²¹¹At. However, challenges remain regarding strategic methods for shipping ²¹¹At in a form adaptable to advanced radiochemistry reactions and other uses of the radioisotope.

Our method allows shipment of ²¹¹At in various quantities in a form convenient for further radiochemistry.

For this study, a 3-octanone impregnated Amberchrom CG300M resin bed in a column cartridge was used to separate ²¹¹At from the bismuth matrix on site at the production accelerator (Texas A&M) in preparation for shipping. Aliquots of 6 M HNO₃ containing up to ≈2.22 GBq of ²¹¹At from the dissolved target were successfully loaded and retained on columns. Exempt packages (<370 MBq) were shipped to a destination radiochemistry facility, University of Texas MD Anderson Cancer Center, in the form of a convenient air-dried column. Type A packages have been shipped overnight to University of Alabama at Birmingham.

Air-dried column hold times of various lengths did not inhibit simple and efficient recovery of ²¹¹At. Solution eluted from the column was sufficiently high in specific activity to successfully radiolabel a model compound, 4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)aniline (1), with ²¹¹At. The method to prepare and ship ²¹¹At described in this manuscript has also been used to ship larger quantities of ²¹¹At a greater distance to University of Alabama at Birmingham.

The successful proof of this method paves the way for the distribution of ²¹¹At from Texas A&M University to research institutions and clinical oncology centers in Texas and elsewhere. Use of this simple method at other facilities has the potential increase the overall availability of ²¹¹At for preclinical and clinical studies.